2017-06-27 10:12:17

by Ram Pai

Subject: [RFC v4 00/17] powerpc: Memory Protection Keys

Memory protection keys enable applications to protect its
address space from inadvertent access or corruption from
itself.

The overall idea:

A process allocates a key and associates it with
a address range within its address space.
The process than can dynamically set read/write
permissions on the key without involving the
kernel. Any code that violates the permissions
off the address space; as defined by its associated
key, will receive a segmentation fault.

This patch series enables the feature on PPC64 HPTE
platform.

ISA3.0 section 5.7.13 describes the detailed specifications.


Testing:
This patch series has passed all the protection key
tests available in the selftests directory.
The tests are updated to work on both x86 and powerpc.

version v4:
(1) patches no more depend on the pte bits to program
the hpte -- comment by Balbir
(2) documentation updates
(3) fixed a bug in the selftest.
(4) unlike x86, powerpc lets signal handler change key
permission bits; the change will persist across
signal handler boundaries. Earlier we allowed
the signal handler to modify a field in the siginfo
structure which would than be used by the kernel
to program the key protection register (AMR)
-- resolves a issue raised by Ben.
"Calls to sys_swapcontext with a made-up context
will end up with a crap AMR if done by code who
didn't know about that register".
(5) these changes enable protection keys on 4k-page
kernel aswell.

version v3:
(1) split the patches into smaller consumable
patches.
(2) added the ability to disable execute permission
on a key at creation.
(3) rename calc_pte_to_hpte_pkey_bits() to
pte_to_hpte_pkey_bits() -- suggested by Anshuman
(4) some code optimization and clarity in
do_page_fault()
(5) A bug fix while invalidating a hpte slot in
__hash_page_4K() -- noticed by Aneesh


version v2:
(1) documentation and selftest added
(2) fixed a bug in 4k hpte backed 64k pte where page
invalidation was not done correctly, and
initialization of second-part-of-the-pte was not
done correctly if the pte was not yet Hashed
with a hpte. Reported by Aneesh.
(3) Fixed ABI breakage caused in siginfo structure.
Reported by Anshuman.


version v1: Initial version

Ram Pai (17):
mm: introduce an additional vma bit for powerpc pkey
mm: ability to disable execute permission on a key at creation
x86: key creation with PKEY_DISABLE_EXECUTE disallowed
powerpc: Implement sys_pkey_alloc and sys_pkey_free system call
powerpc: store and restore the pkey state across context switches
powerpc: Implementation for sys_mprotect_pkey() system call
powerpc: make the hash functions protection-key aware
powerpc: Program HPTE key protection bits
powerpc: call the hash functions with the correct pkey value
powerpc: Macro the mask used for checking DSI exception
powerpc: Handle exceptions caused by pkey violation
powerpc: Deliver SEGV signal on pkey violation
selftest: Move protecton key selftest to arch neutral directory
selftest: PowerPC specific test updates to memory protection keys
Documentation: Move protecton key documentation to arch neutral
directory
Documentation: PowerPC specific updates to memory protection keys
procfs: display the protection-key number associated with a vma

Documentation/filesystems/proc.txt | 3 +-
Documentation/vm/protection-keys.txt | 134 +++
Documentation/x86/protection-keys.txt | 85 --
Makefile | 2 +-
arch/powerpc/Kconfig | 15 +
arch/powerpc/include/asm/book3s/64/hash.h | 2 +-
arch/powerpc/include/asm/book3s/64/mmu-hash.h | 19 +-
arch/powerpc/include/asm/book3s/64/mmu.h | 10 +
arch/powerpc/include/asm/book3s/64/pgtable.h | 62 ++
arch/powerpc/include/asm/mman.h | 8 +-
arch/powerpc/include/asm/mmu_context.h | 12 +
arch/powerpc/include/asm/paca.h | 1 +
arch/powerpc/include/asm/pkeys.h | 159 +++
arch/powerpc/include/asm/processor.h | 5 +
arch/powerpc/include/asm/reg.h | 7 +-
arch/powerpc/include/asm/systbl.h | 3 +
arch/powerpc/include/asm/unistd.h | 6 +-
arch/powerpc/include/uapi/asm/ptrace.h | 3 +-
arch/powerpc/include/uapi/asm/unistd.h | 3 +
arch/powerpc/kernel/asm-offsets.c | 5 +
arch/powerpc/kernel/exceptions-64s.S | 18 +-
arch/powerpc/kernel/process.c | 18 +
arch/powerpc/kernel/signal_32.c | 5 +
arch/powerpc/kernel/signal_64.c | 4 +
arch/powerpc/kernel/traps.c | 49 +
arch/powerpc/mm/Makefile | 1 +
arch/powerpc/mm/fault.c | 22 +
arch/powerpc/mm/hash64_4k.c | 4 +-
arch/powerpc/mm/hash64_64k.c | 8 +-
arch/powerpc/mm/hash_utils_64.c | 42 +-
arch/powerpc/mm/hugepage-hash64.c | 4 +-
arch/powerpc/mm/hugetlbpage-hash64.c | 5 +-
arch/powerpc/mm/mem.c | 7 +
arch/powerpc/mm/mmu_context_book3s64.c | 5 +
arch/powerpc/mm/mmu_decl.h | 5 +-
arch/powerpc/mm/pkeys.c | 256 +++++
arch/x86/kernel/fpu/xstate.c | 3 +
fs/proc/task_mmu.c | 18 +-
include/linux/mm.h | 18 +-
include/uapi/asm-generic/mman-common.h | 4 +-
tools/testing/selftests/vm/Makefile | 1 +
tools/testing/selftests/vm/pkey-helpers.h | 365 ++++++
tools/testing/selftests/vm/protection_keys.c | 1488 +++++++++++++++++++++++++
tools/testing/selftests/x86/Makefile | 2 +-
tools/testing/selftests/x86/pkey-helpers.h | 219 ----
tools/testing/selftests/x86/protection_keys.c | 1395 -----------------------
46 files changed, 2755 insertions(+), 1755 deletions(-)
create mode 100644 Documentation/vm/protection-keys.txt
delete mode 100644 Documentation/x86/protection-keys.txt
create mode 100644 arch/powerpc/include/asm/pkeys.h
create mode 100644 arch/powerpc/mm/pkeys.c
create mode 100644 tools/testing/selftests/vm/pkey-helpers.h
create mode 100644 tools/testing/selftests/vm/protection_keys.c
delete mode 100644 tools/testing/selftests/x86/pkey-helpers.h
delete mode 100644 tools/testing/selftests/x86/protection_keys.c

--
1.8.3.1

2017-06-27 10:12:39

by Ram Pai

Subject: [RFC v4 05/17] powerpc: store and restore the pkey state across context switches

Store and restore the AMR, IAMR and UMOR register state of the task
before scheduling out and after scheduling in, respectively.

Signed-off-by: Ram Pai <[email protected]>
---
arch/powerpc/include/asm/processor.h | 5 +++++
arch/powerpc/kernel/process.c | 18 ++++++++++++++++++
2 files changed, 23 insertions(+)

diff --git a/arch/powerpc/include/asm/processor.h b/arch/powerpc/include/asm/processor.h
index a2123f2..1f714df 100644
--- a/arch/powerpc/include/asm/processor.h
+++ b/arch/powerpc/include/asm/processor.h
@@ -310,6 +310,11 @@ struct thread_struct {
struct thread_vr_state ckvr_state; /* Checkpointed VR state */
unsigned long ckvrsave; /* Checkpointed VRSAVE */
#endif /* CONFIG_PPC_TRANSACTIONAL_MEM */
+#ifdef CONFIG_PPC64_MEMORY_PROTECTION_KEYS
+ unsigned long amr;
+ unsigned long iamr;
+ unsigned long uamor;
+#endif
#ifdef CONFIG_KVM_BOOK3S_32_HANDLER
void* kvm_shadow_vcpu; /* KVM internal data */
#endif /* CONFIG_KVM_BOOK3S_32_HANDLER */
diff --git a/arch/powerpc/kernel/process.c b/arch/powerpc/kernel/process.c
index baae104..37d001a 100644
--- a/arch/powerpc/kernel/process.c
+++ b/arch/powerpc/kernel/process.c
@@ -1096,6 +1096,11 @@ static inline void save_sprs(struct thread_struct *t)
t->tar = mfspr(SPRN_TAR);
}
#endif
+#ifdef CONFIG_PPC64_MEMORY_PROTECTION_KEYS
+ t->amr = mfspr(SPRN_AMR);
+ t->iamr = mfspr(SPRN_IAMR);
+ t->uamor = mfspr(SPRN_UAMOR);
+#endif
}

static inline void restore_sprs(struct thread_struct *old_thread,
@@ -1131,6 +1136,14 @@ static inline void restore_sprs(struct thread_struct *old_thread,
mtspr(SPRN_TAR, new_thread->tar);
}
#endif
+#ifdef CONFIG_PPC64_MEMORY_PROTECTION_KEYS
+ if (old_thread->amr != new_thread->amr)
+ mtspr(SPRN_AMR, new_thread->amr);
+ if (old_thread->iamr != new_thread->iamr)
+ mtspr(SPRN_IAMR, new_thread->iamr);
+ if (old_thread->uamor != new_thread->uamor)
+ mtspr(SPRN_UAMOR, new_thread->uamor);
+#endif
}

struct task_struct *__switch_to(struct task_struct *prev,
@@ -1686,6 +1699,11 @@ void start_thread(struct pt_regs *regs, unsigned long start, unsigned long sp)
current->thread.tm_texasr = 0;
current->thread.tm_tfiar = 0;
#endif /* CONFIG_PPC_TRANSACTIONAL_MEM */
+#ifdef CONFIG_PPC64_MEMORY_PROTECTION_KEYS
+ current->thread.amr = 0x0ul;
+ current->thread.iamr = 0x0ul;
+ current->thread.uamor = 0x0ul;
+#endif /* CONFIG_PPC64_MEMORY_PROTECTION_KEYS */
}
EXPORT_SYMBOL(start_thread);

--
1.8.3.1

2017-06-27 10:12:44

by Ram Pai

Subject: [RFC v4 03/17] x86: key creation with PKEY_DISABLE_EXECUTE disallowed

x86 does not support disabling execute permissions on a pkey.

Signed-off-by: Ram Pai <[email protected]>
---
arch/x86/kernel/fpu/xstate.c | 3 +++
1 file changed, 3 insertions(+)

diff --git a/arch/x86/kernel/fpu/xstate.c b/arch/x86/kernel/fpu/xstate.c
index c24ac1e..d582631 100644
--- a/arch/x86/kernel/fpu/xstate.c
+++ b/arch/x86/kernel/fpu/xstate.c
@@ -900,6 +900,9 @@ int arch_set_user_pkey_access(struct task_struct *tsk, int pkey,
if (!boot_cpu_has(X86_FEATURE_OSPKE))
return -EINVAL;

+ if (init_val & PKEY_DISABLE_EXECUTE)
+ return -EINVAL;
+
/* Set the bits we need in PKRU: */
if (init_val & PKEY_DISABLE_ACCESS)
new_pkru_bits |= PKRU_AD_BIT;
--
1.8.3.1

2017-06-27 10:12:50

by Ram Pai

Subject: [RFC v4 11/17] powerpc: Handle exceptions caused by pkey violation

Handle Data and Instruction exceptions caused by memory
protection-key.

Signed-off-by: Ram Pai <[email protected]>
---
arch/powerpc/include/asm/mmu_context.h | 12 ++++++
arch/powerpc/include/asm/reg.h | 2 +-
arch/powerpc/mm/fault.c | 20 +++++++++
arch/powerpc/mm/pkeys.c | 79 ++++++++++++++++++++++++++++++++++
4 files changed, 112 insertions(+), 1 deletion(-)

diff --git a/arch/powerpc/include/asm/mmu_context.h b/arch/powerpc/include/asm/mmu_context.h
index da7e943..71fffe0 100644
--- a/arch/powerpc/include/asm/mmu_context.h
+++ b/arch/powerpc/include/asm/mmu_context.h
@@ -175,11 +175,23 @@ static inline void arch_bprm_mm_init(struct mm_struct *mm,
{
}

+#ifdef CONFIG_PPC64_MEMORY_PROTECTION_KEYS
+bool arch_pte_access_permitted(pte_t pte, bool write);
+bool arch_vma_access_permitted(struct vm_area_struct *vma,
+ bool write, bool execute, bool foreign);
+#else /* CONFIG_PPC64_MEMORY_PROTECTION_KEYS */
+static inline bool arch_pte_access_permitted(pte_t pte, bool write)
+{
+ /* by default, allow everything */
+ return true;
+}
static inline bool arch_vma_access_permitted(struct vm_area_struct *vma,
bool write, bool execute, bool foreign)
{
/* by default, allow everything */
return true;
}
+#endif /* CONFIG_PPC64_MEMORY_PROTECTION_KEYS */
+
#endif /* __KERNEL__ */
#endif /* __ASM_POWERPC_MMU_CONTEXT_H */
diff --git a/arch/powerpc/include/asm/reg.h b/arch/powerpc/include/asm/reg.h
index ba110dd..6e2a860 100644
--- a/arch/powerpc/include/asm/reg.h
+++ b/arch/powerpc/include/asm/reg.h
@@ -286,7 +286,7 @@
#define DSISR_SET_RC 0x00040000 /* Failed setting of R/C bits */
#define DSISR_PGDIRFAULT 0x00020000 /* Fault on page directory */
#define DSISR_PAGE_FAULT_MASK (DSISR_BIT32 | DSISR_PAGEATTR_CONFLT | \
- DSISR_BADACCESS | DSISR_BIT43)
+ DSISR_BADACCESS | DSISR_KEYFAULT | DSISR_BIT43)
#define SPRN_TBRL 0x10C /* Time Base Read Lower Register (user, R/O) */
#define SPRN_TBRU 0x10D /* Time Base Read Upper Register (user, R/O) */
#define SPRN_CIR 0x11B /* Chip Information Register (hyper, R/0) */
diff --git a/arch/powerpc/mm/fault.c b/arch/powerpc/mm/fault.c
index 3a7d580..3d71984 100644
--- a/arch/powerpc/mm/fault.c
+++ b/arch/powerpc/mm/fault.c
@@ -261,6 +261,13 @@ int do_page_fault(struct pt_regs *regs, unsigned long address,
}
#endif

+#ifdef CONFIG_PPC64_MEMORY_PROTECTION_KEYS
+ if (error_code & DSISR_KEYFAULT) {
+ code = SEGV_PKUERR;
+ goto bad_area_nosemaphore;
+ }
+#endif /* CONFIG_PPC64_MEMORY_PROTECTION_KEYS */
+
/* We restore the interrupt state now */
if (!arch_irq_disabled_regs(regs))
local_irq_enable();
@@ -441,6 +448,19 @@ int do_page_fault(struct pt_regs *regs, unsigned long address,
WARN_ON_ONCE(error_code & DSISR_PROTFAULT);
#endif /* CONFIG_PPC_STD_MMU */

+#ifdef CONFIG_PPC64_MEMORY_PROTECTION_KEYS
+ if (!arch_vma_access_permitted(vma, flags & FAULT_FLAG_WRITE,
+ is_exec, 0)) {
+ code = SEGV_PKUERR;
+ goto bad_area;
+ }
+#endif /* CONFIG_PPC64_MEMORY_PROTECTION_KEYS */
+
+ /* handle_mm_fault() needs to know if its a instruction access
+ * fault.
+ */
+ if (is_exec)
+ flags |= FAULT_FLAG_INSTRUCTION;
/*
* If for any reason at all we couldn't handle the fault,
* make sure we exit gracefully rather than endlessly redo
diff --git a/arch/powerpc/mm/pkeys.c b/arch/powerpc/mm/pkeys.c
index 11a32b3..514f503 100644
--- a/arch/powerpc/mm/pkeys.c
+++ b/arch/powerpc/mm/pkeys.c
@@ -27,6 +27,37 @@ static inline bool pkey_allows_readwrite(int pkey)
return !(read_amr() & ((AMR_AD_BIT|AMR_WD_BIT) << pkey_shift));
}

+static inline bool pkey_allows_read(int pkey)
+{
+ int pkey_shift = (arch_max_pkey()-pkey-1) * AMR_BITS_PER_PKEY;
+
+ if (!(read_uamor() & (0x3ul << pkey_shift)))
+ return true;
+
+ return !(read_amr() & (AMR_AD_BIT << pkey_shift));
+}
+
+static inline bool pkey_allows_write(int pkey)
+{
+ int pkey_shift = (arch_max_pkey()-pkey-1) * AMR_BITS_PER_PKEY;
+
+ if (!(read_uamor() & (0x3ul << pkey_shift)))
+ return true;
+
+ return !(read_amr() & (AMR_WD_BIT << pkey_shift));
+}
+
+static inline bool pkey_allows_execute(int pkey)
+{
+ int pkey_shift = (arch_max_pkey()-pkey-1) * AMR_BITS_PER_PKEY;
+
+ if (!(read_uamor() & (0x3ul << pkey_shift)))
+ return true;
+
+ return !(read_iamr() & (IAMR_EX_BIT << pkey_shift));
+}
+
+
/*
* set the access right in AMR IAMR and UAMOR register
* for @pkey to that specified in @init_val.
@@ -175,3 +206,51 @@ int __arch_override_mprotect_pkey(struct vm_area_struct *vma, int prot,
*/
return vma_pkey(vma);
}
+
+/*
+ * We only want to enforce protection keys on the current process
+ * because we effectively have no access to AMR/IAMR for other
+ * processes or any way to tell *which * AMR/IAMR in a threaded
+ * process we could use.
+ *
+ * So do not enforce things if the VMA is not from the current
+ * mm, or if we are in a kernel thread.
+ */
+static inline bool vma_is_foreign(struct vm_area_struct *vma)
+{
+ if (!current->mm)
+ return true;
+ /*
+ * if the VMA is from another process, then AMR/IAMR has no
+ * relevance and should not be enforced.
+ */
+ if (current->mm != vma->vm_mm)
+ return true;
+
+ return false;
+}
+
+bool arch_vma_access_permitted(struct vm_area_struct *vma,
+ bool write, bool execute, bool foreign)
+{
+ int pkey;
+ /* allow access if the VMA is not one from this process */
+ if (foreign || vma_is_foreign(vma))
+ return true;
+
+ pkey = vma_pkey(vma);
+
+ if (!pkey)
+ return true;
+
+ if (execute)
+ return pkey_allows_execute(pkey);
+
+ if (!pkey_allows_read(pkey))
+ return false;
+
+ if (write)
+ return pkey_allows_write(pkey);
+
+ return true;
+}
--
1.8.3.1

2017-06-27 10:13:10

by Ram Pai

Subject: [RFC v4 13/17] selftest: Move protecton key selftest to arch neutral directory

Signed-off-by: Ram Pai <[email protected]>
---
tools/testing/selftests/vm/Makefile | 1 +
tools/testing/selftests/vm/pkey-helpers.h | 219 ++++
tools/testing/selftests/vm/protection_keys.c | 1395 +++++++++++++++++++++++++
tools/testing/selftests/x86/Makefile | 2 +-
tools/testing/selftests/x86/pkey-helpers.h | 219 ----
tools/testing/selftests/x86/protection_keys.c | 1395 -------------------------
6 files changed, 1616 insertions(+), 1615 deletions(-)
create mode 100644 tools/testing/selftests/vm/pkey-helpers.h
create mode 100644 tools/testing/selftests/vm/protection_keys.c
delete mode 100644 tools/testing/selftests/x86/pkey-helpers.h
delete mode 100644 tools/testing/selftests/x86/protection_keys.c

diff --git a/tools/testing/selftests/vm/Makefile b/tools/testing/selftests/vm/Makefile
index cbb29e4..1d32f78 100644
--- a/tools/testing/selftests/vm/Makefile
+++ b/tools/testing/selftests/vm/Makefile
@@ -17,6 +17,7 @@ TEST_GEN_FILES += transhuge-stress
TEST_GEN_FILES += userfaultfd
TEST_GEN_FILES += mlock-random-test
TEST_GEN_FILES += virtual_address_range
+TEST_GEN_FILES += protection_keys

TEST_PROGS := run_vmtests

diff --git a/tools/testing/selftests/vm/pkey-helpers.h b/tools/testing/selftests/vm/pkey-helpers.h
new file mode 100644
index 0000000..b202939
--- /dev/null
+++ b/tools/testing/selftests/vm/pkey-helpers.h
@@ -0,0 +1,219 @@
+#ifndef _PKEYS_HELPER_H
+#define _PKEYS_HELPER_H
+#define _GNU_SOURCE
+#include <string.h>
+#include <stdarg.h>
+#include <stdio.h>
+#include <stdint.h>
+#include <stdbool.h>
+#include <signal.h>
+#include <assert.h>
+#include <stdlib.h>
+#include <ucontext.h>
+#include <sys/mman.h>
+
+#define NR_PKEYS 16
+#define PKRU_BITS_PER_PKEY 2
+
+#ifndef DEBUG_LEVEL
+#define DEBUG_LEVEL 0
+#endif
+#define DPRINT_IN_SIGNAL_BUF_SIZE 4096
+extern int dprint_in_signal;
+extern char dprint_in_signal_buffer[DPRINT_IN_SIGNAL_BUF_SIZE];
+static inline void sigsafe_printf(const char *format, ...)
+{
+ va_list ap;
+
+ va_start(ap, format);
+ if (!dprint_in_signal) {
+ vprintf(format, ap);
+ } else {
+ int len = vsnprintf(dprint_in_signal_buffer,
+ DPRINT_IN_SIGNAL_BUF_SIZE,
+ format, ap);
+ /*
+ * len is amount that would have been printed,
+ * but actual write is truncated at BUF_SIZE.
+ */
+ if (len > DPRINT_IN_SIGNAL_BUF_SIZE)
+ len = DPRINT_IN_SIGNAL_BUF_SIZE;
+ write(1, dprint_in_signal_buffer, len);
+ }
+ va_end(ap);
+}
+#define dprintf_level(level, args...) do { \
+ if (level <= DEBUG_LEVEL) \
+ sigsafe_printf(args); \
+ fflush(NULL); \
+} while (0)
+#define dprintf0(args...) dprintf_level(0, args)
+#define dprintf1(args...) dprintf_level(1, args)
+#define dprintf2(args...) dprintf_level(2, args)
+#define dprintf3(args...) dprintf_level(3, args)
+#define dprintf4(args...) dprintf_level(4, args)
+
+extern unsigned int shadow_pkru;
+static inline unsigned int __rdpkru(void)
+{
+ unsigned int eax, edx;
+ unsigned int ecx = 0;
+ unsigned int pkru;
+
+ asm volatile(".byte 0x0f,0x01,0xee\n\t"
+ : "=a" (eax), "=d" (edx)
+ : "c" (ecx));
+ pkru = eax;
+ return pkru;
+}
+
+static inline unsigned int _rdpkru(int line)
+{
+ unsigned int pkru = __rdpkru();
+
+ dprintf4("rdpkru(line=%d) pkru: %x shadow: %x\n",
+ line, pkru, shadow_pkru);
+ assert(pkru == shadow_pkru);
+
+ return pkru;
+}
+
+#define rdpkru() _rdpkru(__LINE__)
+
+static inline void __wrpkru(unsigned int pkru)
+{
+ unsigned int eax = pkru;
+ unsigned int ecx = 0;
+ unsigned int edx = 0;
+
+ dprintf4("%s() changing %08x to %08x\n", __func__, __rdpkru(), pkru);
+ asm volatile(".byte 0x0f,0x01,0xef\n\t"
+ : : "a" (eax), "c" (ecx), "d" (edx));
+ assert(pkru == __rdpkru());
+}
+
+static inline void wrpkru(unsigned int pkru)
+{
+ dprintf4("%s() changing %08x to %08x\n", __func__, __rdpkru(), pkru);
+ /* will do the shadow check for us: */
+ rdpkru();
+ __wrpkru(pkru);
+ shadow_pkru = pkru;
+ dprintf4("%s(%08x) pkru: %08x\n", __func__, pkru, __rdpkru());
+}
+
+/*
+ * These are technically racy. since something could
+ * change PKRU between the read and the write.
+ */
+static inline void __pkey_access_allow(int pkey, int do_allow)
+{
+ unsigned int pkru = rdpkru();
+ int bit = pkey * 2;
+
+ if (do_allow)
+ pkru &= (1<<bit);
+ else
+ pkru |= (1<<bit);
+
+ dprintf4("pkru now: %08x\n", rdpkru());
+ wrpkru(pkru);
+}
+
+static inline void __pkey_write_allow(int pkey, int do_allow_write)
+{
+ long pkru = rdpkru();
+ int bit = pkey * 2 + 1;
+
+ if (do_allow_write)
+ pkru &= (1<<bit);
+ else
+ pkru |= (1<<bit);
+
+ wrpkru(pkru);
+ dprintf4("pkru now: %08x\n", rdpkru());
+}
+
+#define PROT_PKEY0 0x10 /* protection key value (bit 0) */
+#define PROT_PKEY1 0x20 /* protection key value (bit 1) */
+#define PROT_PKEY2 0x40 /* protection key value (bit 2) */
+#define PROT_PKEY3 0x80 /* protection key value (bit 3) */
+
+#define PAGE_SIZE 4096
+#define MB (1<<20)
+
+static inline void __cpuid(unsigned int *eax, unsigned int *ebx,
+ unsigned int *ecx, unsigned int *edx)
+{
+ /* ecx is often an input as well as an output. */
+ asm volatile(
+ "cpuid;"
+ : "=a" (*eax),
+ "=b" (*ebx),
+ "=c" (*ecx),
+ "=d" (*edx)
+ : "0" (*eax), "2" (*ecx));
+}
+
+/* Intel-defined CPU features, CPUID level 0x00000007:0 (ecx) */
+#define X86_FEATURE_PKU (1<<3) /* Protection Keys for Userspace */
+#define X86_FEATURE_OSPKE (1<<4) /* OS Protection Keys Enable */
+
+static inline int cpu_has_pku(void)
+{
+ unsigned int eax;
+ unsigned int ebx;
+ unsigned int ecx;
+ unsigned int edx;
+
+ eax = 0x7;
+ ecx = 0x0;
+ __cpuid(&eax, &ebx, &ecx, &edx);
+
+ if (!(ecx & X86_FEATURE_PKU)) {
+ dprintf2("cpu does not have PKU\n");
+ return 0;
+ }
+ if (!(ecx & X86_FEATURE_OSPKE)) {
+ dprintf2("cpu does not have OSPKE\n");
+ return 0;
+ }
+ return 1;
+}
+
+#define XSTATE_PKRU_BIT (9)
+#define XSTATE_PKRU 0x200
+
+int pkru_xstate_offset(void)
+{
+ unsigned int eax;
+ unsigned int ebx;
+ unsigned int ecx;
+ unsigned int edx;
+ int xstate_offset;
+ int xstate_size;
+ unsigned long XSTATE_CPUID = 0xd;
+ int leaf;
+
+ /* assume that XSTATE_PKRU is set in XCR0 */
+ leaf = XSTATE_PKRU_BIT;
+ {
+ eax = XSTATE_CPUID;
+ ecx = leaf;
+ __cpuid(&eax, &ebx, &ecx, &edx);
+
+ if (leaf == XSTATE_PKRU_BIT) {
+ xstate_offset = ebx;
+ xstate_size = eax;
+ }
+ }
+
+ if (xstate_size == 0) {
+ printf("could not find size/offset of PKRU in xsave state\n");
+ return 0;
+ }
+
+ return xstate_offset;
+}
+
+#endif /* _PKEYS_HELPER_H */
diff --git a/tools/testing/selftests/vm/protection_keys.c b/tools/testing/selftests/vm/protection_keys.c
new file mode 100644
index 0000000..3237bc0
--- /dev/null
+++ b/tools/testing/selftests/vm/protection_keys.c
@@ -0,0 +1,1395 @@
+/*
+ * Tests x86 Memory Protection Keys (see Documentation/x86/protection-keys.txt)
+ *
+ * There are examples in here of:
+ * * how to set protection keys on memory
+ * * how to set/clear bits in PKRU (the rights register)
+ * * how to handle SEGV_PKRU signals and extract pkey-relevant
+ * information from the siginfo
+ *
+ * Things to add:
+ * make sure KSM and KSM COW breaking works
+ * prefault pages in at malloc, or not
+ * protect MPX bounds tables with protection keys?
+ * make sure VMA splitting/merging is working correctly
+ * OOMs can destroy mm->mmap (see exit_mmap()), so make sure it is immune to pkeys
+ * look for pkey "leaks" where it is still set on a VMA but "freed" back to the kernel
+ * do a plain mprotect() to a mprotect_pkey() area and make sure the pkey sticks
+ *
+ * Compile like this:
+ * gcc -o protection_keys -O2 -g -std=gnu99 -pthread -Wall protection_keys.c -lrt -ldl -lm
+ * gcc -m32 -o protection_keys_32 -O2 -g -std=gnu99 -pthread -Wall protection_keys.c -lrt -ldl -lm
+ */
+#define _GNU_SOURCE
+#include <errno.h>
+#include <linux/futex.h>
+#include <sys/time.h>
+#include <sys/syscall.h>
+#include <string.h>
+#include <stdio.h>
+#include <stdint.h>
+#include <stdbool.h>
+#include <signal.h>
+#include <assert.h>
+#include <stdlib.h>
+#include <ucontext.h>
+#include <sys/mman.h>
+#include <sys/types.h>
+#include <sys/wait.h>
+#include <sys/stat.h>
+#include <fcntl.h>
+#include <unistd.h>
+#include <sys/ptrace.h>
+#include <setjmp.h>
+
+#include "pkey-helpers.h"
+
+int iteration_nr = 1;
+int test_nr;
+
+unsigned int shadow_pkru;
+
+#define HPAGE_SIZE (1UL<<21)
+#define ARRAY_SIZE(x) (sizeof(x) / sizeof(*(x)))
+#define ALIGN_UP(x, align_to) (((x) + ((align_to)-1)) & ~((align_to)-1))
+#define ALIGN_DOWN(x, align_to) ((x) & ~((align_to)-1))
+#define ALIGN_PTR_UP(p, ptr_align_to) ((typeof(p))ALIGN_UP((unsigned long)(p), ptr_align_to))
+#define ALIGN_PTR_DOWN(p, ptr_align_to) ((typeof(p))ALIGN_DOWN((unsigned long)(p), ptr_align_to))
+#define __stringify_1(x...) #x
+#define __stringify(x...) __stringify_1(x)
+
+#define PTR_ERR_ENOTSUP ((void *)-ENOTSUP)
+
+int dprint_in_signal;
+char dprint_in_signal_buffer[DPRINT_IN_SIGNAL_BUF_SIZE];
+
+extern void abort_hooks(void);
+#define pkey_assert(condition) do { \
+ if (!(condition)) { \
+ dprintf0("assert() at %s::%d test_nr: %d iteration: %d\n", \
+ __FILE__, __LINE__, \
+ test_nr, iteration_nr); \
+ dprintf0("errno at assert: %d", errno); \
+ abort_hooks(); \
+ assert(condition); \
+ } \
+} while (0)
+#define raw_assert(cond) assert(cond)
+
+void cat_into_file(char *str, char *file)
+{
+ int fd = open(file, O_RDWR);
+ int ret;
+
+ dprintf2("%s(): writing '%s' to '%s'\n", __func__, str, file);
+ /*
+ * these need to be raw because they are called under
+ * pkey_assert()
+ */
+ raw_assert(fd >= 0);
+ ret = write(fd, str, strlen(str));
+ if (ret != strlen(str)) {
+ perror("write to file failed");
+ fprintf(stderr, "filename: '%s' str: '%s'\n", file, str);
+ raw_assert(0);
+ }
+ close(fd);
+}
+
+#if CONTROL_TRACING > 0
+static int warned_tracing;
+int tracing_root_ok(void)
+{
+ if (geteuid() != 0) {
+ if (!warned_tracing)
+ fprintf(stderr, "WARNING: not run as root, "
+ "can not do tracing control\n");
+ warned_tracing = 1;
+ return 0;
+ }
+ return 1;
+}
+#endif
+
+void tracing_on(void)
+{
+#if CONTROL_TRACING > 0
+#define TRACEDIR "/sys/kernel/debug/tracing"
+ char pidstr[32];
+
+ if (!tracing_root_ok())
+ return;
+
+ sprintf(pidstr, "%d", getpid());
+ cat_into_file("0", TRACEDIR "/tracing_on");
+ cat_into_file("\n", TRACEDIR "/trace");
+ if (1) {
+ cat_into_file("function_graph", TRACEDIR "/current_tracer");
+ cat_into_file("1", TRACEDIR "/options/funcgraph-proc");
+ } else {
+ cat_into_file("nop", TRACEDIR "/current_tracer");
+ }
+ cat_into_file(pidstr, TRACEDIR "/set_ftrace_pid");
+ cat_into_file("1", TRACEDIR "/tracing_on");
+ dprintf1("enabled tracing\n");
+#endif
+}
+
+void tracing_off(void)
+{
+#if CONTROL_TRACING > 0
+ if (!tracing_root_ok())
+ return;
+ cat_into_file("0", "/sys/kernel/debug/tracing/tracing_on");
+#endif
+}
+
+void abort_hooks(void)
+{
+ fprintf(stderr, "running %s()...\n", __func__);
+ tracing_off();
+#ifdef SLEEP_ON_ABORT
+ sleep(SLEEP_ON_ABORT);
+#endif
+}
+
+static inline void __page_o_noops(void)
+{
+ /* 8-bytes of instruction * 512 bytes = 1 page */
+ asm(".rept 512 ; nopl 0x7eeeeeee(%eax) ; .endr");
+}
+
+/*
+ * This attempts to have roughly a page of instructions followed by a few
+ * instructions that do a write, and another page of instructions. That
+ * way, we are pretty sure that the write is in the second page of
+ * instructions and has at least a page of padding behind it.
+ *
+ * *That* lets us be sure to madvise() away the write instruction, which
+ * will then fault, which makes sure that the fault code handles
+ * execute-only memory properly.
+ */
+__attribute__((__aligned__(PAGE_SIZE)))
+void lots_o_noops_around_write(int *write_to_me)
+{
+ dprintf3("running %s()\n", __func__);
+ __page_o_noops();
+ /* Assume this happens in the second page of instructions: */
+ *write_to_me = __LINE__;
+ /* pad out by another page: */
+ __page_o_noops();
+ dprintf3("%s() done\n", __func__);
+}
+
+/* Define some kernel-like types */
+#define u8 uint8_t
+#define u16 uint16_t
+#define u32 uint32_t
+#define u64 uint64_t
+
+#ifdef __i386__
+#define SYS_mprotect_key 380
+#define SYS_pkey_alloc 381
+#define SYS_pkey_free 382
+#define REG_IP_IDX REG_EIP
+#define si_pkey_offset 0x14
+#else
+#define SYS_mprotect_key 329
+#define SYS_pkey_alloc 330
+#define SYS_pkey_free 331
+#define REG_IP_IDX REG_RIP
+#define si_pkey_offset 0x20
+#endif
+
+void dump_mem(void *dumpme, int len_bytes)
+{
+ char *c = (void *)dumpme;
+ int i;
+
+ for (i = 0; i < len_bytes; i += sizeof(u64)) {
+ u64 *ptr = (u64 *)(c + i);
+ dprintf1("dump[%03d][@%p]: %016jx\n", i, ptr, *ptr);
+ }
+}
+
+#define __SI_FAULT (3 << 16)
+#define SEGV_BNDERR (__SI_FAULT|3) /* failed address bound checks */
+#define SEGV_PKUERR (__SI_FAULT|4)
+
+static char *si_code_str(int si_code)
+{
+ if (si_code & SEGV_MAPERR)
+ return "SEGV_MAPERR";
+ if (si_code & SEGV_ACCERR)
+ return "SEGV_ACCERR";
+ if (si_code & SEGV_BNDERR)
+ return "SEGV_BNDERR";
+ if (si_code & SEGV_PKUERR)
+ return "SEGV_PKUERR";
+ return "UNKNOWN";
+}
+
+int pkru_faults;
+int last_si_pkey = -1;
+void signal_handler(int signum, siginfo_t *si, void *vucontext)
+{
+ ucontext_t *uctxt = vucontext;
+ int trapno;
+ unsigned long ip;
+ char *fpregs;
+ u32 *pkru_ptr;
+ u64 si_pkey;
+ u32 *si_pkey_ptr;
+ int pkru_offset;
+ fpregset_t fpregset;
+
+ dprint_in_signal = 1;
+ dprintf1(">>>>===============SIGSEGV============================\n");
+ dprintf1("%s()::%d, pkru: 0x%x shadow: %x\n", __func__, __LINE__,
+ __rdpkru(), shadow_pkru);
+
+ trapno = uctxt->uc_mcontext.gregs[REG_TRAPNO];
+ ip = uctxt->uc_mcontext.gregs[REG_IP_IDX];
+ fpregset = uctxt->uc_mcontext.fpregs;
+ fpregs = (void *)fpregset;
+
+ dprintf2("%s() trapno: %d ip: 0x%lx info->si_code: %s/%d\n", __func__,
+ trapno, ip, si_code_str(si->si_code), si->si_code);
+#ifdef __i386__
+ /*
+ * 32-bit has some extra padding so that userspace can tell whether
+ * the XSTATE header is present in addition to the "legacy" FPU
+ * state. We just assume that it is here.
+ */
+ fpregs += 0x70;
+#endif
+ pkru_offset = pkru_xstate_offset();
+ pkru_ptr = (void *)(&fpregs[pkru_offset]);
+
+ dprintf1("siginfo: %p\n", si);
+ dprintf1(" fpregs: %p\n", fpregs);
+ /*
+ * If we got a PKRU fault, we *HAVE* to have at least one bit set in
+ * here.
+ */
+ dprintf1("pkru_xstate_offset: %d\n", pkru_xstate_offset());
+ if (DEBUG_LEVEL > 4)
+ dump_mem(pkru_ptr - 128, 256);
+ pkey_assert(*pkru_ptr);
+
+ si_pkey_ptr = (u32 *)(((u8 *)si) + si_pkey_offset);
+ dprintf1("si_pkey_ptr: %p\n", si_pkey_ptr);
+ dump_mem(si_pkey_ptr - 8, 24);
+ si_pkey = *si_pkey_ptr;
+ pkey_assert(si_pkey < NR_PKEYS);
+ last_si_pkey = si_pkey;
+
+ if ((si->si_code == SEGV_MAPERR) ||
+ (si->si_code == SEGV_ACCERR) ||
+ (si->si_code == SEGV_BNDERR)) {
+ printf("non-PK si_code, exiting...\n");
+ exit(4);
+ }
+
+ dprintf1("signal pkru from xsave: %08x\n", *pkru_ptr);
+ /* need __rdpkru() version so we do not do shadow_pkru checking */
+ dprintf1("signal pkru from pkru: %08x\n", __rdpkru());
+ dprintf1("si_pkey from siginfo: %jx\n", si_pkey);
+ *(u64 *)pkru_ptr = 0x00000000;
+ dprintf1("WARNING: set PRKU=0 to allow faulting instruction to continue\n");
+ pkru_faults++;
+ dprintf1("<<<<==================================================\n");
+ return;
+ if (trapno == 14) {
+ fprintf(stderr,
+ "ERROR: In signal handler, page fault, trapno = %d, ip = %016lx\n",
+ trapno, ip);
+ fprintf(stderr, "si_addr %p\n", si->si_addr);
+ fprintf(stderr, "REG_ERR: %lx\n",
+ (unsigned long)uctxt->uc_mcontext.gregs[REG_ERR]);
+ exit(1);
+ } else {
+ fprintf(stderr, "unexpected trap %d! at 0x%lx\n", trapno, ip);
+ fprintf(stderr, "si_addr %p\n", si->si_addr);
+ fprintf(stderr, "REG_ERR: %lx\n",
+ (unsigned long)uctxt->uc_mcontext.gregs[REG_ERR]);
+ exit(2);
+ }
+ dprint_in_signal = 0;
+}
+
+int wait_all_children(void)
+{
+ int status;
+ return waitpid(-1, &status, 0);
+}
+
+void sig_chld(int x)
+{
+ dprint_in_signal = 1;
+ dprintf2("[%d] SIGCHLD: %d\n", getpid(), x);
+ dprint_in_signal = 0;
+}
+
+void setup_sigsegv_handler(void)
+{
+ int r, rs;
+ struct sigaction newact;
+ struct sigaction oldact;
+
+ /* #PF is mapped to sigsegv */
+ int signum = SIGSEGV;
+
+ newact.sa_handler = 0;
+ newact.sa_sigaction = signal_handler;
+
+ /*sigset_t - signals to block while in the handler */
+ /* get the old signal mask. */
+ rs = sigprocmask(SIG_SETMASK, 0, &newact.sa_mask);
+ pkey_assert(rs == 0);
+
+ /* call sa_sigaction, not sa_handler*/
+ newact.sa_flags = SA_SIGINFO;
+
+ newact.sa_restorer = 0; /* void(*)(), obsolete */
+ r = sigaction(signum, &newact, &oldact);
+ r = sigaction(SIGALRM, &newact, &oldact);
+ pkey_assert(r == 0);
+}
+
+void setup_handlers(void)
+{
+ signal(SIGCHLD, &sig_chld);
+ setup_sigsegv_handler();
+}
+
+pid_t fork_lazy_child(void)
+{
+ pid_t forkret;
+
+ forkret = fork();
+ pkey_assert(forkret >= 0);
+ dprintf3("[%d] fork() ret: %d\n", getpid(), forkret);
+
+ if (!forkret) {
+ /* in the child */
+ while (1) {
+ dprintf1("child sleeping...\n");
+ sleep(30);
+ }
+ }
+ return forkret;
+}
+
+void davecmp(void *_a, void *_b, int len)
+{
+ int i;
+ unsigned long *a = _a;
+ unsigned long *b = _b;
+
+ for (i = 0; i < len / sizeof(*a); i++) {
+ if (a[i] == b[i])
+ continue;
+
+ dprintf3("[%3d]: a: %016lx b: %016lx\n", i, a[i], b[i]);
+ }
+}
+
+void dumpit(char *f)
+{
+ int fd = open(f, O_RDONLY);
+ char buf[100];
+ int nr_read;
+
+ dprintf2("maps fd: %d\n", fd);
+ do {
+ nr_read = read(fd, &buf[0], sizeof(buf));
+ write(1, buf, nr_read);
+ } while (nr_read > 0);
+ close(fd);
+}
+
+#define PKEY_DISABLE_ACCESS 0x1
+#define PKEY_DISABLE_WRITE 0x2
+
+u32 pkey_get(int pkey, unsigned long flags)
+{
+ u32 mask = (PKEY_DISABLE_ACCESS|PKEY_DISABLE_WRITE);
+ u32 pkru = __rdpkru();
+ u32 shifted_pkru;
+ u32 masked_pkru;
+
+ dprintf1("%s(pkey=%d, flags=%lx) = %x / %d\n",
+ __func__, pkey, flags, 0, 0);
+ dprintf2("%s() raw pkru: %x\n", __func__, pkru);
+
+ shifted_pkru = (pkru >> (pkey * PKRU_BITS_PER_PKEY));
+ dprintf2("%s() shifted_pkru: %x\n", __func__, shifted_pkru);
+ masked_pkru = shifted_pkru & mask;
+ dprintf2("%s() masked pkru: %x\n", __func__, masked_pkru);
+ /*
+ * shift down the relevant bits to the lowest two, then
+ * mask off all the other high bits.
+ */
+ return masked_pkru;
+}
+
+int pkey_set(int pkey, unsigned long rights, unsigned long flags)
+{
+ u32 mask = (PKEY_DISABLE_ACCESS|PKEY_DISABLE_WRITE);
+ u32 old_pkru = __rdpkru();
+ u32 new_pkru;
+
+ /* make sure that 'rights' only contains the bits we expect: */
+ assert(!(rights & ~mask));
+
+ /* copy old pkru */
+ new_pkru = old_pkru;
+ /* mask out bits from pkey in old value: */
+ new_pkru &= ~(mask << (pkey * PKRU_BITS_PER_PKEY));
+ /* OR in new bits for pkey: */
+ new_pkru |= (rights << (pkey * PKRU_BITS_PER_PKEY));
+
+ __wrpkru(new_pkru);
+
+ dprintf3("%s(pkey=%d, rights=%lx, flags=%lx) = %x pkru now: %x old_pkru: %x\n",
+ __func__, pkey, rights, flags, 0, __rdpkru(), old_pkru);
+ return 0;
+}
+
+void pkey_disable_set(int pkey, int flags)
+{
+ unsigned long syscall_flags = 0;
+ int ret;
+ int pkey_rights;
+ u32 orig_pkru = rdpkru();
+
+ dprintf1("START->%s(%d, 0x%x)\n", __func__,
+ pkey, flags);
+ pkey_assert(flags & (PKEY_DISABLE_ACCESS | PKEY_DISABLE_WRITE));
+
+ pkey_rights = pkey_get(pkey, syscall_flags);
+
+ dprintf1("%s(%d) pkey_get(%d): %x\n", __func__,
+ pkey, pkey, pkey_rights);
+ pkey_assert(pkey_rights >= 0);
+
+ pkey_rights |= flags;
+
+ ret = pkey_set(pkey, pkey_rights, syscall_flags);
+ assert(!ret);
+ /*pkru and flags have the same format */
+ shadow_pkru |= flags << (pkey * 2);
+ dprintf1("%s(%d) shadow: 0x%x\n", __func__, pkey, shadow_pkru);
+
+ pkey_assert(ret >= 0);
+
+ pkey_rights = pkey_get(pkey, syscall_flags);
+ dprintf1("%s(%d) pkey_get(%d): %x\n", __func__,
+ pkey, pkey, pkey_rights);
+
+ dprintf1("%s(%d) pkru: 0x%x\n", __func__, pkey, rdpkru());
+ if (flags)
+ pkey_assert(rdpkru() > orig_pkru);
+ dprintf1("END<---%s(%d, 0x%x)\n", __func__,
+ pkey, flags);
+}
+
+void pkey_disable_clear(int pkey, int flags)
+{
+ unsigned long syscall_flags = 0;
+ int ret;
+ int pkey_rights = pkey_get(pkey, syscall_flags);
+ u32 orig_pkru = rdpkru();
+
+ pkey_assert(flags & (PKEY_DISABLE_ACCESS | PKEY_DISABLE_WRITE));
+
+ dprintf1("%s(%d) pkey_get(%d): %x\n", __func__,
+ pkey, pkey, pkey_rights);
+ pkey_assert(pkey_rights >= 0);
+
+ pkey_rights |= flags;
+
+ ret = pkey_set(pkey, pkey_rights, 0);
+ /* pkru and flags have the same format */
+ shadow_pkru &= ~(flags << (pkey * 2));
+ pkey_assert(ret >= 0);
+
+ pkey_rights = pkey_get(pkey, syscall_flags);
+ dprintf1("%s(%d) pkey_get(%d): %x\n", __func__,
+ pkey, pkey, pkey_rights);
+
+ dprintf1("%s(%d) pkru: 0x%x\n", __func__, pkey, rdpkru());
+ if (flags)
+ assert(rdpkru() > orig_pkru);
+}
+
+void pkey_write_allow(int pkey)
+{
+ pkey_disable_clear(pkey, PKEY_DISABLE_WRITE);
+}
+void pkey_write_deny(int pkey)
+{
+ pkey_disable_set(pkey, PKEY_DISABLE_WRITE);
+}
+void pkey_access_allow(int pkey)
+{
+ pkey_disable_clear(pkey, PKEY_DISABLE_ACCESS);
+}
+void pkey_access_deny(int pkey)
+{
+ pkey_disable_set(pkey, PKEY_DISABLE_ACCESS);
+}
+
+int sys_mprotect_pkey(void *ptr, size_t size, unsigned long orig_prot,
+ unsigned long pkey)
+{
+ int sret;
+
+ dprintf2("%s(0x%p, %zx, prot=%lx, pkey=%lx)\n", __func__,
+ ptr, size, orig_prot, pkey);
+
+ errno = 0;
+ sret = syscall(SYS_mprotect_key, ptr, size, orig_prot, pkey);
+ if (errno) {
+ dprintf2("SYS_mprotect_key sret: %d\n", sret);
+ dprintf2("SYS_mprotect_key prot: 0x%lx\n", orig_prot);
+ dprintf2("SYS_mprotect_key failed, errno: %d\n", errno);
+ if (DEBUG_LEVEL >= 2)
+ perror("SYS_mprotect_pkey");
+ }
+ return sret;
+}
+
+int sys_pkey_alloc(unsigned long flags, unsigned long init_val)
+{
+ int ret = syscall(SYS_pkey_alloc, flags, init_val);
+ dprintf1("%s(flags=%lx, init_val=%lx) syscall ret: %d errno: %d\n",
+ __func__, flags, init_val, ret, errno);
+ return ret;
+}
+
+int alloc_pkey(void)
+{
+ int ret;
+ unsigned long init_val = 0x0;
+
+ dprintf1("alloc_pkey()::%d, pkru: 0x%x shadow: %x\n",
+ __LINE__, __rdpkru(), shadow_pkru);
+ ret = sys_pkey_alloc(0, init_val);
+ /*
+ * pkey_alloc() sets PKRU, so we need to reflect it in
+ * shadow_pkru:
+ */
+ dprintf4("alloc_pkey()::%d, ret: %d pkru: 0x%x shadow: 0x%x\n",
+ __LINE__, ret, __rdpkru(), shadow_pkru);
+ if (ret) {
+ /* clear both the bits: */
+ shadow_pkru &= ~(0x3 << (ret * 2));
+ dprintf4("alloc_pkey()::%d, ret: %d pkru: 0x%x shadow: 0x%x\n",
+ __LINE__, ret, __rdpkru(), shadow_pkru);
+ /*
+ * move the new state in from init_val
+ * (remember, we cheated and init_val == pkru format)
+ */
+ shadow_pkru |= (init_val << (ret * 2));
+ }
+ dprintf4("alloc_pkey()::%d, ret: %d pkru: 0x%x shadow: 0x%x\n",
+ __LINE__, ret, __rdpkru(), shadow_pkru);
+ dprintf1("alloc_pkey()::%d errno: %d\n", __LINE__, errno);
+ /* for shadow checking: */
+ rdpkru();
+ dprintf4("alloc_pkey()::%d, ret: %d pkru: 0x%x shadow: 0x%x\n",
+ __LINE__, ret, __rdpkru(), shadow_pkru);
+ return ret;
+}
+
+int sys_pkey_free(unsigned long pkey)
+{
+ int ret = syscall(SYS_pkey_free, pkey);
+ dprintf1("%s(pkey=%ld) syscall ret: %d\n", __func__, pkey, ret);
+ return ret;
+}
+
+/*
+ * I had a bug where pkey bits could be set by mprotect() but
+ * not cleared. This ensures we get lots of random bit sets
+ * and clears on the vma and pte pkey bits.
+ */
+int alloc_random_pkey(void)
+{
+ int max_nr_pkey_allocs;
+ int ret;
+ int i;
+ int alloced_pkeys[NR_PKEYS];
+ int nr_alloced = 0;
+ int random_index;
+ memset(alloced_pkeys, 0, sizeof(alloced_pkeys));
+
+ /* allocate every possible key and make a note of which ones we got */
+ max_nr_pkey_allocs = NR_PKEYS;
+ max_nr_pkey_allocs = 1;
+ for (i = 0; i < max_nr_pkey_allocs; i++) {
+ int new_pkey = alloc_pkey();
+ if (new_pkey < 0)
+ break;
+ alloced_pkeys[nr_alloced++] = new_pkey;
+ }
+
+ pkey_assert(nr_alloced > 0);
+ /* select a random one out of the allocated ones */
+ random_index = rand() % nr_alloced;
+ ret = alloced_pkeys[random_index];
+ /* now zero it out so we don't free it next */
+ alloced_pkeys[random_index] = 0;
+
+ /* go through the allocated ones that we did not want and free them */
+ for (i = 0; i < nr_alloced; i++) {
+ int free_ret;
+ if (!alloced_pkeys[i])
+ continue;
+ free_ret = sys_pkey_free(alloced_pkeys[i]);
+ pkey_assert(!free_ret);
+ }
+ dprintf1("%s()::%d, ret: %d pkru: 0x%x shadow: 0x%x\n", __func__,
+ __LINE__, ret, __rdpkru(), shadow_pkru);
+ return ret;
+}
+
+int mprotect_pkey(void *ptr, size_t size, unsigned long orig_prot,
+ unsigned long pkey)
+{
+ int nr_iterations = random() % 100;
+ int ret;
+
+ while (0) {
+ int rpkey = alloc_random_pkey();
+ ret = sys_mprotect_pkey(ptr, size, orig_prot, pkey);
+ dprintf1("sys_mprotect_pkey(%p, %zx, prot=0x%lx, pkey=%ld) ret: %d\n",
+ ptr, size, orig_prot, pkey, ret);
+ if (nr_iterations-- < 0)
+ break;
+
+ dprintf1("%s()::%d, ret: %d pkru: 0x%x shadow: 0x%x\n", __func__,
+ __LINE__, ret, __rdpkru(), shadow_pkru);
+ sys_pkey_free(rpkey);
+ dprintf1("%s()::%d, ret: %d pkru: 0x%x shadow: 0x%x\n", __func__,
+ __LINE__, ret, __rdpkru(), shadow_pkru);
+ }
+ pkey_assert(pkey < NR_PKEYS);
+
+ ret = sys_mprotect_pkey(ptr, size, orig_prot, pkey);
+ dprintf1("mprotect_pkey(%p, %zx, prot=0x%lx, pkey=%ld) ret: %d\n",
+ ptr, size, orig_prot, pkey, ret);
+ pkey_assert(!ret);
+ dprintf1("%s()::%d, ret: %d pkru: 0x%x shadow: 0x%x\n", __func__,
+ __LINE__, ret, __rdpkru(), shadow_pkru);
+ return ret;
+}
+
+struct pkey_malloc_record {
+ void *ptr;
+ long size;
+};
+struct pkey_malloc_record *pkey_malloc_records;
+long nr_pkey_malloc_records;
+void record_pkey_malloc(void *ptr, long size)
+{
+ long i;
+ struct pkey_malloc_record *rec = NULL;
+
+ for (i = 0; i < nr_pkey_malloc_records; i++) {
+ rec = &pkey_malloc_records[i];
+ /* find a free record */
+ if (rec)
+ break;
+ }
+ if (!rec) {
+ /* every record is full */
+ size_t old_nr_records = nr_pkey_malloc_records;
+ size_t new_nr_records = (nr_pkey_malloc_records * 2 + 1);
+ size_t new_size = new_nr_records * sizeof(struct pkey_malloc_record);
+ dprintf2("new_nr_records: %zd\n", new_nr_records);
+ dprintf2("new_size: %zd\n", new_size);
+ pkey_malloc_records = realloc(pkey_malloc_records, new_size);
+ pkey_assert(pkey_malloc_records != NULL);
+ rec = &pkey_malloc_records[nr_pkey_malloc_records];
+ /*
+ * realloc() does not initialize memory, so zero it from
+ * the first new record all the way to the end.
+ */
+ for (i = 0; i < new_nr_records - old_nr_records; i++)
+ memset(rec + i, 0, sizeof(*rec));
+ }
+ dprintf3("filling malloc record[%d/%p]: {%p, %ld}\n",
+ (int)(rec - pkey_malloc_records), rec, ptr, size);
+ rec->ptr = ptr;
+ rec->size = size;
+ nr_pkey_malloc_records++;
+}
+
+void free_pkey_malloc(void *ptr)
+{
+ long i;
+ int ret;
+ dprintf3("%s(%p)\n", __func__, ptr);
+ for (i = 0; i < nr_pkey_malloc_records; i++) {
+ struct pkey_malloc_record *rec = &pkey_malloc_records[i];
+ dprintf4("looking for ptr %p at record[%ld/%p]: {%p, %ld}\n",
+ ptr, i, rec, rec->ptr, rec->size);
+ if ((ptr < rec->ptr) ||
+ (ptr >= rec->ptr + rec->size))
+ continue;
+
+ dprintf3("found ptr %p at record[%ld/%p]: {%p, %ld}\n",
+ ptr, i, rec, rec->ptr, rec->size);
+ nr_pkey_malloc_records--;
+ ret = munmap(rec->ptr, rec->size);
+ dprintf3("munmap ret: %d\n", ret);
+ pkey_assert(!ret);
+ dprintf3("clearing rec->ptr, rec: %p\n", rec);
+ rec->ptr = NULL;
+ dprintf3("done clearing rec->ptr, rec: %p\n", rec);
+ return;
+ }
+ pkey_assert(false);
+}
+
+
+void *malloc_pkey_with_mprotect(long size, int prot, u16 pkey)
+{
+ void *ptr;
+ int ret;
+
+ rdpkru();
+ dprintf1("doing %s(size=%ld, prot=0x%x, pkey=%d)\n", __func__,
+ size, prot, pkey);
+ pkey_assert(pkey < NR_PKEYS);
+ ptr = mmap(NULL, size, prot, MAP_ANONYMOUS|MAP_PRIVATE, -1, 0);
+ pkey_assert(ptr != (void *)-1);
+ ret = mprotect_pkey((void *)ptr, PAGE_SIZE, prot, pkey);
+ pkey_assert(!ret);
+ record_pkey_malloc(ptr, size);
+ rdpkru();
+
+ dprintf1("%s() for pkey %d @ %p\n", __func__, pkey, ptr);
+ return ptr;
+}
+
+void *malloc_pkey_anon_huge(long size, int prot, u16 pkey)
+{
+ int ret;
+ void *ptr;
+
+ dprintf1("doing %s(size=%ld, prot=0x%x, pkey=%d)\n", __func__,
+ size, prot, pkey);
+ /*
+ * Guarantee we can fit at least one huge page in the resulting
+ * allocation by allocating space for 2:
+ */
+ size = ALIGN_UP(size, HPAGE_SIZE * 2);
+ ptr = mmap(NULL, size, PROT_NONE, MAP_ANONYMOUS|MAP_PRIVATE, -1, 0);
+ pkey_assert(ptr != (void *)-1);
+ record_pkey_malloc(ptr, size);
+ mprotect_pkey(ptr, size, prot, pkey);
+
+ dprintf1("unaligned ptr: %p\n", ptr);
+ ptr = ALIGN_PTR_UP(ptr, HPAGE_SIZE);
+ dprintf1(" aligned ptr: %p\n", ptr);
+ ret = madvise(ptr, HPAGE_SIZE, MADV_HUGEPAGE);
+ dprintf1("MADV_HUGEPAGE ret: %d\n", ret);
+ ret = madvise(ptr, HPAGE_SIZE, MADV_WILLNEED);
+ dprintf1("MADV_WILLNEED ret: %d\n", ret);
+ memset(ptr, 0, HPAGE_SIZE);
+
+ dprintf1("mmap()'d thp for pkey %d @ %p\n", pkey, ptr);
+ return ptr;
+}
+
+int hugetlb_setup_ok;
+#define GET_NR_HUGE_PAGES 10
+void setup_hugetlbfs(void)
+{
+ int err;
+ int fd;
+ char buf[] = "123";
+
+ if (geteuid() != 0) {
+ fprintf(stderr, "WARNING: not run as root, can not do hugetlb test\n");
+ return;
+ }
+
+ cat_into_file(__stringify(GET_NR_HUGE_PAGES), "/proc/sys/vm/nr_hugepages");
+
+ /*
+ * Now go make sure that we got the pages and that they
+ * are 2M pages. Someone might have made 1G the default.
+ */
+ fd = open("/sys/kernel/mm/hugepages/hugepages-2048kB/nr_hugepages", O_RDONLY);
+ if (fd < 0) {
+ perror("opening sysfs 2M hugetlb config");
+ return;
+ }
+
+ /* -1 to guarantee leaving the trailing \0 */
+ err = read(fd, buf, sizeof(buf)-1);
+ close(fd);
+ if (err <= 0) {
+ perror("reading sysfs 2M hugetlb config");
+ return;
+ }
+
+ if (atoi(buf) != GET_NR_HUGE_PAGES) {
+ fprintf(stderr, "could not confirm 2M pages, got: '%s' expected %d\n",
+ buf, GET_NR_HUGE_PAGES);
+ return;
+ }
+
+ hugetlb_setup_ok = 1;
+}
+
+void *malloc_pkey_hugetlb(long size, int prot, u16 pkey)
+{
+ void *ptr;
+ int flags = MAP_ANONYMOUS|MAP_PRIVATE|MAP_HUGETLB;
+
+ if (!hugetlb_setup_ok)
+ return PTR_ERR_ENOTSUP;
+
+ dprintf1("doing %s(%ld, %x, %x)\n", __func__, size, prot, pkey);
+ size = ALIGN_UP(size, HPAGE_SIZE * 2);
+ pkey_assert(pkey < NR_PKEYS);
+ ptr = mmap(NULL, size, PROT_NONE, flags, -1, 0);
+ pkey_assert(ptr != (void *)-1);
+ mprotect_pkey(ptr, size, prot, pkey);
+
+ record_pkey_malloc(ptr, size);
+
+ dprintf1("mmap()'d hugetlbfs for pkey %d @ %p\n", pkey, ptr);
+ return ptr;
+}
+
+void *malloc_pkey_mmap_dax(long size, int prot, u16 pkey)
+{
+ void *ptr;
+ int fd;
+
+ dprintf1("doing %s(size=%ld, prot=0x%x, pkey=%d)\n", __func__,
+ size, prot, pkey);
+ pkey_assert(pkey < NR_PKEYS);
+ fd = open("/dax/foo", O_RDWR);
+ pkey_assert(fd >= 0);
+
+ ptr = mmap(0, size, prot, MAP_SHARED, fd, 0);
+ pkey_assert(ptr != (void *)-1);
+
+ mprotect_pkey(ptr, size, prot, pkey);
+
+ record_pkey_malloc(ptr, size);
+
+ dprintf1("mmap()'d for pkey %d @ %p\n", pkey, ptr);
+ close(fd);
+ return ptr;
+}
+
+void *(*pkey_malloc[])(long size, int prot, u16 pkey) = {
+
+ malloc_pkey_with_mprotect,
+ malloc_pkey_anon_huge,
+ malloc_pkey_hugetlb
+/* can not do direct with the pkey_mprotect() API:
+ malloc_pkey_mmap_direct,
+ malloc_pkey_mmap_dax,
+*/
+};
+
+void *malloc_pkey(long size, int prot, u16 pkey)
+{
+ void *ret;
+ static int malloc_type;
+ int nr_malloc_types = ARRAY_SIZE(pkey_malloc);
+
+ pkey_assert(pkey < NR_PKEYS);
+
+ while (1) {
+ pkey_assert(malloc_type < nr_malloc_types);
+
+ ret = pkey_malloc[malloc_type](size, prot, pkey);
+ pkey_assert(ret != (void *)-1);
+
+ malloc_type++;
+ if (malloc_type >= nr_malloc_types)
+ malloc_type = (random()%nr_malloc_types);
+
+ /* try again if the malloc_type we tried is unsupported */
+ if (ret == PTR_ERR_ENOTSUP)
+ continue;
+
+ break;
+ }
+
+ dprintf3("%s(%ld, prot=%x, pkey=%x) returning: %p\n", __func__,
+ size, prot, pkey, ret);
+ return ret;
+}
+
+int last_pkru_faults;
+void expected_pk_fault(int pkey)
+{
+ dprintf2("%s(): last_pkru_faults: %d pkru_faults: %d\n",
+ __func__, last_pkru_faults, pkru_faults);
+ dprintf2("%s(%d): last_si_pkey: %d\n", __func__, pkey, last_si_pkey);
+ pkey_assert(last_pkru_faults + 1 == pkru_faults);
+ pkey_assert(last_si_pkey == pkey);
+ /*
+ * The signal handler shold have cleared out PKRU to let the
+ * test program continue. We now have to restore it.
+ */
+ if (__rdpkru() != 0)
+ pkey_assert(0);
+
+ __wrpkru(shadow_pkru);
+ dprintf1("%s() set PKRU=%x to restore state after signal nuked it\n",
+ __func__, shadow_pkru);
+ last_pkru_faults = pkru_faults;
+ last_si_pkey = -1;
+}
+
+void do_not_expect_pk_fault(void)
+{
+ pkey_assert(last_pkru_faults == pkru_faults);
+}
+
+int test_fds[10] = { -1 };
+int nr_test_fds;
+void __save_test_fd(int fd)
+{
+ pkey_assert(fd >= 0);
+ pkey_assert(nr_test_fds < ARRAY_SIZE(test_fds));
+ test_fds[nr_test_fds] = fd;
+ nr_test_fds++;
+}
+
+int get_test_read_fd(void)
+{
+ int test_fd = open("/etc/passwd", O_RDONLY);
+ __save_test_fd(test_fd);
+ return test_fd;
+}
+
+void close_test_fds(void)
+{
+ int i;
+
+ for (i = 0; i < nr_test_fds; i++) {
+ if (test_fds[i] < 0)
+ continue;
+ close(test_fds[i]);
+ test_fds[i] = -1;
+ }
+ nr_test_fds = 0;
+}
+
+#define barrier() __asm__ __volatile__("": : :"memory")
+__attribute__((noinline)) int read_ptr(int *ptr)
+{
+ /*
+ * Keep GCC from optimizing this away somehow
+ */
+ barrier();
+ return *ptr;
+}
+
+void test_read_of_write_disabled_region(int *ptr, u16 pkey)
+{
+ int ptr_contents;
+
+ dprintf1("disabling write access to PKEY[1], doing read\n");
+ pkey_write_deny(pkey);
+ ptr_contents = read_ptr(ptr);
+ dprintf1("*ptr: %d\n", ptr_contents);
+ dprintf1("\n");
+}
+void test_read_of_access_disabled_region(int *ptr, u16 pkey)
+{
+ int ptr_contents;
+
+ dprintf1("disabling access to PKEY[%02d], doing read @ %p\n", pkey, ptr);
+ rdpkru();
+ pkey_access_deny(pkey);
+ ptr_contents = read_ptr(ptr);
+ dprintf1("*ptr: %d\n", ptr_contents);
+ expected_pk_fault(pkey);
+}
+void test_write_of_write_disabled_region(int *ptr, u16 pkey)
+{
+ dprintf1("disabling write access to PKEY[%02d], doing write\n", pkey);
+ pkey_write_deny(pkey);
+ *ptr = __LINE__;
+ expected_pk_fault(pkey);
+}
+void test_write_of_access_disabled_region(int *ptr, u16 pkey)
+{
+ dprintf1("disabling access to PKEY[%02d], doing write\n", pkey);
+ pkey_access_deny(pkey);
+ *ptr = __LINE__;
+ expected_pk_fault(pkey);
+}
+void test_kernel_write_of_access_disabled_region(int *ptr, u16 pkey)
+{
+ int ret;
+ int test_fd = get_test_read_fd();
+
+ dprintf1("disabling access to PKEY[%02d], "
+ "having kernel read() to buffer\n", pkey);
+ pkey_access_deny(pkey);
+ ret = read(test_fd, ptr, 1);
+ dprintf1("read ret: %d\n", ret);
+ pkey_assert(ret);
+}
+void test_kernel_write_of_write_disabled_region(int *ptr, u16 pkey)
+{
+ int ret;
+ int test_fd = get_test_read_fd();
+
+ pkey_write_deny(pkey);
+ ret = read(test_fd, ptr, 100);
+ dprintf1("read ret: %d\n", ret);
+ if (ret < 0 && (DEBUG_LEVEL > 0))
+ perror("verbose read result (OK for this to be bad)");
+ pkey_assert(ret);
+}
+
+void test_kernel_gup_of_access_disabled_region(int *ptr, u16 pkey)
+{
+ int pipe_ret, vmsplice_ret;
+ struct iovec iov;
+ int pipe_fds[2];
+
+ pipe_ret = pipe(pipe_fds);
+
+ pkey_assert(pipe_ret == 0);
+ dprintf1("disabling access to PKEY[%02d], "
+ "having kernel vmsplice from buffer\n", pkey);
+ pkey_access_deny(pkey);
+ iov.iov_base = ptr;
+ iov.iov_len = PAGE_SIZE;
+ vmsplice_ret = vmsplice(pipe_fds[1], &iov, 1, SPLICE_F_GIFT);
+ dprintf1("vmsplice() ret: %d\n", vmsplice_ret);
+ pkey_assert(vmsplice_ret == -1);
+
+ close(pipe_fds[0]);
+ close(pipe_fds[1]);
+}
+
+void test_kernel_gup_write_to_write_disabled_region(int *ptr, u16 pkey)
+{
+ int ignored = 0xdada;
+ int futex_ret;
+ int some_int = __LINE__;
+
+ dprintf1("disabling write to PKEY[%02d], "
+ "doing futex gunk in buffer\n", pkey);
+ *ptr = some_int;
+ pkey_write_deny(pkey);
+ futex_ret = syscall(SYS_futex, ptr, FUTEX_WAIT, some_int-1, NULL,
+ &ignored, ignored);
+ if (DEBUG_LEVEL > 0)
+ perror("futex");
+ dprintf1("futex() ret: %d\n", futex_ret);
+}
+
+/* Assumes that all pkeys other than 'pkey' are unallocated */
+void test_pkey_syscalls_on_non_allocated_pkey(int *ptr, u16 pkey)
+{
+ int err;
+ int i;
+
+ /* Note: 0 is the default pkey, so don't mess with it */
+ for (i = 1; i < NR_PKEYS; i++) {
+ if (pkey == i)
+ continue;
+
+ dprintf1("trying get/set/free to non-allocated pkey: %2d\n", i);
+ err = sys_pkey_free(i);
+ pkey_assert(err);
+
+ err = sys_pkey_free(i);
+ pkey_assert(err);
+
+ err = sys_mprotect_pkey(ptr, PAGE_SIZE, PROT_READ, i);
+ pkey_assert(err);
+ }
+}
+
+/* Assumes that all pkeys other than 'pkey' are unallocated */
+void test_pkey_syscalls_bad_args(int *ptr, u16 pkey)
+{
+ int err;
+ int bad_pkey = NR_PKEYS+99;
+
+ /* pass a known-invalid pkey in: */
+ err = sys_mprotect_pkey(ptr, PAGE_SIZE, PROT_READ, bad_pkey);
+ pkey_assert(err);
+}
+
+/* Assumes that all pkeys other than 'pkey' are unallocated */
+void test_pkey_alloc_exhaust(int *ptr, u16 pkey)
+{
+ int err;
+ int allocated_pkeys[NR_PKEYS] = {0};
+ int nr_allocated_pkeys = 0;
+ int i;
+
+ for (i = 0; i < NR_PKEYS*2; i++) {
+ int new_pkey;
+ dprintf1("%s() alloc loop: %d\n", __func__, i);
+ new_pkey = alloc_pkey();
+ dprintf4("%s()::%d, err: %d pkru: 0x%x shadow: 0x%x\n", __func__,
+ __LINE__, err, __rdpkru(), shadow_pkru);
+ rdpkru(); /* for shadow checking */
+ dprintf2("%s() errno: %d ENOSPC: %d\n", __func__, errno, ENOSPC);
+ if ((new_pkey == -1) && (errno == ENOSPC)) {
+ dprintf2("%s() failed to allocate pkey after %d tries\n",
+ __func__, nr_allocated_pkeys);
+ break;
+ }
+ pkey_assert(nr_allocated_pkeys < NR_PKEYS);
+ allocated_pkeys[nr_allocated_pkeys++] = new_pkey;
+ }
+
+ dprintf3("%s()::%d\n", __func__, __LINE__);
+
+ /*
+ * ensure it did not reach the end of the loop without
+ * failure:
+ */
+ pkey_assert(i < NR_PKEYS*2);
+
+ /*
+ * There are 16 pkeys supported in hardware. One is taken
+ * up for the default (0) and another can be taken up by
+ * an execute-only mapping. Ensure that we can allocate
+ * at least 14 (16-2).
+ */
+ pkey_assert(i >= NR_PKEYS-2);
+
+ for (i = 0; i < nr_allocated_pkeys; i++) {
+ err = sys_pkey_free(allocated_pkeys[i]);
+ pkey_assert(!err);
+ rdpkru(); /* for shadow checking */
+ }
+}
+
+void test_ptrace_of_child(int *ptr, u16 pkey)
+{
+ __attribute__((__unused__)) int peek_result;
+ pid_t child_pid;
+ void *ignored = 0;
+ long ret;
+ int status;
+ /*
+ * This is the "control" for our little expermient. Make sure
+ * we can always access it when ptracing.
+ */
+ int *plain_ptr_unaligned = malloc(HPAGE_SIZE);
+ int *plain_ptr = ALIGN_PTR_UP(plain_ptr_unaligned, PAGE_SIZE);
+
+ /*
+ * Fork a child which is an exact copy of this process, of course.
+ * That means we can do all of our tests via ptrace() and then plain
+ * memory access and ensure they work differently.
+ */
+ child_pid = fork_lazy_child();
+ dprintf1("[%d] child pid: %d\n", getpid(), child_pid);
+
+ ret = ptrace(PTRACE_ATTACH, child_pid, ignored, ignored);
+ if (ret)
+ perror("attach");
+ dprintf1("[%d] attach ret: %ld %d\n", getpid(), ret, __LINE__);
+ pkey_assert(ret != -1);
+ ret = waitpid(child_pid, &status, WUNTRACED);
+ if ((ret != child_pid) || !(WIFSTOPPED(status))) {
+ fprintf(stderr, "weird waitpid result %ld stat %x\n",
+ ret, status);
+ pkey_assert(0);
+ }
+ dprintf2("waitpid ret: %ld\n", ret);
+ dprintf2("waitpid status: %d\n", status);
+
+ pkey_access_deny(pkey);
+ pkey_write_deny(pkey);
+
+ /* Write access, untested for now:
+ ret = ptrace(PTRACE_POKEDATA, child_pid, peek_at, data);
+ pkey_assert(ret != -1);
+ dprintf1("poke at %p: %ld\n", peek_at, ret);
+ */
+
+ /*
+ * Try to access the pkey-protected "ptr" via ptrace:
+ */
+ ret = ptrace(PTRACE_PEEKDATA, child_pid, ptr, ignored);
+ /* expect it to work, without an error: */
+ pkey_assert(ret != -1);
+ /* Now access from the current task, and expect an exception: */
+ peek_result = read_ptr(ptr);
+ expected_pk_fault(pkey);
+
+ /*
+ * Try to access the NON-pkey-protected "plain_ptr" via ptrace:
+ */
+ ret = ptrace(PTRACE_PEEKDATA, child_pid, plain_ptr, ignored);
+ /* expect it to work, without an error: */
+ pkey_assert(ret != -1);
+ /* Now access from the current task, and expect NO exception: */
+ peek_result = read_ptr(plain_ptr);
+ do_not_expect_pk_fault();
+
+ ret = ptrace(PTRACE_DETACH, child_pid, ignored, 0);
+ pkey_assert(ret != -1);
+
+ ret = kill(child_pid, SIGKILL);
+ pkey_assert(ret != -1);
+
+ wait(&status);
+
+ free(plain_ptr_unaligned);
+}
+
+void test_executing_on_unreadable_memory(int *ptr, u16 pkey)
+{
+ void *p1;
+ int scratch;
+ int ptr_contents;
+ int ret;
+
+ p1 = ALIGN_PTR_UP(&lots_o_noops_around_write, PAGE_SIZE);
+ dprintf3("&lots_o_noops: %p\n", &lots_o_noops_around_write);
+ /* lots_o_noops_around_write should be page-aligned already */
+ assert(p1 == &lots_o_noops_around_write);
+
+ /* Point 'p1' at the *second* page of the function: */
+ p1 += PAGE_SIZE;
+
+ madvise(p1, PAGE_SIZE, MADV_DONTNEED);
+ lots_o_noops_around_write(&scratch);
+ ptr_contents = read_ptr(p1);
+ dprintf2("ptr (%p) contents@%d: %x\n", p1, __LINE__, ptr_contents);
+
+ ret = mprotect_pkey(p1, PAGE_SIZE, PROT_EXEC, (u64)pkey);
+ pkey_assert(!ret);
+ pkey_access_deny(pkey);
+
+ dprintf2("pkru: %x\n", rdpkru());
+
+ /*
+ * Make sure this is an *instruction* fault
+ */
+ madvise(p1, PAGE_SIZE, MADV_DONTNEED);
+ lots_o_noops_around_write(&scratch);
+ do_not_expect_pk_fault();
+ ptr_contents = read_ptr(p1);
+ dprintf2("ptr (%p) contents@%d: %x\n", p1, __LINE__, ptr_contents);
+ expected_pk_fault(pkey);
+}
+
+void test_mprotect_pkey_on_unsupported_cpu(int *ptr, u16 pkey)
+{
+ int size = PAGE_SIZE;
+ int sret;
+
+ if (cpu_has_pku()) {
+ dprintf1("SKIP: %s: no CPU support\n", __func__);
+ return;
+ }
+
+ sret = syscall(SYS_mprotect_key, ptr, size, PROT_READ, pkey);
+ pkey_assert(sret < 0);
+}
+
+void (*pkey_tests[])(int *ptr, u16 pkey) = {
+ test_read_of_write_disabled_region,
+ test_read_of_access_disabled_region,
+ test_write_of_write_disabled_region,
+ test_write_of_access_disabled_region,
+ test_kernel_write_of_access_disabled_region,
+ test_kernel_write_of_write_disabled_region,
+ test_kernel_gup_of_access_disabled_region,
+ test_kernel_gup_write_to_write_disabled_region,
+ test_executing_on_unreadable_memory,
+ test_ptrace_of_child,
+ test_pkey_syscalls_on_non_allocated_pkey,
+ test_pkey_syscalls_bad_args,
+ test_pkey_alloc_exhaust,
+};
+
+void run_tests_once(void)
+{
+ int *ptr;
+ int prot = PROT_READ|PROT_WRITE;
+
+ for (test_nr = 0; test_nr < ARRAY_SIZE(pkey_tests); test_nr++) {
+ int pkey;
+ int orig_pkru_faults = pkru_faults;
+
+ dprintf1("======================\n");
+ dprintf1("test %d preparing...\n", test_nr);
+
+ tracing_on();
+ pkey = alloc_random_pkey();
+ dprintf1("test %d starting with pkey: %d\n", test_nr, pkey);
+ ptr = malloc_pkey(PAGE_SIZE, prot, pkey);
+ dprintf1("test %d starting...\n", test_nr);
+ pkey_tests[test_nr](ptr, pkey);
+ dprintf1("freeing test memory: %p\n", ptr);
+ free_pkey_malloc(ptr);
+ sys_pkey_free(pkey);
+
+ dprintf1("pkru_faults: %d\n", pkru_faults);
+ dprintf1("orig_pkru_faults: %d\n", orig_pkru_faults);
+
+ tracing_off();
+ close_test_fds();
+
+ printf("test %2d PASSED (iteration %d)\n", test_nr, iteration_nr);
+ dprintf1("======================\n\n");
+ }
+ iteration_nr++;
+}
+
+void pkey_setup_shadow(void)
+{
+ shadow_pkru = __rdpkru();
+}
+
+int main(void)
+{
+ int nr_iterations = 22;
+
+ setup_handlers();
+
+ printf("has pku: %d\n", cpu_has_pku());
+
+ if (!cpu_has_pku()) {
+ int size = PAGE_SIZE;
+ int *ptr;
+
+ printf("running PKEY tests for unsupported CPU/OS\n");
+
+ ptr = mmap(NULL, size, PROT_NONE, MAP_ANONYMOUS|MAP_PRIVATE, -1, 0);
+ assert(ptr != (void *)-1);
+ test_mprotect_pkey_on_unsupported_cpu(ptr, 1);
+ exit(0);
+ }
+
+ pkey_setup_shadow();
+ printf("startup pkru: %x\n", rdpkru());
+ setup_hugetlbfs();
+
+ while (nr_iterations-- > 0)
+ run_tests_once();
+
+ printf("done (all tests OK)\n");
+ return 0;
+}
diff --git a/tools/testing/selftests/x86/Makefile b/tools/testing/selftests/x86/Makefile
index 97f187e..fee6181 100644
--- a/tools/testing/selftests/x86/Makefile
+++ b/tools/testing/selftests/x86/Makefile
@@ -6,7 +6,7 @@ include ../lib.mk

TARGETS_C_BOTHBITS := single_step_syscall sysret_ss_attrs syscall_nt ptrace_syscall test_mremap_vdso \
check_initial_reg_state sigreturn ldt_gdt iopl mpx-mini-test ioperm \
- protection_keys test_vdso
+ test_vdso
TARGETS_C_32BIT_ONLY := entry_from_vm86 syscall_arg_fault test_syscall_vdso unwind_vdso \
test_FCMOV test_FCOMI test_FISTTP \
vdso_restorer
diff --git a/tools/testing/selftests/x86/pkey-helpers.h b/tools/testing/selftests/x86/pkey-helpers.h
deleted file mode 100644
index b202939..0000000
--- a/tools/testing/selftests/x86/pkey-helpers.h
+++ /dev/null
@@ -1,219 +0,0 @@
-#ifndef _PKEYS_HELPER_H
-#define _PKEYS_HELPER_H
-#define _GNU_SOURCE
-#include <string.h>
-#include <stdarg.h>
-#include <stdio.h>
-#include <stdint.h>
-#include <stdbool.h>
-#include <signal.h>
-#include <assert.h>
-#include <stdlib.h>
-#include <ucontext.h>
-#include <sys/mman.h>
-
-#define NR_PKEYS 16
-#define PKRU_BITS_PER_PKEY 2
-
-#ifndef DEBUG_LEVEL
-#define DEBUG_LEVEL 0
-#endif
-#define DPRINT_IN_SIGNAL_BUF_SIZE 4096
-extern int dprint_in_signal;
-extern char dprint_in_signal_buffer[DPRINT_IN_SIGNAL_BUF_SIZE];
-static inline void sigsafe_printf(const char *format, ...)
-{
- va_list ap;
-
- va_start(ap, format);
- if (!dprint_in_signal) {
- vprintf(format, ap);
- } else {
- int len = vsnprintf(dprint_in_signal_buffer,
- DPRINT_IN_SIGNAL_BUF_SIZE,
- format, ap);
- /*
- * len is amount that would have been printed,
- * but actual write is truncated at BUF_SIZE.
- */
- if (len > DPRINT_IN_SIGNAL_BUF_SIZE)
- len = DPRINT_IN_SIGNAL_BUF_SIZE;
- write(1, dprint_in_signal_buffer, len);
- }
- va_end(ap);
-}
-#define dprintf_level(level, args...) do { \
- if (level <= DEBUG_LEVEL) \
- sigsafe_printf(args); \
- fflush(NULL); \
-} while (0)
-#define dprintf0(args...) dprintf_level(0, args)
-#define dprintf1(args...) dprintf_level(1, args)
-#define dprintf2(args...) dprintf_level(2, args)
-#define dprintf3(args...) dprintf_level(3, args)
-#define dprintf4(args...) dprintf_level(4, args)
-
-extern unsigned int shadow_pkru;
-static inline unsigned int __rdpkru(void)
-{
- unsigned int eax, edx;
- unsigned int ecx = 0;
- unsigned int pkru;
-
- asm volatile(".byte 0x0f,0x01,0xee\n\t"
- : "=a" (eax), "=d" (edx)
- : "c" (ecx));
- pkru = eax;
- return pkru;
-}
-
-static inline unsigned int _rdpkru(int line)
-{
- unsigned int pkru = __rdpkru();
-
- dprintf4("rdpkru(line=%d) pkru: %x shadow: %x\n",
- line, pkru, shadow_pkru);
- assert(pkru == shadow_pkru);
-
- return pkru;
-}
-
-#define rdpkru() _rdpkru(__LINE__)
-
-static inline void __wrpkru(unsigned int pkru)
-{
- unsigned int eax = pkru;
- unsigned int ecx = 0;
- unsigned int edx = 0;
-
- dprintf4("%s() changing %08x to %08x\n", __func__, __rdpkru(), pkru);
- asm volatile(".byte 0x0f,0x01,0xef\n\t"
- : : "a" (eax), "c" (ecx), "d" (edx));
- assert(pkru == __rdpkru());
-}
-
-static inline void wrpkru(unsigned int pkru)
-{
- dprintf4("%s() changing %08x to %08x\n", __func__, __rdpkru(), pkru);
- /* will do the shadow check for us: */
- rdpkru();
- __wrpkru(pkru);
- shadow_pkru = pkru;
- dprintf4("%s(%08x) pkru: %08x\n", __func__, pkru, __rdpkru());
-}
-
-/*
- * These are technically racy. since something could
- * change PKRU between the read and the write.
- */
-static inline void __pkey_access_allow(int pkey, int do_allow)
-{
- unsigned int pkru = rdpkru();
- int bit = pkey * 2;
-
- if (do_allow)
- pkru &= (1<<bit);
- else
- pkru |= (1<<bit);
-
- dprintf4("pkru now: %08x\n", rdpkru());
- wrpkru(pkru);
-}
-
-static inline void __pkey_write_allow(int pkey, int do_allow_write)
-{
- long pkru = rdpkru();
- int bit = pkey * 2 + 1;
-
- if (do_allow_write)
- pkru &= (1<<bit);
- else
- pkru |= (1<<bit);
-
- wrpkru(pkru);
- dprintf4("pkru now: %08x\n", rdpkru());
-}
-
-#define PROT_PKEY0 0x10 /* protection key value (bit 0) */
-#define PROT_PKEY1 0x20 /* protection key value (bit 1) */
-#define PROT_PKEY2 0x40 /* protection key value (bit 2) */
-#define PROT_PKEY3 0x80 /* protection key value (bit 3) */
-
-#define PAGE_SIZE 4096
-#define MB (1<<20)
-
-static inline void __cpuid(unsigned int *eax, unsigned int *ebx,
- unsigned int *ecx, unsigned int *edx)
-{
- /* ecx is often an input as well as an output. */
- asm volatile(
- "cpuid;"
- : "=a" (*eax),
- "=b" (*ebx),
- "=c" (*ecx),
- "=d" (*edx)
- : "0" (*eax), "2" (*ecx));
-}
-
-/* Intel-defined CPU features, CPUID level 0x00000007:0 (ecx) */
-#define X86_FEATURE_PKU (1<<3) /* Protection Keys for Userspace */
-#define X86_FEATURE_OSPKE (1<<4) /* OS Protection Keys Enable */
-
-static inline int cpu_has_pku(void)
-{
- unsigned int eax;
- unsigned int ebx;
- unsigned int ecx;
- unsigned int edx;
-
- eax = 0x7;
- ecx = 0x0;
- __cpuid(&eax, &ebx, &ecx, &edx);
-
- if (!(ecx & X86_FEATURE_PKU)) {
- dprintf2("cpu does not have PKU\n");
- return 0;
- }
- if (!(ecx & X86_FEATURE_OSPKE)) {
- dprintf2("cpu does not have OSPKE\n");
- return 0;
- }
- return 1;
-}
-
-#define XSTATE_PKRU_BIT (9)
-#define XSTATE_PKRU 0x200
-
-int pkru_xstate_offset(void)
-{
- unsigned int eax;
- unsigned int ebx;
- unsigned int ecx;
- unsigned int edx;
- int xstate_offset;
- int xstate_size;
- unsigned long XSTATE_CPUID = 0xd;
- int leaf;
-
- /* assume that XSTATE_PKRU is set in XCR0 */
- leaf = XSTATE_PKRU_BIT;
- {
- eax = XSTATE_CPUID;
- ecx = leaf;
- __cpuid(&eax, &ebx, &ecx, &edx);
-
- if (leaf == XSTATE_PKRU_BIT) {
- xstate_offset = ebx;
- xstate_size = eax;
- }
- }
-
- if (xstate_size == 0) {
- printf("could not find size/offset of PKRU in xsave state\n");
- return 0;
- }
-
- return xstate_offset;
-}
-
-#endif /* _PKEYS_HELPER_H */
diff --git a/tools/testing/selftests/x86/protection_keys.c b/tools/testing/selftests/x86/protection_keys.c
deleted file mode 100644
index 3237bc0..0000000
--- a/tools/testing/selftests/x86/protection_keys.c
+++ /dev/null
@@ -1,1395 +0,0 @@
-/*
- * Tests x86 Memory Protection Keys (see Documentation/x86/protection-keys.txt)
- *
- * There are examples in here of:
- * * how to set protection keys on memory
- * * how to set/clear bits in PKRU (the rights register)
- * * how to handle SEGV_PKRU signals and extract pkey-relevant
- * information from the siginfo
- *
- * Things to add:
- * make sure KSM and KSM COW breaking works
- * prefault pages in at malloc, or not
- * protect MPX bounds tables with protection keys?
- * make sure VMA splitting/merging is working correctly
- * OOMs can destroy mm->mmap (see exit_mmap()), so make sure it is immune to pkeys
- * look for pkey "leaks" where it is still set on a VMA but "freed" back to the kernel
- * do a plain mprotect() to a mprotect_pkey() area and make sure the pkey sticks
- *
- * Compile like this:
- * gcc -o protection_keys -O2 -g -std=gnu99 -pthread -Wall protection_keys.c -lrt -ldl -lm
- * gcc -m32 -o protection_keys_32 -O2 -g -std=gnu99 -pthread -Wall protection_keys.c -lrt -ldl -lm
- */
-#define _GNU_SOURCE
-#include <errno.h>
-#include <linux/futex.h>
-#include <sys/time.h>
-#include <sys/syscall.h>
-#include <string.h>
-#include <stdio.h>
-#include <stdint.h>
-#include <stdbool.h>
-#include <signal.h>
-#include <assert.h>
-#include <stdlib.h>
-#include <ucontext.h>
-#include <sys/mman.h>
-#include <sys/types.h>
-#include <sys/wait.h>
-#include <sys/stat.h>
-#include <fcntl.h>
-#include <unistd.h>
-#include <sys/ptrace.h>
-#include <setjmp.h>
-
-#include "pkey-helpers.h"
-
-int iteration_nr = 1;
-int test_nr;
-
-unsigned int shadow_pkru;
-
-#define HPAGE_SIZE (1UL<<21)
-#define ARRAY_SIZE(x) (sizeof(x) / sizeof(*(x)))
-#define ALIGN_UP(x, align_to) (((x) + ((align_to)-1)) & ~((align_to)-1))
-#define ALIGN_DOWN(x, align_to) ((x) & ~((align_to)-1))
-#define ALIGN_PTR_UP(p, ptr_align_to) ((typeof(p))ALIGN_UP((unsigned long)(p), ptr_align_to))
-#define ALIGN_PTR_DOWN(p, ptr_align_to) ((typeof(p))ALIGN_DOWN((unsigned long)(p), ptr_align_to))
-#define __stringify_1(x...) #x
-#define __stringify(x...) __stringify_1(x)
-
-#define PTR_ERR_ENOTSUP ((void *)-ENOTSUP)
-
-int dprint_in_signal;
-char dprint_in_signal_buffer[DPRINT_IN_SIGNAL_BUF_SIZE];
-
-extern void abort_hooks(void);
-#define pkey_assert(condition) do { \
- if (!(condition)) { \
- dprintf0("assert() at %s::%d test_nr: %d iteration: %d\n", \
- __FILE__, __LINE__, \
- test_nr, iteration_nr); \
- dprintf0("errno at assert: %d", errno); \
- abort_hooks(); \
- assert(condition); \
- } \
-} while (0)
-#define raw_assert(cond) assert(cond)
-
-void cat_into_file(char *str, char *file)
-{
- int fd = open(file, O_RDWR);
- int ret;
-
- dprintf2("%s(): writing '%s' to '%s'\n", __func__, str, file);
- /*
- * these need to be raw because they are called under
- * pkey_assert()
- */
- raw_assert(fd >= 0);
- ret = write(fd, str, strlen(str));
- if (ret != strlen(str)) {
- perror("write to file failed");
- fprintf(stderr, "filename: '%s' str: '%s'\n", file, str);
- raw_assert(0);
- }
- close(fd);
-}
-
-#if CONTROL_TRACING > 0
-static int warned_tracing;
-int tracing_root_ok(void)
-{
- if (geteuid() != 0) {
- if (!warned_tracing)
- fprintf(stderr, "WARNING: not run as root, "
- "can not do tracing control\n");
- warned_tracing = 1;
- return 0;
- }
- return 1;
-}
-#endif
-
-void tracing_on(void)
-{
-#if CONTROL_TRACING > 0
-#define TRACEDIR "/sys/kernel/debug/tracing"
- char pidstr[32];
-
- if (!tracing_root_ok())
- return;
-
- sprintf(pidstr, "%d", getpid());
- cat_into_file("0", TRACEDIR "/tracing_on");
- cat_into_file("\n", TRACEDIR "/trace");
- if (1) {
- cat_into_file("function_graph", TRACEDIR "/current_tracer");
- cat_into_file("1", TRACEDIR "/options/funcgraph-proc");
- } else {
- cat_into_file("nop", TRACEDIR "/current_tracer");
- }
- cat_into_file(pidstr, TRACEDIR "/set_ftrace_pid");
- cat_into_file("1", TRACEDIR "/tracing_on");
- dprintf1("enabled tracing\n");
-#endif
-}
-
-void tracing_off(void)
-{
-#if CONTROL_TRACING > 0
- if (!tracing_root_ok())
- return;
- cat_into_file("0", "/sys/kernel/debug/tracing/tracing_on");
-#endif
-}
-
-void abort_hooks(void)
-{
- fprintf(stderr, "running %s()...\n", __func__);
- tracing_off();
-#ifdef SLEEP_ON_ABORT
- sleep(SLEEP_ON_ABORT);
-#endif
-}
-
-static inline void __page_o_noops(void)
-{
- /* 8-bytes of instruction * 512 bytes = 1 page */
- asm(".rept 512 ; nopl 0x7eeeeeee(%eax) ; .endr");
-}
-
-/*
- * This attempts to have roughly a page of instructions followed by a few
- * instructions that do a write, and another page of instructions. That
- * way, we are pretty sure that the write is in the second page of
- * instructions and has at least a page of padding behind it.
- *
- * *That* lets us be sure to madvise() away the write instruction, which
- * will then fault, which makes sure that the fault code handles
- * execute-only memory properly.
- */
-__attribute__((__aligned__(PAGE_SIZE)))
-void lots_o_noops_around_write(int *write_to_me)
-{
- dprintf3("running %s()\n", __func__);
- __page_o_noops();
- /* Assume this happens in the second page of instructions: */
- *write_to_me = __LINE__;
- /* pad out by another page: */
- __page_o_noops();
- dprintf3("%s() done\n", __func__);
-}
-
-/* Define some kernel-like types */
-#define u8 uint8_t
-#define u16 uint16_t
-#define u32 uint32_t
-#define u64 uint64_t
-
-#ifdef __i386__
-#define SYS_mprotect_key 380
-#define SYS_pkey_alloc 381
-#define SYS_pkey_free 382
-#define REG_IP_IDX REG_EIP
-#define si_pkey_offset 0x14
-#else
-#define SYS_mprotect_key 329
-#define SYS_pkey_alloc 330
-#define SYS_pkey_free 331
-#define REG_IP_IDX REG_RIP
-#define si_pkey_offset 0x20
-#endif
-
-void dump_mem(void *dumpme, int len_bytes)
-{
- char *c = (void *)dumpme;
- int i;
-
- for (i = 0; i < len_bytes; i += sizeof(u64)) {
- u64 *ptr = (u64 *)(c + i);
- dprintf1("dump[%03d][@%p]: %016jx\n", i, ptr, *ptr);
- }
-}
-
-#define __SI_FAULT (3 << 16)
-#define SEGV_BNDERR (__SI_FAULT|3) /* failed address bound checks */
-#define SEGV_PKUERR (__SI_FAULT|4)
-
-static char *si_code_str(int si_code)
-{
- if (si_code & SEGV_MAPERR)
- return "SEGV_MAPERR";
- if (si_code & SEGV_ACCERR)
- return "SEGV_ACCERR";
- if (si_code & SEGV_BNDERR)
- return "SEGV_BNDERR";
- if (si_code & SEGV_PKUERR)
- return "SEGV_PKUERR";
- return "UNKNOWN";
-}
-
-int pkru_faults;
-int last_si_pkey = -1;
-void signal_handler(int signum, siginfo_t *si, void *vucontext)
-{
- ucontext_t *uctxt = vucontext;
- int trapno;
- unsigned long ip;
- char *fpregs;
- u32 *pkru_ptr;
- u64 si_pkey;
- u32 *si_pkey_ptr;
- int pkru_offset;
- fpregset_t fpregset;
-
- dprint_in_signal = 1;
- dprintf1(">>>>===============SIGSEGV============================\n");
- dprintf1("%s()::%d, pkru: 0x%x shadow: %x\n", __func__, __LINE__,
- __rdpkru(), shadow_pkru);
-
- trapno = uctxt->uc_mcontext.gregs[REG_TRAPNO];
- ip = uctxt->uc_mcontext.gregs[REG_IP_IDX];
- fpregset = uctxt->uc_mcontext.fpregs;
- fpregs = (void *)fpregset;
-
- dprintf2("%s() trapno: %d ip: 0x%lx info->si_code: %s/%d\n", __func__,
- trapno, ip, si_code_str(si->si_code), si->si_code);
-#ifdef __i386__
- /*
- * 32-bit has some extra padding so that userspace can tell whether
- * the XSTATE header is present in addition to the "legacy" FPU
- * state. We just assume that it is here.
- */
- fpregs += 0x70;
-#endif
- pkru_offset = pkru_xstate_offset();
- pkru_ptr = (void *)(&fpregs[pkru_offset]);
-
- dprintf1("siginfo: %p\n", si);
- dprintf1(" fpregs: %p\n", fpregs);
- /*
- * If we got a PKRU fault, we *HAVE* to have at least one bit set in
- * here.
- */
- dprintf1("pkru_xstate_offset: %d\n", pkru_xstate_offset());
- if (DEBUG_LEVEL > 4)
- dump_mem(pkru_ptr - 128, 256);
- pkey_assert(*pkru_ptr);
-
- si_pkey_ptr = (u32 *)(((u8 *)si) + si_pkey_offset);
- dprintf1("si_pkey_ptr: %p\n", si_pkey_ptr);
- dump_mem(si_pkey_ptr - 8, 24);
- si_pkey = *si_pkey_ptr;
- pkey_assert(si_pkey < NR_PKEYS);
- last_si_pkey = si_pkey;
-
- if ((si->si_code == SEGV_MAPERR) ||
- (si->si_code == SEGV_ACCERR) ||
- (si->si_code == SEGV_BNDERR)) {
- printf("non-PK si_code, exiting...\n");
- exit(4);
- }
-
- dprintf1("signal pkru from xsave: %08x\n", *pkru_ptr);
- /* need __rdpkru() version so we do not do shadow_pkru checking */
- dprintf1("signal pkru from pkru: %08x\n", __rdpkru());
- dprintf1("si_pkey from siginfo: %jx\n", si_pkey);
- *(u64 *)pkru_ptr = 0x00000000;
- dprintf1("WARNING: set PRKU=0 to allow faulting instruction to continue\n");
- pkru_faults++;
- dprintf1("<<<<==================================================\n");
- return;
- if (trapno == 14) {
- fprintf(stderr,
- "ERROR: In signal handler, page fault, trapno = %d, ip = %016lx\n",
- trapno, ip);
- fprintf(stderr, "si_addr %p\n", si->si_addr);
- fprintf(stderr, "REG_ERR: %lx\n",
- (unsigned long)uctxt->uc_mcontext.gregs[REG_ERR]);
- exit(1);
- } else {
- fprintf(stderr, "unexpected trap %d! at 0x%lx\n", trapno, ip);
- fprintf(stderr, "si_addr %p\n", si->si_addr);
- fprintf(stderr, "REG_ERR: %lx\n",
- (unsigned long)uctxt->uc_mcontext.gregs[REG_ERR]);
- exit(2);
- }
- dprint_in_signal = 0;
-}
-
-int wait_all_children(void)
-{
- int status;
- return waitpid(-1, &status, 0);
-}
-
-void sig_chld(int x)
-{
- dprint_in_signal = 1;
- dprintf2("[%d] SIGCHLD: %d\n", getpid(), x);
- dprint_in_signal = 0;
-}
-
-void setup_sigsegv_handler(void)
-{
- int r, rs;
- struct sigaction newact;
- struct sigaction oldact;
-
- /* #PF is mapped to sigsegv */
- int signum = SIGSEGV;
-
- newact.sa_handler = 0;
- newact.sa_sigaction = signal_handler;
-
- /*sigset_t - signals to block while in the handler */
- /* get the old signal mask. */
- rs = sigprocmask(SIG_SETMASK, 0, &newact.sa_mask);
- pkey_assert(rs == 0);
-
- /* call sa_sigaction, not sa_handler*/
- newact.sa_flags = SA_SIGINFO;
-
- newact.sa_restorer = 0; /* void(*)(), obsolete */
- r = sigaction(signum, &newact, &oldact);
- r = sigaction(SIGALRM, &newact, &oldact);
- pkey_assert(r == 0);
-}
-
-void setup_handlers(void)
-{
- signal(SIGCHLD, &sig_chld);
- setup_sigsegv_handler();
-}
-
-pid_t fork_lazy_child(void)
-{
- pid_t forkret;
-
- forkret = fork();
- pkey_assert(forkret >= 0);
- dprintf3("[%d] fork() ret: %d\n", getpid(), forkret);
-
- if (!forkret) {
- /* in the child */
- while (1) {
- dprintf1("child sleeping...\n");
- sleep(30);
- }
- }
- return forkret;
-}
-
-void davecmp(void *_a, void *_b, int len)
-{
- int i;
- unsigned long *a = _a;
- unsigned long *b = _b;
-
- for (i = 0; i < len / sizeof(*a); i++) {
- if (a[i] == b[i])
- continue;
-
- dprintf3("[%3d]: a: %016lx b: %016lx\n", i, a[i], b[i]);
- }
-}
-
-void dumpit(char *f)
-{
- int fd = open(f, O_RDONLY);
- char buf[100];
- int nr_read;
-
- dprintf2("maps fd: %d\n", fd);
- do {
- nr_read = read(fd, &buf[0], sizeof(buf));
- write(1, buf, nr_read);
- } while (nr_read > 0);
- close(fd);
-}
-
-#define PKEY_DISABLE_ACCESS 0x1
-#define PKEY_DISABLE_WRITE 0x2
-
-u32 pkey_get(int pkey, unsigned long flags)
-{
- u32 mask = (PKEY_DISABLE_ACCESS|PKEY_DISABLE_WRITE);
- u32 pkru = __rdpkru();
- u32 shifted_pkru;
- u32 masked_pkru;
-
- dprintf1("%s(pkey=%d, flags=%lx) = %x / %d\n",
- __func__, pkey, flags, 0, 0);
- dprintf2("%s() raw pkru: %x\n", __func__, pkru);
-
- shifted_pkru = (pkru >> (pkey * PKRU_BITS_PER_PKEY));
- dprintf2("%s() shifted_pkru: %x\n", __func__, shifted_pkru);
- masked_pkru = shifted_pkru & mask;
- dprintf2("%s() masked pkru: %x\n", __func__, masked_pkru);
- /*
- * shift down the relevant bits to the lowest two, then
- * mask off all the other high bits.
- */
- return masked_pkru;
-}
-
-int pkey_set(int pkey, unsigned long rights, unsigned long flags)
-{
- u32 mask = (PKEY_DISABLE_ACCESS|PKEY_DISABLE_WRITE);
- u32 old_pkru = __rdpkru();
- u32 new_pkru;
-
- /* make sure that 'rights' only contains the bits we expect: */
- assert(!(rights & ~mask));
-
- /* copy old pkru */
- new_pkru = old_pkru;
- /* mask out bits from pkey in old value: */
- new_pkru &= ~(mask << (pkey * PKRU_BITS_PER_PKEY));
- /* OR in new bits for pkey: */
- new_pkru |= (rights << (pkey * PKRU_BITS_PER_PKEY));
-
- __wrpkru(new_pkru);
-
- dprintf3("%s(pkey=%d, rights=%lx, flags=%lx) = %x pkru now: %x old_pkru: %x\n",
- __func__, pkey, rights, flags, 0, __rdpkru(), old_pkru);
- return 0;
-}
-
-void pkey_disable_set(int pkey, int flags)
-{
- unsigned long syscall_flags = 0;
- int ret;
- int pkey_rights;
- u32 orig_pkru = rdpkru();
-
- dprintf1("START->%s(%d, 0x%x)\n", __func__,
- pkey, flags);
- pkey_assert(flags & (PKEY_DISABLE_ACCESS | PKEY_DISABLE_WRITE));
-
- pkey_rights = pkey_get(pkey, syscall_flags);
-
- dprintf1("%s(%d) pkey_get(%d): %x\n", __func__,
- pkey, pkey, pkey_rights);
- pkey_assert(pkey_rights >= 0);
-
- pkey_rights |= flags;
-
- ret = pkey_set(pkey, pkey_rights, syscall_flags);
- assert(!ret);
- /*pkru and flags have the same format */
- shadow_pkru |= flags << (pkey * 2);
- dprintf1("%s(%d) shadow: 0x%x\n", __func__, pkey, shadow_pkru);
-
- pkey_assert(ret >= 0);
-
- pkey_rights = pkey_get(pkey, syscall_flags);
- dprintf1("%s(%d) pkey_get(%d): %x\n", __func__,
- pkey, pkey, pkey_rights);
-
- dprintf1("%s(%d) pkru: 0x%x\n", __func__, pkey, rdpkru());
- if (flags)
- pkey_assert(rdpkru() > orig_pkru);
- dprintf1("END<---%s(%d, 0x%x)\n", __func__,
- pkey, flags);
-}
-
-void pkey_disable_clear(int pkey, int flags)
-{
- unsigned long syscall_flags = 0;
- int ret;
- int pkey_rights = pkey_get(pkey, syscall_flags);
- u32 orig_pkru = rdpkru();
-
- pkey_assert(flags & (PKEY_DISABLE_ACCESS | PKEY_DISABLE_WRITE));
-
- dprintf1("%s(%d) pkey_get(%d): %x\n", __func__,
- pkey, pkey, pkey_rights);
- pkey_assert(pkey_rights >= 0);
-
- pkey_rights |= flags;
-
- ret = pkey_set(pkey, pkey_rights, 0);
- /* pkru and flags have the same format */
- shadow_pkru &= ~(flags << (pkey * 2));
- pkey_assert(ret >= 0);
-
- pkey_rights = pkey_get(pkey, syscall_flags);
- dprintf1("%s(%d) pkey_get(%d): %x\n", __func__,
- pkey, pkey, pkey_rights);
-
- dprintf1("%s(%d) pkru: 0x%x\n", __func__, pkey, rdpkru());
- if (flags)
- assert(rdpkru() > orig_pkru);
-}
-
-void pkey_write_allow(int pkey)
-{
- pkey_disable_clear(pkey, PKEY_DISABLE_WRITE);
-}
-void pkey_write_deny(int pkey)
-{
- pkey_disable_set(pkey, PKEY_DISABLE_WRITE);
-}
-void pkey_access_allow(int pkey)
-{
- pkey_disable_clear(pkey, PKEY_DISABLE_ACCESS);
-}
-void pkey_access_deny(int pkey)
-{
- pkey_disable_set(pkey, PKEY_DISABLE_ACCESS);
-}
-
-int sys_mprotect_pkey(void *ptr, size_t size, unsigned long orig_prot,
- unsigned long pkey)
-{
- int sret;
-
- dprintf2("%s(0x%p, %zx, prot=%lx, pkey=%lx)\n", __func__,
- ptr, size, orig_prot, pkey);
-
- errno = 0;
- sret = syscall(SYS_mprotect_key, ptr, size, orig_prot, pkey);
- if (errno) {
- dprintf2("SYS_mprotect_key sret: %d\n", sret);
- dprintf2("SYS_mprotect_key prot: 0x%lx\n", orig_prot);
- dprintf2("SYS_mprotect_key failed, errno: %d\n", errno);
- if (DEBUG_LEVEL >= 2)
- perror("SYS_mprotect_pkey");
- }
- return sret;
-}
-
-int sys_pkey_alloc(unsigned long flags, unsigned long init_val)
-{
- int ret = syscall(SYS_pkey_alloc, flags, init_val);
- dprintf1("%s(flags=%lx, init_val=%lx) syscall ret: %d errno: %d\n",
- __func__, flags, init_val, ret, errno);
- return ret;
-}
-
-int alloc_pkey(void)
-{
- int ret;
- unsigned long init_val = 0x0;
-
- dprintf1("alloc_pkey()::%d, pkru: 0x%x shadow: %x\n",
- __LINE__, __rdpkru(), shadow_pkru);
- ret = sys_pkey_alloc(0, init_val);
- /*
- * pkey_alloc() sets PKRU, so we need to reflect it in
- * shadow_pkru:
- */
- dprintf4("alloc_pkey()::%d, ret: %d pkru: 0x%x shadow: 0x%x\n",
- __LINE__, ret, __rdpkru(), shadow_pkru);
- if (ret) {
- /* clear both the bits: */
- shadow_pkru &= ~(0x3 << (ret * 2));
- dprintf4("alloc_pkey()::%d, ret: %d pkru: 0x%x shadow: 0x%x\n",
- __LINE__, ret, __rdpkru(), shadow_pkru);
- /*
- * move the new state in from init_val
- * (remember, we cheated and init_val == pkru format)
- */
- shadow_pkru |= (init_val << (ret * 2));
- }
- dprintf4("alloc_pkey()::%d, ret: %d pkru: 0x%x shadow: 0x%x\n",
- __LINE__, ret, __rdpkru(), shadow_pkru);
- dprintf1("alloc_pkey()::%d errno: %d\n", __LINE__, errno);
- /* for shadow checking: */
- rdpkru();
- dprintf4("alloc_pkey()::%d, ret: %d pkru: 0x%x shadow: 0x%x\n",
- __LINE__, ret, __rdpkru(), shadow_pkru);
- return ret;
-}
-
-int sys_pkey_free(unsigned long pkey)
-{
- int ret = syscall(SYS_pkey_free, pkey);
- dprintf1("%s(pkey=%ld) syscall ret: %d\n", __func__, pkey, ret);
- return ret;
-}
-
-/*
- * I had a bug where pkey bits could be set by mprotect() but
- * not cleared. This ensures we get lots of random bit sets
- * and clears on the vma and pte pkey bits.
- */
-int alloc_random_pkey(void)
-{
- int max_nr_pkey_allocs;
- int ret;
- int i;
- int alloced_pkeys[NR_PKEYS];
- int nr_alloced = 0;
- int random_index;
- memset(alloced_pkeys, 0, sizeof(alloced_pkeys));
-
- /* allocate every possible key and make a note of which ones we got */
- max_nr_pkey_allocs = NR_PKEYS;
- max_nr_pkey_allocs = 1;
- for (i = 0; i < max_nr_pkey_allocs; i++) {
- int new_pkey = alloc_pkey();
- if (new_pkey < 0)
- break;
- alloced_pkeys[nr_alloced++] = new_pkey;
- }
-
- pkey_assert(nr_alloced > 0);
- /* select a random one out of the allocated ones */
- random_index = rand() % nr_alloced;
- ret = alloced_pkeys[random_index];
- /* now zero it out so we don't free it next */
- alloced_pkeys[random_index] = 0;
-
- /* go through the allocated ones that we did not want and free them */
- for (i = 0; i < nr_alloced; i++) {
- int free_ret;
- if (!alloced_pkeys[i])
- continue;
- free_ret = sys_pkey_free(alloced_pkeys[i]);
- pkey_assert(!free_ret);
- }
- dprintf1("%s()::%d, ret: %d pkru: 0x%x shadow: 0x%x\n", __func__,
- __LINE__, ret, __rdpkru(), shadow_pkru);
- return ret;
-}
-
-int mprotect_pkey(void *ptr, size_t size, unsigned long orig_prot,
- unsigned long pkey)
-{
- int nr_iterations = random() % 100;
- int ret;
-
- while (0) {
- int rpkey = alloc_random_pkey();
- ret = sys_mprotect_pkey(ptr, size, orig_prot, pkey);
- dprintf1("sys_mprotect_pkey(%p, %zx, prot=0x%lx, pkey=%ld) ret: %d\n",
- ptr, size, orig_prot, pkey, ret);
- if (nr_iterations-- < 0)
- break;
-
- dprintf1("%s()::%d, ret: %d pkru: 0x%x shadow: 0x%x\n", __func__,
- __LINE__, ret, __rdpkru(), shadow_pkru);
- sys_pkey_free(rpkey);
- dprintf1("%s()::%d, ret: %d pkru: 0x%x shadow: 0x%x\n", __func__,
- __LINE__, ret, __rdpkru(), shadow_pkru);
- }
- pkey_assert(pkey < NR_PKEYS);
-
- ret = sys_mprotect_pkey(ptr, size, orig_prot, pkey);
- dprintf1("mprotect_pkey(%p, %zx, prot=0x%lx, pkey=%ld) ret: %d\n",
- ptr, size, orig_prot, pkey, ret);
- pkey_assert(!ret);
- dprintf1("%s()::%d, ret: %d pkru: 0x%x shadow: 0x%x\n", __func__,
- __LINE__, ret, __rdpkru(), shadow_pkru);
- return ret;
-}
-
-struct pkey_malloc_record {
- void *ptr;
- long size;
-};
-struct pkey_malloc_record *pkey_malloc_records;
-long nr_pkey_malloc_records;
-void record_pkey_malloc(void *ptr, long size)
-{
- long i;
- struct pkey_malloc_record *rec = NULL;
-
- for (i = 0; i < nr_pkey_malloc_records; i++) {
- rec = &pkey_malloc_records[i];
- /* find a free record */
- if (rec)
- break;
- }
- if (!rec) {
- /* every record is full */
- size_t old_nr_records = nr_pkey_malloc_records;
- size_t new_nr_records = (nr_pkey_malloc_records * 2 + 1);
- size_t new_size = new_nr_records * sizeof(struct pkey_malloc_record);
- dprintf2("new_nr_records: %zd\n", new_nr_records);
- dprintf2("new_size: %zd\n", new_size);
- pkey_malloc_records = realloc(pkey_malloc_records, new_size);
- pkey_assert(pkey_malloc_records != NULL);
- rec = &pkey_malloc_records[nr_pkey_malloc_records];
- /*
- * realloc() does not initialize memory, so zero it from
- * the first new record all the way to the end.
- */
- for (i = 0; i < new_nr_records - old_nr_records; i++)
- memset(rec + i, 0, sizeof(*rec));
- }
- dprintf3("filling malloc record[%d/%p]: {%p, %ld}\n",
- (int)(rec - pkey_malloc_records), rec, ptr, size);
- rec->ptr = ptr;
- rec->size = size;
- nr_pkey_malloc_records++;
-}
-
-void free_pkey_malloc(void *ptr)
-{
- long i;
- int ret;
- dprintf3("%s(%p)\n", __func__, ptr);
- for (i = 0; i < nr_pkey_malloc_records; i++) {
- struct pkey_malloc_record *rec = &pkey_malloc_records[i];
- dprintf4("looking for ptr %p at record[%ld/%p]: {%p, %ld}\n",
- ptr, i, rec, rec->ptr, rec->size);
- if ((ptr < rec->ptr) ||
- (ptr >= rec->ptr + rec->size))
- continue;
-
- dprintf3("found ptr %p at record[%ld/%p]: {%p, %ld}\n",
- ptr, i, rec, rec->ptr, rec->size);
- nr_pkey_malloc_records--;
- ret = munmap(rec->ptr, rec->size);
- dprintf3("munmap ret: %d\n", ret);
- pkey_assert(!ret);
- dprintf3("clearing rec->ptr, rec: %p\n", rec);
- rec->ptr = NULL;
- dprintf3("done clearing rec->ptr, rec: %p\n", rec);
- return;
- }
- pkey_assert(false);
-}
-
-
-void *malloc_pkey_with_mprotect(long size, int prot, u16 pkey)
-{
- void *ptr;
- int ret;
-
- rdpkru();
- dprintf1("doing %s(size=%ld, prot=0x%x, pkey=%d)\n", __func__,
- size, prot, pkey);
- pkey_assert(pkey < NR_PKEYS);
- ptr = mmap(NULL, size, prot, MAP_ANONYMOUS|MAP_PRIVATE, -1, 0);
- pkey_assert(ptr != (void *)-1);
- ret = mprotect_pkey((void *)ptr, PAGE_SIZE, prot, pkey);
- pkey_assert(!ret);
- record_pkey_malloc(ptr, size);
- rdpkru();
-
- dprintf1("%s() for pkey %d @ %p\n", __func__, pkey, ptr);
- return ptr;
-}
-
-void *malloc_pkey_anon_huge(long size, int prot, u16 pkey)
-{
- int ret;
- void *ptr;
-
- dprintf1("doing %s(size=%ld, prot=0x%x, pkey=%d)\n", __func__,
- size, prot, pkey);
- /*
- * Guarantee we can fit at least one huge page in the resulting
- * allocation by allocating space for 2:
- */
- size = ALIGN_UP(size, HPAGE_SIZE * 2);
- ptr = mmap(NULL, size, PROT_NONE, MAP_ANONYMOUS|MAP_PRIVATE, -1, 0);
- pkey_assert(ptr != (void *)-1);
- record_pkey_malloc(ptr, size);
- mprotect_pkey(ptr, size, prot, pkey);
-
- dprintf1("unaligned ptr: %p\n", ptr);
- ptr = ALIGN_PTR_UP(ptr, HPAGE_SIZE);
- dprintf1(" aligned ptr: %p\n", ptr);
- ret = madvise(ptr, HPAGE_SIZE, MADV_HUGEPAGE);
- dprintf1("MADV_HUGEPAGE ret: %d\n", ret);
- ret = madvise(ptr, HPAGE_SIZE, MADV_WILLNEED);
- dprintf1("MADV_WILLNEED ret: %d\n", ret);
- memset(ptr, 0, HPAGE_SIZE);
-
- dprintf1("mmap()'d thp for pkey %d @ %p\n", pkey, ptr);
- return ptr;
-}
-
-int hugetlb_setup_ok;
-#define GET_NR_HUGE_PAGES 10
-void setup_hugetlbfs(void)
-{
- int err;
- int fd;
- char buf[] = "123";
-
- if (geteuid() != 0) {
- fprintf(stderr, "WARNING: not run as root, can not do hugetlb test\n");
- return;
- }
-
- cat_into_file(__stringify(GET_NR_HUGE_PAGES), "/proc/sys/vm/nr_hugepages");
-
- /*
- * Now go make sure that we got the pages and that they
- * are 2M pages. Someone might have made 1G the default.
- */
- fd = open("/sys/kernel/mm/hugepages/hugepages-2048kB/nr_hugepages", O_RDONLY);
- if (fd < 0) {
- perror("opening sysfs 2M hugetlb config");
- return;
- }
-
- /* -1 to guarantee leaving the trailing \0 */
- err = read(fd, buf, sizeof(buf)-1);
- close(fd);
- if (err <= 0) {
- perror("reading sysfs 2M hugetlb config");
- return;
- }
-
- if (atoi(buf) != GET_NR_HUGE_PAGES) {
- fprintf(stderr, "could not confirm 2M pages, got: '%s' expected %d\n",
- buf, GET_NR_HUGE_PAGES);
- return;
- }
-
- hugetlb_setup_ok = 1;
-}
-
-void *malloc_pkey_hugetlb(long size, int prot, u16 pkey)
-{
- void *ptr;
- int flags = MAP_ANONYMOUS|MAP_PRIVATE|MAP_HUGETLB;
-
- if (!hugetlb_setup_ok)
- return PTR_ERR_ENOTSUP;
-
- dprintf1("doing %s(%ld, %x, %x)\n", __func__, size, prot, pkey);
- size = ALIGN_UP(size, HPAGE_SIZE * 2);
- pkey_assert(pkey < NR_PKEYS);
- ptr = mmap(NULL, size, PROT_NONE, flags, -1, 0);
- pkey_assert(ptr != (void *)-1);
- mprotect_pkey(ptr, size, prot, pkey);
-
- record_pkey_malloc(ptr, size);
-
- dprintf1("mmap()'d hugetlbfs for pkey %d @ %p\n", pkey, ptr);
- return ptr;
-}
-
-void *malloc_pkey_mmap_dax(long size, int prot, u16 pkey)
-{
- void *ptr;
- int fd;
-
- dprintf1("doing %s(size=%ld, prot=0x%x, pkey=%d)\n", __func__,
- size, prot, pkey);
- pkey_assert(pkey < NR_PKEYS);
- fd = open("/dax/foo", O_RDWR);
- pkey_assert(fd >= 0);
-
- ptr = mmap(0, size, prot, MAP_SHARED, fd, 0);
- pkey_assert(ptr != (void *)-1);
-
- mprotect_pkey(ptr, size, prot, pkey);
-
- record_pkey_malloc(ptr, size);
-
- dprintf1("mmap()'d for pkey %d @ %p\n", pkey, ptr);
- close(fd);
- return ptr;
-}
-
-void *(*pkey_malloc[])(long size, int prot, u16 pkey) = {
-
- malloc_pkey_with_mprotect,
- malloc_pkey_anon_huge,
- malloc_pkey_hugetlb
-/* can not do direct with the pkey_mprotect() API:
- malloc_pkey_mmap_direct,
- malloc_pkey_mmap_dax,
-*/
-};
-
-void *malloc_pkey(long size, int prot, u16 pkey)
-{
- void *ret;
- static int malloc_type;
- int nr_malloc_types = ARRAY_SIZE(pkey_malloc);
-
- pkey_assert(pkey < NR_PKEYS);
-
- while (1) {
- pkey_assert(malloc_type < nr_malloc_types);
-
- ret = pkey_malloc[malloc_type](size, prot, pkey);
- pkey_assert(ret != (void *)-1);
-
- malloc_type++;
- if (malloc_type >= nr_malloc_types)
- malloc_type = (random()%nr_malloc_types);
-
- /* try again if the malloc_type we tried is unsupported */
- if (ret == PTR_ERR_ENOTSUP)
- continue;
-
- break;
- }
-
- dprintf3("%s(%ld, prot=%x, pkey=%x) returning: %p\n", __func__,
- size, prot, pkey, ret);
- return ret;
-}
-
-int last_pkru_faults;
-void expected_pk_fault(int pkey)
-{
- dprintf2("%s(): last_pkru_faults: %d pkru_faults: %d\n",
- __func__, last_pkru_faults, pkru_faults);
- dprintf2("%s(%d): last_si_pkey: %d\n", __func__, pkey, last_si_pkey);
- pkey_assert(last_pkru_faults + 1 == pkru_faults);
- pkey_assert(last_si_pkey == pkey);
- /*
- * The signal handler shold have cleared out PKRU to let the
- * test program continue. We now have to restore it.
- */
- if (__rdpkru() != 0)
- pkey_assert(0);
-
- __wrpkru(shadow_pkru);
- dprintf1("%s() set PKRU=%x to restore state after signal nuked it\n",
- __func__, shadow_pkru);
- last_pkru_faults = pkru_faults;
- last_si_pkey = -1;
-}
-
-void do_not_expect_pk_fault(void)
-{
- pkey_assert(last_pkru_faults == pkru_faults);
-}
-
-int test_fds[10] = { -1 };
-int nr_test_fds;
-void __save_test_fd(int fd)
-{
- pkey_assert(fd >= 0);
- pkey_assert(nr_test_fds < ARRAY_SIZE(test_fds));
- test_fds[nr_test_fds] = fd;
- nr_test_fds++;
-}
-
-int get_test_read_fd(void)
-{
- int test_fd = open("/etc/passwd", O_RDONLY);
- __save_test_fd(test_fd);
- return test_fd;
-}
-
-void close_test_fds(void)
-{
- int i;
-
- for (i = 0; i < nr_test_fds; i++) {
- if (test_fds[i] < 0)
- continue;
- close(test_fds[i]);
- test_fds[i] = -1;
- }
- nr_test_fds = 0;
-}
-
-#define barrier() __asm__ __volatile__("": : :"memory")
-__attribute__((noinline)) int read_ptr(int *ptr)
-{
- /*
- * Keep GCC from optimizing this away somehow
- */
- barrier();
- return *ptr;
-}
-
-void test_read_of_write_disabled_region(int *ptr, u16 pkey)
-{
- int ptr_contents;
-
- dprintf1("disabling write access to PKEY[1], doing read\n");
- pkey_write_deny(pkey);
- ptr_contents = read_ptr(ptr);
- dprintf1("*ptr: %d\n", ptr_contents);
- dprintf1("\n");
-}
-void test_read_of_access_disabled_region(int *ptr, u16 pkey)
-{
- int ptr_contents;
-
- dprintf1("disabling access to PKEY[%02d], doing read @ %p\n", pkey, ptr);
- rdpkru();
- pkey_access_deny(pkey);
- ptr_contents = read_ptr(ptr);
- dprintf1("*ptr: %d\n", ptr_contents);
- expected_pk_fault(pkey);
-}
-void test_write_of_write_disabled_region(int *ptr, u16 pkey)
-{
- dprintf1("disabling write access to PKEY[%02d], doing write\n", pkey);
- pkey_write_deny(pkey);
- *ptr = __LINE__;
- expected_pk_fault(pkey);
-}
-void test_write_of_access_disabled_region(int *ptr, u16 pkey)
-{
- dprintf1("disabling access to PKEY[%02d], doing write\n", pkey);
- pkey_access_deny(pkey);
- *ptr = __LINE__;
- expected_pk_fault(pkey);
-}
-void test_kernel_write_of_access_disabled_region(int *ptr, u16 pkey)
-{
- int ret;
- int test_fd = get_test_read_fd();
-
- dprintf1("disabling access to PKEY[%02d], "
- "having kernel read() to buffer\n", pkey);
- pkey_access_deny(pkey);
- ret = read(test_fd, ptr, 1);
- dprintf1("read ret: %d\n", ret);
- pkey_assert(ret);
-}
-void test_kernel_write_of_write_disabled_region(int *ptr, u16 pkey)
-{
- int ret;
- int test_fd = get_test_read_fd();
-
- pkey_write_deny(pkey);
- ret = read(test_fd, ptr, 100);
- dprintf1("read ret: %d\n", ret);
- if (ret < 0 && (DEBUG_LEVEL > 0))
- perror("verbose read result (OK for this to be bad)");
- pkey_assert(ret);
-}
-
-void test_kernel_gup_of_access_disabled_region(int *ptr, u16 pkey)
-{
- int pipe_ret, vmsplice_ret;
- struct iovec iov;
- int pipe_fds[2];
-
- pipe_ret = pipe(pipe_fds);
-
- pkey_assert(pipe_ret == 0);
- dprintf1("disabling access to PKEY[%02d], "
- "having kernel vmsplice from buffer\n", pkey);
- pkey_access_deny(pkey);
- iov.iov_base = ptr;
- iov.iov_len = PAGE_SIZE;
- vmsplice_ret = vmsplice(pipe_fds[1], &iov, 1, SPLICE_F_GIFT);
- dprintf1("vmsplice() ret: %d\n", vmsplice_ret);
- pkey_assert(vmsplice_ret == -1);
-
- close(pipe_fds[0]);
- close(pipe_fds[1]);
-}
-
-void test_kernel_gup_write_to_write_disabled_region(int *ptr, u16 pkey)
-{
- int ignored = 0xdada;
- int futex_ret;
- int some_int = __LINE__;
-
- dprintf1("disabling write to PKEY[%02d], "
- "doing futex gunk in buffer\n", pkey);
- *ptr = some_int;
- pkey_write_deny(pkey);
- futex_ret = syscall(SYS_futex, ptr, FUTEX_WAIT, some_int-1, NULL,
- &ignored, ignored);
- if (DEBUG_LEVEL > 0)
- perror("futex");
- dprintf1("futex() ret: %d\n", futex_ret);
-}
-
-/* Assumes that all pkeys other than 'pkey' are unallocated */
-void test_pkey_syscalls_on_non_allocated_pkey(int *ptr, u16 pkey)
-{
- int err;
- int i;
-
- /* Note: 0 is the default pkey, so don't mess with it */
- for (i = 1; i < NR_PKEYS; i++) {
- if (pkey == i)
- continue;
-
- dprintf1("trying get/set/free to non-allocated pkey: %2d\n", i);
- err = sys_pkey_free(i);
- pkey_assert(err);
-
- err = sys_pkey_free(i);
- pkey_assert(err);
-
- err = sys_mprotect_pkey(ptr, PAGE_SIZE, PROT_READ, i);
- pkey_assert(err);
- }
-}
-
-/* Assumes that all pkeys other than 'pkey' are unallocated */
-void test_pkey_syscalls_bad_args(int *ptr, u16 pkey)
-{
- int err;
- int bad_pkey = NR_PKEYS+99;
-
- /* pass a known-invalid pkey in: */
- err = sys_mprotect_pkey(ptr, PAGE_SIZE, PROT_READ, bad_pkey);
- pkey_assert(err);
-}
-
-/* Assumes that all pkeys other than 'pkey' are unallocated */
-void test_pkey_alloc_exhaust(int *ptr, u16 pkey)
-{
- int err;
- int allocated_pkeys[NR_PKEYS] = {0};
- int nr_allocated_pkeys = 0;
- int i;
-
- for (i = 0; i < NR_PKEYS*2; i++) {
- int new_pkey;
- dprintf1("%s() alloc loop: %d\n", __func__, i);
- new_pkey = alloc_pkey();
- dprintf4("%s()::%d, err: %d pkru: 0x%x shadow: 0x%x\n", __func__,
- __LINE__, err, __rdpkru(), shadow_pkru);
- rdpkru(); /* for shadow checking */
- dprintf2("%s() errno: %d ENOSPC: %d\n", __func__, errno, ENOSPC);
- if ((new_pkey == -1) && (errno == ENOSPC)) {
- dprintf2("%s() failed to allocate pkey after %d tries\n",
- __func__, nr_allocated_pkeys);
- break;
- }
- pkey_assert(nr_allocated_pkeys < NR_PKEYS);
- allocated_pkeys[nr_allocated_pkeys++] = new_pkey;
- }
-
- dprintf3("%s()::%d\n", __func__, __LINE__);
-
- /*
- * ensure it did not reach the end of the loop without
- * failure:
- */
- pkey_assert(i < NR_PKEYS*2);
-
- /*
- * There are 16 pkeys supported in hardware. One is taken
- * up for the default (0) and another can be taken up by
- * an execute-only mapping. Ensure that we can allocate
- * at least 14 (16-2).
- */
- pkey_assert(i >= NR_PKEYS-2);
-
- for (i = 0; i < nr_allocated_pkeys; i++) {
- err = sys_pkey_free(allocated_pkeys[i]);
- pkey_assert(!err);
- rdpkru(); /* for shadow checking */
- }
-}
-
-void test_ptrace_of_child(int *ptr, u16 pkey)
-{
- __attribute__((__unused__)) int peek_result;
- pid_t child_pid;
- void *ignored = 0;
- long ret;
- int status;
- /*
- * This is the "control" for our little expermient. Make sure
- * we can always access it when ptracing.
- */
- int *plain_ptr_unaligned = malloc(HPAGE_SIZE);
- int *plain_ptr = ALIGN_PTR_UP(plain_ptr_unaligned, PAGE_SIZE);
-
- /*
- * Fork a child which is an exact copy of this process, of course.
- * That means we can do all of our tests via ptrace() and then plain
- * memory access and ensure they work differently.
- */
- child_pid = fork_lazy_child();
- dprintf1("[%d] child pid: %d\n", getpid(), child_pid);
-
- ret = ptrace(PTRACE_ATTACH, child_pid, ignored, ignored);
- if (ret)
- perror("attach");
- dprintf1("[%d] attach ret: %ld %d\n", getpid(), ret, __LINE__);
- pkey_assert(ret != -1);
- ret = waitpid(child_pid, &status, WUNTRACED);
- if ((ret != child_pid) || !(WIFSTOPPED(status))) {
- fprintf(stderr, "weird waitpid result %ld stat %x\n",
- ret, status);
- pkey_assert(0);
- }
- dprintf2("waitpid ret: %ld\n", ret);
- dprintf2("waitpid status: %d\n", status);
-
- pkey_access_deny(pkey);
- pkey_write_deny(pkey);
-
- /* Write access, untested for now:
- ret = ptrace(PTRACE_POKEDATA, child_pid, peek_at, data);
- pkey_assert(ret != -1);
- dprintf1("poke at %p: %ld\n", peek_at, ret);
- */
-
- /*
- * Try to access the pkey-protected "ptr" via ptrace:
- */
- ret = ptrace(PTRACE_PEEKDATA, child_pid, ptr, ignored);
- /* expect it to work, without an error: */
- pkey_assert(ret != -1);
- /* Now access from the current task, and expect an exception: */
- peek_result = read_ptr(ptr);
- expected_pk_fault(pkey);
-
- /*
- * Try to access the NON-pkey-protected "plain_ptr" via ptrace:
- */
- ret = ptrace(PTRACE_PEEKDATA, child_pid, plain_ptr, ignored);
- /* expect it to work, without an error: */
- pkey_assert(ret != -1);
- /* Now access from the current task, and expect NO exception: */
- peek_result = read_ptr(plain_ptr);
- do_not_expect_pk_fault();
-
- ret = ptrace(PTRACE_DETACH, child_pid, ignored, 0);
- pkey_assert(ret != -1);
-
- ret = kill(child_pid, SIGKILL);
- pkey_assert(ret != -1);
-
- wait(&status);
-
- free(plain_ptr_unaligned);
-}
-
-void test_executing_on_unreadable_memory(int *ptr, u16 pkey)
-{
- void *p1;
- int scratch;
- int ptr_contents;
- int ret;
-
- p1 = ALIGN_PTR_UP(&lots_o_noops_around_write, PAGE_SIZE);
- dprintf3("&lots_o_noops: %p\n", &lots_o_noops_around_write);
- /* lots_o_noops_around_write should be page-aligned already */
- assert(p1 == &lots_o_noops_around_write);
-
- /* Point 'p1' at the *second* page of the function: */
- p1 += PAGE_SIZE;
-
- madvise(p1, PAGE_SIZE, MADV_DONTNEED);
- lots_o_noops_around_write(&scratch);
- ptr_contents = read_ptr(p1);
- dprintf2("ptr (%p) contents@%d: %x\n", p1, __LINE__, ptr_contents);
-
- ret = mprotect_pkey(p1, PAGE_SIZE, PROT_EXEC, (u64)pkey);
- pkey_assert(!ret);
- pkey_access_deny(pkey);
-
- dprintf2("pkru: %x\n", rdpkru());
-
- /*
- * Make sure this is an *instruction* fault
- */
- madvise(p1, PAGE_SIZE, MADV_DONTNEED);
- lots_o_noops_around_write(&scratch);
- do_not_expect_pk_fault();
- ptr_contents = read_ptr(p1);
- dprintf2("ptr (%p) contents@%d: %x\n", p1, __LINE__, ptr_contents);
- expected_pk_fault(pkey);
-}
-
-void test_mprotect_pkey_on_unsupported_cpu(int *ptr, u16 pkey)
-{
- int size = PAGE_SIZE;
- int sret;
-
- if (cpu_has_pku()) {
- dprintf1("SKIP: %s: no CPU support\n", __func__);
- return;
- }
-
- sret = syscall(SYS_mprotect_key, ptr, size, PROT_READ, pkey);
- pkey_assert(sret < 0);
-}
-
-void (*pkey_tests[])(int *ptr, u16 pkey) = {
- test_read_of_write_disabled_region,
- test_read_of_access_disabled_region,
- test_write_of_write_disabled_region,
- test_write_of_access_disabled_region,
- test_kernel_write_of_access_disabled_region,
- test_kernel_write_of_write_disabled_region,
- test_kernel_gup_of_access_disabled_region,
- test_kernel_gup_write_to_write_disabled_region,
- test_executing_on_unreadable_memory,
- test_ptrace_of_child,
- test_pkey_syscalls_on_non_allocated_pkey,
- test_pkey_syscalls_bad_args,
- test_pkey_alloc_exhaust,
-};
-
-void run_tests_once(void)
-{
- int *ptr;
- int prot = PROT_READ|PROT_WRITE;
-
- for (test_nr = 0; test_nr < ARRAY_SIZE(pkey_tests); test_nr++) {
- int pkey;
- int orig_pkru_faults = pkru_faults;
-
- dprintf1("======================\n");
- dprintf1("test %d preparing...\n", test_nr);
-
- tracing_on();
- pkey = alloc_random_pkey();
- dprintf1("test %d starting with pkey: %d\n", test_nr, pkey);
- ptr = malloc_pkey(PAGE_SIZE, prot, pkey);
- dprintf1("test %d starting...\n", test_nr);
- pkey_tests[test_nr](ptr, pkey);
- dprintf1("freeing test memory: %p\n", ptr);
- free_pkey_malloc(ptr);
- sys_pkey_free(pkey);
-
- dprintf1("pkru_faults: %d\n", pkru_faults);
- dprintf1("orig_pkru_faults: %d\n", orig_pkru_faults);
-
- tracing_off();
- close_test_fds();
-
- printf("test %2d PASSED (iteration %d)\n", test_nr, iteration_nr);
- dprintf1("======================\n\n");
- }
- iteration_nr++;
-}
-
-void pkey_setup_shadow(void)
-{
- shadow_pkru = __rdpkru();
-}
-
-int main(void)
-{
- int nr_iterations = 22;
-
- setup_handlers();
-
- printf("has pku: %d\n", cpu_has_pku());
-
- if (!cpu_has_pku()) {
- int size = PAGE_SIZE;
- int *ptr;
-
- printf("running PKEY tests for unsupported CPU/OS\n");
-
- ptr = mmap(NULL, size, PROT_NONE, MAP_ANONYMOUS|MAP_PRIVATE, -1, 0);
- assert(ptr != (void *)-1);
- test_mprotect_pkey_on_unsupported_cpu(ptr, 1);
- exit(0);
- }
-
- pkey_setup_shadow();
- printf("startup pkru: %x\n", rdpkru());
- setup_hugetlbfs();
-
- while (nr_iterations-- > 0)
- run_tests_once();
-
- printf("done (all tests OK)\n");
- return 0;
-}
--
1.8.3.1

2017-06-27 10:13:04

by Ram Pai

Subject: [RFC v4 16/17] Documentation: PowerPC specific updates to memory protection keys

Add documentation updates that capture PowerPC specific changes.

Signed-off-by: Ram Pai <[email protected]>
---
Documentation/vm/protection-keys.txt | 89 ++++++++++++++++++++++++++++--------
1 file changed, 69 insertions(+), 20 deletions(-)

diff --git a/Documentation/vm/protection-keys.txt b/Documentation/vm/protection-keys.txt
index b643045..889f32e 100644
--- a/Documentation/vm/protection-keys.txt
+++ b/Documentation/vm/protection-keys.txt
@@ -1,21 +1,46 @@
-Memory Protection Keys for Userspace (PKU aka PKEYs) is a CPU feature
-which will be found on future Intel CPUs.
+Memory Protection Keys for Userspace (PKU aka PKEYs) is a CPU feature found in
+new generation of intel CPUs and on PowerPC 7 and higher CPUs.

Memory Protection Keys provides a mechanism for enforcing page-based
-protections, but without requiring modification of the page tables
-when an application changes protection domains. It works by
-dedicating 4 previously ignored bits in each page table entry to a
-"protection key", giving 16 possible keys.
-
-There is also a new user-accessible register (PKRU) with two separate
-bits (Access Disable and Write Disable) for each key. Being a CPU
-register, PKRU is inherently thread-local, potentially giving each
-thread a different set of protections from every other thread.
-
-There are two new instructions (RDPKRU/WRPKRU) for reading and writing
-to the new register. The feature is only available in 64-bit mode,
-even though there is theoretically space in the PAE PTEs. These
-permissions are enforced on data access only and have no effect on
+protections, but without requiring modification of the page tables when an
+application changes protection domains.
+
+
+On Intel:
+
+ It works by dedicating 4 previously ignored bits in each page table
+ entry to a "protection key", giving 16 possible keys.
+
+ There is also a new user-accessible register (PKRU) with two separate
+ bits (Access Disable and Write Disable) for each key. Being a CPU
+ register, PKRU is inherently thread-local, potentially giving each
+ thread a different set of protections from every other thread.
+
+ There are two new instructions (RDPKRU/WRPKRU) for reading and writing
+ to the new register. The feature is only available in 64-bit mode,
+ even though there is theoretically space in the PAE PTEs. These
+ permissions are enforced on data access only and have no effect on
+ instruction fetches.
+
+
+On PowerPC:
+
+ It works by dedicating 5 hash-page table entry bits to a "protection key",
+ giving 32 possible keys.
+
+ There is a user-accessible register (AMR) with two separate bits;
+ Access Disable and Write Disable, for each key. Being a CPU
+ register, AMR is inherently thread-local, potentially giving each
+ thread a different set of protections from every other thread. NOTE:
+ Disabling read permission does not disable write and vice-versa.
+
+ The feature is available on 64-bit HPTE mode only.
+ 'mtspr 0xd, mem' reads the AMR register
+ 'mfspr mem, 0xd' writes into the AMR register.
+
+
+
+Permissions are enforced on data access only and have no effect on
instruction fetches.

=========================== Syscalls ===========================
@@ -28,9 +53,9 @@ There are 3 system calls which directly interact with pkeys:
unsigned long prot, int pkey);

Before a pkey can be used, it must first be allocated with
-pkey_alloc(). An application calls the WRPKRU instruction
+pkey_alloc(). An application calls the WRPKRU/AMR instruction
directly in order to change access permissions to memory covered
-with a key. In this example WRPKRU is wrapped by a C function
+with a key. In this example WRPKRU/AMR is wrapped by a C function
called pkey_set().

int real_prot = PROT_READ|PROT_WRITE;
@@ -52,11 +77,11 @@ is no longer in use:
munmap(ptr, PAGE_SIZE);
pkey_free(pkey);

-(Note: pkey_set() is a wrapper for the RDPKRU and WRPKRU instructions.
+(Note: pkey_set() is a wrapper for the RDPKRU,WRPKRU or AMR instructions.
An example implementation can be found in
tools/testing/selftests/x86/protection_keys.c)

-=========================== Behavior ===========================
+=========================== Behavior =================================

The kernel attempts to make protection keys consistent with the
behavior of a plain mprotect(). For instance if you do this:
@@ -83,3 +108,27 @@ with a read():
The kernel will send a SIGSEGV in both cases, but si_code will be set
to SEGV_PKERR when violating protection keys versus SEGV_ACCERR when
the plain mprotect() permissions are violated.
+
+
+====================================================================
+ Semantic differences
+
+The following semantic differences exist between x86 and power.
+
+a) powerpc allows creation of a key with execute-disabled. The following
+ is allowed on powerpc.
+ pkey = pkey_alloc(0, PKEY_DISABLE_WRITE | PKEY_DISABLE_READ |
+ PKEY_DISABLE_EXECUTE);
+ x86 disallows PKEY_DISABLE_EXECUTE during key creation.
+
+b) x86, PKEY_DISABLE_READ disables read and write on the key.
+ Powerpc, PKEY_DISABLE_READ just disables read.
+ PKEY_DISABLE_WRITE has to be specified explicitly to disable write.
+
+c) changing the permission bits of a key from a signal handler does not
+ persist on x86. The PKRU specific fpregs entry needs to be modified
+ for it to persist. On powerpc the permission bits of the key can be
+ modified by programming the AMR register from the signal handler.
+ The changes persists across signal boundaries.
+
+=====================================================================
--
1.8.3.1

2017-06-27 10:13:15

by Ram Pai

Subject: [RFC v4 14/17] selftest: PowerPC specific test updates to memory protection keys

Abstracted out the arch specific code into the header file, and
added powerpc specific changes.

a) added 4k-backed hpte, memory allocator, powerpc specific.
b) added three test case where the key is associated after the page is
accessed/allocated/mapped.
c) cleaned up the code to make checkpatch.pl happy

Signed-off-by: Ram Pai <[email protected]>
---
tools/testing/selftests/vm/pkey-helpers.h | 230 +++++++++--
tools/testing/selftests/vm/protection_keys.c | 567 ++++++++++++++++-----------
2 files changed, 518 insertions(+), 279 deletions(-)

diff --git a/tools/testing/selftests/vm/pkey-helpers.h b/tools/testing/selftests/vm/pkey-helpers.h
index b202939..69bfa89 100644
--- a/tools/testing/selftests/vm/pkey-helpers.h
+++ b/tools/testing/selftests/vm/pkey-helpers.h
@@ -12,13 +12,72 @@
#include <ucontext.h>
#include <sys/mman.h>

-#define NR_PKEYS 16
-#define PKRU_BITS_PER_PKEY 2
+/* Define some kernel-like types */
+#define u8 uint8_t
+#define u16 uint16_t
+#define u32 uint32_t
+#define u64 uint64_t
+
+#ifdef __i386__ /* arch */
+
+#define SYS_mprotect_key 380
+#define SYS_pkey_alloc 381
+#define SYS_pkey_free 382
+#define REG_IP_IDX REG_EIP
+#define si_pkey_offset 0x14
+
+#define NR_PKEYS 16
+#define NR_RESERVED_PKEYS 1
+#define PKRU_BITS_PER_PKEY 2
+#define PKEY_DISABLE_ACCESS 0x1
+#define PKEY_DISABLE_WRITE 0x2
+#define HPAGE_SIZE (1UL<<21)
+
+#define INIT_PRKU 0x0UL
+
+#elif __powerpc64__ /* arch */
+
+#define SYS_mprotect_key 386
+#define SYS_pkey_alloc 384
+#define SYS_pkey_free 385
+#define si_pkey_offset 0x20
+#define REG_IP_IDX PT_NIP
+#define REG_TRAPNO PT_TRAP
+#define REG_AMR 45
+#define gregs gp_regs
+#define fpregs fp_regs
+
+#define NR_PKEYS 32
+#define NR_RESERVED_PKEYS 3
+#define PKRU_BITS_PER_PKEY 2
+#define PKEY_DISABLE_ACCESS 0x3 /* disable read and write */
+#define PKEY_DISABLE_WRITE 0x2
+#define HPAGE_SIZE (1UL<<24)
+
+#define INIT_PRKU 0x3UL
+#else /* arch */
+
+ NOT SUPPORTED
+
+#endif /* arch */
+

#ifndef DEBUG_LEVEL
#define DEBUG_LEVEL 0
#endif
#define DPRINT_IN_SIGNAL_BUF_SIZE 4096
+
+
+static inline u32 pkey_to_shift(int pkey)
+{
+#ifdef __i386__ /* arch */
+ return pkey * PKRU_BITS_PER_PKEY;
+#elif __powerpc64__ /* arch */
+ return (NR_PKEYS - pkey - 1) * PKRU_BITS_PER_PKEY;
+#endif /* arch */
+}
+
+
extern int dprint_in_signal;
extern char dprint_in_signal_buffer[DPRINT_IN_SIGNAL_BUF_SIZE];
static inline void sigsafe_printf(const char *format, ...)
@@ -53,53 +112,76 @@ static inline void sigsafe_printf(const char *format, ...)
#define dprintf3(args...) dprintf_level(3, args)
#define dprintf4(args...) dprintf_level(4, args)

-extern unsigned int shadow_pkru;
-static inline unsigned int __rdpkru(void)
+extern u64 shadow_pkey_reg;
+
+static inline u64 __rdpkey_reg(void)
{
+#ifdef __i386__ /* arch */
unsigned int eax, edx;
unsigned int ecx = 0;
- unsigned int pkru;
+ unsigned int pkey_reg;

asm volatile(".byte 0x0f,0x01,0xee\n\t"
: "=a" (eax), "=d" (edx)
: "c" (ecx));
- pkru = eax;
- return pkru;
+#elif __powerpc64__ /* arch */
+ u64 eax;
+ u64 pkey_reg;
+
+ asm volatile("mfspr %0, 0xd" : "=r" ((u64)(eax)));
+#endif /* arch */
+ pkey_reg = (u64)eax;
+ return pkey_reg;
}

-static inline unsigned int _rdpkru(int line)
+static inline u64 _rdpkey_reg(int line)
{
- unsigned int pkru = __rdpkru();
+ u64 pkey_reg = __rdpkey_reg();

- dprintf4("rdpkru(line=%d) pkru: %x shadow: %x\n",
- line, pkru, shadow_pkru);
- assert(pkru == shadow_pkru);
+ dprintf4("rdpkey_reg(line=%d) pkey_reg: %lx shadow: %lx\n",
+ line, pkey_reg, shadow_pkey_reg);
+ assert(pkey_reg == shadow_pkey_reg);

- return pkru;
+ return pkey_reg;
}

-#define rdpkru() _rdpkru(__LINE__)
+#define rdpkey_reg() _rdpkey_reg(__LINE__)

-static inline void __wrpkru(unsigned int pkru)
+static inline void __wrpkey_reg(u64 pkey_reg)
{
- unsigned int eax = pkru;
+#ifdef __i386__ /* arch */
+ unsigned int eax = pkey_reg;
unsigned int ecx = 0;
unsigned int edx = 0;

- dprintf4("%s() changing %08x to %08x\n", __func__, __rdpkru(), pkru);
+ dprintf4("%s() changing %lx to %lx\n",
+ __func__, __rdpkey_reg(), pkey_reg);
asm volatile(".byte 0x0f,0x01,0xef\n\t"
: : "a" (eax), "c" (ecx), "d" (edx));
- assert(pkru == __rdpkru());
+ dprintf4("%s() PKRUP after changing %lx to %lx\n",
+ __func__, __rdpkey_reg(), pkey_reg);
+#else /* arch */
+ u64 eax = pkey_reg;
+
+ dprintf4("%s() changing %llx to %llx\n",
+ __func__, __rdpkey_reg(), pkey_reg);
+ asm volatile("mtspr 0xd, %0" : : "r" ((unsigned long)(eax)) : "memory");
+ dprintf4("%s() PKRUP after changing %llx to %llx\n",
+ __func__, __rdpkey_reg(), pkey_reg);
+#endif /* arch */
+ assert(pkey_reg == __rdpkey_reg());
}

-static inline void wrpkru(unsigned int pkru)
+static inline void wrpkey_reg(u64 pkey_reg)
{
- dprintf4("%s() changing %08x to %08x\n", __func__, __rdpkru(), pkru);
+ dprintf4("%s() changing %lx to %lx\n",
+ __func__, __rdpkey_reg(), pkey_reg);
/* will do the shadow check for us: */
- rdpkru();
- __wrpkru(pkru);
- shadow_pkru = pkru;
- dprintf4("%s(%08x) pkru: %08x\n", __func__, pkru, __rdpkru());
+ rdpkey_reg();
+ __wrpkey_reg(pkey_reg);
+ shadow_pkey_reg = pkey_reg;
+ dprintf4("%s(%lx) pkey_reg: %lx\n",
+ __func__, pkey_reg, __rdpkey_reg());
}

/*
@@ -108,40 +190,37 @@ static inline void wrpkru(unsigned int pkru)
*/
static inline void __pkey_access_allow(int pkey, int do_allow)
{
- unsigned int pkru = rdpkru();
+ u64 pkey_reg = rdpkey_reg();
int bit = pkey * 2;

if (do_allow)
- pkru &= (1<<bit);
+ pkey_reg &= (1<<bit);
else
- pkru |= (1<<bit);
+ pkey_reg |= (1<<bit);

- dprintf4("pkru now: %08x\n", rdpkru());
- wrpkru(pkru);
+ dprintf4("pkey_reg now: %lx\n", rdpkey_reg());
+ wrpkey_reg(pkey_reg);
}

static inline void __pkey_write_allow(int pkey, int do_allow_write)
{
- long pkru = rdpkru();
+ u64 pkey_reg = rdpkey_reg();
int bit = pkey * 2 + 1;

if (do_allow_write)
- pkru &= (1<<bit);
+ pkey_reg &= (1<<bit);
else
- pkru |= (1<<bit);
+ pkey_reg |= (1<<bit);

- wrpkru(pkru);
- dprintf4("pkru now: %08x\n", rdpkru());
+ wrpkey_reg(pkey_reg);
+ dprintf4("pkey_reg now: %lx\n", rdpkey_reg());
}

-#define PROT_PKEY0 0x10 /* protection key value (bit 0) */
-#define PROT_PKEY1 0x20 /* protection key value (bit 1) */
-#define PROT_PKEY2 0x40 /* protection key value (bit 2) */
-#define PROT_PKEY3 0x80 /* protection key value (bit 3) */
-
-#define PAGE_SIZE 4096
#define MB (1<<20)

+#ifdef __i386__ /* arch */
+
+#define PAGE_SIZE 4096
static inline void __cpuid(unsigned int *eax, unsigned int *ebx,
unsigned int *ecx, unsigned int *edx)
{
@@ -159,7 +238,7 @@ static inline void __cpuid(unsigned int *eax, unsigned int *ebx,
#define X86_FEATURE_PKU (1<<3) /* Protection Keys for Userspace */
#define X86_FEATURE_OSPKE (1<<4) /* OS Protection Keys Enable */

-static inline int cpu_has_pku(void)
+static inline int cpu_has_pkey(void)
{
unsigned int eax;
unsigned int ebx;
@@ -183,7 +262,6 @@ static inline int cpu_has_pku(void)

#define XSTATE_PKRU_BIT (9)
#define XSTATE_PKRU 0x200
-
int pkru_xstate_offset(void)
{
unsigned int eax;
@@ -216,4 +294,72 @@ int pkru_xstate_offset(void)
return xstate_offset;
}

+/* 8-bytes of instruction * 512 bytes = 1 page */
+#define __page_o_noops() asm(".rept 512 ; nopl 0x7eeeeeee(%eax) ; .endr")
+
+#elif __powerpc64__ /* arch */
+
+#define PAGE_SIZE (0x1UL << 16)
+static inline int cpu_has_pkey(void)
+{
+ return 1;
+}
+
+/* 8-bytes of instruction * 16384bytes = 1 page */
+#define __page_o_noops() asm(".rept 16384 ; nop; .endr")
+
+#endif /* arch */
+
+#define ARRAY_SIZE(x) (sizeof(x) / sizeof(*(x)))
+#define ALIGN_UP(x, align_to) (((x) + ((align_to)-1)) & ~((align_to)-1))
+#define ALIGN_DOWN(x, align_to) ((x) & ~((align_to)-1))
+#define ALIGN_PTR_UP(p, ptr_align_to) \
+ ((typeof(p))ALIGN_UP((unsigned long)(p), ptr_align_to))
+#define ALIGN_PTR_DOWN(p, ptr_align_to) \
+ ((typeof(p))ALIGN_DOWN((unsigned long)(p), ptr_align_to))
+#define __stringify_1(x...) #x
+#define __stringify(x...) __stringify_1(x)
+
+#define PTR_ERR_ENOTSUP ((void *)-ENOTSUP)
+
+extern void abort_hooks(void);
+#define pkey_assert(condition) do { \
+ if (!(condition)) { \
+ dprintf0("assert() at %s::%d test_nr: %d iteration: %d\n", \
+ __FILE__, __LINE__, \
+ test_nr, iteration_nr); \
+ dprintf0("errno at assert: %d", errno); \
+ abort_hooks(); \
+ assert(condition); \
+ } \
+} while (0)
+#define raw_assert(cond) assert(cond)
+
+
+static inline int open_hugepage_file(int flag)
+{
+ int fd;
+#ifdef __i386__ /* arch */
+ fd = open("/sys/kernel/mm/hugepages/hugepages-2048kB/nr_hugepages",
+ O_RDONLY);
+#elif __powerpc64__ /* arch */
+ fd = open("/sys/kernel/mm/hugepages/hugepages-16384kB/nr_hugepages",
+ O_RDONLY);
+#else /* arch */
+ NOT SUPPORTED
+#endif /* arch */
+ return fd;
+}
+
+static inline int get_start_key(void)
+{
+#ifdef __i386__ /* arch */
+ return 1;
+#elif __powerpc64__ /* arch */
+ return 0;
+#else /* arch */
+ NOT SUPPORTED
+#endif /* arch */
+}
+
#endif /* _PKEYS_HELPER_H */
diff --git a/tools/testing/selftests/vm/protection_keys.c b/tools/testing/selftests/vm/protection_keys.c
index 3237bc0..bba1857 100644
--- a/tools/testing/selftests/vm/protection_keys.c
+++ b/tools/testing/selftests/vm/protection_keys.c
@@ -1,10 +1,10 @@
/*
- * Tests x86 Memory Protection Keys (see Documentation/x86/protection-keys.txt)
+ * Tests Memory Protection Keys (see Documentation/vm/protection-keys.txt)
*
* There are examples in here of:
* * how to set protection keys on memory
- * * how to set/clear bits in PKRU (the rights register)
- * * how to handle SEGV_PKRU signals and extract pkey-relevant
+ * * how to set/clear bits in Protection Key registers (the rights register)
+ * * how to handle SEGV_PKUERR signals and extract pkey-relevant
* information from the siginfo
*
* Things to add:
@@ -12,17 +12,23 @@
* prefault pages in at malloc, or not
* protect MPX bounds tables with protection keys?
* make sure VMA splitting/merging is working correctly
- * OOMs can destroy mm->mmap (see exit_mmap()), so make sure it is immune to pkeys
- * look for pkey "leaks" where it is still set on a VMA but "freed" back to the kernel
- * do a plain mprotect() to a mprotect_pkey() area and make sure the pkey sticks
+ * OOMs can destroy mm->mmap (see exit_mmap()),
+ * so make sure it is immune to pkeys
+ * look for pkey "leaks" where it is still set on a VMA
+ * but "freed" back to the kernel
+ * do a plain mprotect() to a mprotect_pkey() area and make
+ * sure the pkey sticks
*
* Compile like this:
- * gcc -o protection_keys -O2 -g -std=gnu99 -pthread -Wall protection_keys.c -lrt -ldl -lm
- * gcc -m32 -o protection_keys_32 -O2 -g -std=gnu99 -pthread -Wall protection_keys.c -lrt -ldl -lm
+ * gcc -o protection_keys -O2 -g -std=gnu99
+ * -pthread -Wall protection_keys.c -lrt -ldl -lm
+ * gcc -m32 -o protection_keys_32 -O2 -g -std=gnu99
+ * -pthread -Wall protection_keys.c -lrt -ldl -lm
*/
#define _GNU_SOURCE
#include <errno.h>
#include <linux/futex.h>
+#include <time.h>
#include <sys/time.h>
#include <sys/syscall.h>
#include <string.h>
@@ -46,36 +52,11 @@

int iteration_nr = 1;
int test_nr;
-
-unsigned int shadow_pkru;
-
-#define HPAGE_SIZE (1UL<<21)
-#define ARRAY_SIZE(x) (sizeof(x) / sizeof(*(x)))
-#define ALIGN_UP(x, align_to) (((x) + ((align_to)-1)) & ~((align_to)-1))
-#define ALIGN_DOWN(x, align_to) ((x) & ~((align_to)-1))
-#define ALIGN_PTR_UP(p, ptr_align_to) ((typeof(p))ALIGN_UP((unsigned long)(p), ptr_align_to))
-#define ALIGN_PTR_DOWN(p, ptr_align_to) ((typeof(p))ALIGN_DOWN((unsigned long)(p), ptr_align_to))
-#define __stringify_1(x...) #x
-#define __stringify(x...) __stringify_1(x)
-
-#define PTR_ERR_ENOTSUP ((void *)-ENOTSUP)
+u64 shadow_pkey_reg;

int dprint_in_signal;
char dprint_in_signal_buffer[DPRINT_IN_SIGNAL_BUF_SIZE];

-extern void abort_hooks(void);
-#define pkey_assert(condition) do { \
- if (!(condition)) { \
- dprintf0("assert() at %s::%d test_nr: %d iteration: %d\n", \
- __FILE__, __LINE__, \
- test_nr, iteration_nr); \
- dprintf0("errno at assert: %d", errno); \
- abort_hooks(); \
- assert(condition); \
- } \
-} while (0)
-#define raw_assert(cond) assert(cond)
-
void cat_into_file(char *str, char *file)
{
int fd = open(file, O_RDWR);
@@ -153,11 +134,6 @@ void abort_hooks(void)
#endif
}

-static inline void __page_o_noops(void)
-{
- /* 8-bytes of instruction * 512 bytes = 1 page */
- asm(".rept 512 ; nopl 0x7eeeeeee(%eax) ; .endr");
-}

/*
* This attempts to have roughly a page of instructions followed by a few
@@ -181,26 +157,6 @@ void lots_o_noops_around_write(int *write_to_me)
dprintf3("%s() done\n", __func__);
}

-/* Define some kernel-like types */
-#define u8 uint8_t
-#define u16 uint16_t
-#define u32 uint32_t
-#define u64 uint64_t
-
-#ifdef __i386__
-#define SYS_mprotect_key 380
-#define SYS_pkey_alloc 381
-#define SYS_pkey_free 382
-#define REG_IP_IDX REG_EIP
-#define si_pkey_offset 0x14
-#else
-#define SYS_mprotect_key 329
-#define SYS_pkey_alloc 330
-#define SYS_pkey_free 331
-#define REG_IP_IDX REG_RIP
-#define si_pkey_offset 0x20
-#endif
-
void dump_mem(void *dumpme, int len_bytes)
{
char *c = (void *)dumpme;
@@ -208,6 +164,7 @@ void dump_mem(void *dumpme, int len_bytes)

for (i = 0; i < len_bytes; i += sizeof(u64)) {
u64 *ptr = (u64 *)(c + i);
+
dprintf1("dump[%03d][@%p]: %016jx\n", i, ptr, *ptr);
}
}
@@ -229,29 +186,49 @@ static char *si_code_str(int si_code)
return "UNKNOWN";
}

-int pkru_faults;
+int pkey_faults;
int last_si_pkey = -1;
+
+u64 reset_bits(int pkey, u64 bits)
+{
+ u32 shift = pkey_to_shift(pkey);
+
+ return ~(bits << shift);
+}
+
+u64 left_shift_bits(int pkey, u64 bits)
+{
+ u32 shift = pkey_to_shift(pkey);
+
+ return (bits << shift);
+}
+
+u64 right_shift_bits(int pkey, u64 bits)
+{
+ u32 shift = pkey_to_shift(pkey);
+
+ return (bits >> shift);
+}
+
+void pkey_access_allow(int pkey);
void signal_handler(int signum, siginfo_t *si, void *vucontext)
{
ucontext_t *uctxt = vucontext;
int trapno;
unsigned long ip;
char *fpregs;
- u32 *pkru_ptr;
+ u64 *pkey_reg_ptr;
u64 si_pkey;
u32 *si_pkey_ptr;
- int pkru_offset;
- fpregset_t fpregset;

dprint_in_signal = 1;
dprintf1(">>>>===============SIGSEGV============================\n");
- dprintf1("%s()::%d, pkru: 0x%x shadow: %x\n", __func__, __LINE__,
- __rdpkru(), shadow_pkru);
+ dprintf1("%s()::%d, pkey_reg: 0x%lx shadow: %lx\n", __func__, __LINE__,
+ __rdpkey_reg(), shadow_pkey_reg);

trapno = uctxt->uc_mcontext.gregs[REG_TRAPNO];
ip = uctxt->uc_mcontext.gregs[REG_IP_IDX];
- fpregset = uctxt->uc_mcontext.fpregs;
- fpregs = (void *)fpregset;
+ fpregs = (char *) uctxt->uc_mcontext.fpregs;

dprintf2("%s() trapno: %d ip: 0x%lx info->si_code: %s/%d\n", __func__,
trapno, ip, si_code_str(si->si_code), si->si_code);
@@ -262,20 +239,22 @@ void signal_handler(int signum, siginfo_t *si, void *vucontext)
* state. We just assume that it is here.
*/
fpregs += 0x70;
-#endif
- pkru_offset = pkru_xstate_offset();
- pkru_ptr = (void *)(&fpregs[pkru_offset]);
-
- dprintf1("siginfo: %p\n", si);
- dprintf1(" fpregs: %p\n", fpregs);
+ pkey_reg_ptr = (void *)(&fpregs[pkru_xstate_offset()]);
/*
- * If we got a PKRU fault, we *HAVE* to have at least one bit set in
+ * If we got a key fault, we *HAVE* to have at least one bit set in
* here.
*/
dprintf1("pkru_xstate_offset: %d\n", pkru_xstate_offset());
if (DEBUG_LEVEL > 4)
- dump_mem(pkru_ptr - 128, 256);
- pkey_assert(*pkru_ptr);
+ dump_mem(pkey_reg_ptr - 128, 256);
+#elif __powerpc64__
+ pkey_reg_ptr = &uctxt->uc_mcontext.gregs[REG_AMR];
+#endif
+
+
+ dprintf1("siginfo: %p\n", si);
+ dprintf1(" fpregs: %p\n", fpregs);
+ pkey_assert(*pkey_reg_ptr);

si_pkey_ptr = (u32 *)(((u8 *)si) + si_pkey_offset);
dprintf1("si_pkey_ptr: %p\n", si_pkey_ptr);
@@ -291,36 +270,29 @@ void signal_handler(int signum, siginfo_t *si, void *vucontext)
exit(4);
}

- dprintf1("signal pkru from xsave: %08x\n", *pkru_ptr);
- /* need __rdpkru() version so we do not do shadow_pkru checking */
- dprintf1("signal pkru from pkru: %08x\n", __rdpkru());
+ dprintf1("signal pkey_reg : %08x\n", *pkey_reg_ptr);
+ /*
+ * need __rdpkey_reg() version so we do not do
+ * shadow_pkey_reg checking
+ */
+ dprintf1("signal pkey_reg from pkey_reg: %08x\n", __rdpkey_reg());
dprintf1("si_pkey from siginfo: %jx\n", si_pkey);
- *(u64 *)pkru_ptr = 0x00000000;
- dprintf1("WARNING: set PRKU=0 to allow faulting instruction to continue\n");
- pkru_faults++;
+#ifdef __i386__
+ *(u64 *)pkey_reg_ptr &= reset_bits(si_pkey, PKEY_DISABLE_ACCESS);
+#elif __powerpc64__
+ pkey_access_allow(si_pkey);
+#endif
+ shadow_pkey_reg &= reset_bits(si_pkey, PKEY_DISABLE_ACCESS);
+ dprintf1("WARNING: set PRKU=0 to allow faulting instruction "
+ "to continue\n");
+ pkey_faults++;
dprintf1("<<<<==================================================\n");
- return;
- if (trapno == 14) {
- fprintf(stderr,
- "ERROR: In signal handler, page fault, trapno = %d, ip = %016lx\n",
- trapno, ip);
- fprintf(stderr, "si_addr %p\n", si->si_addr);
- fprintf(stderr, "REG_ERR: %lx\n",
- (unsigned long)uctxt->uc_mcontext.gregs[REG_ERR]);
- exit(1);
- } else {
- fprintf(stderr, "unexpected trap %d! at 0x%lx\n", trapno, ip);
- fprintf(stderr, "si_addr %p\n", si->si_addr);
- fprintf(stderr, "REG_ERR: %lx\n",
- (unsigned long)uctxt->uc_mcontext.gregs[REG_ERR]);
- exit(2);
- }
- dprint_in_signal = 0;
}

int wait_all_children(void)
{
int status;
+
return waitpid(-1, &status, 0);
}

@@ -409,51 +381,50 @@ void dumpit(char *f)
close(fd);
}

-#define PKEY_DISABLE_ACCESS 0x1
-#define PKEY_DISABLE_WRITE 0x2
-
-u32 pkey_get(int pkey, unsigned long flags)
+u64 pkey_get(int pkey, unsigned long flags)
{
- u32 mask = (PKEY_DISABLE_ACCESS|PKEY_DISABLE_WRITE);
- u32 pkru = __rdpkru();
- u32 shifted_pkru;
- u32 masked_pkru;
+ u64 mask = (PKEY_DISABLE_ACCESS|PKEY_DISABLE_WRITE);
+ u64 pkey_reg = __rdpkey_reg();
+ u64 shifted_pkey_reg;
+ u64 masked_pkey_reg;

dprintf1("%s(pkey=%d, flags=%lx) = %x / %d\n",
__func__, pkey, flags, 0, 0);
- dprintf2("%s() raw pkru: %x\n", __func__, pkru);
+ dprintf2("%s() raw pkey_reg: %lx\n", __func__, pkey_reg);

- shifted_pkru = (pkru >> (pkey * PKRU_BITS_PER_PKEY));
- dprintf2("%s() shifted_pkru: %x\n", __func__, shifted_pkru);
- masked_pkru = shifted_pkru & mask;
- dprintf2("%s() masked pkru: %x\n", __func__, masked_pkru);
+ shifted_pkey_reg = right_shift_bits(pkey, pkey_reg);
+ dprintf2("%s() shifted_pkey_reg: %lx\n", __func__, shifted_pkey_reg);
+ masked_pkey_reg = shifted_pkey_reg & mask;
+ dprintf2("%s() masked pkey_reg: %lx\n", __func__, masked_pkey_reg);
/*
* shift down the relevant bits to the lowest two, then
* mask off all the other high bits.
*/
- return masked_pkru;
+ return masked_pkey_reg;
}

int pkey_set(int pkey, unsigned long rights, unsigned long flags)
{
- u32 mask = (PKEY_DISABLE_ACCESS|PKEY_DISABLE_WRITE);
- u32 old_pkru = __rdpkru();
- u32 new_pkru;
+ u64 mask = (PKEY_DISABLE_ACCESS|PKEY_DISABLE_WRITE);
+ u64 old_pkey_reg = __rdpkey_reg();
+ u64 new_pkey_reg;

/* make sure that 'rights' only contains the bits we expect: */
assert(!(rights & ~mask));

- /* copy old pkru */
- new_pkru = old_pkru;
+ /* copy old pkey_reg */
+ new_pkey_reg = old_pkey_reg;
/* mask out bits from pkey in old value: */
- new_pkru &= ~(mask << (pkey * PKRU_BITS_PER_PKEY));
+ new_pkey_reg &= reset_bits(pkey, mask);
/* OR in new bits for pkey: */
- new_pkru |= (rights << (pkey * PKRU_BITS_PER_PKEY));
+ new_pkey_reg |= left_shift_bits(pkey, rights);

- __wrpkru(new_pkru);
+ __wrpkey_reg(new_pkey_reg);

- dprintf3("%s(pkey=%d, rights=%lx, flags=%lx) = %x pkru now: %x old_pkru: %x\n",
- __func__, pkey, rights, flags, 0, __rdpkru(), old_pkru);
+ dprintf3("%s(pkey=%d, rights=%lx, flags=%lx) = %x "
+ "pkey_reg now: %x old_pkey_reg: %x\n",
+ __func__, pkey, rights, flags,
+ 0, __rdpkey_reg(), old_pkey_reg);
return 0;
}

@@ -461,8 +432,8 @@ void pkey_disable_set(int pkey, int flags)
{
unsigned long syscall_flags = 0;
int ret;
- int pkey_rights;
- u32 orig_pkru = rdpkru();
+ u64 pkey_rights;
+ u64 orig_pkey_reg = rdpkey_reg();

dprintf1("START->%s(%d, 0x%x)\n", __func__,
pkey, flags);
@@ -474,23 +445,28 @@ void pkey_disable_set(int pkey, int flags)
pkey, pkey, pkey_rights);
pkey_assert(pkey_rights >= 0);

- pkey_rights |= flags;
+ /* process flags only if they have some new bits enabled */
+ if (flags && !(pkey_rights & flags)) {
+ pkey_rights |= flags;

- ret = pkey_set(pkey, pkey_rights, syscall_flags);
- assert(!ret);
- /*pkru and flags have the same format */
- shadow_pkru |= flags << (pkey * 2);
- dprintf1("%s(%d) shadow: 0x%x\n", __func__, pkey, shadow_pkru);
+ ret = pkey_set(pkey, pkey_rights, syscall_flags);
+ assert(!ret);
+ /*pkey_reg and flags have the same format */
+ shadow_pkey_reg |= left_shift_bits(pkey, flags);
+ dprintf1("%s(%d) shadow: 0x%x\n",
+ __func__, pkey, shadow_pkey_reg);

- pkey_assert(ret >= 0);
+ pkey_assert(ret >= 0);

- pkey_rights = pkey_get(pkey, syscall_flags);
- dprintf1("%s(%d) pkey_get(%d): %x\n", __func__,
- pkey, pkey, pkey_rights);
+ pkey_rights = pkey_get(pkey, syscall_flags);
+ dprintf1("%s(%d) pkey_get(%d): %x\n", __func__,
+ pkey, pkey, pkey_rights);

- dprintf1("%s(%d) pkru: 0x%x\n", __func__, pkey, rdpkru());
- if (flags)
- pkey_assert(rdpkru() > orig_pkru);
+ dprintf1("%s(%d) pkey_reg: 0x%lx\n",
+ __func__, pkey, rdpkey_reg());
+ if (flags)
+ pkey_assert(rdpkey_reg() > orig_pkey_reg);
+ }
dprintf1("END<---%s(%d, 0x%x)\n", __func__,
pkey, flags);
}
@@ -499,8 +475,8 @@ void pkey_disable_clear(int pkey, int flags)
{
unsigned long syscall_flags = 0;
int ret;
- int pkey_rights = pkey_get(pkey, syscall_flags);
- u32 orig_pkru = rdpkru();
+ u64 pkey_rights = pkey_get(pkey, syscall_flags);
+ u64 orig_pkey_reg = rdpkey_reg();

pkey_assert(flags & (PKEY_DISABLE_ACCESS | PKEY_DISABLE_WRITE));

@@ -508,20 +484,21 @@ void pkey_disable_clear(int pkey, int flags)
pkey, pkey, pkey_rights);
pkey_assert(pkey_rights >= 0);

- pkey_rights |= flags;
+ pkey_rights &= ~flags;

ret = pkey_set(pkey, pkey_rights, 0);
- /* pkru and flags have the same format */
- shadow_pkru &= ~(flags << (pkey * 2));
+ /* pkey_reg and flags have the same format */
+ shadow_pkey_reg &= reset_bits(pkey, flags);
pkey_assert(ret >= 0);

pkey_rights = pkey_get(pkey, syscall_flags);
dprintf1("%s(%d) pkey_get(%d): %x\n", __func__,
pkey, pkey, pkey_rights);

- dprintf1("%s(%d) pkru: 0x%x\n", __func__, pkey, rdpkru());
+ dprintf1("%s(%d) pkey_reg: 0x%x\n",
+ __func__, pkey, rdpkey_reg());
if (flags)
- assert(rdpkru() > orig_pkru);
+ assert(rdpkey_reg() > orig_pkey_reg);
}

void pkey_write_allow(int pkey)
@@ -564,49 +541,72 @@ int sys_mprotect_pkey(void *ptr, size_t size, unsigned long orig_prot,
int sys_pkey_alloc(unsigned long flags, unsigned long init_val)
{
int ret = syscall(SYS_pkey_alloc, flags, init_val);
+
dprintf1("%s(flags=%lx, init_val=%lx) syscall ret: %d errno: %d\n",
__func__, flags, init_val, ret, errno);
return ret;
}

+void pkey_setup_shadow(void)
+{
+ shadow_pkey_reg = __rdpkey_reg();
+}
+
+void pkey_reset_shadow(u32 key)
+{
+ shadow_pkey_reg &= reset_bits(key, 0x3);
+}
+
+void pkey_set_shadow(u32 key, u64 init_val)
+{
+ shadow_pkey_reg |= left_shift_bits(key, init_val);
+}
+
int alloc_pkey(void)
{
int ret;
- unsigned long init_val = 0x0;
+ u64 init_val = 0x0;

- dprintf1("alloc_pkey()::%d, pkru: 0x%x shadow: %x\n",
- __LINE__, __rdpkru(), shadow_pkru);
+ dprintf1("%s()::%d, pkey_reg: 0x%x shadow: %x\n",
+ __func__, __LINE__, __rdpkey_reg(),
+ shadow_pkey_reg);
ret = sys_pkey_alloc(0, init_val);
/*
- * pkey_alloc() sets PKRU, so we need to reflect it in
- * shadow_pkru:
+ * pkey_alloc() sets pkey register, so we need to reflect it in
+ * shadow_pkey_reg:
*/
- dprintf4("alloc_pkey()::%d, ret: %d pkru: 0x%x shadow: 0x%x\n",
- __LINE__, ret, __rdpkru(), shadow_pkru);
+ dprintf4("%s()::%d, ret: %d pkey_reg: 0x%x shadow: 0x%x\n",
+ __func__, __LINE__, ret, __rdpkey_reg(),
+ shadow_pkey_reg);
if (ret) {
/* clear both the bits: */
- shadow_pkru &= ~(0x3 << (ret * 2));
- dprintf4("alloc_pkey()::%d, ret: %d pkru: 0x%x shadow: 0x%x\n",
- __LINE__, ret, __rdpkru(), shadow_pkru);
+ pkey_reset_shadow(ret);
+ dprintf4("%s()::%d, ret: %d pkey_reg: 0x%x shadow:"
+ " 0x%x\n",
+ __func__, __LINE__, ret,
+ __rdpkey_reg(), shadow_pkey_reg);
/*
* move the new state in from init_val
- * (remember, we cheated and init_val == pkru format)
+ * (remember, we cheated and init_val == pkey_reg format)
*/
- shadow_pkru |= (init_val << (ret * 2));
+ pkey_set_shadow(ret, init_val);
}
- dprintf4("alloc_pkey()::%d, ret: %d pkru: 0x%x shadow: 0x%x\n",
- __LINE__, ret, __rdpkru(), shadow_pkru);
- dprintf1("alloc_pkey()::%d errno: %d\n", __LINE__, errno);
+ dprintf4("%s()::%d, ret: %d pkey_reg: 0x%x shadow: 0x%x\n",
+ __func__, __LINE__, ret, __rdpkey_reg(),
+ shadow_pkey_reg);
+ dprintf1("%s()::%d errno: %d\n", __func__, __LINE__, errno);
/* for shadow checking: */
- rdpkru();
- dprintf4("alloc_pkey()::%d, ret: %d pkru: 0x%x shadow: 0x%x\n",
- __LINE__, ret, __rdpkru(), shadow_pkru);
+ rdpkey_reg();
+ dprintf4("%s()::%d, ret: %d pkey_reg: 0x%x shadow: 0x%x\n",
+ __func__, __LINE__, ret, __rdpkey_reg(),
+ shadow_pkey_reg);
return ret;
}

int sys_pkey_free(unsigned long pkey)
{
int ret = syscall(SYS_pkey_free, pkey);
+
dprintf1("%s(pkey=%ld) syscall ret: %d\n", __func__, pkey, ret);
return ret;
}
@@ -624,13 +624,15 @@ int alloc_random_pkey(void)
int alloced_pkeys[NR_PKEYS];
int nr_alloced = 0;
int random_index;
+
memset(alloced_pkeys, 0, sizeof(alloced_pkeys));
+ srand((unsigned int)time(NULL));

/* allocate every possible key and make a note of which ones we got */
max_nr_pkey_allocs = NR_PKEYS;
- max_nr_pkey_allocs = 1;
for (i = 0; i < max_nr_pkey_allocs; i++) {
int new_pkey = alloc_pkey();
+
if (new_pkey < 0)
break;
alloced_pkeys[nr_alloced++] = new_pkey;
@@ -646,13 +648,14 @@ int alloc_random_pkey(void)
/* go through the allocated ones that we did not want and free them */
for (i = 0; i < nr_alloced; i++) {
int free_ret;
+
if (!alloced_pkeys[i])
continue;
free_ret = sys_pkey_free(alloced_pkeys[i]);
pkey_assert(!free_ret);
}
- dprintf1("%s()::%d, ret: %d pkru: 0x%x shadow: 0x%x\n", __func__,
- __LINE__, ret, __rdpkru(), shadow_pkru);
+ dprintf1("%s()::%d, ret: %d pkey_reg: 0x%x shadow: 0x%x\n", __func__,
+ __LINE__, ret, __rdpkey_reg(), shadow_pkey_reg);
return ret;
}

@@ -664,17 +667,22 @@ int mprotect_pkey(void *ptr, size_t size, unsigned long orig_prot,

while (0) {
int rpkey = alloc_random_pkey();
+
ret = sys_mprotect_pkey(ptr, size, orig_prot, pkey);
- dprintf1("sys_mprotect_pkey(%p, %zx, prot=0x%lx, pkey=%ld) ret: %d\n",
+
+ dprintf1("sys_mprotect_pkey(%p, %zx, prot=0x%lx, pkey=%ld) "
+ "ret: %d\n",
ptr, size, orig_prot, pkey, ret);
if (nr_iterations-- < 0)
break;

- dprintf1("%s()::%d, ret: %d pkru: 0x%x shadow: 0x%x\n", __func__,
- __LINE__, ret, __rdpkru(), shadow_pkru);
+ dprintf1("%s()::%d, ret: %d pkey_reg: 0x%x shadow: 0x%x\n",
+ __func__, __LINE__, ret, __rdpkey_reg(),
+ shadow_pkey_reg);
sys_pkey_free(rpkey);
- dprintf1("%s()::%d, ret: %d pkru: 0x%x shadow: 0x%x\n", __func__,
- __LINE__, ret, __rdpkru(), shadow_pkru);
+ dprintf1("%s()::%d, ret: %d pkey_reg: 0x%x shadow: 0x%x\n",
+ __func__, __LINE__, ret, __rdpkey_reg(),
+ shadow_pkey_reg);
}
pkey_assert(pkey < NR_PKEYS);

@@ -682,8 +690,8 @@ int mprotect_pkey(void *ptr, size_t size, unsigned long orig_prot,
dprintf1("mprotect_pkey(%p, %zx, prot=0x%lx, pkey=%ld) ret: %d\n",
ptr, size, orig_prot, pkey, ret);
pkey_assert(!ret);
- dprintf1("%s()::%d, ret: %d pkru: 0x%x shadow: 0x%x\n", __func__,
- __LINE__, ret, __rdpkru(), shadow_pkru);
+ dprintf1("%s()::%d, ret: %d pkey_reg: 0x%x shadow: 0x%x\n", __func__,
+ __LINE__, ret, __rdpkey_reg(), shadow_pkey_reg);
return ret;
}

@@ -708,7 +716,9 @@ void record_pkey_malloc(void *ptr, long size)
/* every record is full */
size_t old_nr_records = nr_pkey_malloc_records;
size_t new_nr_records = (nr_pkey_malloc_records * 2 + 1);
- size_t new_size = new_nr_records * sizeof(struct pkey_malloc_record);
+ size_t new_size = new_nr_records *
+ sizeof(struct pkey_malloc_record);
+
dprintf2("new_nr_records: %zd\n", new_nr_records);
dprintf2("new_size: %zd\n", new_size);
pkey_malloc_records = realloc(pkey_malloc_records, new_size);
@@ -732,9 +742,11 @@ void free_pkey_malloc(void *ptr)
{
long i;
int ret;
+
dprintf3("%s(%p)\n", __func__, ptr);
for (i = 0; i < nr_pkey_malloc_records; i++) {
struct pkey_malloc_record *rec = &pkey_malloc_records[i];
+
dprintf4("looking for ptr %p at record[%ld/%p]: {%p, %ld}\n",
ptr, i, rec, rec->ptr, rec->size);
if ((ptr < rec->ptr) ||
@@ -761,16 +773,46 @@ void *malloc_pkey_with_mprotect(long size, int prot, u16 pkey)
void *ptr;
int ret;

- rdpkru();
+ rdpkey_reg();
+ dprintf1("doing %s(size=%ld, prot=0x%x, pkey=%d)\n", __func__,
+ size, prot, pkey);
+ pkey_assert(pkey < NR_PKEYS);
+ ptr = mmap(NULL, size, prot, MAP_ANONYMOUS|MAP_PRIVATE, -1, 0);
+ pkey_assert(ptr != (void *)-1);
+ ret = mprotect_pkey((void *)ptr, PAGE_SIZE, prot, pkey);
+ pkey_assert(!ret);
+ record_pkey_malloc(ptr, size);
+ rdpkey_reg();
+
+ dprintf1("%s() for pkey %d @ %p\n", __func__, pkey, ptr);
+ return ptr;
+}
+
+void *malloc_pkey_with_mprotect_subpage(long size, int prot, u16 pkey)
+{
+ void *ptr;
+ int ret;
+
+#ifndef __powerpc64__
+ return PTR_ERR_ENOTSUP;
+#endif /* __powerpc64__ */
+ rdpkey_reg();
dprintf1("doing %s(size=%ld, prot=0x%x, pkey=%d)\n", __func__,
size, prot, pkey);
pkey_assert(pkey < NR_PKEYS);
ptr = mmap(NULL, size, prot, MAP_ANONYMOUS|MAP_PRIVATE, -1, 0);
pkey_assert(ptr != (void *)-1);
+
+ ret = syscall(__NR_subpage_prot, ptr, size, NULL);
+ if (ret) {
+ perror("subpage_perm");
+ return PTR_ERR_ENOTSUP;
+ }
+
ret = mprotect_pkey((void *)ptr, PAGE_SIZE, prot, pkey);
pkey_assert(!ret);
record_pkey_malloc(ptr, size);
- rdpkru();
+ rdpkey_reg();

dprintf1("%s() for pkey %d @ %p\n", __func__, pkey, ptr);
return ptr;
@@ -815,17 +857,19 @@ void setup_hugetlbfs(void)
char buf[] = "123";

if (geteuid() != 0) {
- fprintf(stderr, "WARNING: not run as root, can not do hugetlb test\n");
+ fprintf(stderr,
+ "WARNING: not run as root, can not do hugetlb test\n");
return;
}

- cat_into_file(__stringify(GET_NR_HUGE_PAGES), "/proc/sys/vm/nr_hugepages");
+ cat_into_file(__stringify(GET_NR_HUGE_PAGES),
+ "/proc/sys/vm/nr_hugepages");

/*
* Now go make sure that we got the pages and that they
* are 2M pages. Someone might have made 1G the default.
*/
- fd = open("/sys/kernel/mm/hugepages/hugepages-2048kB/nr_hugepages", O_RDONLY);
+ fd = open_hugepage_file(O_RDONLY);
if (fd < 0) {
perror("opening sysfs 2M hugetlb config");
return;
@@ -840,7 +884,8 @@ void setup_hugetlbfs(void)
}

if (atoi(buf) != GET_NR_HUGE_PAGES) {
- fprintf(stderr, "could not confirm 2M pages, got: '%s' expected %d\n",
+ fprintf(stderr, "could not confirm 2M pages, got:"
+ " '%s' expected %d\n",
buf, GET_NR_HUGE_PAGES);
return;
}
@@ -895,12 +940,13 @@ void *malloc_pkey_mmap_dax(long size, int prot, u16 pkey)
void *(*pkey_malloc[])(long size, int prot, u16 pkey) = {

malloc_pkey_with_mprotect,
+ malloc_pkey_with_mprotect_subpage,
malloc_pkey_anon_huge,
malloc_pkey_hugetlb
/* can not do direct with the pkey_mprotect() API:
- malloc_pkey_mmap_direct,
- malloc_pkey_mmap_dax,
-*/
+ * malloc_pkey_mmap_direct,
+ * malloc_pkey_mmap_dax,
+ */
};

void *malloc_pkey(long size, int prot, u16 pkey)
@@ -933,31 +979,32 @@ void *malloc_pkey(long size, int prot, u16 pkey)
return ret;
}

-int last_pkru_faults;
-void expected_pk_fault(int pkey)
+int last_pkey_faults;
+void expected_pkey_faults(int pkey)
{
- dprintf2("%s(): last_pkru_faults: %d pkru_faults: %d\n",
- __func__, last_pkru_faults, pkru_faults);
+ dprintf2("%s(): last_pkey_faults: %d pkey_faults: %d\n",
+ __func__, last_pkey_faults, pkey_faults);
dprintf2("%s(%d): last_si_pkey: %d\n", __func__, pkey, last_si_pkey);
- pkey_assert(last_pkru_faults + 1 == pkru_faults);
+ pkey_assert(last_pkey_faults + 1 == pkey_faults);
pkey_assert(last_si_pkey == pkey);
/*
- * The signal handler shold have cleared out PKRU to let the
+ * The signal handler shold have cleared out pkey-register to let the
* test program continue. We now have to restore it.
*/
- if (__rdpkru() != 0)
+ if (__rdpkey_reg() != shadow_pkey_reg)
pkey_assert(0);

- __wrpkru(shadow_pkru);
- dprintf1("%s() set PKRU=%x to restore state after signal nuked it\n",
- __func__, shadow_pkru);
- last_pkru_faults = pkru_faults;
+ __wrpkey_reg(shadow_pkey_reg);
+ dprintf1("%s() set pkey-register=%x to restore state "
+ " after signal nuked it\n",
+ __func__, shadow_pkey_reg);
+ last_pkey_faults = pkey_faults;
last_si_pkey = -1;
}

void do_not_expect_pk_fault(void)
{
- pkey_assert(last_pkru_faults == pkru_faults);
+ pkey_assert(last_pkey_faults == pkey_faults);
}

int test_fds[10] = { -1 };
@@ -973,6 +1020,7 @@ void __save_test_fd(int fd)
int get_test_read_fd(void)
{
int test_fd = open("/etc/passwd", O_RDONLY);
+
__save_test_fd(test_fd);
return test_fd;
}
@@ -1009,32 +1057,76 @@ void test_read_of_write_disabled_region(int *ptr, u16 pkey)
ptr_contents = read_ptr(ptr);
dprintf1("*ptr: %d\n", ptr_contents);
dprintf1("\n");
+ do_not_expect_pk_fault();
}
+
void test_read_of_access_disabled_region(int *ptr, u16 pkey)
{
int ptr_contents;

- dprintf1("disabling access to PKEY[%02d], doing read @ %p\n", pkey, ptr);
- rdpkru();
+ dprintf1("disabling access to PKEY[%02d], doing read @ %p\n",
+ pkey, ptr);
+ rdpkey_reg();
+ pkey_access_deny(pkey);
+ ptr_contents = read_ptr(ptr);
+ dprintf1("*ptr: %d\n", ptr_contents);
+ expected_pkey_faults(pkey);
+}
+
+void test_read_of_access_disabled_region_with_page_already_mapped(int *ptr,
+ u16 pkey)
+{
+ int ptr_contents;
+
+ dprintf1("disabling access to PKEY[%02d], doing read @ %p\n",
+ pkey, ptr);
+ ptr_contents = read_ptr(ptr);
+ dprintf1("reading ptr before disabling the read : %d\n",
+ ptr_contents);
+ rdpkey_reg();
pkey_access_deny(pkey);
ptr_contents = read_ptr(ptr);
dprintf1("*ptr: %d\n", ptr_contents);
- expected_pk_fault(pkey);
+ expected_pkey_faults(pkey);
}
+
+void test_write_of_write_disabled_region_with_page_already_mapped(int *ptr,
+ u16 pkey)
+{
+ *ptr = __LINE__;
+ dprintf1("disabling write access; after accessing the page, "
+ "to PKEY[%02d], doing write\n", pkey);
+ pkey_write_deny(pkey);
+ *ptr = __LINE__;
+ expected_pkey_faults(pkey);
+}
+
void test_write_of_write_disabled_region(int *ptr, u16 pkey)
{
dprintf1("disabling write access to PKEY[%02d], doing write\n", pkey);
pkey_write_deny(pkey);
*ptr = __LINE__;
- expected_pk_fault(pkey);
+ expected_pkey_faults(pkey);
}
void test_write_of_access_disabled_region(int *ptr, u16 pkey)
{
dprintf1("disabling access to PKEY[%02d], doing write\n", pkey);
pkey_access_deny(pkey);
*ptr = __LINE__;
- expected_pk_fault(pkey);
+ expected_pkey_faults(pkey);
+}
+
+void test_write_of_access_disabled_region_with_page_already_mapped(int *ptr,
+ u16 pkey)
+{
+ *ptr = __LINE__;
+ dprintf1("disabling access; after accessing the page, "
+ " to PKEY[%02d], doing write\n", pkey);
+ pkey_access_deny(pkey);
+ *ptr = __LINE__;
+ expected_pkey_faults(pkey);
}
+
void test_kernel_write_of_access_disabled_region(int *ptr, u16 pkey)
{
int ret;
@@ -1103,10 +1195,10 @@ void test_kernel_gup_write_to_write_disabled_region(int *ptr, u16 pkey)
void test_pkey_syscalls_on_non_allocated_pkey(int *ptr, u16 pkey)
{
int err;
- int i;
+ int i = get_start_key();

/* Note: 0 is the default pkey, so don't mess with it */
- for (i = 1; i < NR_PKEYS; i++) {
+ for (; i < NR_PKEYS; i++) {
if (pkey == i)
continue;

@@ -1126,7 +1218,7 @@ void test_pkey_syscalls_on_non_allocated_pkey(int *ptr, u16 pkey)
void test_pkey_syscalls_bad_args(int *ptr, u16 pkey)
{
int err;
- int bad_pkey = NR_PKEYS+99;
+ int bad_pkey = NR_PKEYS+pkey;

/* pass a known-invalid pkey in: */
err = sys_mprotect_pkey(ptr, PAGE_SIZE, PROT_READ, bad_pkey);
@@ -1136,21 +1228,24 @@ void test_pkey_syscalls_bad_args(int *ptr, u16 pkey)
/* Assumes that all pkeys other than 'pkey' are unallocated */
void test_pkey_alloc_exhaust(int *ptr, u16 pkey)
{
- int err;
+ int err = 0;
int allocated_pkeys[NR_PKEYS] = {0};
int nr_allocated_pkeys = 0;
int i;

for (i = 0; i < NR_PKEYS*2; i++) {
int new_pkey;
+
dprintf1("%s() alloc loop: %d\n", __func__, i);
new_pkey = alloc_pkey();
- dprintf4("%s()::%d, err: %d pkru: 0x%x shadow: 0x%x\n", __func__,
- __LINE__, err, __rdpkru(), shadow_pkru);
- rdpkru(); /* for shadow checking */
- dprintf2("%s() errno: %d ENOSPC: %d\n", __func__, errno, ENOSPC);
+ dprintf4("%s()::%d, err: %d pkey_reg: 0x%x shadow: 0x%x\n",
+ __func__, __LINE__, err, __rdpkey_reg(),
+ shadow_pkey_reg);
+ rdpkey_reg(); /* for shadow checking */
+ dprintf2("%s() errno: %d ENOSPC: %d\n", __func__, errno,
+ ENOSPC);
if ((new_pkey == -1) && (errno == ENOSPC)) {
- dprintf2("%s() failed to allocate pkey after %d tries\n",
+ dprintf2("%s() allocate failed pkey after %d tries\n",
__func__, nr_allocated_pkeys);
break;
}
@@ -1165,19 +1260,17 @@ void test_pkey_alloc_exhaust(int *ptr, u16 pkey)
* failure:
*/
pkey_assert(i < NR_PKEYS*2);
-
/*
- * There are 16 pkeys supported in hardware. One is taken
- * up for the default (0) and another can be taken up by
- * an execute-only mapping. Ensure that we can allocate
- * at least 14 (16-2).
+ * There are NR_PKEYS pkeys supported in hardware. NR_RESERVED_KEYS
+ * are reserved. One can be taken up by an execute-only mapping.
+ * Ensure that we can allocate at least the remaining.
*/
- pkey_assert(i >= NR_PKEYS-2);
+ pkey_assert(i >= (NR_PKEYS-NR_RESERVED_PKEYS-1));

for (i = 0; i < nr_allocated_pkeys; i++) {
err = sys_pkey_free(allocated_pkeys[i]);
pkey_assert(!err);
- rdpkru(); /* for shadow checking */
+ rdpkey_reg(); /* for shadow checking */
}
}

@@ -1221,10 +1314,10 @@ void test_ptrace_of_child(int *ptr, u16 pkey)
pkey_write_deny(pkey);

/* Write access, untested for now:
- ret = ptrace(PTRACE_POKEDATA, child_pid, peek_at, data);
- pkey_assert(ret != -1);
- dprintf1("poke at %p: %ld\n", peek_at, ret);
- */
+ * ret = ptrace(PTRACE_POKEDATA, child_pid, peek_at, data);
+ * pkey_assert(ret != -1);
+ * dprintf1("poke at %p: %ld\n", peek_at, ret);
+ */

/*
* Try to access the pkey-protected "ptr" via ptrace:
@@ -1234,7 +1327,7 @@ void test_ptrace_of_child(int *ptr, u16 pkey)
pkey_assert(ret != -1);
/* Now access from the current task, and expect an exception: */
peek_result = read_ptr(ptr);
- expected_pk_fault(pkey);
+ expected_pkey_faults(pkey);

/*
* Try to access the NON-pkey-protected "plain_ptr" via ptrace:
@@ -1281,7 +1374,7 @@ void test_executing_on_unreadable_memory(int *ptr, u16 pkey)
pkey_assert(!ret);
pkey_access_deny(pkey);

- dprintf2("pkru: %x\n", rdpkru());
+ dprintf2("pkey_reg: %x\n", rdpkey_reg());

/*
* Make sure this is an *instruction* fault
@@ -1291,7 +1384,7 @@ void test_executing_on_unreadable_memory(int *ptr, u16 pkey)
do_not_expect_pk_fault();
ptr_contents = read_ptr(p1);
dprintf2("ptr (%p) contents@%d: %x\n", p1, __LINE__, ptr_contents);
- expected_pk_fault(pkey);
+ expected_pkey_faults(pkey);
}

void test_mprotect_pkey_on_unsupported_cpu(int *ptr, u16 pkey)
@@ -1299,7 +1392,7 @@ void test_mprotect_pkey_on_unsupported_cpu(int *ptr, u16 pkey)
int size = PAGE_SIZE;
int sret;

- if (cpu_has_pku()) {
+ if (cpu_has_pkey()) {
dprintf1("SKIP: %s: no CPU support\n", __func__);
return;
}
@@ -1311,8 +1404,11 @@ void test_mprotect_pkey_on_unsupported_cpu(int *ptr, u16 pkey)
void (*pkey_tests[])(int *ptr, u16 pkey) = {
test_read_of_write_disabled_region,
test_read_of_access_disabled_region,
+ test_read_of_access_disabled_region_with_page_already_mapped,
test_write_of_write_disabled_region,
+ test_write_of_write_disabled_region_with_page_already_mapped,
test_write_of_access_disabled_region,
+ test_write_of_access_disabled_region_with_page_already_mapped,
test_kernel_write_of_access_disabled_region,
test_kernel_write_of_write_disabled_region,
test_kernel_gup_of_access_disabled_region,
@@ -1331,7 +1427,7 @@ void run_tests_once(void)

for (test_nr = 0; test_nr < ARRAY_SIZE(pkey_tests); test_nr++) {
int pkey;
- int orig_pkru_faults = pkru_faults;
+ int orig_pkey_faults = pkey_faults;

dprintf1("======================\n");
dprintf1("test %d preparing...\n", test_nr);
@@ -1346,45 +1442,42 @@ void run_tests_once(void)
free_pkey_malloc(ptr);
sys_pkey_free(pkey);

- dprintf1("pkru_faults: %d\n", pkru_faults);
- dprintf1("orig_pkru_faults: %d\n", orig_pkru_faults);
+ dprintf1("pkey_faults: %d\n", pkey_faults);
+ dprintf1("orig_pkey_faults: %d\n", orig_pkey_faults);

tracing_off();
close_test_fds();

- printf("test %2d PASSED (iteration %d)\n", test_nr, iteration_nr);
+ printf("test %2d PASSED (iteration %d)\n",
+ test_nr, iteration_nr);
dprintf1("======================\n\n");
}
iteration_nr++;
}

-void pkey_setup_shadow(void)
-{
- shadow_pkru = __rdpkru();
-}
-
int main(void)
{
int nr_iterations = 22;

setup_handlers();

- printf("has pku: %d\n", cpu_has_pku());
+ printf("has pkey support: %d\n", cpu_has_pkey());

- if (!cpu_has_pku()) {
+ if (!cpu_has_pkey()) {
int size = PAGE_SIZE;
int *ptr;

printf("running PKEY tests for unsupported CPU/OS\n");

- ptr = mmap(NULL, size, PROT_NONE, MAP_ANONYMOUS|MAP_PRIVATE, -1, 0);
+ ptr = mmap(NULL, size, PROT_NONE,
+ MAP_ANONYMOUS|MAP_PRIVATE, -1, 0);
assert(ptr != (void *)-1);
test_mprotect_pkey_on_unsupported_cpu(ptr, 1);
exit(0);
}

pkey_setup_shadow();
- printf("startup pkru: %x\n", rdpkru());
+ printf("startup pkey_reg: %lx\n", rdpkey_reg());
setup_hugetlbfs();

while (nr_iterations-- > 0)
--
1.8.3.1

2017-06-27 10:13:30

by Ram Pai

Subject: [RFC v4 17/17] procfs: display the protection-key number associated with a vma

Display the pkey number associated with the vma in smaps of a task.
The key will be seen as below:

VmFlags: rd wr mr mw me dw ac key=0

Signed-off-by: Ram Pai <[email protected]>
---
Documentation/filesystems/proc.txt | 3 ++-
fs/proc/task_mmu.c | 22 +++++++++++-----------
2 files changed, 13 insertions(+), 12 deletions(-)

diff --git a/Documentation/filesystems/proc.txt b/Documentation/filesystems/proc.txt
index 4cddbce..a8c74aa 100644
--- a/Documentation/filesystems/proc.txt
+++ b/Documentation/filesystems/proc.txt
@@ -423,7 +423,7 @@ SwapPss: 0 kB
KernelPageSize: 4 kB
MMUPageSize: 4 kB
Locked: 0 kB
-VmFlags: rd ex mr mw me dw
+VmFlags: rd ex mr mw me dw key=<num>

the first of these lines shows the same information as is displayed for the
mapping in /proc/PID/maps. The remaining lines show the size of the mapping
@@ -491,6 +491,7 @@ manner. The codes are the following:
hg - huge page advise flag
nh - no-huge page advise flag
mg - mergable advise flag
+ key=<num> - the memory protection key number

Note that there is no guarantee that every flag and associated mnemonic will
be present in all further kernel releases. Things get changed, the flags may
diff --git a/fs/proc/task_mmu.c b/fs/proc/task_mmu.c
index 2ddc298..d2eb096 100644
--- a/fs/proc/task_mmu.c
+++ b/fs/proc/task_mmu.c
@@ -1,4 +1,6 @@
#include <linux/mm.h>
+#include <linux/pkeys.h>
+#include <linux/huge_mm.h>
#include <linux/vmacache.h>
#include <linux/hugetlb.h>
#include <linux/huge_mm.h>
@@ -666,22 +668,20 @@ static void show_smap_vma_flags(struct seq_file *m, struct vm_area_struct *vma)
[ilog2(VM_MERGEABLE)] = "mg",
[ilog2(VM_UFFD_MISSING)]= "um",
[ilog2(VM_UFFD_WP)] = "uw",
-#ifdef CONFIG_ARCH_HAS_PKEYS
- /* These come out via ProtectionKey: */
- [ilog2(VM_PKEY_BIT0)] = "",
- [ilog2(VM_PKEY_BIT1)] = "",
- [ilog2(VM_PKEY_BIT2)] = "",
- [ilog2(VM_PKEY_BIT3)] = "",
-#endif /* CONFIG_ARCH_HAS_PKEYS */
-#ifdef CONFIG_PPC64_MEMORY_PROTECTION_KEYS
- /* Additional bit in ProtectionKey: */
- [ilog2(VM_PKEY_BIT4)] = "",
-#endif
};
size_t i;

seq_puts(m, "VmFlags: ");
for (i = 0; i < BITS_PER_LONG; i++) {
+#ifdef CONFIG_ARCH_HAS_PKEYS
+ if (i == ilog2(VM_PKEY_BIT0)) {
+ int keyvalue = vma_pkey(vma);
+
+ i += ilog2(arch_max_pkey())-1;
+ seq_printf(m, "key=%d ", keyvalue);
+ continue;
+ }
+#endif /* CONFIG_ARCH_HAS_PKEYS */
if (!mnemonics[i][0])
continue;
if (vma->vm_flags & (1UL << i)) {
--
1.8.3.1

2017-06-27 10:14:19

by Ram Pai

Subject: [RFC v4 15/17] Documentation: Move protecton key documentation to arch neutral directory

Since PowerPC and Intel both support memory protection keys, moving
the documenation to arch-neutral directory.

Signed-off-by: Ram Pai <[email protected]>
---
Documentation/vm/protection-keys.txt | 85 +++++++++++++++++++++++++++++++++++
Documentation/x86/protection-keys.txt | 85 -----------------------------------
2 files changed, 85 insertions(+), 85 deletions(-)
create mode 100644 Documentation/vm/protection-keys.txt
delete mode 100644 Documentation/x86/protection-keys.txt

diff --git a/Documentation/vm/protection-keys.txt b/Documentation/vm/protection-keys.txt
new file mode 100644
index 0000000..b643045
--- /dev/null
+++ b/Documentation/vm/protection-keys.txt
@@ -0,0 +1,85 @@
+Memory Protection Keys for Userspace (PKU aka PKEYs) is a CPU feature
+which will be found on future Intel CPUs.
+
+Memory Protection Keys provides a mechanism for enforcing page-based
+protections, but without requiring modification of the page tables
+when an application changes protection domains. It works by
+dedicating 4 previously ignored bits in each page table entry to a
+"protection key", giving 16 possible keys.
+
+There is also a new user-accessible register (PKRU) with two separate
+bits (Access Disable and Write Disable) for each key. Being a CPU
+register, PKRU is inherently thread-local, potentially giving each
+thread a different set of protections from every other thread.
+
+There are two new instructions (RDPKRU/WRPKRU) for reading and writing
+to the new register. The feature is only available in 64-bit mode,
+even though there is theoretically space in the PAE PTEs. These
+permissions are enforced on data access only and have no effect on
+instruction fetches.
+
+=========================== Syscalls ===========================
+
+There are 3 system calls which directly interact with pkeys:
+
+ int pkey_alloc(unsigned long flags, unsigned long init_access_rights)
+ int pkey_free(int pkey);
+ int pkey_mprotect(unsigned long start, size_t len,
+ unsigned long prot, int pkey);
+
+Before a pkey can be used, it must first be allocated with
+pkey_alloc(). An application calls the WRPKRU instruction
+directly in order to change access permissions to memory covered
+with a key. In this example WRPKRU is wrapped by a C function
+called pkey_set().
+
+ int real_prot = PROT_READ|PROT_WRITE;
+ pkey = pkey_alloc(0, PKEY_DENY_WRITE);
+ ptr = mmap(NULL, PAGE_SIZE, PROT_NONE, MAP_ANONYMOUS|MAP_PRIVATE, -1, 0);
+ ret = pkey_mprotect(ptr, PAGE_SIZE, real_prot, pkey);
+ ... application runs here
+
+Now, if the application needs to update the data at 'ptr', it can
+gain access, do the update, then remove its write access:
+
+ pkey_set(pkey, 0); // clear PKEY_DENY_WRITE
+ *ptr = foo; // assign something
+ pkey_set(pkey, PKEY_DENY_WRITE); // set PKEY_DENY_WRITE again
+
+Now when it frees the memory, it will also free the pkey since it
+is no longer in use:
+
+ munmap(ptr, PAGE_SIZE);
+ pkey_free(pkey);
+
+(Note: pkey_set() is a wrapper for the RDPKRU and WRPKRU instructions.
+ An example implementation can be found in
+ tools/testing/selftests/x86/protection_keys.c)
+
+=========================== Behavior ===========================
+
+The kernel attempts to make protection keys consistent with the
+behavior of a plain mprotect(). For instance if you do this:
+
+ mprotect(ptr, size, PROT_NONE);
+ something(ptr);
+
+you can expect the same effects with protection keys when doing this:
+
+ pkey = pkey_alloc(0, PKEY_DISABLE_WRITE | PKEY_DISABLE_READ);
+ pkey_mprotect(ptr, size, PROT_READ|PROT_WRITE, pkey);
+ something(ptr);
+
+That should be true whether something() is a direct access to 'ptr'
+like:
+
+ *ptr = foo;
+
+or when the kernel does the access on the application's behalf like
+with a read():
+
+ read(fd, ptr, 1);
+
+The kernel will send a SIGSEGV in both cases, but si_code will be set
+to SEGV_PKERR when violating protection keys versus SEGV_ACCERR when
+the plain mprotect() permissions are violated.
diff --git a/Documentation/x86/protection-keys.txt b/Documentation/x86/protection-keys.txt
deleted file mode 100644
index b643045..0000000
--- a/Documentation/x86/protection-keys.txt
+++ /dev/null
@@ -1,85 +0,0 @@
-Memory Protection Keys for Userspace (PKU aka PKEYs) is a CPU feature
-which will be found on future Intel CPUs.
-
-Memory Protection Keys provides a mechanism for enforcing page-based
-protections, but without requiring modification of the page tables
-when an application changes protection domains. It works by
-dedicating 4 previously ignored bits in each page table entry to a
-"protection key", giving 16 possible keys.
-
-There is also a new user-accessible register (PKRU) with two separate
-bits (Access Disable and Write Disable) for each key. Being a CPU
-register, PKRU is inherently thread-local, potentially giving each
-thread a different set of protections from every other thread.
-
-There are two new instructions (RDPKRU/WRPKRU) for reading and writing
-to the new register. The feature is only available in 64-bit mode,
-even though there is theoretically space in the PAE PTEs. These
-permissions are enforced on data access only and have no effect on
-instruction fetches.
-
-=========================== Syscalls ===========================
-
-There are 3 system calls which directly interact with pkeys:
-
- int pkey_alloc(unsigned long flags, unsigned long init_access_rights)
- int pkey_free(int pkey);
- int pkey_mprotect(unsigned long start, size_t len,
- unsigned long prot, int pkey);
-
-Before a pkey can be used, it must first be allocated with
-pkey_alloc(). An application calls the WRPKRU instruction
-directly in order to change access permissions to memory covered
-with a key. In this example WRPKRU is wrapped by a C function
-called pkey_set().
-
- int real_prot = PROT_READ|PROT_WRITE;
- pkey = pkey_alloc(0, PKEY_DENY_WRITE);
- ptr = mmap(NULL, PAGE_SIZE, PROT_NONE, MAP_ANONYMOUS|MAP_PRIVATE, -1, 0);
- ret = pkey_mprotect(ptr, PAGE_SIZE, real_prot, pkey);
- ... application runs here
-
-Now, if the application needs to update the data at 'ptr', it can
-gain access, do the update, then remove its write access:
-
- pkey_set(pkey, 0); // clear PKEY_DENY_WRITE
- *ptr = foo; // assign something
- pkey_set(pkey, PKEY_DENY_WRITE); // set PKEY_DENY_WRITE again
-
-Now when it frees the memory, it will also free the pkey since it
-is no longer in use:
-
- munmap(ptr, PAGE_SIZE);
- pkey_free(pkey);
-
-(Note: pkey_set() is a wrapper for the RDPKRU and WRPKRU instructions.
- An example implementation can be found in
- tools/testing/selftests/x86/protection_keys.c)
-
-=========================== Behavior ===========================
-
-The kernel attempts to make protection keys consistent with the
-behavior of a plain mprotect(). For instance if you do this:
-
- mprotect(ptr, size, PROT_NONE);
- something(ptr);
-
-you can expect the same effects with protection keys when doing this:
-
- pkey = pkey_alloc(0, PKEY_DISABLE_WRITE | PKEY_DISABLE_READ);
- pkey_mprotect(ptr, size, PROT_READ|PROT_WRITE, pkey);
- something(ptr);
-
-That should be true whether something() is a direct access to 'ptr'
-like:
-
- *ptr = foo;
-
-or when the kernel does the access on the application's behalf like
-with a read():
-
- read(fd, ptr, 1);
-
-The kernel will send a SIGSEGV in both cases, but si_code will be set
-to SEGV_PKERR when violating protection keys versus SEGV_ACCERR when
-the plain mprotect() permissions are violated.
--
1.8.3.1

2017-06-27 10:14:53

by Ram Pai

Subject: [RFC v4 08/17] powerpc: Program HPTE key protection bits

Map the PTE protection key bits to the HPTE key protection bits,
while creating HPTE entries.

Signed-off-by: Ram Pai <[email protected]>
---
Makefile | 2 +-
arch/powerpc/include/asm/book3s/64/mmu-hash.h | 5 +++++
arch/powerpc/include/asm/pkeys.h | 9 +++++++++
arch/powerpc/mm/hash_utils_64.c | 4 ++++
4 files changed, 19 insertions(+), 1 deletion(-)

diff --git a/Makefile b/Makefile
index 470bd4d..141ea4e 100644
--- a/Makefile
+++ b/Makefile
@@ -1,7 +1,7 @@
VERSION = 4
PATCHLEVEL = 12
SUBLEVEL = 0
-EXTRAVERSION = -rc3
+EXTRAVERSION = -rc3-64k
NAME = Fearless Coyote

# *DOCUMENTATION*
diff --git a/arch/powerpc/include/asm/book3s/64/mmu-hash.h b/arch/powerpc/include/asm/book3s/64/mmu-hash.h
index aa3c299..721a4c3 100644
--- a/arch/powerpc/include/asm/book3s/64/mmu-hash.h
+++ b/arch/powerpc/include/asm/book3s/64/mmu-hash.h
@@ -90,6 +90,8 @@
#define HPTE_R_PP0 ASM_CONST(0x8000000000000000)
#define HPTE_R_TS ASM_CONST(0x4000000000000000)
#define HPTE_R_KEY_HI ASM_CONST(0x3000000000000000)
+#define HPTE_R_KEY_BIT0 ASM_CONST(0x2000000000000000)
+#define HPTE_R_KEY_BIT1 ASM_CONST(0x1000000000000000)
#define HPTE_R_RPN_SHIFT 12
#define HPTE_R_RPN ASM_CONST(0x0ffffffffffff000)
#define HPTE_R_RPN_3_0 ASM_CONST(0x01fffffffffff000)
@@ -104,6 +106,9 @@
#define HPTE_R_C ASM_CONST(0x0000000000000080)
#define HPTE_R_R ASM_CONST(0x0000000000000100)
#define HPTE_R_KEY_LO ASM_CONST(0x0000000000000e00)
+#define HPTE_R_KEY_BIT2 ASM_CONST(0x0000000000000800)
+#define HPTE_R_KEY_BIT3 ASM_CONST(0x0000000000000400)
+#define HPTE_R_KEY_BIT4 ASM_CONST(0x0000000000000200)

#define HPTE_V_1TB_SEG ASM_CONST(0x4000000000000000)
#define HPTE_V_VRMA_MASK ASM_CONST(0x4001ffffff000000)
diff --git a/arch/powerpc/include/asm/pkeys.h b/arch/powerpc/include/asm/pkeys.h
index 41bf5d4..ef1c601 100644
--- a/arch/powerpc/include/asm/pkeys.h
+++ b/arch/powerpc/include/asm/pkeys.h
@@ -23,6 +23,15 @@ static inline unsigned long pkey_to_vmflag_bits(int pkey)
((pkey & 0x10UL) ? VM_PKEY_BIT4 : 0x0UL));
}

+static inline unsigned long pkey_to_hpte_pkey_bits(int pkey)
+{
+ return (((pkey & 0x10) ? HPTE_R_KEY_BIT0 : 0x0UL) |
+ ((pkey & 0x8) ? HPTE_R_KEY_BIT1 : 0x0UL) |
+ ((pkey & 0x4) ? HPTE_R_KEY_BIT2 : 0x0UL) |
+ ((pkey & 0x2) ? HPTE_R_KEY_BIT3 : 0x0UL) |
+ ((pkey & 0x1) ? HPTE_R_KEY_BIT4 : 0x0UL));
+}
+
/*
* Bits are in BE format.
* NOTE: key 31, 1, 0 are not used.
diff --git a/arch/powerpc/mm/hash_utils_64.c b/arch/powerpc/mm/hash_utils_64.c
index 2254ff0..7e67dea 100644
--- a/arch/powerpc/mm/hash_utils_64.c
+++ b/arch/powerpc/mm/hash_utils_64.c
@@ -231,6 +231,10 @@ unsigned long htab_convert_pte_flags(unsigned long pteflags, int pkey)
*/
rflags |= HPTE_R_M;

+#ifdef CONFIG_PPC64_MEMORY_PROTECTION_KEYS
+ rflags |= pkey_to_hpte_pkey_bits(pkey);
+#endif
+
return rflags;
}

--
1.8.3.1

2017-06-27 10:15:01

by Ram Pai

Subject: [RFC v4 10/17] powerpc: Macro the mask used for checking DSI exception

Replace the magic number used to check for DSI exception
with a meaningful value.

Signed-off-by: Ram Pai <[email protected]>
---
arch/powerpc/include/asm/reg.h | 7 ++++++-
arch/powerpc/kernel/exceptions-64s.S | 2 +-
2 files changed, 7 insertions(+), 2 deletions(-)

diff --git a/arch/powerpc/include/asm/reg.h b/arch/powerpc/include/asm/reg.h
index 7e50e47..ba110dd 100644
--- a/arch/powerpc/include/asm/reg.h
+++ b/arch/powerpc/include/asm/reg.h
@@ -272,16 +272,21 @@
#define SPRN_DAR 0x013 /* Data Address Register */
#define SPRN_DBCR 0x136 /* e300 Data Breakpoint Control Reg */
#define SPRN_DSISR 0x012 /* Data Storage Interrupt Status Register */
+#define DSISR_BIT32 0x80000000 /* not defined */
#define DSISR_NOHPTE 0x40000000 /* no translation found */
+#define DSISR_PAGEATTR_CONFLT 0x20000000 /* page attribute conflict */
+#define DSISR_BIT35 0x10000000 /* not defined */
#define DSISR_PROTFAULT 0x08000000 /* protection fault */
#define DSISR_BADACCESS 0x04000000 /* bad access to CI or G */
#define DSISR_ISSTORE 0x02000000 /* access was a store */
#define DSISR_DABRMATCH 0x00400000 /* hit data breakpoint */
-#define DSISR_NOSEGMENT 0x00200000 /* SLB miss */
#define DSISR_KEYFAULT 0x00200000 /* Key fault */
+#define DSISR_BIT43 0x00100000 /* not defined */
#define DSISR_UNSUPP_MMU 0x00080000 /* Unsupported MMU config */
#define DSISR_SET_RC 0x00040000 /* Failed setting of R/C bits */
#define DSISR_PGDIRFAULT 0x00020000 /* Fault on page directory */
+#define DSISR_PAGE_FAULT_MASK (DSISR_BIT32 | DSISR_PAGEATTR_CONFLT | \
+ DSISR_BADACCESS | DSISR_BIT43)
#define SPRN_TBRL 0x10C /* Time Base Read Lower Register (user, R/O) */
#define SPRN_TBRU 0x10D /* Time Base Read Upper Register (user, R/O) */
#define SPRN_CIR 0x11B /* Chip Information Register (hyper, R/0) */
diff --git a/arch/powerpc/kernel/exceptions-64s.S b/arch/powerpc/kernel/exceptions-64s.S
index ae418b8..3fd0528 100644
--- a/arch/powerpc/kernel/exceptions-64s.S
+++ b/arch/powerpc/kernel/exceptions-64s.S
@@ -1411,7 +1411,7 @@ USE_TEXT_SECTION()
.balign IFETCH_ALIGN_BYTES
do_hash_page:
#ifdef CONFIG_PPC_STD_MMU_64
- andis. r0,r4,0xa410 /* weird error? */
+ andis. r0,r4,DSISR_PAGE_FAULT_MASK@h
bne- handle_page_fault /* if not, try to insert a HPTE */
andis. r0,r4,DSISR_DABRMATCH@h
bne- handle_dabr_fault
--
1.8.3.1

2017-06-27 10:15:12

by Ram Pai

Subject: [RFC v4 12/17] powerpc: Deliver SEGV signal on pkey violation

The value of the AMR register at the time of exception
is made available in gp_regs[PT_AMR] of the siginfo.

The value of the pkey, whose protection got violated,
is made available in si_pkey field of the siginfo structure.

Signed-off-by: Ram Pai <[email protected]>
---
arch/powerpc/include/asm/paca.h | 1 +
arch/powerpc/include/uapi/asm/ptrace.h | 3 ++-
arch/powerpc/kernel/asm-offsets.c | 5 ++++
arch/powerpc/kernel/exceptions-64s.S | 16 +++++++++--
arch/powerpc/kernel/signal_32.c | 5 ++++
arch/powerpc/kernel/signal_64.c | 4 +++
arch/powerpc/kernel/traps.c | 49 ++++++++++++++++++++++++++++++++++
arch/powerpc/mm/fault.c | 2 ++
8 files changed, 82 insertions(+), 3 deletions(-)

diff --git a/arch/powerpc/include/asm/paca.h b/arch/powerpc/include/asm/paca.h
index 1c09f8f..a41afd3 100644
--- a/arch/powerpc/include/asm/paca.h
+++ b/arch/powerpc/include/asm/paca.h
@@ -92,6 +92,7 @@ struct paca_struct {
struct dtl_entry *dispatch_log_end;
#endif /* CONFIG_PPC_STD_MMU_64 */
u64 dscr_default; /* per-CPU default DSCR */
+ u64 paca_amr; /* value of amr at exception */

#ifdef CONFIG_PPC_STD_MMU_64
/*
diff --git a/arch/powerpc/include/uapi/asm/ptrace.h b/arch/powerpc/include/uapi/asm/ptrace.h
index 8036b38..7ec2428 100644
--- a/arch/powerpc/include/uapi/asm/ptrace.h
+++ b/arch/powerpc/include/uapi/asm/ptrace.h
@@ -108,8 +108,9 @@ struct pt_regs {
#define PT_DAR 41
#define PT_DSISR 42
#define PT_RESULT 43
-#define PT_DSCR 44
#define PT_REGS_COUNT 44
+#define PT_DSCR 44
+#define PT_AMR 45

#define PT_FPR0 48 /* each FP reg occupies 2 slots in this space */

diff --git a/arch/powerpc/kernel/asm-offsets.c b/arch/powerpc/kernel/asm-offsets.c
index 709e234..17f5d8a 100644
--- a/arch/powerpc/kernel/asm-offsets.c
+++ b/arch/powerpc/kernel/asm-offsets.c
@@ -241,6 +241,11 @@ int main(void)
OFFSET(PACAHWCPUID, paca_struct, hw_cpu_id);
OFFSET(PACAKEXECSTATE, paca_struct, kexec_state);
OFFSET(PACA_DSCR_DEFAULT, paca_struct, dscr_default);
+
+#ifdef CONFIG_PPC64_MEMORY_PROTECTION_KEYS
+ OFFSET(PACA_AMR, paca_struct, paca_amr);
+#endif /* CONFIG_PPC64_MEMORY_PROTECTION_KEYS */
+
OFFSET(ACCOUNT_STARTTIME, paca_struct, accounting.starttime);
OFFSET(ACCOUNT_STARTTIME_USER, paca_struct, accounting.starttime_user);
OFFSET(ACCOUNT_USER_TIME, paca_struct, accounting.utime);
diff --git a/arch/powerpc/kernel/exceptions-64s.S b/arch/powerpc/kernel/exceptions-64s.S
index 3fd0528..a4de1b4 100644
--- a/arch/powerpc/kernel/exceptions-64s.S
+++ b/arch/powerpc/kernel/exceptions-64s.S
@@ -493,9 +493,15 @@ EXC_COMMON_BEGIN(data_access_common)
ld r12,_MSR(r1)
ld r3,PACA_EXGEN+EX_DAR(r13)
lwz r4,PACA_EXGEN+EX_DSISR(r13)
- li r5,0x300
std r3,_DAR(r1)
std r4,_DSISR(r1)
+#ifdef CONFIG_PPC64_MEMORY_PROTECTION_KEYS
+ andis. r0,r4,DSISR_KEYFAULT@h /* save AMR only if its a key fault */
+ beq+ 1f
+ mfspr r5,SPRN_AMR
+ std r5,PACA_AMR(r13)
+#endif /* CONFIG_PPC64_MEMORY_PROTECTION_KEYS */
+1: li r5,0x300
BEGIN_MMU_FTR_SECTION
b do_hash_page /* Try to handle as hpte fault */
MMU_FTR_SECTION_ELSE
@@ -561,9 +567,15 @@ EXC_COMMON_BEGIN(instruction_access_common)
ld r12,_MSR(r1)
ld r3,_NIP(r1)
andis. r4,r12,0x5820
- li r5,0x400
std r3,_DAR(r1)
std r4,_DSISR(r1)
+#ifdef CONFIG_PPC64_MEMORY_PROTECTION_KEYS
+ andis. r0,r4,DSISR_KEYFAULT@h /* save AMR only if its a key fault */
+ beq+ 1f
+ mfspr r5,SPRN_AMR
+ std r5,PACA_AMR(r13)
+#endif /* CONFIG_PPC64_MEMORY_PROTECTION_KEYS */
+1: li r5,0x400
BEGIN_MMU_FTR_SECTION
b do_hash_page /* Try to handle as hpte fault */
MMU_FTR_SECTION_ELSE
diff --git a/arch/powerpc/kernel/signal_32.c b/arch/powerpc/kernel/signal_32.c
index 97bb138..9c4a7f3 100644
--- a/arch/powerpc/kernel/signal_32.c
+++ b/arch/powerpc/kernel/signal_32.c
@@ -500,6 +500,11 @@ static int save_user_regs(struct pt_regs *regs, struct mcontext __user *frame,
(unsigned long) &frame->tramp[2]);
}

+#ifdef CONFIG_PPC64_MEMORY_PROTECTION_KEYS
+ if (__put_user(get_paca()->paca_amr, &frame->mc_gregs[PT_AMR]))
+ return 1;
+#endif /* CONFIG_PPC64_MEMORY_PROTECTION_KEYS */
+
return 0;
}

diff --git a/arch/powerpc/kernel/signal_64.c b/arch/powerpc/kernel/signal_64.c
index c83c115..86a4262 100644
--- a/arch/powerpc/kernel/signal_64.c
+++ b/arch/powerpc/kernel/signal_64.c
@@ -174,6 +174,10 @@ static long setup_sigcontext(struct sigcontext __user *sc,
if (set != NULL)
err |= __put_user(set->sig[0], &sc->oldmask);

+#ifdef CONFIG_PPC64_MEMORY_PROTECTION_KEYS
+ err |= __put_user(get_paca()->paca_amr, &sc->gp_regs[PT_AMR]);
+#endif /* CONFIG_PPC64_MEMORY_PROTECTION_KEYS */
+
return err;
}

diff --git a/arch/powerpc/kernel/traps.c b/arch/powerpc/kernel/traps.c
index d4e545d..cc4bde8b 100644
--- a/arch/powerpc/kernel/traps.c
+++ b/arch/powerpc/kernel/traps.c
@@ -20,6 +20,7 @@
#include <linux/sched/debug.h>
#include <linux/kernel.h>
#include <linux/mm.h>
+#include <linux/pkeys.h>
#include <linux/stddef.h>
#include <linux/unistd.h>
#include <linux/ptrace.h>
@@ -247,6 +248,49 @@ void user_single_step_siginfo(struct task_struct *tsk,
info->si_addr = (void __user *)regs->nip;
}

+#ifdef CONFIG_PPC64_MEMORY_PROTECTION_KEYS
+static void fill_sig_info_pkey(int si_code, siginfo_t *info, unsigned long addr)
+{
+ struct vm_area_struct *vma;
+
+ /* Fault not from Protection Keys: nothing to do */
+ if (si_code != SEGV_PKUERR)
+ return;
+
+ down_read(&current->mm->mmap_sem);
+ /*
+ * we could be racing with pkey_mprotect().
+ * If pkey_mprotect() wins the key value could
+ * get modified...xxx
+ */
+ vma = find_vma(current->mm, addr);
+ up_read(&current->mm->mmap_sem);
+
+ /*
+ * force_sig_info_fault() is called from a number of
+ * contexts, some of which have a VMA and some of which
+ * do not. The Pkey-fault handing happens after we have a
+ * valid VMA, so we should never reach this without a
+ * valid VMA.
+ */
+ if (!vma) {
+ WARN_ONCE(1, "Pkey fault with no VMA passed in");
+ info->si_pkey = 0;
+ return;
+ }
+
+ /*
+ * We could report the incorrect key because of the reason
+ * explained above.
+ *
+ * si_pkey should be thought off as a strong hint, but not
+ * an absolutely guarantee because of the race explained
+ * above.
+ */
+ info->si_pkey = vma_pkey(vma);
+}
+#endif /* CONFIG_PPC64_MEMORY_PROTECTION_KEYS */
+
void _exception(int signr, struct pt_regs *regs, int code, unsigned long addr)
{
siginfo_t info;
@@ -274,6 +318,11 @@ void _exception(int signr, struct pt_regs *regs, int code, unsigned long addr)
info.si_signo = signr;
info.si_code = code;
info.si_addr = (void __user *) addr;
+
+#ifdef CONFIG_PPC64_MEMORY_PROTECTION_KEYS
+ fill_sig_info_pkey(code, &info, addr);
+#endif /* CONFIG_PPC64_MEMORY_PROTECTION_KEYS */
+
force_sig_info(signr, &info, current);
}

diff --git a/arch/powerpc/mm/fault.c b/arch/powerpc/mm/fault.c
index 3d71984..0780a53 100644
--- a/arch/powerpc/mm/fault.c
+++ b/arch/powerpc/mm/fault.c
@@ -451,6 +451,8 @@ int do_page_fault(struct pt_regs *regs, unsigned long address,
#ifdef CONFIG_PPC64_MEMORY_PROTECTION_KEYS
if (!arch_vma_access_permitted(vma, flags & FAULT_FLAG_WRITE,
is_exec, 0)) {
+ /* our caller may not have saved the amr. Lets save it */
+ get_paca()->paca_amr = read_amr();
code = SEGV_PKUERR;
goto bad_area;
}
--
1.8.3.1

2017-06-27 10:12:36

by Ram Pai

Subject: [RFC v4 02/17] mm: ability to disable execute permission on a key at creation

Currently sys_pkey_create() provides the ability to disable read
and write permission on the key, at creation. powerpc has the
hardware support to disable execute on a pkey as well.This patch
enhances the interface to let disable execute at key creation
time. x86 does not allow this. Hence the next patch will add
ability in x86 to return error if PKEY_DISABLE_EXECUTE is
specified.

Signed-off-by: Ram Pai <[email protected]>
---
include/uapi/asm-generic/mman-common.h | 4 +++-
1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/include/uapi/asm-generic/mman-common.h b/include/uapi/asm-generic/mman-common.h
index 8c27db0..bf4fa07 100644
--- a/include/uapi/asm-generic/mman-common.h
+++ b/include/uapi/asm-generic/mman-common.h
@@ -74,7 +74,9 @@

#define PKEY_DISABLE_ACCESS 0x1
#define PKEY_DISABLE_WRITE 0x2
+#define PKEY_DISABLE_EXECUTE 0x4
#define PKEY_ACCESS_MASK (PKEY_DISABLE_ACCESS |\
- PKEY_DISABLE_WRITE)
+ PKEY_DISABLE_WRITE |\
+ PKEY_DISABLE_EXECUTE)

#endif /* __ASM_GENERIC_MMAN_COMMON_H */
--
1.8.3.1

2017-06-27 10:16:57

by Ram Pai

Subject: [RFC v4 09/17] powerpc: call the hash functions with the correct pkey value

Pass the correct protection key value to the hash functions on
page fault.

Signed-off-by: Ram Pai <[email protected]>
---
arch/powerpc/include/asm/pkeys.h | 11 +++++++++++
arch/powerpc/mm/hash_utils_64.c | 4 ++++
arch/powerpc/mm/mem.c | 6 ++++++
3 files changed, 21 insertions(+)

diff --git a/arch/powerpc/include/asm/pkeys.h b/arch/powerpc/include/asm/pkeys.h
index ef1c601..1370b3f 100644
--- a/arch/powerpc/include/asm/pkeys.h
+++ b/arch/powerpc/include/asm/pkeys.h
@@ -74,6 +74,17 @@ static inline bool mm_pkey_is_allocated(struct mm_struct *mm, int pkey)
}

/*
+ * return the protection key of the vma corresponding to the
+ * given effective address @ea.
+ */
+static inline int mm_pkey(struct mm_struct *mm, unsigned long ea)
+{
+ struct vm_area_struct *vma = find_vma(mm, ea);
+ int pkey = vma ? vma_pkey(vma) : 0;
+ return pkey;
+}
+
+/*
* Returns a positive, 5-bit key on success, or -1 on failure.
*/
static inline int mm_pkey_alloc(struct mm_struct *mm)
diff --git a/arch/powerpc/mm/hash_utils_64.c b/arch/powerpc/mm/hash_utils_64.c
index 7e67dea..403f75d 100644
--- a/arch/powerpc/mm/hash_utils_64.c
+++ b/arch/powerpc/mm/hash_utils_64.c
@@ -1319,6 +1319,10 @@ int hash_page_mm(struct mm_struct *mm, unsigned long ea,
goto bail;
}

+#ifdef CONFIG_PPC64_MEMORY_PROTECTION_KEYS
+ pkey = mm_pkey(mm, ea);
+#endif /* CONFIG_PPC64_MEMORY_PROTECTION_KEYS */
+
if (hugeshift) {
if (is_thp)
rc = __hash_page_thp(ea, access, vsid, (pmd_t *)ptep,
diff --git a/arch/powerpc/mm/mem.c b/arch/powerpc/mm/mem.c
index ec890d3..0fcaa48 100644
--- a/arch/powerpc/mm/mem.c
+++ b/arch/powerpc/mm/mem.c
@@ -541,8 +541,14 @@ void update_mmu_cache(struct vm_area_struct *vma, unsigned long address,
return;
}

+#ifdef CONFIG_PPC64_MEMORY_PROTECTION_KEYS
+ hash_preload_pkey(vma->vm_mm, address, access, trap, vma_pkey(vma));
+#else
hash_preload(vma->vm_mm, address, access, trap);
+#endif /* CONFIG_PPC64_MEMORY_PROTECTION_KEYS */
+
#endif /* CONFIG_PPC_STD_MMU */
+
#if (defined(CONFIG_PPC_BOOK3E_64) || defined(CONFIG_PPC_FSL_BOOK3E)) \
&& defined(CONFIG_HUGETLB_PAGE)
if (is_vm_hugetlb_page(vma))
--
1.8.3.1

2017-06-27 10:17:25

by Ram Pai

Subject: [RFC v4 04/17] powerpc: Implement sys_pkey_alloc and sys_pkey_free system call

Sys_pkey_alloc() allocates and returns available pkey
Sys_pkey_free() frees up the pkey.

Total 32 keys are supported on powerpc. However pkey 0,1 and 31
are reserved. So effectively we have 29 pkeys.

Each key can be initialized to disable read, write and execute
permissions. On powerpc a key can be initialize to disable execute.

Signed-off-by: Ram Pai <[email protected]>
---
arch/powerpc/Kconfig | 15 ++++
arch/powerpc/include/asm/book3s/64/mmu.h | 10 +++
arch/powerpc/include/asm/book3s/64/pgtable.h | 62 ++++++++++++++
arch/powerpc/include/asm/pkeys.h | 124 +++++++++++++++++++++++++++
arch/powerpc/include/asm/systbl.h | 2 +
arch/powerpc/include/asm/unistd.h | 4 +-
arch/powerpc/include/uapi/asm/unistd.h | 2 +
arch/powerpc/mm/Makefile | 1 +
arch/powerpc/mm/mmu_context_book3s64.c | 5 ++
arch/powerpc/mm/pkeys.c | 88 +++++++++++++++++++
10 files changed, 310 insertions(+), 3 deletions(-)
create mode 100644 arch/powerpc/include/asm/pkeys.h
create mode 100644 arch/powerpc/mm/pkeys.c

diff --git a/arch/powerpc/Kconfig b/arch/powerpc/Kconfig
index f7c8f99..81202e5 100644
--- a/arch/powerpc/Kconfig
+++ b/arch/powerpc/Kconfig
@@ -871,6 +871,21 @@ config SECCOMP

If unsure, say Y. Only embedded should say N here.

+config PPC64_MEMORY_PROTECTION_KEYS
+ prompt "PowerPC Memory Protection Keys"
+ def_bool y
+ # Note: only available in 64-bit mode
+ depends on PPC64
+ select ARCH_USES_HIGH_VMA_FLAGS
+ select ARCH_HAS_PKEYS
+ ---help---
+ Memory Protection Keys provides a mechanism for enforcing
+ page-based protections, but without requiring modification of the
+ page tables when an application changes protection domains.
+
+ For details, see Documentation/powerpc/protection-keys.txt
+
+ If unsure, say y.
endmenu

config ISA_DMA_API
diff --git a/arch/powerpc/include/asm/book3s/64/mmu.h b/arch/powerpc/include/asm/book3s/64/mmu.h
index 77529a3..0c0a2a8 100644
--- a/arch/powerpc/include/asm/book3s/64/mmu.h
+++ b/arch/powerpc/include/asm/book3s/64/mmu.h
@@ -108,6 +108,16 @@ struct patb_entry {
#ifdef CONFIG_SPAPR_TCE_IOMMU
struct list_head iommu_group_mem_list;
#endif
+
+#ifdef CONFIG_PPC64_MEMORY_PROTECTION_KEYS
+ /*
+ * Each bit represents one protection key.
+ * bit set -> key allocated
+ * bit unset -> key available for allocation
+ */
+ u32 pkey_allocation_map;
+ s16 execute_only_pkey; /* key holding execute-only protection */
+#endif
} mm_context_t;

/*
diff --git a/arch/powerpc/include/asm/book3s/64/pgtable.h b/arch/powerpc/include/asm/book3s/64/pgtable.h
index 85bc987..87e9a89 100644
--- a/arch/powerpc/include/asm/book3s/64/pgtable.h
+++ b/arch/powerpc/include/asm/book3s/64/pgtable.h
@@ -428,6 +428,68 @@ static inline void huge_ptep_set_wrprotect(struct mm_struct *mm,
pte_update(mm, addr, ptep, 0, _PAGE_PRIVILEGED, 1);
}

+
+#ifdef CONFIG_PPC64_MEMORY_PROTECTION_KEYS
+
+#include <asm/reg.h>
+static inline u64 read_amr(void)
+{
+ return mfspr(SPRN_AMR);
+}
+static inline void write_amr(u64 value)
+{
+ mtspr(SPRN_AMR, value);
+}
+static inline u64 read_iamr(void)
+{
+ return mfspr(SPRN_IAMR);
+}
+static inline void write_iamr(u64 value)
+{
+ mtspr(SPRN_IAMR, value);
+}
+static inline u64 read_uamor(void)
+{
+ return mfspr(SPRN_UAMOR);
+}
+static inline void write_uamor(u64 value)
+{
+ mtspr(SPRN_UAMOR, value);
+}
+
+#else /* CONFIG_PPC64_MEMORY_PROTECTION_KEYS */
+
+static inline u64 read_amr(void)
+{
+ WARN(1, "%s called with MEMORY PROTECTION KEYS disabled\n", __func__);
+ return -1;
+}
+static inline void write_amr(u64 value)
+{
+ WARN(1, "%s called with MEMORY PROTECTION KEYS disabled\n", __func__);
+}
+static inline u64 read_uamor(void)
+{
+ WARN(1, "%s called with MEMORY PROTECTION KEYS disabled\n", __func__);
+ return -1;
+}
+static inline void write_uamor(u64 value)
+{
+ WARN(1, "%s called with MEMORY PROTECTION KEYS disabled\n", __func__);
+}
+static inline u64 read_iamr(void)
+{
+ WARN(1, "%s called with MEMORY PROTECTION KEYS disabled\n", __func__);
+ return -1;
+}
+static inline void write_iamr(u64 value)
+{
+ WARN(1, "%s called with MEMORY PROTECTION KEYS disabled\n", __func__);
+}
+
+#endif /* CONFIG_PPC64_MEMORY_PROTECTION_KEYS */
+
+
#define __HAVE_ARCH_PTEP_GET_AND_CLEAR
static inline pte_t ptep_get_and_clear(struct mm_struct *mm,
unsigned long addr, pte_t *ptep)
diff --git a/arch/powerpc/include/asm/pkeys.h b/arch/powerpc/include/asm/pkeys.h
new file mode 100644
index 0000000..7bc8746
--- /dev/null
+++ b/arch/powerpc/include/asm/pkeys.h
@@ -0,0 +1,124 @@
+#ifndef _ASM_PPC64_PKEYS_H
+#define _ASM_PPC64_PKEYS_H
+
+
+#define arch_max_pkey() 32
+
+#define AMR_AD_BIT 0x1UL
+#define AMR_WD_BIT 0x2UL
+#define IAMR_EX_BIT 0x1UL
+#define AMR_BITS_PER_PKEY 2
+#define ARCH_VM_PKEY_FLAGS (VM_PKEY_BIT0 | \
+ VM_PKEY_BIT1 | \
+ VM_PKEY_BIT2 | \
+ VM_PKEY_BIT3 | \
+ VM_PKEY_BIT4)
+
+/*
+ * Bits are in BE format.
+ * NOTE: key 31, 1, 0 are not used.
+ * key 0 is used by default. It give read/write/execute permission.
+ * key 31 is reserved by the hypervisor.
+ * key 1 is recommended to be not used.
+ * PowerISA(3.0) page 1015, programming note.
+ */
+#define PKEY_INITIAL_ALLOCAION 0xc0000001
+
+#define pkeybit_mask(pkey) (0x1 << (arch_max_pkey() - pkey - 1))
+
+#define mm_pkey_allocation_map(mm) (mm->context.pkey_allocation_map)
+
+#define mm_set_pkey_allocated(mm, pkey) { \
+ mm_pkey_allocation_map(mm) |= pkeybit_mask(pkey); \
+}
+
+#define mm_set_pkey_free(mm, pkey) { \
+ mm_pkey_allocation_map(mm) &= ~pkeybit_mask(pkey); \
+}
+
+#define mm_set_pkey_is_allocated(mm, pkey) \
+ (mm_pkey_allocation_map(mm) & pkeybit_mask(pkey))
+
+#define mm_set_pkey_is_reserved(mm, pkey) (PKEY_INITIAL_ALLOCAION & \
+ pkeybit_mask(pkey))
+
+static inline bool mm_pkey_is_allocated(struct mm_struct *mm, int pkey)
+{
+ /* a reserved key is never considered as 'explicitly allocated' */
+ return (!mm_set_pkey_is_reserved(mm, pkey) &&
+ mm_set_pkey_is_allocated(mm, pkey));
+}
+
+/*
+ * Returns a positive, 5-bit key on success, or -1 on failure.
+ */
+static inline int mm_pkey_alloc(struct mm_struct *mm)
+{
+ /*
+ * Note: this is the one and only place we make sure
+ * that the pkey is valid as far as the hardware is
+ * concerned. The rest of the kernel trusts that
+ * only good, valid pkeys come out of here.
+ */
+ u32 all_pkeys_mask = (u32)(~(0x0));
+ int ret;
+
+ /*
+ * Are we out of pkeys? We must handle this specially
+ * because ffz() behavior is undefined if there are no
+ * zeros.
+ */
+ if (mm_pkey_allocation_map(mm) == all_pkeys_mask)
+ return -1;
+
+ ret = arch_max_pkey() -
+ ffz((u32)mm_pkey_allocation_map(mm))
+ - 1;
+ mm_set_pkey_allocated(mm, ret);
+ return ret;
+}
+
+static inline int mm_pkey_free(struct mm_struct *mm, int pkey)
+{
+ if (!mm_pkey_is_allocated(mm, pkey))
+ return -EINVAL;
+
+ mm_set_pkey_free(mm, pkey);
+
+ return 0;
+}
+
+/*
+ * Try to dedicate one of the protection keys to be used as an
+ * execute-only protection key.
+ */
+extern int __execute_only_pkey(struct mm_struct *mm);
+static inline int execute_only_pkey(struct mm_struct *mm)
+{
+ return __execute_only_pkey(mm);
+}
+
+extern int __arch_override_mprotect_pkey(struct vm_area_struct *vma,
+ int prot, int pkey);
+static inline int arch_override_mprotect_pkey(struct vm_area_struct *vma,
+ int prot, int pkey)
+{
+ return __arch_override_mprotect_pkey(vma, prot, pkey);
+}
+
+extern int __arch_set_user_pkey_access(struct task_struct *tsk, int pkey,
+ unsigned long init_val);
+static inline int arch_set_user_pkey_access(struct task_struct *tsk, int pkey,
+ unsigned long init_val)
+{
+ return __arch_set_user_pkey_access(tsk, pkey, init_val);
+}
+
+static inline pkey_mm_init(struct mm_struct *mm)
+{
+ mm_pkey_allocation_map(mm) = PKEY_INITIAL_ALLOCAION;
+ /* -1 means unallocated or invalid */
+ mm->context.execute_only_pkey = -1;
+}
+
+#endif /*_ASM_PPC64_PKEYS_H */
diff --git a/arch/powerpc/include/asm/systbl.h b/arch/powerpc/include/asm/systbl.h
index 1c94708..22dd776 100644
--- a/arch/powerpc/include/asm/systbl.h
+++ b/arch/powerpc/include/asm/systbl.h
@@ -388,3 +388,5 @@
COMPAT_SYS_SPU(pwritev2)
SYSCALL(kexec_file_load)
SYSCALL(statx)
+SYSCALL(pkey_alloc)
+SYSCALL(pkey_free)
diff --git a/arch/powerpc/include/asm/unistd.h b/arch/powerpc/include/asm/unistd.h
index 9ba11db..e0273bc 100644
--- a/arch/powerpc/include/asm/unistd.h
+++ b/arch/powerpc/include/asm/unistd.h
@@ -12,13 +12,11 @@
#include <uapi/asm/unistd.h>


-#define NR_syscalls 384
+#define NR_syscalls 386

#define __NR__exit __NR_exit

#define __IGNORE_pkey_mprotect
-#define __IGNORE_pkey_alloc
-#define __IGNORE_pkey_free

#ifndef __ASSEMBLY__

diff --git a/arch/powerpc/include/uapi/asm/unistd.h b/arch/powerpc/include/uapi/asm/unistd.h
index b85f142..7993a07 100644
--- a/arch/powerpc/include/uapi/asm/unistd.h
+++ b/arch/powerpc/include/uapi/asm/unistd.h
@@ -394,5 +394,7 @@
#define __NR_pwritev2 381
#define __NR_kexec_file_load 382
#define __NR_statx 383
+#define __NR_pkey_alloc 384
+#define __NR_pkey_free 385

#endif /* _UAPI_ASM_POWERPC_UNISTD_H_ */
diff --git a/arch/powerpc/mm/Makefile b/arch/powerpc/mm/Makefile
index 7414034..8cc2ff1 100644
--- a/arch/powerpc/mm/Makefile
+++ b/arch/powerpc/mm/Makefile
@@ -45,3 +45,4 @@ obj-$(CONFIG_PPC_COPRO_BASE) += copro_fault.o
obj-$(CONFIG_SPAPR_TCE_IOMMU) += mmu_context_iommu.o
obj-$(CONFIG_PPC_PTDUMP) += dump_linuxpagetables.o
obj-$(CONFIG_PPC_HTDUMP) += dump_hashpagetable.o
+obj-$(CONFIG_PPC64_MEMORY_PROTECTION_KEYS) += pkeys.o
diff --git a/arch/powerpc/mm/mmu_context_book3s64.c b/arch/powerpc/mm/mmu_context_book3s64.c
index c6dca2a..2da9931 100644
--- a/arch/powerpc/mm/mmu_context_book3s64.c
+++ b/arch/powerpc/mm/mmu_context_book3s64.c
@@ -16,6 +16,7 @@
#include <linux/string.h>
#include <linux/types.h>
#include <linux/mm.h>
+#include <linux/pkeys.h>
#include <linux/spinlock.h>
#include <linux/idr.h>
#include <linux/export.h>
@@ -120,6 +121,10 @@ static int hash__init_new_context(struct mm_struct *mm)

subpage_prot_init_new_context(mm);

+#ifdef CONFIG_PPC64_MEMORY_PROTECTION_KEYS
+ pkey_mm_init(mm);
+#endif /* CONFIG_PPC64_MEMORY_PROTECTION_KEYS */
+
return index;
}

diff --git a/arch/powerpc/mm/pkeys.c b/arch/powerpc/mm/pkeys.c
new file mode 100644
index 0000000..b97366e
--- /dev/null
+++ b/arch/powerpc/mm/pkeys.c
@@ -0,0 +1,88 @@
+/*
+ * PowerPC Memory Protection Keys management
+ * Copyright (c) 2015, Intel Corporation.
+ * Copyright (c) 2017, IBM Corporation.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms and conditions of the GNU General Public License,
+ * version 2, as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
+ * more details.
+ */
+#include <linux/pkeys.h> /* PKEY_* */
+#include <uapi/asm-generic/mman-common.h>
+
+
+/*
+ * set the access right in AMR IAMR and UAMOR register
+ * for @pkey to that specified in @init_val.
+ */
+int __arch_set_user_pkey_access(struct task_struct *tsk, int pkey,
+ unsigned long init_val)
+{
+ u64 old_amr, old_uamor, old_iamr;
+ int pkey_shift = (arch_max_pkey()-pkey-1) * AMR_BITS_PER_PKEY;
+ u64 new_amr_bits = 0x0ul;
+ u64 new_iamr_bits = 0x0ul;
+ u64 new_uamor_bits = 0x3ul;
+
+ /* Set the bits we need in AMR: */
+ if (init_val & PKEY_DISABLE_ACCESS)
+ new_amr_bits |= AMR_AD_BIT;
+ if (init_val & PKEY_DISABLE_WRITE)
+ new_amr_bits |= AMR_WD_BIT;
+
+ /*
+ * By default execute is disabled.
+ * To enable execute, PKEY_ENABLE_EXECUTE
+ * needs to be specified.
+ */
+ if ((init_val & PKEY_DISABLE_EXECUTE))
+ new_iamr_bits |= IAMR_EX_BIT;
+
+ /* Shift the bits in to the correct place in AMR for pkey: */
+ new_amr_bits <<= pkey_shift;
+ new_iamr_bits <<= pkey_shift;
+ new_uamor_bits <<= pkey_shift;
+
+ /* Get old AMR and mask off any old bits in place: */
+ old_amr = read_amr();
+ old_amr &= ~((u64)(AMR_AD_BIT|AMR_WD_BIT) << pkey_shift);
+
+ old_iamr = read_iamr();
+ old_iamr &= ~(0x3ul << pkey_shift);
+
+ old_uamor = read_uamor();
+ old_uamor &= ~(0x3ul << pkey_shift);
+
+ /* Write old part along with new part: */
+ write_amr(old_amr | new_amr_bits);
+ write_iamr(old_iamr | new_iamr_bits);
+ write_uamor(old_uamor | new_uamor_bits);
+
+ return 0;
+}
+
+int __execute_only_pkey(struct mm_struct *mm)
+{
+ return -1;
+}
+
+/*
+ * This should only be called for *plain* mprotect calls.
+ */
+int __arch_override_mprotect_pkey(struct vm_area_struct *vma, int prot,
+ int pkey)
+{
+ /*
+ * Is this an mprotect_pkey() call? If so, never
+ * override the value that came from the user.
+ */
+ if (pkey != -1)
+ return pkey;
+
+ return 0;
+}
--
1.8.3.1

2017-06-27 10:17:24

by Ram Pai

Subject: [RFC v4 07/17] powerpc: make the hash functions protection-key aware

Prepare the hash functions to be aware of protection keys.
This key will later be used to program the HPTE.

Signed-off-by: Ram Pai <[email protected]>
---
arch/powerpc/include/asm/book3s/64/hash.h | 2 +-
arch/powerpc/include/asm/book3s/64/mmu-hash.h | 14 ++++++-----
arch/powerpc/mm/hash64_4k.c | 4 ++--
arch/powerpc/mm/hash64_64k.c | 8 +++----
arch/powerpc/mm/hash_utils_64.c | 34 ++++++++++++++++++---------
arch/powerpc/mm/hugepage-hash64.c | 4 ++--
arch/powerpc/mm/hugetlbpage-hash64.c | 5 ++--
arch/powerpc/mm/mem.c | 1 +
arch/powerpc/mm/mmu_decl.h | 5 +++-
9 files changed, 48 insertions(+), 29 deletions(-)

diff --git a/arch/powerpc/include/asm/book3s/64/hash.h b/arch/powerpc/include/asm/book3s/64/hash.h
index 4e957b0..3c1ef01 100644
--- a/arch/powerpc/include/asm/book3s/64/hash.h
+++ b/arch/powerpc/include/asm/book3s/64/hash.h
@@ -92,7 +92,7 @@ static inline int hash__pgd_bad(pgd_t pgd)

extern void hpte_need_flush(struct mm_struct *mm, unsigned long addr,
pte_t *ptep, unsigned long pte, int huge);
-extern unsigned long htab_convert_pte_flags(unsigned long pteflags);
+extern unsigned long htab_convert_pte_flags(unsigned long pteflags, int pkey);
/* Atomic PTE updates */
static inline unsigned long hash__pte_update(struct mm_struct *mm,
unsigned long addr,
diff --git a/arch/powerpc/include/asm/book3s/64/mmu-hash.h b/arch/powerpc/include/asm/book3s/64/mmu-hash.h
index 6981a52..aa3c299 100644
--- a/arch/powerpc/include/asm/book3s/64/mmu-hash.h
+++ b/arch/powerpc/include/asm/book3s/64/mmu-hash.h
@@ -430,11 +430,11 @@ static inline unsigned long hpt_hash(unsigned long vpn,
#define HPTE_NOHPTE_UPDATE 0x2

extern int __hash_page_4K(unsigned long ea, unsigned long access,
- unsigned long vsid, pte_t *ptep, unsigned long trap,
- unsigned long flags, int ssize, int subpage_prot);
+ unsigned long vsid, pte_t *ptep, unsigned long trap,
+ unsigned long flags, int ssize, int subpage_prot, int pkey);
extern int __hash_page_64K(unsigned long ea, unsigned long access,
unsigned long vsid, pte_t *ptep, unsigned long trap,
- unsigned long flags, int ssize);
+ unsigned long flags, int ssize, int pkey);
struct mm_struct;
unsigned int hash_page_do_lazy_icache(unsigned int pp, pte_t pte, int trap);
extern int hash_page_mm(struct mm_struct *mm, unsigned long ea,
@@ -444,16 +444,18 @@ extern int hash_page(unsigned long ea, unsigned long access, unsigned long trap,
unsigned long dsisr);
int __hash_page_huge(unsigned long ea, unsigned long access, unsigned long vsid,
pte_t *ptep, unsigned long trap, unsigned long flags,
- int ssize, unsigned int shift, unsigned int mmu_psize);
+ int ssize, unsigned int shift, unsigned int mmu_psize,
+ int pkey);
#ifdef CONFIG_TRANSPARENT_HUGEPAGE
extern int __hash_page_thp(unsigned long ea, unsigned long access,
unsigned long vsid, pmd_t *pmdp, unsigned long trap,
- unsigned long flags, int ssize, unsigned int psize);
+ unsigned long flags, int ssize, unsigned int psize,
+ int pkey);
#else
static inline int __hash_page_thp(unsigned long ea, unsigned long access,
unsigned long vsid, pmd_t *pmdp,
unsigned long trap, unsigned long flags,
- int ssize, unsigned int psize)
+ int ssize, unsigned int psize, int pkey)
{
BUG();
return -1;
diff --git a/arch/powerpc/mm/hash64_4k.c b/arch/powerpc/mm/hash64_4k.c
index 6fa450c..6765ba2 100644
--- a/arch/powerpc/mm/hash64_4k.c
+++ b/arch/powerpc/mm/hash64_4k.c
@@ -18,7 +18,7 @@

int __hash_page_4K(unsigned long ea, unsigned long access, unsigned long vsid,
pte_t *ptep, unsigned long trap, unsigned long flags,
- int ssize, int subpg_prot)
+ int ssize, int subpg_prot, int pkey)
{
unsigned long hpte_group;
unsigned long rflags, pa;
@@ -53,7 +53,7 @@ int __hash_page_4K(unsigned long ea, unsigned long access, unsigned long vsid,
* PP bits. _PAGE_USER is already PP bit 0x2, so we only
* need to add in 0x1 if it's a read-only user page
*/
- rflags = htab_convert_pte_flags(new_pte);
+ rflags = htab_convert_pte_flags(new_pte, pkey);

if (cpu_has_feature(CPU_FTR_NOEXECUTE) &&
!cpu_has_feature(CPU_FTR_COHERENT_ICACHE))
diff --git a/arch/powerpc/mm/hash64_64k.c b/arch/powerpc/mm/hash64_64k.c
index 1a68cb1..9ce4d7b 100644
--- a/arch/powerpc/mm/hash64_64k.c
+++ b/arch/powerpc/mm/hash64_64k.c
@@ -47,7 +47,7 @@ static unsigned long mark_subptegroup_valid(unsigned long ptev, unsigned long in

int __hash_page_4K(unsigned long ea, unsigned long access, unsigned long vsid,
pte_t *ptep, unsigned long trap, unsigned long flags,
- int ssize, int subpg_prot)
+ int ssize, int subpg_prot, int pkey)
{
real_pte_t rpte;
unsigned long *hidxp;
@@ -85,7 +85,7 @@ int __hash_page_4K(unsigned long ea, unsigned long access, unsigned long vsid,
* Handle the subpage protection bits
*/
subpg_pte = new_pte & ~subpg_prot;
- rflags = htab_convert_pte_flags(subpg_pte);
+ rflags = htab_convert_pte_flags(subpg_pte, pkey);

if (cpu_has_feature(CPU_FTR_NOEXECUTE) &&
!cpu_has_feature(CPU_FTR_COHERENT_ICACHE)) {
@@ -219,7 +219,7 @@ int __hash_page_4K(unsigned long ea, unsigned long access, unsigned long vsid,

int __hash_page_64K(unsigned long ea, unsigned long access,
unsigned long vsid, pte_t *ptep, unsigned long trap,
- unsigned long flags, int ssize)
+ unsigned long flags, int ssize, int pkey)
{
unsigned long hpte_group;
unsigned long rflags, pa;
@@ -256,7 +256,7 @@ int __hash_page_64K(unsigned long ea, unsigned long access,
new_pte |= _PAGE_DIRTY;
} while (!pte_xchg(ptep, __pte(old_pte), __pte(new_pte)));

- rflags = htab_convert_pte_flags(new_pte);
+ rflags = htab_convert_pte_flags(new_pte, pkey);

if (cpu_has_feature(CPU_FTR_NOEXECUTE) &&
!cpu_has_feature(CPU_FTR_COHERENT_ICACHE))
diff --git a/arch/powerpc/mm/hash_utils_64.c b/arch/powerpc/mm/hash_utils_64.c
index f2095ce..2254ff0 100644
--- a/arch/powerpc/mm/hash_utils_64.c
+++ b/arch/powerpc/mm/hash_utils_64.c
@@ -35,6 +35,7 @@
#include <linux/memblock.h>
#include <linux/context_tracking.h>
#include <linux/libfdt.h>
+#include <linux/pkeys.h>

#include <asm/debugfs.h>
#include <asm/processor.h>
@@ -176,7 +177,7 @@
* - We make sure R is always set and never lost
* - C is _PAGE_DIRTY, and *should* always be set for a writeable mapping
*/
-unsigned long htab_convert_pte_flags(unsigned long pteflags)
+unsigned long htab_convert_pte_flags(unsigned long pteflags, int pkey)
{
unsigned long rflags = 0;

@@ -244,7 +245,7 @@ int htab_bolt_mapping(unsigned long vstart, unsigned long vend,
shift = mmu_psize_defs[psize].shift;
step = 1 << shift;

- prot = htab_convert_pte_flags(prot);
+ prot = htab_convert_pte_flags(prot, 0);

DBG("htab_bolt_mapping(%lx..%lx -> %lx (%lx,%d,%d)\n",
vstart, vend, pstart, prot, psize, ssize);
@@ -1228,7 +1229,7 @@ int hash_page_mm(struct mm_struct *mm, unsigned long ea,
unsigned hugeshift;
const struct cpumask *tmp;
int rc, user_region = 0;
- int psize, ssize;
+ int psize, ssize, pkey = 0;

DBG_LOW("hash_page(ea=%016lx, access=%lx, trap=%lx\n",
ea, access, trap);
@@ -1317,11 +1318,13 @@ int hash_page_mm(struct mm_struct *mm, unsigned long ea,
if (hugeshift) {
if (is_thp)
rc = __hash_page_thp(ea, access, vsid, (pmd_t *)ptep,
- trap, flags, ssize, psize);
+ trap, flags, ssize, psize,
+ pkey);
#ifdef CONFIG_HUGETLB_PAGE
else
rc = __hash_page_huge(ea, access, vsid, ptep, trap,
- flags, ssize, hugeshift, psize);
+ flags, ssize, hugeshift, psize,
+ pkey);
#else
else {
/*
@@ -1381,7 +1384,8 @@ int hash_page_mm(struct mm_struct *mm, unsigned long ea,
#ifdef CONFIG_PPC_64K_PAGES
if (psize == MMU_PAGE_64K)
rc = __hash_page_64K(ea, access, vsid, ptep, trap,
- flags, ssize);
+ flags, ssize,
+ pkey);
else
#endif /* CONFIG_PPC_64K_PAGES */
{
@@ -1390,7 +1394,8 @@ int hash_page_mm(struct mm_struct *mm, unsigned long ea,
rc = -2;
else
rc = __hash_page_4K(ea, access, vsid, ptep, trap,
- flags, ssize, spp);
+ flags, ssize, spp,
+ pkey);
}

/* Dump some info in case of hash insertion failure, they should
@@ -1486,8 +1491,9 @@ static bool should_hash_preload(struct mm_struct *mm, unsigned long ea)
}
#endif

-void hash_preload(struct mm_struct *mm, unsigned long ea,
- unsigned long access, unsigned long trap)
+void hash_preload_pkey(struct mm_struct *mm, unsigned long ea,
+ unsigned long access, unsigned long trap,
+ int pkey)
{
int hugepage_shift;
unsigned long vsid;
@@ -1548,11 +1554,11 @@ void hash_preload(struct mm_struct *mm, unsigned long ea,
#ifdef CONFIG_PPC_64K_PAGES
if (mm->context.user_psize == MMU_PAGE_64K)
rc = __hash_page_64K(ea, access, vsid, ptep, trap,
- update_flags, ssize);
+ update_flags, ssize, pkey);
else
#endif /* CONFIG_PPC_64K_PAGES */
rc = __hash_page_4K(ea, access, vsid, ptep, trap, update_flags,
- ssize, subpage_protection(mm, ea));
+ ssize, subpage_protection(mm, ea), pkey);

/* Dump some info in case of hash insertion failure, they should
* never happen so it is really useful to know if/when they do
@@ -1566,6 +1572,12 @@ void hash_preload(struct mm_struct *mm, unsigned long ea,
local_irq_restore(flags);
}

+void hash_preload(struct mm_struct *mm, unsigned long ea,
+ unsigned long access, unsigned long trap)
+{
+ hash_preload_pkey(mm, ea, access, trap, 0);
+}
+
#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
static inline void tm_flush_hash_page(int local)
{
diff --git a/arch/powerpc/mm/hugepage-hash64.c b/arch/powerpc/mm/hugepage-hash64.c
index f20d16f..cc4855e 100644
--- a/arch/powerpc/mm/hugepage-hash64.c
+++ b/arch/powerpc/mm/hugepage-hash64.c
@@ -20,7 +20,7 @@

int __hash_page_thp(unsigned long ea, unsigned long access, unsigned long vsid,
pmd_t *pmdp, unsigned long trap, unsigned long flags,
- int ssize, unsigned int psize)
+ int ssize, unsigned int psize, int pkey)
{
unsigned int index, valid;
unsigned char *hpte_slot_array;
@@ -51,7 +51,7 @@ int __hash_page_thp(unsigned long ea, unsigned long access, unsigned long vsid,
new_pmd |= _PAGE_DIRTY;
} while (!pmd_xchg(pmdp, __pmd(old_pmd), __pmd(new_pmd)));

- rflags = htab_convert_pte_flags(new_pmd);
+ rflags = htab_convert_pte_flags(new_pmd, pkey);

#if 0
if (!cpu_has_feature(CPU_FTR_COHERENT_ICACHE)) {
diff --git a/arch/powerpc/mm/hugetlbpage-hash64.c b/arch/powerpc/mm/hugetlbpage-hash64.c
index a84bb44..fe7d671 100644
--- a/arch/powerpc/mm/hugetlbpage-hash64.c
+++ b/arch/powerpc/mm/hugetlbpage-hash64.c
@@ -20,7 +20,8 @@ extern long hpte_insert_repeating(unsigned long hash, unsigned long vpn,

int __hash_page_huge(unsigned long ea, unsigned long access, unsigned long vsid,
pte_t *ptep, unsigned long trap, unsigned long flags,
- int ssize, unsigned int shift, unsigned int mmu_psize)
+ int ssize, unsigned int shift, unsigned int mmu_psize,
+ int pkey)
{
unsigned long vpn;
unsigned long old_pte, new_pte;
@@ -60,7 +61,7 @@ int __hash_page_huge(unsigned long ea, unsigned long access, unsigned long vsid,
new_pte |= _PAGE_DIRTY;
} while(!pte_xchg(ptep, __pte(old_pte), __pte(new_pte)));

- rflags = htab_convert_pte_flags(new_pte);
+ rflags = htab_convert_pte_flags(new_pte, pkey);

sz = ((1UL) << shift);
if (!cpu_has_feature(CPU_FTR_COHERENT_ICACHE))
diff --git a/arch/powerpc/mm/mem.c b/arch/powerpc/mm/mem.c
index 9ee536e..ec890d3 100644
--- a/arch/powerpc/mm/mem.c
+++ b/arch/powerpc/mm/mem.c
@@ -36,6 +36,7 @@
#include <linux/hugetlb.h>
#include <linux/slab.h>
#include <linux/vmalloc.h>
+#include <linux/pkeys.h>

#include <asm/pgalloc.h>
#include <asm/prom.h>
diff --git a/arch/powerpc/mm/mmu_decl.h b/arch/powerpc/mm/mmu_decl.h
index f988db6..e425c27 100644
--- a/arch/powerpc/mm/mmu_decl.h
+++ b/arch/powerpc/mm/mmu_decl.h
@@ -82,10 +82,13 @@ static inline void _tlbivax_bcast(unsigned long address, unsigned int pid,

#else /* CONFIG_PPC_MMU_NOHASH */

+extern void hash_preload_pkey(struct mm_struct *mm, unsigned long ea,
+ unsigned long access, unsigned long trap,
+ int pkey);
+
extern void hash_preload(struct mm_struct *mm, unsigned long ea,
unsigned long access, unsigned long trap);

-
extern void _tlbie(unsigned long address);
extern void _tlbia(void);

--
1.8.3.1

2017-06-27 10:17:19

by Ram Pai

Subject: [RFC v4 06/17] powerpc: Implementation for sys_mprotect_pkey() system call

This system call, associates the pkey with vma corresponding to
the given address range.

Signed-off-by: Ram Pai <[email protected]>
---
arch/powerpc/include/asm/mman.h | 8 ++-
arch/powerpc/include/asm/pkeys.h | 17 ++++++-
arch/powerpc/include/asm/systbl.h | 1 +
arch/powerpc/include/asm/unistd.h | 4 +-
arch/powerpc/include/uapi/asm/unistd.h | 1 +
arch/powerpc/mm/pkeys.c | 93 +++++++++++++++++++++++++++++++++-
6 files changed, 117 insertions(+), 7 deletions(-)

diff --git a/arch/powerpc/include/asm/mman.h b/arch/powerpc/include/asm/mman.h
index 30922f6..067eec2 100644
--- a/arch/powerpc/include/asm/mman.h
+++ b/arch/powerpc/include/asm/mman.h
@@ -13,6 +13,7 @@

#include <asm/cputable.h>
#include <linux/mm.h>
+#include <linux/pkeys.h>
#include <asm/cpu_has_feature.h>

/*
@@ -22,7 +23,12 @@
static inline unsigned long arch_calc_vm_prot_bits(unsigned long prot,
unsigned long pkey)
{
- return (prot & PROT_SAO) ? VM_SAO : 0;
+#ifdef CONFIG_PPC64_MEMORY_PROTECTION_KEYS
+ return (((prot & PROT_SAO) ? VM_SAO : 0) |
+ pkey_to_vmflag_bits(pkey));
+#else
+ return ((prot & PROT_SAO) ? VM_SAO : 0);
+#endif
}
#define arch_calc_vm_prot_bits(prot, pkey) arch_calc_vm_prot_bits(prot, pkey)

diff --git a/arch/powerpc/include/asm/pkeys.h b/arch/powerpc/include/asm/pkeys.h
index 7bc8746..41bf5d4 100644
--- a/arch/powerpc/include/asm/pkeys.h
+++ b/arch/powerpc/include/asm/pkeys.h
@@ -14,6 +14,15 @@
VM_PKEY_BIT3 | \
VM_PKEY_BIT4)

+static inline unsigned long pkey_to_vmflag_bits(int pkey)
+{
+ return (((pkey & 0x1UL) ? VM_PKEY_BIT0 : 0x0UL) |
+ ((pkey & 0x2UL) ? VM_PKEY_BIT1 : 0x0UL) |
+ ((pkey & 0x4UL) ? VM_PKEY_BIT2 : 0x0UL) |
+ ((pkey & 0x8UL) ? VM_PKEY_BIT3 : 0x0UL) |
+ ((pkey & 0x10UL) ? VM_PKEY_BIT4 : 0x0UL));
+}
+
/*
* Bits are in BE format.
* NOTE: key 31, 1, 0 are not used.
@@ -42,6 +51,12 @@
#define mm_set_pkey_is_reserved(mm, pkey) (PKEY_INITIAL_ALLOCAION & \
pkeybit_mask(pkey))

+
+static inline int vma_pkey(struct vm_area_struct *vma)
+{
+ return (vma->vm_flags & ARCH_VM_PKEY_FLAGS) >> VM_PKEY_SHIFT;
+}
+
static inline bool mm_pkey_is_allocated(struct mm_struct *mm, int pkey)
{
/* a reserved key is never considered as 'explicitly allocated' */
@@ -114,7 +129,7 @@ static inline int arch_set_user_pkey_access(struct task_struct *tsk, int pkey,
return __arch_set_user_pkey_access(tsk, pkey, init_val);
}

-static inline pkey_mm_init(struct mm_struct *mm)
+static inline void pkey_mm_init(struct mm_struct *mm)
{
mm_pkey_allocation_map(mm) = PKEY_INITIAL_ALLOCAION;
/* -1 means unallocated or invalid */
diff --git a/arch/powerpc/include/asm/systbl.h b/arch/powerpc/include/asm/systbl.h
index 22dd776..b33b551 100644
--- a/arch/powerpc/include/asm/systbl.h
+++ b/arch/powerpc/include/asm/systbl.h
@@ -390,3 +390,4 @@
SYSCALL(statx)
SYSCALL(pkey_alloc)
SYSCALL(pkey_free)
+SYSCALL(pkey_mprotect)
diff --git a/arch/powerpc/include/asm/unistd.h b/arch/powerpc/include/asm/unistd.h
index e0273bc..daf1ba9 100644
--- a/arch/powerpc/include/asm/unistd.h
+++ b/arch/powerpc/include/asm/unistd.h
@@ -12,12 +12,10 @@
#include <uapi/asm/unistd.h>


-#define NR_syscalls 386
+#define NR_syscalls 387

#define __NR__exit __NR_exit

-#define __IGNORE_pkey_mprotect
-
#ifndef __ASSEMBLY__

#include <linux/types.h>
diff --git a/arch/powerpc/include/uapi/asm/unistd.h b/arch/powerpc/include/uapi/asm/unistd.h
index 7993a07..71ae45e 100644
--- a/arch/powerpc/include/uapi/asm/unistd.h
+++ b/arch/powerpc/include/uapi/asm/unistd.h
@@ -396,5 +396,6 @@
#define __NR_statx 383
#define __NR_pkey_alloc 384
#define __NR_pkey_free 385
+#define __NR_pkey_mprotect 386

#endif /* _UAPI_ASM_POWERPC_UNISTD_H_ */
diff --git a/arch/powerpc/mm/pkeys.c b/arch/powerpc/mm/pkeys.c
index b97366e..11a32b3 100644
--- a/arch/powerpc/mm/pkeys.c
+++ b/arch/powerpc/mm/pkeys.c
@@ -15,6 +15,17 @@
#include <linux/pkeys.h> /* PKEY_* */
#include <uapi/asm-generic/mman-common.h>

+#define pkeyshift(pkey) ((arch_max_pkey()-pkey-1) * AMR_BITS_PER_PKEY)
+
+static inline bool pkey_allows_readwrite(int pkey)
+{
+ int pkey_shift = pkeyshift(pkey);
+
+ if (!(read_uamor() & (0x3UL << pkey_shift)))
+ return true;
+
+ return !(read_amr() & ((AMR_AD_BIT|AMR_WD_BIT) << pkey_shift));
+}

/*
* set the access right in AMR IAMR and UAMOR register
@@ -68,7 +79,60 @@ int __arch_set_user_pkey_access(struct task_struct *tsk, int pkey,

int __execute_only_pkey(struct mm_struct *mm)
{
- return -1;
+ bool need_to_set_mm_pkey = false;
+ int execute_only_pkey = mm->context.execute_only_pkey;
+ int ret;
+
+ /* Do we need to assign a pkey for mm's execute-only maps? */
+ if (execute_only_pkey == -1) {
+ /* Go allocate one to use, which might fail */
+ execute_only_pkey = mm_pkey_alloc(mm);
+ if (execute_only_pkey < 0)
+ return -1;
+ need_to_set_mm_pkey = true;
+ }
+
+ /*
+ * We do not want to go through the relatively costly
+ * dance to set AMR if we do not need to. Check it
+ * first and assume that if the execute-only pkey is
+ * readwrite-disabled than we do not have to set it
+ * ourselves.
+ */
+ if (!need_to_set_mm_pkey &&
+ !pkey_allows_readwrite(execute_only_pkey))
+ return execute_only_pkey;
+
+ /*
+ * Set up AMR so that it denies access for everything
+ * other than execution.
+ */
+ ret = __arch_set_user_pkey_access(current, execute_only_pkey,
+ (PKEY_DISABLE_ACCESS | PKEY_DISABLE_WRITE));
+ /*
+ * If the AMR-set operation failed somehow, just return
+ * 0 and effectively disable execute-only support.
+ */
+ if (ret) {
+ mm_set_pkey_free(mm, execute_only_pkey);
+ return -1;
+ }
+
+ /* We got one, store it and use it from here on out */
+ if (need_to_set_mm_pkey)
+ mm->context.execute_only_pkey = execute_only_pkey;
+ return execute_only_pkey;
+}
+
+static inline bool vma_is_pkey_exec_only(struct vm_area_struct *vma)
+{
+ /* Do this check first since the vm_flags should be hot */
+ if ((vma->vm_flags & (VM_READ | VM_WRITE | VM_EXEC)) != VM_EXEC)
+ return false;
+ if (vma_pkey(vma) != vma->vm_mm->context.execute_only_pkey)
+ return false;
+
+ return true;
}

/*
@@ -84,5 +148,30 @@ int __arch_override_mprotect_pkey(struct vm_area_struct *vma, int prot,
if (pkey != -1)
return pkey;

- return 0;
+ /*
+ * Look for a protection-key-drive execute-only mapping
+ * which is now being given permissions that are not
+ * execute-only. Move it back to the default pkey.
+ */
+ if (vma_is_pkey_exec_only(vma) &&
+ (prot & (PROT_READ|PROT_WRITE))) {
+ return 0;
+ }
+ /*
+ * The mapping is execute-only. Go try to get the
+ * execute-only protection key. If we fail to do that,
+ * fall through as if we do not have execute-only
+ * support.
+ */
+ if (prot == PROT_EXEC) {
+ pkey = execute_only_pkey(vma->vm_mm);
+ if (pkey > 0)
+ return pkey;
+ }
+ /*
+ * This is a vanilla, non-pkey mprotect (or we failed to
+ * setup execute-only), inherit the pkey from the VMA we
+ * are working on.
+ */
+ return vma_pkey(vma);
}
--
1.8.3.1

2017-06-27 10:18:19

by Ram Pai

Subject: [RFC v4 01/17] mm: introduce an additional vma bit for powerpc pkey

Currently there are only 4bits in the vma flags to support 16 keys
on x86. powerpc supports 32 keys, which needs 5bits. This patch
introduces an addition bit in the vma flags.

Signed-off-by: Ram Pai <[email protected]>
---
fs/proc/task_mmu.c | 6 +++++-
include/linux/mm.h | 18 +++++++++++++-----
2 files changed, 18 insertions(+), 6 deletions(-)

diff --git a/fs/proc/task_mmu.c b/fs/proc/task_mmu.c
index f0c8b33..2ddc298 100644
--- a/fs/proc/task_mmu.c
+++ b/fs/proc/task_mmu.c
@@ -666,12 +666,16 @@ static void show_smap_vma_flags(struct seq_file *m, struct vm_area_struct *vma)
[ilog2(VM_MERGEABLE)] = "mg",
[ilog2(VM_UFFD_MISSING)]= "um",
[ilog2(VM_UFFD_WP)] = "uw",
-#ifdef CONFIG_X86_INTEL_MEMORY_PROTECTION_KEYS
+#ifdef CONFIG_ARCH_HAS_PKEYS
/* These come out via ProtectionKey: */
[ilog2(VM_PKEY_BIT0)] = "",
[ilog2(VM_PKEY_BIT1)] = "",
[ilog2(VM_PKEY_BIT2)] = "",
[ilog2(VM_PKEY_BIT3)] = "",
+#endif /* CONFIG_ARCH_HAS_PKEYS */
+#ifdef CONFIG_PPC64_MEMORY_PROTECTION_KEYS
+ /* Additional bit in ProtectionKey: */
+ [ilog2(VM_PKEY_BIT4)] = "",
#endif
};
size_t i;
diff --git a/include/linux/mm.h b/include/linux/mm.h
index 7cb17c6..3d35bcc 100644
--- a/include/linux/mm.h
+++ b/include/linux/mm.h
@@ -208,21 +208,29 @@ extern int overcommit_kbytes_handler(struct ctl_table *, int, void __user *,
#define VM_HIGH_ARCH_BIT_1 33 /* bit only usable on 64-bit architectures */
#define VM_HIGH_ARCH_BIT_2 34 /* bit only usable on 64-bit architectures */
#define VM_HIGH_ARCH_BIT_3 35 /* bit only usable on 64-bit architectures */
+#define VM_HIGH_ARCH_BIT_4 36 /* bit only usable on 64-bit arch */
#define VM_HIGH_ARCH_0 BIT(VM_HIGH_ARCH_BIT_0)
#define VM_HIGH_ARCH_1 BIT(VM_HIGH_ARCH_BIT_1)
#define VM_HIGH_ARCH_2 BIT(VM_HIGH_ARCH_BIT_2)
#define VM_HIGH_ARCH_3 BIT(VM_HIGH_ARCH_BIT_3)
+#define VM_HIGH_ARCH_4 BIT(VM_HIGH_ARCH_BIT_4)
#endif /* CONFIG_ARCH_USES_HIGH_VMA_FLAGS */

-#if defined(CONFIG_X86)
-# define VM_PAT VM_ARCH_1 /* PAT reserves whole VMA at once (x86) */
-#if defined (CONFIG_X86_INTEL_MEMORY_PROTECTION_KEYS)
+#ifdef CONFIG_ARCH_HAS_PKEYS
# define VM_PKEY_SHIFT VM_HIGH_ARCH_BIT_0
-# define VM_PKEY_BIT0 VM_HIGH_ARCH_0 /* A protection key is a 4-bit value */
+# define VM_PKEY_BIT0 VM_HIGH_ARCH_0
# define VM_PKEY_BIT1 VM_HIGH_ARCH_1
# define VM_PKEY_BIT2 VM_HIGH_ARCH_2
# define VM_PKEY_BIT3 VM_HIGH_ARCH_3
-#endif
+#endif /* CONFIG_ARCH_HAS_PKEYS */
+
+#if defined(CONFIG_PPC64_MEMORY_PROTECTION_KEYS)
+# define VM_PKEY_BIT4 VM_HIGH_ARCH_4 /* additional key bit used on ppc64 */
+#endif /* CONFIG_PPC64_MEMORY_PROTECTION_KEYS */
+
+
+#if defined(CONFIG_X86)
+# define VM_PAT VM_ARCH_1 /* PAT reserves whole VMA at once (x86) */
#elif defined(CONFIG_PPC)
# define VM_SAO VM_ARCH_1 /* Strong Access Ordering (powerpc) */
#elif defined(CONFIG_PARISC)
--
1.8.3.1

2017-06-27 10:47:21

by Balbir Singh

Subject: Re: [RFC v4 00/17] powerpc: Memory Protection Keys

On Tue, 2017-06-27 at 03:11 -0700, Ram Pai wrote:
> Memory protection keys enable applications to protect its
> address space from inadvertent access or corruption from
> itself.
>
> The overall idea:
>
> A process allocates a key and associates it with
> a address range within its address space.
> The process than can dynamically set read/write
> permissions on the key without involving the
> kernel. Any code that violates the permissions
> off the address space; as defined by its associated
> key, will receive a segmentation fault.
>
> This patch series enables the feature on PPC64 HPTE
> platform.
>
> ISA3.0 section 5.7.13 describes the detailed specifications.
>
>
> Testing:
> This patch series has passed all the protection key
> tests available in the selftests directory.
> The tests are updated to work on both x86 and powerpc.
>
> version v4:
> (1) patches no more depend on the pte bits to program
> the hpte -- comment by Balbir
> (2) documentation updates
> (3) fixed a bug in the selftest.
> (4) unlike x86, powerpc lets signal handler change key
> permission bits; the change will persist across
> signal handler boundaries. Earlier we allowed
> the signal handler to modify a field in the siginfo
> structure which would than be used by the kernel
> to program the key protection register (AMR)
> -- resolves a issue raised by Ben.
> "Calls to sys_swapcontext with a made-up context
> will end up with a crap AMR if done by code who
> didn't know about that register".
> (5) these changes enable protection keys on 4k-page
> kernel aswell.

I have not looked at the full series, but it seems cleaner than the original
one and the side-effect is that we can support 4k as well. Nice!

Balbir Singh.

2017-06-27 10:55:10

by Balbir Singh

Subject: Re: [RFC v4 01/17] mm: introduce an additional vma bit for powerpc pkey

On Tue, 2017-06-27 at 03:11 -0700, Ram Pai wrote:
> Currently there are only 4bits in the vma flags to support 16 keys
> on x86. powerpc supports 32 keys, which needs 5bits. This patch
> introduces an addition bit in the vma flags.
>
> Signed-off-by: Ram Pai <[email protected]>
> ---
> fs/proc/task_mmu.c | 6 +++++-
> include/linux/mm.h | 18 +++++++++++++-----
> 2 files changed, 18 insertions(+), 6 deletions(-)
>
> diff --git a/fs/proc/task_mmu.c b/fs/proc/task_mmu.c
> index f0c8b33..2ddc298 100644
> --- a/fs/proc/task_mmu.c
> +++ b/fs/proc/task_mmu.c
> @@ -666,12 +666,16 @@ static void show_smap_vma_flags(struct seq_file *m, struct vm_area_struct *vma)
> [ilog2(VM_MERGEABLE)] = "mg",
> [ilog2(VM_UFFD_MISSING)]= "um",
> [ilog2(VM_UFFD_WP)] = "uw",
> -#ifdef CONFIG_X86_INTEL_MEMORY_PROTECTION_KEYS
> +#ifdef CONFIG_ARCH_HAS_PKEYS
> /* These come out via ProtectionKey: */
> [ilog2(VM_PKEY_BIT0)] = "",
> [ilog2(VM_PKEY_BIT1)] = "",
> [ilog2(VM_PKEY_BIT2)] = "",
> [ilog2(VM_PKEY_BIT3)] = "",
> +#endif /* CONFIG_ARCH_HAS_PKEYS */
> +#ifdef CONFIG_PPC64_MEMORY_PROTECTION_KEYS
> + /* Additional bit in ProtectionKey: */
> + [ilog2(VM_PKEY_BIT4)] = "",
> #endif

Not sure why these are linked with smap bits, but I guess the keys live
in the Supervisor Mode Access Prevention area?

Balbir Singh.

2017-06-27 11:33:13

by Balbir Singh

Subject: Re: [RFC v4 03/17] x86: key creation with PKEY_DISABLE_EXECUTE disallowed

On Tue, 2017-06-27 at 03:11 -0700, Ram Pai wrote:
> x86 does not support disabling execute permissions on a pkey.
>
> Signed-off-by: Ram Pai <[email protected]>
> ---
> arch/x86/kernel/fpu/xstate.c | 3 +++
> 1 file changed, 3 insertions(+)
>
> diff --git a/arch/x86/kernel/fpu/xstate.c b/arch/x86/kernel/fpu/xstate.c
> index c24ac1e..d582631 100644
> --- a/arch/x86/kernel/fpu/xstate.c
> +++ b/arch/x86/kernel/fpu/xstate.c
> @@ -900,6 +900,9 @@ int arch_set_user_pkey_access(struct task_struct *tsk, int pkey,
> if (!boot_cpu_has(X86_FEATURE_OSPKE))
> return -EINVAL;
>
> + if (init_val & PKEY_DISABLE_EXECUTE)
> + return -EINVAL;
> +
> /* Set the bits we need in PKRU: */
> if (init_val & PKEY_DISABLE_ACCESS)
> new_pkru_bits |= PKRU_AD_BIT;

I am not an x86 expert. IIUC, execute disable is done via allocating an
execute_only_pkey and checking vma_key via AD + vma_flags against VM_EXEC.

Your patch looks good to me

Acked-by: Balbir Singh <[email protected]>

Balbir Singh.

2017-06-27 11:33:51

by Balbir Singh

Subject: Re: [RFC v4 02/17] mm: ability to disable execute permission on a key at creation

On Tue, 2017-06-27 at 03:11 -0700, Ram Pai wrote:
> Currently sys_pkey_create() provides the ability to disable read
> and write permission on the key, at creation. powerpc has the
> hardware support to disable execute on a pkey as well.This patch
> enhances the interface to let disable execute at key creation
> time. x86 does not allow this. Hence the next patch will add
> ability in x86 to return error if PKEY_DISABLE_EXECUTE is
> specified.
>
> Signed-off-by: Ram Pai <[email protected]>
> ---

Acked-by: Balbir Singh <[email protected]>

2017-06-27 15:24:47

by Aneesh Kumar K.V

Subject: Re: [RFC v4 09/17] powerpc: call the hash functions with the correct pkey value

On Tuesday 27 June 2017 03:41 PM, Ram Pai wrote:
> Pass the correct protection key value to the hash functions on
> page fault.
>
> Signed-off-by: Ram Pai <[email protected]>
> ---
> arch/powerpc/include/asm/pkeys.h | 11 +++++++++++
> arch/powerpc/mm/hash_utils_64.c | 4 ++++
> arch/powerpc/mm/mem.c | 6 ++++++
> 3 files changed, 21 insertions(+)
>
> diff --git a/arch/powerpc/include/asm/pkeys.h b/arch/powerpc/include/asm/pkeys.h
> index ef1c601..1370b3f 100644
> --- a/arch/powerpc/include/asm/pkeys.h
> +++ b/arch/powerpc/include/asm/pkeys.h
> @@ -74,6 +74,17 @@ static inline bool mm_pkey_is_allocated(struct mm_struct *mm, int pkey)
> }
>
> /*
> + * return the protection key of the vma corresponding to the
> + * given effective address @ea.
> + */
> +static inline int mm_pkey(struct mm_struct *mm, unsigned long ea)
> +{
> + struct vm_area_struct *vma = find_vma(mm, ea);
> + int pkey = vma ? vma_pkey(vma) : 0;
> + return pkey;
> +}
> +
> +/*
>

That is not going to work in hash fault path right ? We can't do a
find_vma there without holding the mmap_sem

-aneesh

2017-06-28 01:50:28

by Michael Ellerman

Subject: Re: [RFC v4 17/17] procfs: display the protection-key number associated with a vma

Ram Pai <[email protected]> writes:

> Display the pkey number associated with the vma in smaps of a task.
> The key will be seen as below:
>
> VmFlags: rd wr mr mw me dw ac key=0

Why wouldn't we just emit a "ProtectionKey:" line like x86 does?

See their arch_show_smap().

You should probably also do what x86 does, which is to not display the
key on CPUs that don't support keys.

cheers

2017-06-28 07:12:49

by Ram Pai

Subject: Re: [RFC v4 09/17] powerpc: call the hash functions with the correct pkey value

On Tue, Jun 27, 2017 at 08:54:07PM +0530, Aneesh Kumar K.V wrote:
>
>
> On Tuesday 27 June 2017 03:41 PM, Ram Pai wrote:
> >Pass the correct protection key value to the hash functions on
> >page fault.
> >
> >Signed-off-by: Ram Pai <[email protected]>
> >---
> > arch/powerpc/include/asm/pkeys.h | 11 +++++++++++
> > arch/powerpc/mm/hash_utils_64.c | 4 ++++
> > arch/powerpc/mm/mem.c | 6 ++++++
> > 3 files changed, 21 insertions(+)
> >
> >diff --git a/arch/powerpc/include/asm/pkeys.h b/arch/powerpc/include/asm/pkeys.h
> >index ef1c601..1370b3f 100644
> >--- a/arch/powerpc/include/asm/pkeys.h
> >+++ b/arch/powerpc/include/asm/pkeys.h
> >@@ -74,6 +74,17 @@ static inline bool mm_pkey_is_allocated(struct mm_struct *mm, int pkey)
> > }
> >
> > /*
> >+ * return the protection key of the vma corresponding to the
> >+ * given effective address @ea.
> >+ */
> >+static inline int mm_pkey(struct mm_struct *mm, unsigned long ea)
> >+{
> >+ struct vm_area_struct *vma = find_vma(mm, ea);
> >+ int pkey = vma ? vma_pkey(vma) : 0;
> >+ return pkey;
> >+}
> >+
> >+/*
> >
>
> That is not going to work in hash fault path right ? We can't do a
> find_vma there without holding the mmap_sem

There is a fundamental problem with this new design. Looks like we can't
hold a lock in that path, without badly hurting the performance.

I am moving back to the old design. Cant by-pass the pte. The
keys will be programmed into the pte which will than be used
to program the hpte.

RP