This series replaces get_fs/set_fs and removes it from MIPS arch code.
Changes in v2:
- added copy_from_kernel_nofault_allowed() for !EVA to restrict
access of __get/__put_kernel_nofault
- replaced __get_data macro by helper functions
- removed leftover set_fs calls in ftrace.c
- further cleanup uaccess.h
Thomas Bogendoerfer (4):
MIPS: kernel: Remove not needed set_fs calls
MIPS: uaccess: Added __get/__put_kernel_nofault
MIPS: uaccess: Remove get_fs/set_fs call sites
MIPS: Remove get_fs/set_fs
arch/mips/Kconfig | 1 -
arch/mips/include/asm/processor.h | 4 -
arch/mips/include/asm/thread_info.h | 6 -
arch/mips/include/asm/uaccess.h | 436 +++++++++++-----------------
arch/mips/kernel/access-helper.h | 53 ++++
arch/mips/kernel/asm-offsets.c | 1 -
arch/mips/kernel/ftrace.c | 8 -
arch/mips/kernel/process.c | 2 -
arch/mips/kernel/scall32-o32.S | 4 +-
arch/mips/kernel/traps.c | 105 +++----
arch/mips/kernel/unaligned.c | 199 +++++--------
arch/mips/lib/memcpy.S | 28 +-
arch/mips/lib/memset.S | 3 -
arch/mips/lib/strncpy_user.S | 48 +--
arch/mips/lib/strnlen_user.S | 44 +--
arch/mips/mm/Makefile | 4 +
arch/mips/mm/maccess.c | 10 +
17 files changed, 392 insertions(+), 564 deletions(-)
create mode 100644 arch/mips/kernel/access-helper.h
create mode 100644 arch/mips/mm/maccess.c
--
2.29.2
Added __get/__put_kernel_nofault as preparation for removing
get/set_fs.
Signed-off-by: Thomas Bogendoerfer <[email protected]>
---
arch/mips/include/asm/uaccess.h | 24 ++++++++++++++++++++++++
arch/mips/mm/Makefile | 4 ++++
arch/mips/mm/maccess.c | 10 ++++++++++
3 files changed, 38 insertions(+)
create mode 100644 arch/mips/mm/maccess.c
diff --git a/arch/mips/include/asm/uaccess.h b/arch/mips/include/asm/uaccess.h
index d273a3857809..c5cab0b8f902 100644
--- a/arch/mips/include/asm/uaccess.h
+++ b/arch/mips/include/asm/uaccess.h
@@ -355,6 +355,18 @@ do { \
(val) = __gu_tmp.t; \
}
+#define HAVE_GET_KERNEL_NOFAULT
+
+#define __get_kernel_nofault(dst, src, type, err_label) \
+do { \
+ int __gu_err; \
+ \
+ __get_kernel_common(*((type *)(dst)), sizeof(type), \
+ (__force type *)(src)); \
+ if (unlikely(__gu_err)) \
+ goto err_label; \
+} while (0)
+
#ifndef CONFIG_EVA
#define __put_kernel_common(ptr, size) __put_user_common(ptr, size)
#else
@@ -483,6 +495,18 @@ do { \
extern void __put_user_unknown(void);
+#define __put_kernel_nofault(dst, src, type, err_label) \
+do { \
+ type __pu_val; \
+ int __pu_err = 0; \
+ \
+ __pu_val = *(__force type *)(src); \
+ __put_kernel_common(((type *)(dst)), sizeof(type)); \
+ if (unlikely(__pu_err)) \
+ goto err_label; \
+} while (0)
+
+
/*
* We're generating jump to subroutines which will be outside the range of
* jump instructions
diff --git a/arch/mips/mm/Makefile b/arch/mips/mm/Makefile
index 865926a37775..76e3ee8882fa 100644
--- a/arch/mips/mm/Makefile
+++ b/arch/mips/mm/Makefile
@@ -22,6 +22,10 @@ else
obj-y += uasm-mips.o
endif
+ifndef CONFIG_EVA
+obj-y += maccess.o
+endif
+
obj-$(CONFIG_32BIT) += ioremap.o pgtable-32.o
obj-$(CONFIG_64BIT) += ioremap64.o pgtable-64.o
obj-$(CONFIG_HIGHMEM) += highmem.o
diff --git a/arch/mips/mm/maccess.c b/arch/mips/mm/maccess.c
new file mode 100644
index 000000000000..58173842c6be
--- /dev/null
+++ b/arch/mips/mm/maccess.c
@@ -0,0 +1,10 @@
+// SPDX-License-Identifier: GPL-2.0-only
+
+#include <linux/uaccess.h>
+#include <linux/kernel.h>
+
+bool copy_from_kernel_nofault_allowed(const void *unsafe_src, size_t size)
+{
+ /* highest bit set means kernel space */
+ return (unsigned long)unsafe_src >> (BITS_PER_LONG - 1);
+}
--
2.29.2
flush_icache_range always does flush kernel address ranges, so no
need to do the set_fs dance.
Signed-off-by: Thomas Bogendoerfer <[email protected]>
---
arch/mips/kernel/ftrace.c | 8 --------
1 file changed, 8 deletions(-)
diff --git a/arch/mips/kernel/ftrace.c b/arch/mips/kernel/ftrace.c
index 666b9969c1bd..8c401e42301c 100644
--- a/arch/mips/kernel/ftrace.c
+++ b/arch/mips/kernel/ftrace.c
@@ -90,7 +90,6 @@ static int ftrace_modify_code_2(unsigned long ip, unsigned int new_code1,
unsigned int new_code2)
{
int faulted;
- mm_segment_t old_fs;
safe_store_code(new_code1, ip, faulted);
if (unlikely(faulted))
@@ -102,10 +101,7 @@ static int ftrace_modify_code_2(unsigned long ip, unsigned int new_code1,
return -EFAULT;
ip -= 4;
- old_fs = get_fs();
- set_fs(KERNEL_DS);
flush_icache_range(ip, ip + 8);
- set_fs(old_fs);
return 0;
}
@@ -114,7 +110,6 @@ static int ftrace_modify_code_2r(unsigned long ip, unsigned int new_code1,
unsigned int new_code2)
{
int faulted;
- mm_segment_t old_fs;
ip += 4;
safe_store_code(new_code2, ip, faulted);
@@ -126,10 +121,7 @@ static int ftrace_modify_code_2r(unsigned long ip, unsigned int new_code1,
if (unlikely(faulted))
return -EFAULT;
- old_fs = get_fs();
- set_fs(KERNEL_DS);
flush_icache_range(ip, ip + 8);
- set_fs(old_fs);
return 0;
}
--
2.29.2
Use new helpers to access user/kernel for functions, which are used with
user/kernel pointers. Instead of dealing with get_fs/set_fs select
user/kernel access via parameter.
Signed-off-by: Thomas Bogendoerfer <[email protected]>
---
arch/mips/kernel/access-helper.h | 53 ++++++++
arch/mips/kernel/traps.c | 105 +++++++---------
arch/mips/kernel/unaligned.c | 199 +++++++++++--------------------
3 files changed, 171 insertions(+), 186 deletions(-)
create mode 100644 arch/mips/kernel/access-helper.h
diff --git a/arch/mips/kernel/access-helper.h b/arch/mips/kernel/access-helper.h
new file mode 100644
index 000000000000..04e93203f165
--- /dev/null
+++ b/arch/mips/kernel/access-helper.h
@@ -0,0 +1,53 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+
+#include <asm/uaccess.h>
+
+#define __get_user_nofault(dst, src, type, err_label) \
+do { \
+ int __gu_err; \
+ \
+ __get_user_common(*((type *)(dst)), sizeof(type), \
+ (__force type *)(src)); \
+ if (unlikely(__gu_err)) \
+ goto err_label; \
+} while (0)
+
+
+static inline int __get_addr(unsigned long *a, unsigned long *p, bool user)
+{
+ if (user)
+ __get_user_nofault(a, p, unsigned long, fault);
+ else
+ __get_kernel_nofault(a, p, unsigned long, fault);
+
+ return 0;
+
+fault:
+ return -EFAULT;
+}
+
+static inline int __get_inst16(u16 *i, u16 *p, bool user)
+{
+ if (user)
+ __get_user_nofault(i, p, u16, fault);
+ else
+ __get_kernel_nofault(i, p, u16, fault);
+
+ return 0;
+
+fault:
+ return -EFAULT;
+}
+
+static inline int __get_inst32(u32 *i, u32 *p, bool user)
+{
+ if (user)
+ __get_user_nofault(i, p, u32, fault);
+ else
+ __get_kernel_nofault(i, p, u32, fault);
+
+ return 0;
+
+fault:
+ return -EFAULT;
+}
diff --git a/arch/mips/kernel/traps.c b/arch/mips/kernel/traps.c
index 808b8b61ded1..0b4e06303c55 100644
--- a/arch/mips/kernel/traps.c
+++ b/arch/mips/kernel/traps.c
@@ -72,6 +72,8 @@
#include <asm/mach-loongson64/cpucfg-emul.h>
+#include "access-helper.h"
+
extern void check_wait(void);
extern asmlinkage void rollback_handle_int(void);
extern asmlinkage void handle_int(void);
@@ -108,7 +110,8 @@ void (*board_bind_eic_interrupt)(int irq, int regset);
void (*board_ebase_setup)(void);
void(*board_cache_error_setup)(void);
-static void show_raw_backtrace(unsigned long reg29, const char *loglvl)
+static void show_raw_backtrace(unsigned long reg29, const char *loglvl,
+ bool user)
{
unsigned long *sp = (unsigned long *)(reg29 & ~3);
unsigned long addr;
@@ -118,9 +121,7 @@ static void show_raw_backtrace(unsigned long reg29, const char *loglvl)
printk("%s\n", loglvl);
#endif
while (!kstack_end(sp)) {
- unsigned long __user *p =
- (unsigned long __user *)(unsigned long)sp++;
- if (__get_user(addr, p)) {
+ if (__get_addr(&addr, sp++, user)) {
printk("%s (Bad stack address)", loglvl);
break;
}
@@ -141,7 +142,7 @@ __setup("raw_show_trace", set_raw_show_trace);
#endif
static void show_backtrace(struct task_struct *task, const struct pt_regs *regs,
- const char *loglvl)
+ const char *loglvl, bool user)
{
unsigned long sp = regs->regs[29];
unsigned long ra = regs->regs[31];
@@ -151,7 +152,7 @@ static void show_backtrace(struct task_struct *task, const struct pt_regs *regs,
task = current;
if (raw_show_trace || user_mode(regs) || !__kernel_text_address(pc)) {
- show_raw_backtrace(sp, loglvl);
+ show_raw_backtrace(sp, loglvl, user);
return;
}
printk("%sCall Trace:\n", loglvl);
@@ -167,12 +168,12 @@ static void show_backtrace(struct task_struct *task, const struct pt_regs *regs,
* with at least a bit of error checking ...
*/
static void show_stacktrace(struct task_struct *task,
- const struct pt_regs *regs, const char *loglvl)
+ const struct pt_regs *regs, const char *loglvl, bool user)
{
const int field = 2 * sizeof(unsigned long);
- long stackdata;
+ unsigned long stackdata;
int i;
- unsigned long __user *sp = (unsigned long __user *)regs->regs[29];
+ unsigned long *sp = (unsigned long *)regs->regs[29];
printk("%sStack :", loglvl);
i = 0;
@@ -186,7 +187,7 @@ static void show_stacktrace(struct task_struct *task,
break;
}
- if (__get_user(stackdata, sp++)) {
+ if (__get_addr(&stackdata, sp++, user)) {
pr_cont(" (Bad stack address)");
break;
}
@@ -195,13 +196,12 @@ static void show_stacktrace(struct task_struct *task,
i++;
}
pr_cont("\n");
- show_backtrace(task, regs, loglvl);
+ show_backtrace(task, regs, loglvl, user);
}
void show_stack(struct task_struct *task, unsigned long *sp, const char *loglvl)
{
struct pt_regs regs;
- mm_segment_t old_fs = get_fs();
regs.cp0_status = KSU_KERNEL;
if (sp) {
@@ -217,33 +217,41 @@ void show_stack(struct task_struct *task, unsigned long *sp, const char *loglvl)
prepare_frametrace(®s);
}
}
- /*
- * show_stack() deals exclusively with kernel mode, so be sure to access
- * the stack in the kernel (not user) address space.
- */
- set_fs(KERNEL_DS);
- show_stacktrace(task, ®s, loglvl);
- set_fs(old_fs);
+ show_stacktrace(task, ®s, loglvl, false);
}
-static void show_code(unsigned int __user *pc)
+static void show_code(void *pc, bool user)
{
long i;
- unsigned short __user *pc16 = NULL;
+ unsigned short *pc16 = NULL;
printk("Code:");
if ((unsigned long)pc & 1)
- pc16 = (unsigned short __user *)((unsigned long)pc & ~1);
+ pc16 = (u16 *)((unsigned long)pc & ~1);
+
for(i = -3 ; i < 6 ; i++) {
- unsigned int insn;
- if (pc16 ? __get_user(insn, pc16 + i) : __get_user(insn, pc + i)) {
- pr_cont(" (Bad address in epc)\n");
- break;
+ if (pc16) {
+ u16 insn16;
+
+ if (__get_inst16(&insn16, pc16 + i, user))
+ goto bad_address;
+
+ pr_cont("%c%04x%c", (i?' ':'<'), insn16, (i?' ':'>'));
+ } else {
+ u32 insn32;
+
+ if (__get_inst32(&insn32, (u32 *)pc + i, user))
+ goto bad_address;
+
+ pr_cont("%c%08x%c", (i?' ':'<'), insn32, (i?' ':'>'));
}
- pr_cont("%c%0*x%c", (i?' ':'<'), pc16 ? 4 : 8, insn, (i?' ':'>'));
}
pr_cont("\n");
+ return;
+
+bad_address:
+ pr_cont(" (Bad address in epc)\n\n");
}
static void __show_regs(const struct pt_regs *regs)
@@ -356,7 +364,6 @@ void show_regs(struct pt_regs *regs)
void show_registers(struct pt_regs *regs)
{
const int field = 2 * sizeof(unsigned long);
- mm_segment_t old_fs = get_fs();
__show_regs(regs);
print_modules();
@@ -371,13 +378,9 @@ void show_registers(struct pt_regs *regs)
printk("*HwTLS: %0*lx\n", field, tls);
}
- if (!user_mode(regs))
- /* Necessary for getting the correct stack content */
- set_fs(KERNEL_DS);
- show_stacktrace(current, regs, KERN_DEFAULT);
- show_code((unsigned int __user *) regs->cp0_epc);
+ show_stacktrace(current, regs, KERN_DEFAULT, user_mode(regs));
+ show_code((void *)regs->cp0_epc, user_mode(regs));
printk("\n");
- set_fs(old_fs);
}
static DEFINE_RAW_SPINLOCK(die_lock);
@@ -1022,18 +1025,14 @@ asmlinkage void do_bp(struct pt_regs *regs)
unsigned long epc = msk_isa16_mode(exception_epc(regs));
unsigned int opcode, bcode;
enum ctx_state prev_state;
- mm_segment_t seg;
-
- seg = get_fs();
- if (!user_mode(regs))
- set_fs(KERNEL_DS);
+ bool user = user_mode(regs);
prev_state = exception_enter();
current->thread.trap_nr = (regs->cp0_cause >> 2) & 0x1f;
if (get_isa16_mode(regs->cp0_epc)) {
u16 instr[2];
- if (__get_user(instr[0], (u16 __user *)epc))
+ if (__get_inst16(&instr[0], (u16 *)epc, user))
goto out_sigsegv;
if (!cpu_has_mmips) {
@@ -1044,13 +1043,13 @@ asmlinkage void do_bp(struct pt_regs *regs)
bcode = instr[0] & 0xf;
} else {
/* 32-bit microMIPS BREAK */
- if (__get_user(instr[1], (u16 __user *)(epc + 2)))
+ if (__get_inst16(&instr[1], (u16 *)(epc + 2), user))
goto out_sigsegv;
opcode = (instr[0] << 16) | instr[1];
bcode = (opcode >> 6) & ((1 << 20) - 1);
}
} else {
- if (__get_user(opcode, (unsigned int __user *)epc))
+ if (__get_inst32(&opcode, (u32 *)epc, user))
goto out_sigsegv;
bcode = (opcode >> 6) & ((1 << 20) - 1);
}
@@ -1100,7 +1099,6 @@ asmlinkage void do_bp(struct pt_regs *regs)
do_trap_or_bp(regs, bcode, TRAP_BRKPT, "Break");
out:
- set_fs(seg);
exception_exit(prev_state);
return;
@@ -1114,25 +1112,21 @@ asmlinkage void do_tr(struct pt_regs *regs)
u32 opcode, tcode = 0;
enum ctx_state prev_state;
u16 instr[2];
- mm_segment_t seg;
+ bool user = user_mode(regs);
unsigned long epc = msk_isa16_mode(exception_epc(regs));
- seg = get_fs();
- if (!user_mode(regs))
- set_fs(KERNEL_DS);
-
prev_state = exception_enter();
current->thread.trap_nr = (regs->cp0_cause >> 2) & 0x1f;
if (get_isa16_mode(regs->cp0_epc)) {
- if (__get_user(instr[0], (u16 __user *)(epc + 0)) ||
- __get_user(instr[1], (u16 __user *)(epc + 2)))
+ if (__get_inst16(&instr[0], (u16 *)(epc + 0), user) ||
+ __get_inst16(&instr[1], (u16 *)(epc + 2), user))
goto out_sigsegv;
opcode = (instr[0] << 16) | instr[1];
/* Immediate versions don't provide a code. */
if (!(opcode & OPCODE))
tcode = (opcode >> 12) & ((1 << 4) - 1);
} else {
- if (__get_user(opcode, (u32 __user *)epc))
+ if (__get_inst32(&opcode, (u32 *)epc, user))
goto out_sigsegv;
/* Immediate versions don't provide a code. */
if (!(opcode & OPCODE))
@@ -1142,7 +1136,6 @@ asmlinkage void do_tr(struct pt_regs *regs)
do_trap_or_bp(regs, tcode, 0, "Trap");
out:
- set_fs(seg);
exception_exit(prev_state);
return;
@@ -1591,7 +1584,6 @@ asmlinkage void do_mcheck(struct pt_regs *regs)
{
int multi_match = regs->cp0_status & ST0_TS;
enum ctx_state prev_state;
- mm_segment_t old_fs = get_fs();
prev_state = exception_enter();
show_regs(regs);
@@ -1602,12 +1594,7 @@ asmlinkage void do_mcheck(struct pt_regs *regs)
dump_tlb_all();
}
- if (!user_mode(regs))
- set_fs(KERNEL_DS);
-
- show_code((unsigned int __user *) regs->cp0_epc);
-
- set_fs(old_fs);
+ show_code((void *)regs->cp0_epc, user_mode(regs));
/*
* Some chips may have other causes of machine check (e.g. SB1
diff --git a/arch/mips/kernel/unaligned.c b/arch/mips/kernel/unaligned.c
index 126a5f3f4e4c..1f3b20a8c377 100644
--- a/arch/mips/kernel/unaligned.c
+++ b/arch/mips/kernel/unaligned.c
@@ -93,6 +93,8 @@
#include <asm/mmu_context.h>
#include <linux/uaccess.h>
+#include "access-helper.h"
+
enum {
UNALIGNED_ACTION_QUIET,
UNALIGNED_ACTION_SIGNAL,
@@ -112,9 +114,8 @@ static void emulate_load_store_insn(struct pt_regs *regs,
unsigned long origpc, orig31, value;
union mips_instruction insn;
unsigned int res;
-#ifdef CONFIG_EVA
- mm_segment_t seg;
-#endif
+ bool user = user_mode(regs);
+
origpc = (unsigned long)pc;
orig31 = regs->regs[31];
@@ -123,7 +124,7 @@ static void emulate_load_store_insn(struct pt_regs *regs,
/*
* This load never faults.
*/
- __get_user(insn.word, pc);
+ __get_inst32(&insn.word, pc, user);
switch (insn.i_format.opcode) {
/*
@@ -163,7 +164,7 @@ static void emulate_load_store_insn(struct pt_regs *regs,
if (insn.dsp_format.func == lx_op) {
switch (insn.dsp_format.op) {
case lwx_op:
- if (!access_ok(addr, 4))
+ if (user && !access_ok(addr, 4))
goto sigbus;
LoadW(addr, value, res);
if (res)
@@ -172,7 +173,7 @@ static void emulate_load_store_insn(struct pt_regs *regs,
regs->regs[insn.dsp_format.rd] = value;
break;
case lhx_op:
- if (!access_ok(addr, 2))
+ if (user && !access_ok(addr, 2))
goto sigbus;
LoadHW(addr, value, res);
if (res)
@@ -191,93 +192,66 @@ static void emulate_load_store_insn(struct pt_regs *regs,
* memory, so we need to "switch" the address limit to
* user space, so that address check can work properly.
*/
- seg = force_uaccess_begin();
switch (insn.spec3_format.func) {
case lhe_op:
- if (!access_ok(addr, 2)) {
- force_uaccess_end(seg);
+ if (!access_ok(addr, 2))
goto sigbus;
- }
LoadHWE(addr, value, res);
- if (res) {
- force_uaccess_end(seg);
+ if (res)
goto fault;
- }
compute_return_epc(regs);
regs->regs[insn.spec3_format.rt] = value;
break;
case lwe_op:
- if (!access_ok(addr, 4)) {
- force_uaccess_end(seg);
+ if (!access_ok(addr, 4))
goto sigbus;
- }
LoadWE(addr, value, res);
- if (res) {
- force_uaccess_end(seg);
+ if (res)
goto fault;
- }
compute_return_epc(regs);
regs->regs[insn.spec3_format.rt] = value;
break;
case lhue_op:
- if (!access_ok(addr, 2)) {
- force_uaccess_end(seg);
+ if (!access_ok(addr, 2))
goto sigbus;
- }
LoadHWUE(addr, value, res);
- if (res) {
- force_uaccess_end(seg);
+ if (res)
goto fault;
- }
compute_return_epc(regs);
regs->regs[insn.spec3_format.rt] = value;
break;
case she_op:
- if (!access_ok(addr, 2)) {
- force_uaccess_end(seg);
+ if (!access_ok(addr, 2))
goto sigbus;
- }
compute_return_epc(regs);
value = regs->regs[insn.spec3_format.rt];
StoreHWE(addr, value, res);
- if (res) {
- force_uaccess_end(seg);
+ if (res)
goto fault;
- }
break;
case swe_op:
- if (!access_ok(addr, 4)) {
- force_uaccess_end(seg);
+ if (!access_ok(addr, 4))
goto sigbus;
- }
compute_return_epc(regs);
value = regs->regs[insn.spec3_format.rt];
StoreWE(addr, value, res);
- if (res) {
- force_uaccess_end(seg);
+ if (res)
goto fault;
- }
break;
default:
- force_uaccess_end(seg);
goto sigill;
}
- force_uaccess_end(seg);
}
#endif
break;
case lh_op:
- if (!access_ok(addr, 2))
+ if (user && !access_ok(addr, 2))
goto sigbus;
- if (IS_ENABLED(CONFIG_EVA)) {
- if (uaccess_kernel())
- LoadHW(addr, value, res);
- else
- LoadHWE(addr, value, res);
- } else {
+ if (IS_ENABLED(CONFIG_EVA) && user)
+ LoadHWE(addr, value, res);
+ else
LoadHW(addr, value, res);
- }
if (res)
goto fault;
@@ -286,17 +260,13 @@ static void emulate_load_store_insn(struct pt_regs *regs,
break;
case lw_op:
- if (!access_ok(addr, 4))
+ if (user && !access_ok(addr, 4))
goto sigbus;
- if (IS_ENABLED(CONFIG_EVA)) {
- if (uaccess_kernel())
- LoadW(addr, value, res);
- else
- LoadWE(addr, value, res);
- } else {
+ if (IS_ENABLED(CONFIG_EVA) && user)
+ LoadWE(addr, value, res);
+ else
LoadW(addr, value, res);
- }
if (res)
goto fault;
@@ -305,17 +275,13 @@ static void emulate_load_store_insn(struct pt_regs *regs,
break;
case lhu_op:
- if (!access_ok(addr, 2))
+ if (user && !access_ok(addr, 2))
goto sigbus;
- if (IS_ENABLED(CONFIG_EVA)) {
- if (uaccess_kernel())
- LoadHWU(addr, value, res);
- else
- LoadHWUE(addr, value, res);
- } else {
+ if (IS_ENABLED(CONFIG_EVA) && user)
+ LoadHWUE(addr, value, res);
+ else
LoadHWU(addr, value, res);
- }
if (res)
goto fault;
@@ -332,7 +298,7 @@ static void emulate_load_store_insn(struct pt_regs *regs,
* would blow up, so for now we don't handle unaligned 64-bit
* instructions on 32-bit kernels.
*/
- if (!access_ok(addr, 4))
+ if (user && !access_ok(addr, 4))
goto sigbus;
LoadWU(addr, value, res);
@@ -355,7 +321,7 @@ static void emulate_load_store_insn(struct pt_regs *regs,
* would blow up, so for now we don't handle unaligned 64-bit
* instructions on 32-bit kernels.
*/
- if (!access_ok(addr, 8))
+ if (user && !access_ok(addr, 8))
goto sigbus;
LoadDW(addr, value, res);
@@ -370,40 +336,32 @@ static void emulate_load_store_insn(struct pt_regs *regs,
goto sigill;
case sh_op:
- if (!access_ok(addr, 2))
+ if (user && !access_ok(addr, 2))
goto sigbus;
compute_return_epc(regs);
value = regs->regs[insn.i_format.rt];
- if (IS_ENABLED(CONFIG_EVA)) {
- if (uaccess_kernel())
- StoreHW(addr, value, res);
- else
- StoreHWE(addr, value, res);
- } else {
+ if (IS_ENABLED(CONFIG_EVA) && user)
+ StoreHWE(addr, value, res);
+ else
StoreHW(addr, value, res);
- }
if (res)
goto fault;
break;
case sw_op:
- if (!access_ok(addr, 4))
+ if (user && !access_ok(addr, 4))
goto sigbus;
compute_return_epc(regs);
value = regs->regs[insn.i_format.rt];
- if (IS_ENABLED(CONFIG_EVA)) {
- if (uaccess_kernel())
- StoreW(addr, value, res);
- else
- StoreWE(addr, value, res);
- } else {
+ if (IS_ENABLED(CONFIG_EVA) && user)
+ StoreWE(addr, value, res);
+ else
StoreW(addr, value, res);
- }
if (res)
goto fault;
@@ -418,7 +376,7 @@ static void emulate_load_store_insn(struct pt_regs *regs,
* would blow up, so for now we don't handle unaligned 64-bit
* instructions on 32-bit kernels.
*/
- if (!access_ok(addr, 8))
+ if (user && !access_ok(addr, 8))
goto sigbus;
compute_return_epc(regs);
@@ -626,6 +584,7 @@ static void emulate_load_store_microMIPS(struct pt_regs *regs,
unsigned long origpc, contpc;
union mips_instruction insn;
struct mm_decoded_insn mminsn;
+ bool user = user_mode(regs);
origpc = regs->cp0_epc;
orig31 = regs->regs[31];
@@ -689,7 +648,7 @@ static void emulate_load_store_microMIPS(struct pt_regs *regs,
if (reg == 31)
goto sigbus;
- if (!access_ok(addr, 8))
+ if (user && !access_ok(addr, 8))
goto sigbus;
LoadW(addr, value, res);
@@ -708,7 +667,7 @@ static void emulate_load_store_microMIPS(struct pt_regs *regs,
if (reg == 31)
goto sigbus;
- if (!access_ok(addr, 8))
+ if (user && !access_ok(addr, 8))
goto sigbus;
value = regs->regs[reg];
@@ -728,7 +687,7 @@ static void emulate_load_store_microMIPS(struct pt_regs *regs,
if (reg == 31)
goto sigbus;
- if (!access_ok(addr, 16))
+ if (user && !access_ok(addr, 16))
goto sigbus;
LoadDW(addr, value, res);
@@ -751,7 +710,7 @@ static void emulate_load_store_microMIPS(struct pt_regs *regs,
if (reg == 31)
goto sigbus;
- if (!access_ok(addr, 16))
+ if (user && !access_ok(addr, 16))
goto sigbus;
value = regs->regs[reg];
@@ -774,10 +733,10 @@ static void emulate_load_store_microMIPS(struct pt_regs *regs,
if ((rvar > 9) || !reg)
goto sigill;
if (reg & 0x10) {
- if (!access_ok(addr, 4 * (rvar + 1)))
+ if (user && !access_ok(addr, 4 * (rvar + 1)))
goto sigbus;
} else {
- if (!access_ok(addr, 4 * rvar))
+ if (user && !access_ok(addr, 4 * rvar))
goto sigbus;
}
if (rvar == 9)
@@ -810,10 +769,10 @@ static void emulate_load_store_microMIPS(struct pt_regs *regs,
if ((rvar > 9) || !reg)
goto sigill;
if (reg & 0x10) {
- if (!access_ok(addr, 4 * (rvar + 1)))
+ if (user && !access_ok(addr, 4 * (rvar + 1)))
goto sigbus;
} else {
- if (!access_ok(addr, 4 * rvar))
+ if (user && !access_ok(addr, 4 * rvar))
goto sigbus;
}
if (rvar == 9)
@@ -847,10 +806,10 @@ static void emulate_load_store_microMIPS(struct pt_regs *regs,
if ((rvar > 9) || !reg)
goto sigill;
if (reg & 0x10) {
- if (!access_ok(addr, 8 * (rvar + 1)))
+ if (user && !access_ok(addr, 8 * (rvar + 1)))
goto sigbus;
} else {
- if (!access_ok(addr, 8 * rvar))
+ if (user && !access_ok(addr, 8 * rvar))
goto sigbus;
}
if (rvar == 9)
@@ -888,10 +847,10 @@ static void emulate_load_store_microMIPS(struct pt_regs *regs,
if ((rvar > 9) || !reg)
goto sigill;
if (reg & 0x10) {
- if (!access_ok(addr, 8 * (rvar + 1)))
+ if (user && !access_ok(addr, 8 * (rvar + 1)))
goto sigbus;
} else {
- if (!access_ok(addr, 8 * rvar))
+ if (user && !access_ok(addr, 8 * rvar))
goto sigbus;
}
if (rvar == 9)
@@ -1010,7 +969,7 @@ static void emulate_load_store_microMIPS(struct pt_regs *regs,
case mm_lwm16_op:
reg = insn.mm16_m_format.rlist;
rvar = reg + 1;
- if (!access_ok(addr, 4 * rvar))
+ if (user && !access_ok(addr, 4 * rvar))
goto sigbus;
for (i = 16; rvar; rvar--, i++) {
@@ -1030,7 +989,7 @@ static void emulate_load_store_microMIPS(struct pt_regs *regs,
case mm_swm16_op:
reg = insn.mm16_m_format.rlist;
rvar = reg + 1;
- if (!access_ok(addr, 4 * rvar))
+ if (user && !access_ok(addr, 4 * rvar))
goto sigbus;
for (i = 16; rvar; rvar--, i++) {
@@ -1084,7 +1043,7 @@ static void emulate_load_store_microMIPS(struct pt_regs *regs,
}
loadHW:
- if (!access_ok(addr, 2))
+ if (user && !access_ok(addr, 2))
goto sigbus;
LoadHW(addr, value, res);
@@ -1094,7 +1053,7 @@ static void emulate_load_store_microMIPS(struct pt_regs *regs,
goto success;
loadHWU:
- if (!access_ok(addr, 2))
+ if (user && !access_ok(addr, 2))
goto sigbus;
LoadHWU(addr, value, res);
@@ -1104,7 +1063,7 @@ static void emulate_load_store_microMIPS(struct pt_regs *regs,
goto success;
loadW:
- if (!access_ok(addr, 4))
+ if (user && !access_ok(addr, 4))
goto sigbus;
LoadW(addr, value, res);
@@ -1122,7 +1081,7 @@ static void emulate_load_store_microMIPS(struct pt_regs *regs,
* would blow up, so for now we don't handle unaligned 64-bit
* instructions on 32-bit kernels.
*/
- if (!access_ok(addr, 4))
+ if (user && !access_ok(addr, 4))
goto sigbus;
LoadWU(addr, value, res);
@@ -1144,7 +1103,7 @@ static void emulate_load_store_microMIPS(struct pt_regs *regs,
* would blow up, so for now we don't handle unaligned 64-bit
* instructions on 32-bit kernels.
*/
- if (!access_ok(addr, 8))
+ if (user && !access_ok(addr, 8))
goto sigbus;
LoadDW(addr, value, res);
@@ -1158,7 +1117,7 @@ static void emulate_load_store_microMIPS(struct pt_regs *regs,
goto sigill;
storeHW:
- if (!access_ok(addr, 2))
+ if (user && !access_ok(addr, 2))
goto sigbus;
value = regs->regs[reg];
@@ -1168,7 +1127,7 @@ static void emulate_load_store_microMIPS(struct pt_regs *regs,
goto success;
storeW:
- if (!access_ok(addr, 4))
+ if (user && !access_ok(addr, 4))
goto sigbus;
value = regs->regs[reg];
@@ -1186,7 +1145,7 @@ static void emulate_load_store_microMIPS(struct pt_regs *regs,
* would blow up, so for now we don't handle unaligned 64-bit
* instructions on 32-bit kernels.
*/
- if (!access_ok(addr, 8))
+ if (user && !access_ok(addr, 8))
goto sigbus;
value = regs->regs[reg];
@@ -1243,6 +1202,7 @@ static void emulate_load_store_MIPS16e(struct pt_regs *regs, void __user * addr)
union mips16e_instruction mips16inst, oldinst;
unsigned int opcode;
int extended = 0;
+ bool user = user_mode(regs);
origpc = regs->cp0_epc;
orig31 = regs->regs[31];
@@ -1344,7 +1304,7 @@ static void emulate_load_store_MIPS16e(struct pt_regs *regs, void __user * addr)
goto sigbus;
case MIPS16e_lh_op:
- if (!access_ok(addr, 2))
+ if (user && !access_ok(addr, 2))
goto sigbus;
LoadHW(addr, value, res);
@@ -1355,7 +1315,7 @@ static void emulate_load_store_MIPS16e(struct pt_regs *regs, void __user * addr)
break;
case MIPS16e_lhu_op:
- if (!access_ok(addr, 2))
+ if (user && !access_ok(addr, 2))
goto sigbus;
LoadHWU(addr, value, res);
@@ -1368,7 +1328,7 @@ static void emulate_load_store_MIPS16e(struct pt_regs *regs, void __user * addr)
case MIPS16e_lw_op:
case MIPS16e_lwpc_op:
case MIPS16e_lwsp_op:
- if (!access_ok(addr, 4))
+ if (user && !access_ok(addr, 4))
goto sigbus;
LoadW(addr, value, res);
@@ -1387,7 +1347,7 @@ static void emulate_load_store_MIPS16e(struct pt_regs *regs, void __user * addr)
* would blow up, so for now we don't handle unaligned 64-bit
* instructions on 32-bit kernels.
*/
- if (!access_ok(addr, 4))
+ if (user && !access_ok(addr, 4))
goto sigbus;
LoadWU(addr, value, res);
@@ -1411,7 +1371,7 @@ static void emulate_load_store_MIPS16e(struct pt_regs *regs, void __user * addr)
* would blow up, so for now we don't handle unaligned 64-bit
* instructions on 32-bit kernels.
*/
- if (!access_ok(addr, 8))
+ if (user && !access_ok(addr, 8))
goto sigbus;
LoadDW(addr, value, res);
@@ -1426,7 +1386,7 @@ static void emulate_load_store_MIPS16e(struct pt_regs *regs, void __user * addr)
goto sigill;
case MIPS16e_sh_op:
- if (!access_ok(addr, 2))
+ if (user && !access_ok(addr, 2))
goto sigbus;
MIPS16e_compute_return_epc(regs, &oldinst);
@@ -1439,7 +1399,7 @@ static void emulate_load_store_MIPS16e(struct pt_regs *regs, void __user * addr)
case MIPS16e_sw_op:
case MIPS16e_swsp_op:
case MIPS16e_i8_op: /* actually - MIPS16e_swrasp_func */
- if (!access_ok(addr, 4))
+ if (user && !access_ok(addr, 4))
goto sigbus;
MIPS16e_compute_return_epc(regs, &oldinst);
@@ -1459,7 +1419,7 @@ static void emulate_load_store_MIPS16e(struct pt_regs *regs, void __user * addr)
* would blow up, so for now we don't handle unaligned 64-bit
* instructions on 32-bit kernels.
*/
- if (!access_ok(addr, 8))
+ if (user && !access_ok(addr, 8))
goto sigbus;
MIPS16e_compute_return_epc(regs, &oldinst);
@@ -1516,7 +1476,6 @@ asmlinkage void do_ade(struct pt_regs *regs)
{
enum ctx_state prev_state;
unsigned int __user *pc;
- mm_segment_t seg;
prev_state = exception_enter();
perf_sw_event(PERF_COUNT_SW_ALIGNMENT_FAULTS,
@@ -1551,24 +1510,14 @@ asmlinkage void do_ade(struct pt_regs *regs)
show_registers(regs);
if (cpu_has_mmips) {
- seg = get_fs();
- if (!user_mode(regs))
- set_fs(KERNEL_DS);
emulate_load_store_microMIPS(regs,
(void __user *)regs->cp0_badvaddr);
- set_fs(seg);
-
return;
}
if (cpu_has_mips16) {
- seg = get_fs();
- if (!user_mode(regs))
- set_fs(KERNEL_DS);
emulate_load_store_MIPS16e(regs,
(void __user *)regs->cp0_badvaddr);
- set_fs(seg);
-
return;
}
@@ -1579,11 +1528,7 @@ asmlinkage void do_ade(struct pt_regs *regs)
show_registers(regs);
pc = (unsigned int __user *)exception_epc(regs);
- seg = get_fs();
- if (!user_mode(regs))
- set_fs(KERNEL_DS);
emulate_load_store_insn(regs, (void __user *)regs->cp0_badvaddr, pc);
- set_fs(seg);
return;
--
2.29.2
All get_fs/set_fs calls in MIPS code are gone, so remove implementation
of it. With the clear separation of user/kernel space access we no
longer need the EVA special handling, so get rid of that, too.
Signed-off-by: Thomas Bogendoerfer <[email protected]>
---
arch/mips/Kconfig | 1 -
arch/mips/include/asm/processor.h | 4 -
arch/mips/include/asm/thread_info.h | 6 -
arch/mips/include/asm/uaccess.h | 426 ++++++++++------------------
arch/mips/kernel/asm-offsets.c | 1 -
arch/mips/kernel/process.c | 2 -
arch/mips/kernel/scall32-o32.S | 4 +-
arch/mips/lib/memcpy.S | 28 +-
arch/mips/lib/memset.S | 3 -
arch/mips/lib/strncpy_user.S | 48 +---
arch/mips/lib/strnlen_user.S | 44 +--
11 files changed, 190 insertions(+), 377 deletions(-)
diff --git a/arch/mips/Kconfig b/arch/mips/Kconfig
index b72458215d20..70faa0686444 100644
--- a/arch/mips/Kconfig
+++ b/arch/mips/Kconfig
@@ -93,7 +93,6 @@ config MIPS
select PERF_USE_VMALLOC
select PCI_MSI_ARCH_FALLBACKS if PCI_MSI
select RTC_LIB
- select SET_FS
select SYSCTL_EXCEPTION_TRACE
select VIRT_TO_BUS
select ARCH_HAS_ELFCORE_COMPAT
diff --git a/arch/mips/include/asm/processor.h b/arch/mips/include/asm/processor.h
index 8e69e0a35ee9..0c3550c82b72 100644
--- a/arch/mips/include/asm/processor.h
+++ b/arch/mips/include/asm/processor.h
@@ -221,10 +221,6 @@ struct nlm_cop2_state {
#define COP2_INIT
#endif
-typedef struct {
- unsigned long seg;
-} mm_segment_t;
-
#ifdef CONFIG_CPU_HAS_MSA
# define ARCH_MIN_TASKALIGN 16
# define FPU_ALIGN __aligned(16)
diff --git a/arch/mips/include/asm/thread_info.h b/arch/mips/include/asm/thread_info.h
index e2c352da3877..0b17aaa9e012 100644
--- a/arch/mips/include/asm/thread_info.h
+++ b/arch/mips/include/asm/thread_info.h
@@ -28,11 +28,6 @@ struct thread_info {
unsigned long tp_value; /* thread pointer */
__u32 cpu; /* current CPU */
int preempt_count; /* 0 => preemptable, <0 => BUG */
- mm_segment_t addr_limit; /*
- * thread address space limit:
- * 0x7fffffff for user-thead
- * 0xffffffff for kernel-thread
- */
struct pt_regs *regs;
long syscall; /* syscall number */
};
@@ -46,7 +41,6 @@ struct thread_info {
.flags = _TIF_FIXADE, \
.cpu = 0, \
.preempt_count = INIT_PREEMPT_COUNT, \
- .addr_limit = KERNEL_DS, \
}
/*
diff --git a/arch/mips/include/asm/uaccess.h b/arch/mips/include/asm/uaccess.h
index c5cab0b8f902..d341228b907a 100644
--- a/arch/mips/include/asm/uaccess.h
+++ b/arch/mips/include/asm/uaccess.h
@@ -16,13 +16,6 @@
#include <asm/asm-eva.h>
#include <asm/extable.h>
-/*
- * The fs value determines whether argument validity checking should be
- * performed or not. If get_fs() == USER_DS, checking is performed, with
- * get_fs() == KERNEL_DS, checking is bypassed.
- *
- * For historical reasons, these macros are grossly misnamed.
- */
#ifdef CONFIG_32BIT
#define __UA_LIMIT 0x80000000UL
@@ -49,38 +42,6 @@ extern u64 __ua_limit;
#endif /* CONFIG_64BIT */
-/*
- * USER_DS is a bitmask that has the bits set that may not be set in a valid
- * userspace address. Note that we limit 32-bit userspace to 0x7fff8000 but
- * the arithmetic we're doing only works if the limit is a power of two, so
- * we use 0x80000000 here on 32-bit kernels. If a process passes an invalid
- * address in this range it's the process's problem, not ours :-)
- */
-
-#define KERNEL_DS ((mm_segment_t) { 0UL })
-#define USER_DS ((mm_segment_t) { __UA_LIMIT })
-
-#define get_fs() (current_thread_info()->addr_limit)
-#define set_fs(x) (current_thread_info()->addr_limit = (x))
-
-#define uaccess_kernel() (get_fs().seg == KERNEL_DS.seg)
-
-/*
- * eva_kernel_access() - determine whether kernel memory access on an EVA system
- *
- * Determines whether memory accesses should be performed to kernel memory
- * on a system using Extended Virtual Addressing (EVA).
- *
- * Return: true if a kernel memory access on an EVA system, else false.
- */
-static inline bool eva_kernel_access(void)
-{
- if (!IS_ENABLED(CONFIG_EVA))
- return false;
-
- return uaccess_kernel();
-}
-
/*
* Is a address valid? This does a straightforward calculation rather
* than tests.
@@ -118,7 +79,7 @@ static inline bool eva_kernel_access(void)
static inline int __access_ok(const void __user *p, unsigned long size)
{
unsigned long addr = (unsigned long)p;
- return (get_fs().seg & (addr | (addr + size) | __ua_size(size))) == 0;
+ return (__UA_LIMIT & (addr | (addr + size) | __ua_size(size))) == 0;
}
#define access_ok(addr, size) \
@@ -215,43 +176,6 @@ static inline int __access_ok(const void __user *p, unsigned long size)
struct __large_struct { unsigned long buf[100]; };
#define __m(x) (*(struct __large_struct __user *)(x))
-/*
- * Yuck. We need two variants, one for 64bit operation and one
- * for 32 bit mode and old iron.
- */
-#ifndef CONFIG_EVA
-#define __get_kernel_common(val, size, ptr) __get_user_common(val, size, ptr)
-#else
-/*
- * Kernel specific functions for EVA. We need to use normal load instructions
- * to read data from kernel when operating in EVA mode. We use these macros to
- * avoid redefining __get_user_asm for EVA.
- */
-#undef _loadd
-#undef _loadw
-#undef _loadh
-#undef _loadb
-#ifdef CONFIG_32BIT
-#define _loadd _loadw
-#else
-#define _loadd(reg, addr) "ld " reg ", " addr
-#endif
-#define _loadw(reg, addr) "lw " reg ", " addr
-#define _loadh(reg, addr) "lh " reg ", " addr
-#define _loadb(reg, addr) "lb " reg ", " addr
-
-#define __get_kernel_common(val, size, ptr) \
-do { \
- switch (size) { \
- case 1: __get_data_asm(val, _loadb, ptr); break; \
- case 2: __get_data_asm(val, _loadh, ptr); break; \
- case 4: __get_data_asm(val, _loadw, ptr); break; \
- case 8: __GET_DW(val, _loadd, ptr); break; \
- default: __get_user_unknown(); break; \
- } \
-} while (0)
-#endif
-
#ifdef CONFIG_32BIT
#define __GET_DW(val, insn, ptr) __get_data_asm_ll32(val, insn, ptr)
#endif
@@ -276,12 +200,9 @@ do { \
({ \
int __gu_err; \
\
- if (eva_kernel_access()) { \
- __get_kernel_common((x), size, ptr); \
- } else { \
- __chk_user_ptr(ptr); \
- __get_user_common((x), size, ptr); \
- } \
+ __chk_user_ptr(ptr); \
+ __get_user_common((x), size, ptr); \
+ \
__gu_err; \
})
@@ -291,11 +212,8 @@ do { \
const __typeof__(*(ptr)) __user * __gu_ptr = (ptr); \
\
might_fault(); \
- if (likely(access_ok( __gu_ptr, size))) { \
- if (eva_kernel_access()) \
- __get_kernel_common((x), size, __gu_ptr); \
- else \
- __get_user_common((x), size, __gu_ptr); \
+ if (likely(access_ok(__gu_ptr, size))) { \
+ __get_user_common((x), size, __gu_ptr); \
} else \
(x) = 0; \
\
@@ -361,46 +279,31 @@ do { \
do { \
int __gu_err; \
\
- __get_kernel_common(*((type *)(dst)), sizeof(type), \
- (__force type *)(src)); \
+ switch (sizeof(type)) { \
+ case 1: \
+ __get_data_asm(*(type *)(dst), kernel_lb, \
+ (__force type *)(src)); \
+ break; \
+ case 2: \
+ __get_data_asm(*(type *)(dst), kernel_lh, \
+ (__force type *)(src)); \
+ break; \
+ case 4: \
+ __get_data_asm(*(type *)(dst), kernel_lw, \
+ (__force type *)(src)); \
+ break; \
+ case 8: \
+ __GET_DW(*(type *)(dst), kernel_ld, \
+ (__force type *)(src)); \
+ break; \
+ default: \
+ __get_user_unknown(); \
+ break; \
+ } \
if (unlikely(__gu_err)) \
goto err_label; \
} while (0)
-#ifndef CONFIG_EVA
-#define __put_kernel_common(ptr, size) __put_user_common(ptr, size)
-#else
-/*
- * Kernel specific functions for EVA. We need to use normal load instructions
- * to read data from kernel when operating in EVA mode. We use these macros to
- * avoid redefining __get_data_asm for EVA.
- */
-#undef _stored
-#undef _storew
-#undef _storeh
-#undef _storeb
-#ifdef CONFIG_32BIT
-#define _stored _storew
-#else
-#define _stored(reg, addr) "ld " reg ", " addr
-#endif
-
-#define _storew(reg, addr) "sw " reg ", " addr
-#define _storeh(reg, addr) "sh " reg ", " addr
-#define _storeb(reg, addr) "sb " reg ", " addr
-
-#define __put_kernel_common(ptr, size) \
-do { \
- switch (size) { \
- case 1: __put_data_asm(_storeb, ptr); break; \
- case 2: __put_data_asm(_storeh, ptr); break; \
- case 4: __put_data_asm(_storew, ptr); break; \
- case 8: __PUT_DW(_stored, ptr); break; \
- default: __put_user_unknown(); break; \
- } \
-} while(0)
-#endif
-
/*
* Yuck. We need two variants, one for 64bit operation and one
* for 32 bit mode and old iron.
@@ -429,12 +332,9 @@ do { \
int __pu_err = 0; \
\
__pu_val = (x); \
- if (eva_kernel_access()) { \
- __put_kernel_common(ptr, size); \
- } else { \
- __chk_user_ptr(ptr); \
- __put_user_common(ptr, size); \
- } \
+ __chk_user_ptr(ptr); \
+ __put_user_common(ptr, size); \
+ \
__pu_err; \
})
@@ -445,11 +345,8 @@ do { \
int __pu_err = -EFAULT; \
\
might_fault(); \
- if (likely(access_ok( __pu_addr, size))) { \
- if (eva_kernel_access()) \
- __put_kernel_common(__pu_addr, size); \
- else \
- __put_user_common(__pu_addr, size); \
+ if (likely(access_ok(__pu_addr, size))) { \
+ __put_user_common(__pu_addr, size); \
} \
\
__pu_err; \
@@ -501,7 +398,23 @@ do { \
int __pu_err = 0; \
\
__pu_val = *(__force type *)(src); \
- __put_kernel_common(((type *)(dst)), sizeof(type)); \
+ switch (sizeof(type)) { \
+ case 1: \
+ __put_data_asm(kernel_sb, (type *)(dst)); \
+ break; \
+ case 2: \
+ __put_data_asm(kernel_sh, (type *)(dst)); \
+ break; \
+ case 4: \
+ __put_data_asm(kernel_sw, (type *)(dst)) \
+ break; \
+ case 8: \
+ __PUT_DW(kernel_sd, (type *)(dst)); \
+ break; \
+ default: \
+ __put_user_unknown(); \
+ break; \
+ } \
if (unlikely(__pu_err)) \
goto err_label; \
} while (0)
@@ -529,8 +442,6 @@ do { \
#define DADDI_SCRATCH "$0"
#endif
-extern size_t __copy_user(void *__to, const void *__from, size_t __n);
-
#define __invoke_copy_from(func, to, from, n) \
({ \
register void *__cu_to_r __asm__("$4"); \
@@ -554,99 +465,85 @@ extern size_t __copy_user(void *__to, const void *__from, size_t __n);
__cu_len_r; \
})
-#define __invoke_copy_to(func, to, from, n) \
-({ \
- register void __user *__cu_to_r __asm__("$4"); \
- register const void *__cu_from_r __asm__("$5"); \
- register long __cu_len_r __asm__("$6"); \
- \
- __cu_to_r = (to); \
- __cu_from_r = (from); \
- __cu_len_r = (n); \
- __asm__ __volatile__( \
- __MODULE_JAL(func) \
- : "+r" (__cu_to_r), "+r" (__cu_from_r), "+r" (__cu_len_r) \
- : \
- : "$8", "$9", "$10", "$11", "$12", "$14", "$15", "$24", "$31", \
- DADDI_SCRATCH, "memory"); \
- __cu_len_r; \
-})
-
-#define __invoke_copy_from_kernel(to, from, n) \
- __invoke_copy_from(__copy_user, to, from, n)
-
-#define __invoke_copy_to_kernel(to, from, n) \
- __invoke_copy_to(__copy_user, to, from, n)
-
-#define ___invoke_copy_in_kernel(to, from, n) \
- __invoke_copy_from(__copy_user, to, from, n)
-
-#ifndef CONFIG_EVA
-#define __invoke_copy_from_user(to, from, n) \
- __invoke_copy_from(__copy_user, to, from, n)
-
-#define __invoke_copy_to_user(to, from, n) \
- __invoke_copy_to(__copy_user, to, from, n)
-
-#define ___invoke_copy_in_user(to, from, n) \
- __invoke_copy_from(__copy_user, to, from, n)
-
-#else
-
-/* EVA specific functions */
-
-extern size_t __copy_from_user_eva(void *__to, const void *__from,
- size_t __n);
-extern size_t __copy_to_user_eva(void *__to, const void *__from,
- size_t __n);
-extern size_t __copy_in_user_eva(void *__to, const void *__from, size_t __n);
-
-/*
- * Source or destination address is in userland. We need to go through
- * the TLB
- */
-#define __invoke_copy_from_user(to, from, n) \
- __invoke_copy_from(__copy_from_user_eva, to, from, n)
-
-#define __invoke_copy_to_user(to, from, n) \
- __invoke_copy_to(__copy_to_user_eva, to, from, n)
-
-#define ___invoke_copy_in_user(to, from, n) \
- __invoke_copy_from(__copy_in_user_eva, to, from, n)
-
-#endif /* CONFIG_EVA */
+extern size_t __raw_copy_from_user(void *__to, const void *__from, size_t __n);
+extern size_t __raw_copy_to_user(void *__to, const void *__from, size_t __n);
+extern size_t __raw_copy_in_user(void *__to, const void *__from, size_t __n);
static inline unsigned long
-raw_copy_to_user(void __user *to, const void *from, unsigned long n)
+raw_copy_from_user(void *to, const void __user *from, unsigned long n)
{
- if (eva_kernel_access())
- return __invoke_copy_to_kernel(to, from, n);
- else
- return __invoke_copy_to_user(to, from, n);
+ register void *__cu_to_r __asm__("$4");
+ register const void __user *__cu_from_r __asm__("$5");
+ register long __cu_len_r __asm__("$6");
+
+ __cu_to_r = to;
+ __cu_from_r = from;
+ __cu_len_r = n;
+
+ __asm__ __volatile__(
+ ".set\tnoreorder\n\t"
+ __MODULE_JAL(__raw_copy_from_user)
+ ".set\tnoat\n\t"
+ __UA_ADDU "\t$1, %1, %2\n\t"
+ ".set\tat\n\t"
+ ".set\treorder"
+ : "+r" (__cu_to_r), "+r" (__cu_from_r), "+r" (__cu_len_r)
+ :
+ : "$8", "$9", "$10", "$11", "$12", "$14", "$15", "$24", "$31",
+ DADDI_SCRATCH, "memory");
+
+ return __cu_len_r;
}
static inline unsigned long
-raw_copy_from_user(void *to, const void __user *from, unsigned long n)
+raw_copy_to_user(void __user *to, const void *from, unsigned long n)
{
- if (eva_kernel_access())
- return __invoke_copy_from_kernel(to, from, n);
- else
- return __invoke_copy_from_user(to, from, n);
+ register void __user *__cu_to_r __asm__("$4");
+ register const void *__cu_from_r __asm__("$5");
+ register long __cu_len_r __asm__("$6");
+
+ __cu_to_r = (to);
+ __cu_from_r = (from);
+ __cu_len_r = (n);
+
+ __asm__ __volatile__(
+ __MODULE_JAL(__raw_copy_to_user)
+ : "+r" (__cu_to_r), "+r" (__cu_from_r), "+r" (__cu_len_r)
+ :
+ : "$8", "$9", "$10", "$11", "$12", "$14", "$15", "$24", "$31",
+ DADDI_SCRATCH, "memory");
+
+ return __cu_len_r;
}
#define INLINE_COPY_FROM_USER
#define INLINE_COPY_TO_USER
static inline unsigned long
-raw_copy_in_user(void __user*to, const void __user *from, unsigned long n)
+raw_copy_in_user(void __user *to, const void __user *from, unsigned long n)
{
- if (eva_kernel_access())
- return ___invoke_copy_in_kernel(to, from, n);
- else
- return ___invoke_copy_in_user(to, from, n);
+ register void __user *__cu_to_r __asm__("$4");
+ register const void __user *__cu_from_r __asm__("$5");
+ register long __cu_len_r __asm__("$6");
+
+ __cu_to_r = to;
+ __cu_from_r = from;
+ __cu_len_r = n;
+
+ __asm__ __volatile__(
+ ".set\tnoreorder\n\t"
+ __MODULE_JAL(__raw_copy_in_user)
+ ".set\tnoat\n\t"
+ __UA_ADDU "\t$1, %1, %2\n\t"
+ ".set\tat\n\t"
+ ".set\treorder"
+ : "+r" (__cu_to_r), "+r" (__cu_from_r), "+r" (__cu_len_r)
+ :
+ : "$8", "$9", "$10", "$11", "$12", "$14", "$15", "$24", "$31",
+ DADDI_SCRATCH, "memory");
+ return __cu_len_r;
}
-extern __kernel_size_t __bzero_kernel(void __user *addr, __kernel_size_t size);
extern __kernel_size_t __bzero(void __user *addr, __kernel_size_t size);
/*
@@ -672,28 +569,16 @@ __clear_user(void __user *addr, __kernel_size_t size)
#define bzero_clobbers "$4", "$5", "$6", __UA_t0, __UA_t1, "$31"
#endif /* CONFIG_CPU_MICROMIPS */
- if (eva_kernel_access()) {
- __asm__ __volatile__(
- "move\t$4, %1\n\t"
- "move\t$5, $0\n\t"
- "move\t$6, %2\n\t"
- __MODULE_JAL(__bzero_kernel)
- "move\t%0, $6"
- : "=r" (res)
- : "r" (addr), "r" (size)
- : bzero_clobbers);
- } else {
- might_fault();
- __asm__ __volatile__(
- "move\t$4, %1\n\t"
- "move\t$5, $0\n\t"
- "move\t$6, %2\n\t"
- __MODULE_JAL(__bzero)
- "move\t%0, $6"
- : "=r" (res)
- : "r" (addr), "r" (size)
- : bzero_clobbers);
- }
+ might_fault();
+ __asm__ __volatile__(
+ "move\t$4, %1\n\t"
+ "move\t$5, $0\n\t"
+ "move\t$6, %2\n\t"
+ __MODULE_JAL(__bzero)
+ "move\t%0, $6"
+ : "=r" (res)
+ : "r" (addr), "r" (size)
+ : bzero_clobbers);
return res;
}
@@ -707,7 +592,6 @@ __clear_user(void __user *addr, __kernel_size_t size)
__cl_size; \
})
-extern long __strncpy_from_kernel_asm(char *__to, const char __user *__from, long __len);
extern long __strncpy_from_user_asm(char *__to, const char __user *__from, long __len);
/*
@@ -733,33 +617,23 @@ strncpy_from_user(char *__to, const char __user *__from, long __len)
{
long res;
- if (eva_kernel_access()) {
- __asm__ __volatile__(
- "move\t$4, %1\n\t"
- "move\t$5, %2\n\t"
- "move\t$6, %3\n\t"
- __MODULE_JAL(__strncpy_from_kernel_asm)
- "move\t%0, $2"
- : "=r" (res)
- : "r" (__to), "r" (__from), "r" (__len)
- : "$2", "$3", "$4", "$5", "$6", __UA_t0, "$31", "memory");
- } else {
- might_fault();
- __asm__ __volatile__(
- "move\t$4, %1\n\t"
- "move\t$5, %2\n\t"
- "move\t$6, %3\n\t"
- __MODULE_JAL(__strncpy_from_user_asm)
- "move\t%0, $2"
- : "=r" (res)
- : "r" (__to), "r" (__from), "r" (__len)
- : "$2", "$3", "$4", "$5", "$6", __UA_t0, "$31", "memory");
- }
+ if (!access_ok(__from, __len))
+ return -EFAULT;
+
+ might_fault();
+ __asm__ __volatile__(
+ "move\t$4, %1\n\t"
+ "move\t$5, %2\n\t"
+ "move\t$6, %3\n\t"
+ __MODULE_JAL(__strncpy_from_user_asm)
+ "move\t%0, $2"
+ : "=r" (res)
+ : "r" (__to), "r" (__from), "r" (__len)
+ : "$2", "$3", "$4", "$5", "$6", __UA_t0, "$31", "memory");
return res;
}
-extern long __strnlen_kernel_asm(const char __user *s, long n);
extern long __strnlen_user_asm(const char __user *s, long n);
/*
@@ -779,26 +653,18 @@ static inline long strnlen_user(const char __user *s, long n)
{
long res;
+ if (!access_ok(s, n))
+ return -0;
+
might_fault();
- if (eva_kernel_access()) {
- __asm__ __volatile__(
- "move\t$4, %1\n\t"
- "move\t$5, %2\n\t"
- __MODULE_JAL(__strnlen_kernel_asm)
- "move\t%0, $2"
- : "=r" (res)
- : "r" (s), "r" (n)
- : "$2", "$4", "$5", __UA_t0, "$31");
- } else {
- __asm__ __volatile__(
- "move\t$4, %1\n\t"
- "move\t$5, %2\n\t"
- __MODULE_JAL(__strnlen_user_asm)
- "move\t%0, $2"
- : "=r" (res)
- : "r" (s), "r" (n)
- : "$2", "$4", "$5", __UA_t0, "$31");
- }
+ __asm__ __volatile__(
+ "move\t$4, %1\n\t"
+ "move\t$5, %2\n\t"
+ __MODULE_JAL(__strnlen_user_asm)
+ "move\t%0, $2"
+ : "=r" (res)
+ : "r" (s), "r" (n)
+ : "$2", "$4", "$5", __UA_t0, "$31");
return res;
}
diff --git a/arch/mips/kernel/asm-offsets.c b/arch/mips/kernel/asm-offsets.c
index aebfda81120a..5735b2cd6f2a 100644
--- a/arch/mips/kernel/asm-offsets.c
+++ b/arch/mips/kernel/asm-offsets.c
@@ -98,7 +98,6 @@ void output_thread_info_defines(void)
OFFSET(TI_TP_VALUE, thread_info, tp_value);
OFFSET(TI_CPU, thread_info, cpu);
OFFSET(TI_PRE_COUNT, thread_info, preempt_count);
- OFFSET(TI_ADDR_LIMIT, thread_info, addr_limit);
OFFSET(TI_REGS, thread_info, regs);
DEFINE(_THREAD_SIZE, THREAD_SIZE);
DEFINE(_THREAD_MASK, THREAD_MASK);
diff --git a/arch/mips/kernel/process.c b/arch/mips/kernel/process.c
index 7efa0d1a4c2b..bff080db0294 100644
--- a/arch/mips/kernel/process.c
+++ b/arch/mips/kernel/process.c
@@ -124,7 +124,6 @@ int copy_thread(unsigned long clone_flags, unsigned long usp,
/* kernel thread */
unsigned long status = p->thread.cp0_status;
memset(childregs, 0, sizeof(struct pt_regs));
- ti->addr_limit = KERNEL_DS;
p->thread.reg16 = usp; /* fn */
p->thread.reg17 = kthread_arg;
p->thread.reg29 = childksp;
@@ -145,7 +144,6 @@ int copy_thread(unsigned long clone_flags, unsigned long usp,
childregs->regs[2] = 0; /* Child gets zero as return value */
if (usp)
childregs->regs[29] = usp;
- ti->addr_limit = USER_DS;
p->thread.reg29 = (unsigned long) childregs;
p->thread.reg31 = (unsigned long) ret_from_fork;
diff --git a/arch/mips/kernel/scall32-o32.S b/arch/mips/kernel/scall32-o32.S
index 84e8624e83a2..b1b2e106f711 100644
--- a/arch/mips/kernel/scall32-o32.S
+++ b/arch/mips/kernel/scall32-o32.S
@@ -48,10 +48,8 @@ NESTED(handle_sys, PT_SIZE, sp)
* We intentionally keep the kernel stack a little below the top of
* userspace so we don't have to do a slower byte accurate check here.
*/
- lw t5, TI_ADDR_LIMIT($28)
addu t4, t0, 32
- and t5, t4
- bltz t5, bad_stack # -> sp is bad
+ bltz t4, bad_stack # -> sp is bad
/*
* Ok, copy the args from the luser stack to the kernel stack.
diff --git a/arch/mips/lib/memcpy.S b/arch/mips/lib/memcpy.S
index 88065ee433cd..e19fb98b5d38 100644
--- a/arch/mips/lib/memcpy.S
+++ b/arch/mips/lib/memcpy.S
@@ -661,8 +661,14 @@ LEAF(memcpy) /* a0=dst a1=src a2=len */
EXPORT_SYMBOL(memcpy)
move v0, dst /* return value */
.L__memcpy:
-FEXPORT(__copy_user)
-EXPORT_SYMBOL(__copy_user)
+#ifndef CONFIG_EVA
+FEXPORT(__raw_copy_from_user)
+EXPORT_SYMBOL(__raw_copy_from_user)
+FEXPORT(__raw_copy_to_user)
+EXPORT_SYMBOL(__raw_copy_to_user)
+FEXPORT(__raw_copy_in_user)
+EXPORT_SYMBOL(__raw_copy_in_user)
+#endif
/* Legacy Mode, user <-> user */
__BUILD_COPY_USER LEGACY_MODE USEROP USEROP
@@ -681,10 +687,10 @@ EXPORT_SYMBOL(__copy_user)
* __copy_from_user (EVA)
*/
-LEAF(__copy_from_user_eva)
-EXPORT_SYMBOL(__copy_from_user_eva)
+LEAF(__raw_copy_from_user)
+EXPORT_SYMBOL(__raw_copy_from_user)
__BUILD_COPY_USER EVA_MODE USEROP KERNELOP
-END(__copy_from_user_eva)
+END(__raw_copy_from_user)
@@ -692,18 +698,18 @@ END(__copy_from_user_eva)
* __copy_to_user (EVA)
*/
-LEAF(__copy_to_user_eva)
-EXPORT_SYMBOL(__copy_to_user_eva)
+LEAF(__raw_copy_to_user)
+EXPORT_SYMBOL(__raw_copy_to_user)
__BUILD_COPY_USER EVA_MODE KERNELOP USEROP
-END(__copy_to_user_eva)
+END(__raw_copy_to_user)
/*
* __copy_in_user (EVA)
*/
-LEAF(__copy_in_user_eva)
-EXPORT_SYMBOL(__copy_in_user_eva)
+LEAF(__raw_copy_in_user)
+EXPORT_SYMBOL(__raw_copy_in_user)
__BUILD_COPY_USER EVA_MODE USEROP USEROP
-END(__copy_in_user_eva)
+END(__raw_copy_in_user)
#endif
diff --git a/arch/mips/lib/memset.S b/arch/mips/lib/memset.S
index d5449e8a3dfc..b0baa3c79fad 100644
--- a/arch/mips/lib/memset.S
+++ b/arch/mips/lib/memset.S
@@ -314,9 +314,6 @@ EXPORT_SYMBOL(memset)
#ifndef CONFIG_EVA
FEXPORT(__bzero)
EXPORT_SYMBOL(__bzero)
-#else
-FEXPORT(__bzero_kernel)
-EXPORT_SYMBOL(__bzero_kernel)
#endif
__BUILD_BZERO LEGACY_MODE
diff --git a/arch/mips/lib/strncpy_user.S b/arch/mips/lib/strncpy_user.S
index acdff66bd5d2..556acf684d7b 100644
--- a/arch/mips/lib/strncpy_user.S
+++ b/arch/mips/lib/strncpy_user.S
@@ -29,19 +29,17 @@
* it happens at most some bytes of the exceptions handlers will be copied.
*/
- .macro __BUILD_STRNCPY_ASM func
-LEAF(__strncpy_from_\func\()_asm)
- LONG_L v0, TI_ADDR_LIMIT($28) # pointer ok?
- and v0, a1
- bnez v0, .Lfault\@
-
+LEAF(__strncpy_from_user_asm)
move t0, zero
move v1, a1
-.ifeqs "\func","kernel"
-1: EX(lbu, v0, (v1), .Lfault\@)
-.else
-1: EX(lbue, v0, (v1), .Lfault\@)
-.endif
+#ifdef CONFIG_EVA
+ .set push
+ .set eva
+1: EX(lbue, v0, (v1), .Lfault)
+ .set pop
+#else
+1: EX(lbu, v0, (v1), .Lfault)
+#endif
PTR_ADDIU v1, 1
R10KCBARRIER(0(ra))
sb v0, (a0)
@@ -51,35 +49,17 @@ LEAF(__strncpy_from_\func\()_asm)
bne t0, a2, 1b
2: PTR_ADDU v0, a1, t0
xor v0, a1
- bltz v0, .Lfault\@
+ bltz v0, .Lfault
move v0, t0
jr ra # return n
- END(__strncpy_from_\func\()_asm)
+ END(__strncpy_from_user_asm)
-.Lfault\@:
+.Lfault:
li v0, -EFAULT
jr ra
.section __ex_table,"a"
- PTR 1b, .Lfault\@
+ PTR 1b, .Lfault
.previous
- .endm
-
-#ifndef CONFIG_EVA
- /* Set aliases */
- .global __strncpy_from_user_asm
- .set __strncpy_from_user_asm, __strncpy_from_kernel_asm
-EXPORT_SYMBOL(__strncpy_from_user_asm)
-#endif
-
-__BUILD_STRNCPY_ASM kernel
-EXPORT_SYMBOL(__strncpy_from_kernel_asm)
-
-#ifdef CONFIG_EVA
- .set push
- .set eva
-__BUILD_STRNCPY_ASM user
- .set pop
-EXPORT_SYMBOL(__strncpy_from_user_asm)
-#endif
+ EXPORT_SYMBOL(__strncpy_from_user_asm)
diff --git a/arch/mips/lib/strnlen_user.S b/arch/mips/lib/strnlen_user.S
index e1bacf5a3abe..92b63f20ec05 100644
--- a/arch/mips/lib/strnlen_user.S
+++ b/arch/mips/lib/strnlen_user.S
@@ -26,12 +26,7 @@
* bytes. There's nothing secret there. On 64-bit accessing beyond
* the maximum is a tad hairier ...
*/
- .macro __BUILD_STRNLEN_ASM func
-LEAF(__strnlen_\func\()_asm)
- LONG_L v0, TI_ADDR_LIMIT($28) # pointer ok?
- and v0, a0
- bnez v0, .Lfault\@
-
+LEAF(__strnlen_user_asm)
move v0, a0
PTR_ADDU a1, a0 # stop pointer
1:
@@ -40,11 +35,14 @@ LEAF(__strnlen_\func\()_asm)
li AT, 1
#endif
beq v0, a1, 1f # limit reached?
-.ifeqs "\func", "kernel"
- EX(lb, t0, (v0), .Lfault\@)
-.else
- EX(lbe, t0, (v0), .Lfault\@)
-.endif
+#ifdef CONFIG_EVA
+ .set push
+ .set eva
+ EX(lbe, t0, (v0), .Lfault)
+ .set pop
+#else
+ EX(lb, t0, (v0), .Lfault)
+#endif
.set noreorder
bnez t0, 1b
1:
@@ -57,28 +55,10 @@ LEAF(__strnlen_\func\()_asm)
.set reorder
PTR_SUBU v0, a0
jr ra
- END(__strnlen_\func\()_asm)
+ END(__strnlen_user_asm)
-.Lfault\@:
+.Lfault:
move v0, zero
jr ra
- .endm
-
-#ifndef CONFIG_EVA
- /* Set aliases */
- .global __strnlen_user_asm
- .set __strnlen_user_asm, __strnlen_kernel_asm
-EXPORT_SYMBOL(__strnlen_user_asm)
-#endif
-
-__BUILD_STRNLEN_ASM kernel
-EXPORT_SYMBOL(__strnlen_kernel_asm)
-
-#ifdef CONFIG_EVA
- .set push
- .set eva
-__BUILD_STRNLEN_ASM user
- .set pop
-EXPORT_SYMBOL(__strnlen_user_asm)
-#endif
+ EXPORT_SYMBOL(__strnlen_user_asm)
--
2.29.2
On Wed, Mar 31, 2021 at 01:55:58PM +0200, Thomas Bogendoerfer wrote:
> flush_icache_range always does flush kernel address ranges, so no
> need to do the set_fs dance.
>
> Signed-off-by: Thomas Bogendoerfer <[email protected]>
Looks good,
Reviewed-by: Christoph Hellwig <[email protected]>
On Wed, Mar 31, 2021 at 01:55:59PM +0200, Thomas Bogendoerfer wrote:
> Added __get/__put_kernel_nofault as preparation for removing
> get/set_fs.
>
> Signed-off-by: Thomas Bogendoerfer <[email protected]>
Looks good,
Reviewed-by: Christoph Hellwig <[email protected]>
On Wed, Mar 31, 2021 at 01:56:00PM +0200, Thomas Bogendoerfer wrote:
> +#define __get_user_nofault(dst, src, type, err_label) \
> +do { \
> + int __gu_err; \
> + \
> + __get_user_common(*((type *)(dst)), sizeof(type), \
> + (__force type *)(src)); \
> + if (unlikely(__gu_err)) \
> + goto err_label; \
> +} while (0)
> +
> +
> +static inline int __get_addr(unsigned long *a, unsigned long *p, bool user)
> +{
> + if (user)
> + __get_user_nofault(a, p, unsigned long, fault);
> + else
> + __get_kernel_nofault(a, p, unsigned long, fault);
> +
> + return 0;
> +
> +fault:
> + return -EFAULT;
> +}
Why can't these use plain old get_user and get_kernel_nofault?
You "optimize" away the access_ok / get_kernel_nofaul_allowed checks
here, but now use totally non-standard and possibly dangerous APIs.
On Thu, Apr 01, 2021 at 08:30:55AM +0200, Christoph Hellwig wrote:
> On Wed, Mar 31, 2021 at 01:56:00PM +0200, Thomas Bogendoerfer wrote:
> > +#define __get_user_nofault(dst, src, type, err_label) \
> > +do { \
> > + int __gu_err; \
> > + \
> > + __get_user_common(*((type *)(dst)), sizeof(type), \
> > + (__force type *)(src)); \
> > + if (unlikely(__gu_err)) \
> > + goto err_label; \
> > +} while (0)
> > +
> > +
> > +static inline int __get_addr(unsigned long *a, unsigned long *p, bool user)
> > +{
> > + if (user)
> > + __get_user_nofault(a, p, unsigned long, fault);
> > + else
> > + __get_kernel_nofault(a, p, unsigned long, fault);
> > +
> > + return 0;
> > +
> > +fault:
> > + return -EFAULT;
> > +}
>
> Why can't these use plain old get_user and get_kernel_nofault?
> You "optimize" away the access_ok / get_kernel_nofaul_allowed checks
> here, but now use totally non-standard and possibly dangerous APIs.
thanks, I was too deep into the macro wormhole... using standard API
makes this even look nicer. Posting v3 in a few minutes.
Thomas.
--
Crap can work. Given enough thrust pigs will fly, but it's not necessarily a
good idea. [ RFC1925, 2.3 ]