This patchset is aimed
* to improve UEFI compatibility of compressed kernel code for x86_64
* to setup proper memory access attributes for code and rodata sections
* to implement W^X protection policy throughout the whole execution
of compressed kernel for EFISTUB code path.
Kernel is made to be more compatible with PE image specification [3],
allowing it to be successfully loaded by stricter PE loader
implementations like the one from [2]. There is at least one
known implementation that uses that loader in production [4].
There are also ongoing efforts to upstream these changes.
Also the patchset adds EFI_MEMORY_ATTTRIBUTE_PROTOCOL, included into
EFI specification since version 2.10, as a better alternative to
using DXE services for memory protection attributes manipulation,
since it is defined by the UEFI specification itself and not UEFI PI
specification. This protocol is not widely available so the code
using DXE services is kept in place as a fallback in case specific
implementation does not support the new protocol.
One of EFI implementations that already support
EFI_MEMORY_ATTTRIBUTE_PROTOCOL is Microsoft Project Mu [5].
Kernel image generation tool (tools/build.c) is refactored as a part
of changes that makes PE image more compatible.
The patchset implements memory protection for compressed kernel
code while executing both inside EFI boot services and outside of
them. For EFISTUB code path W^X protection policy is maintained
throughout the whole execution of compressed kernel. The latter
is achieved by extracting the kernel directly from EFI environment
and jumping to it's head immediately after exiting EFI boot services.
As a side effect of this change one page table rebuild and a copy of
the kernel image is removed.
Direct extraction can be toggled using CONFIG_EFI_STUB_EXTRACT_DIRECT.
Memory protection inside EFI environment is controlled by the
CONFIG_DXE_MEM_ATTRIBUTES option, although with these patches this
option also control the use EFI_MEMORY_ATTTRIBUTE_PROTOCOL and memory
protection attributes of PE sections and not only DXE services as the
name might suggest.
Changes in v2:
* Fix spelling.
* Rebase code to current master.
* Split huge patches into smaller ones.
* Remove unneeded forward declarations.
* Make direct extraction unconditional.
* Also make it work for x86_32.
* Reduce lower limit of KASLR to 64M.
* Make callback interface more logically consistent.
* Actually declare callbacks structure before using it.
* Mention effect on x86_32 in commit message of
"x86/build: Remove RWX sections and align on 4KB".
* Clarify commit message of
"x86/boot: Increase boot page table size".
* Remove "startup32_" prefix on startup32_enable_nx_if_supported.
* Move linker generated sections outside of function scope.
* Drop some unintended changes.
* Drop generating 2 reloc entries.
(as I've misread the documentation and there's no need for this change.)
* Set has_nx from enable_nx_if_supported correctly.
* Move ELF header check to build time.
* Set WP at the same time as PG in trampoline code,
as it is more logically consistent.
* Put x86-specific EFISTUB definitions in x86-stub.h header.
* Catch presence of ELF segments violating W^X during build.
* Move PE definitions from build.c to a new header file.
* Fix generation of PE '.compat' section.
I decided to keep protection of compressed kernel blob and '.rodata'
separate from '.text' for now, since it does not really have a lot
of overhead.
Otherwise, all comments on v1 seems to be addressed. Please also apply
Peter's patch [6] on top of this series.
Patch "x86/boot: Support 4KB pages for identity mapping" needs review
from x86/mm team.
[1] https://lkml.org/lkml/2022/8/1/1314
[2] https://github.com/acidanthera/audk/tree/secure_pe
[3] https://download.microsoft.com/download/9/c/5/9c5b2167-8017-4bae-9fde-d599bac8184a/pecoff_v83.docx
[4] https://www.ispras.ru/en/technologies/asperitas/
[5] https://github.com/microsoft/mu_tiano_platforms
[6] https://lkml.org/lkml/2022/10/18/1178
Evgeniy Baskov (23):
x86/boot: Align vmlinuz sections on page size
x86/build: Remove RWX sections and align on 4KB
x86/boot: Set cr0 to known state in trampoline
x86/boot: Increase boot page table size
x86/boot: Support 4KB pages for identity mapping
x86/boot: Setup memory protection for bzImage code
x86/build: Check W^X of vmlinux during build
x86/boot: Map memory explicitly
x86/boot: Remove mapping from page fault handler
efi/libstub: Move helper function to related file
x86/boot: Make console interface more abstract
x86/boot: Make kernel_add_identity_map() a pointer
x86/boot: Split trampoline and pt init code
x86/boot: Add EFI kernel extraction interface
efi/x86: Support extracting kernel from libstub
x86/boot: Reduce lower limit of physical KASLR
x86/boot: Reduce size of the DOS stub
tools/include: Add simplified version of pe.h
x86/build: Cleanup tools/build.c
x86/build: Make generated PE more spec compliant
efi/x86: Explicitly set sections memory attributes
efi/libstub: Add memory attribute protocol definitions
efi/libstub: Use memory attribute protocol
arch/x86/boot/Makefile | 2 +-
arch/x86/boot/compressed/Makefile | 8 +-
arch/x86/boot/compressed/acpi.c | 21 +-
arch/x86/boot/compressed/efi.c | 19 +-
arch/x86/boot/compressed/head_32.S | 44 +-
arch/x86/boot/compressed/head_64.S | 76 ++-
arch/x86/boot/compressed/ident_map_64.c | 122 ++--
arch/x86/boot/compressed/kaslr.c | 8 +-
arch/x86/boot/compressed/misc.c | 279 ++++-----
arch/x86/boot/compressed/misc.h | 23 +-
arch/x86/boot/compressed/pgtable.h | 20 -
arch/x86/boot/compressed/pgtable_64.c | 75 ++-
arch/x86/boot/compressed/putstr.c | 130 ++++
arch/x86/boot/compressed/sev.c | 6 +-
arch/x86/boot/compressed/vmlinux.lds.S | 6 +
arch/x86/boot/header.S | 110 +---
arch/x86/boot/tools/build.c | 573 +++++++++++-------
arch/x86/include/asm/boot.h | 26 +-
arch/x86/include/asm/efi.h | 7 +
arch/x86/include/asm/init.h | 1 +
arch/x86/include/asm/shared/extract.h | 27 +
arch/x86/include/asm/shared/pgtable.h | 29 +
arch/x86/kernel/vmlinux.lds.S | 15 +-
arch/x86/mm/ident_map.c | 185 +++++-
drivers/firmware/efi/Kconfig | 2 +
drivers/firmware/efi/libstub/Makefile | 2 +-
drivers/firmware/efi/libstub/efistub.h | 26 +
drivers/firmware/efi/libstub/mem.c | 190 ++++++
.../firmware/efi/libstub/x86-extract-direct.c | 204 +++++++
drivers/firmware/efi/libstub/x86-stub.c | 231 ++-----
drivers/firmware/efi/libstub/x86-stub.h | 11 +
include/linux/efi.h | 1 +
tools/include/linux/pe.h | 150 +++++
33 files changed, 1848 insertions(+), 781 deletions(-)
delete mode 100644 arch/x86/boot/compressed/pgtable.h
create mode 100644 arch/x86/boot/compressed/putstr.c
create mode 100644 arch/x86/include/asm/shared/extract.h
create mode 100644 arch/x86/include/asm/shared/pgtable.h
create mode 100644 drivers/firmware/efi/libstub/x86-extract-direct.c
create mode 100644 drivers/firmware/efi/libstub/x86-stub.h
create mode 100644 tools/include/linux/pe.h
--
2.37.4
Implicit mappings hide possible memory errors, e.g. allocations for
ACPI tables were not included in boot page table size.
Replace all implicit mappings from page fault handler with
explicit mappings.
Signed-off-by: Evgeniy Baskov <[email protected]>
---
arch/x86/boot/compressed/acpi.c | 21 ++++++++++++++++++++-
arch/x86/boot/compressed/efi.c | 19 ++++++++++++++++++-
arch/x86/boot/compressed/kaslr.c | 4 ++++
3 files changed, 42 insertions(+), 2 deletions(-)
diff --git a/arch/x86/boot/compressed/acpi.c b/arch/x86/boot/compressed/acpi.c
index 9caf89063e77..633ac56262ee 100644
--- a/arch/x86/boot/compressed/acpi.c
+++ b/arch/x86/boot/compressed/acpi.c
@@ -93,6 +93,8 @@ static u8 *scan_mem_for_rsdp(u8 *start, u32 length)
end = start + length;
+ kernel_add_identity_map((unsigned long)start, (unsigned long)end, 0);
+
/* Search from given start address for the requested length */
for (address = start; address < end; address += ACPI_RSDP_SCAN_STEP) {
/*
@@ -128,6 +130,9 @@ static acpi_physical_address bios_get_rsdp_addr(void)
unsigned long address;
u8 *rsdp;
+ kernel_add_identity_map((unsigned long)ACPI_EBDA_PTR_LOCATION,
+ (unsigned long)ACPI_EBDA_PTR_LOCATION + 2, 0);
+
/* Get the location of the Extended BIOS Data Area (EBDA) */
address = *(u16 *)ACPI_EBDA_PTR_LOCATION;
address <<= 4;
@@ -215,6 +220,9 @@ static unsigned long get_acpi_srat_table(void)
if (!rsdp)
return 0;
+ kernel_add_identity_map((unsigned long)rsdp,
+ (unsigned long)(rsdp + 1), 0);
+
/* Get ACPI root table from RSDP.*/
if (!(cmdline_find_option("acpi", arg, sizeof(arg)) == 4 &&
!strncmp(arg, "rsdt", 4)) &&
@@ -235,6 +243,9 @@ static unsigned long get_acpi_srat_table(void)
if (len < sizeof(struct acpi_table_header) + size)
return 0;
+ kernel_add_identity_map((unsigned long)header,
+ (unsigned long)header + len, 0);
+
num_entries = (len - sizeof(struct acpi_table_header)) / size;
entry = (u8 *)(root_table + sizeof(struct acpi_table_header));
@@ -247,8 +258,16 @@ static unsigned long get_acpi_srat_table(void)
if (acpi_table) {
header = (struct acpi_table_header *)acpi_table;
- if (ACPI_COMPARE_NAMESEG(header->signature, ACPI_SIG_SRAT))
+ kernel_add_identity_map(acpi_table,
+ acpi_table + sizeof(*header),
+ 0);
+
+ if (ACPI_COMPARE_NAMESEG(header->signature, ACPI_SIG_SRAT)) {
+ kernel_add_identity_map(acpi_table,
+ acpi_table + header->length,
+ 0);
return acpi_table;
+ }
}
entry += size;
}
diff --git a/arch/x86/boot/compressed/efi.c b/arch/x86/boot/compressed/efi.c
index 6edd034b0b30..ce70103fbbc0 100644
--- a/arch/x86/boot/compressed/efi.c
+++ b/arch/x86/boot/compressed/efi.c
@@ -57,10 +57,14 @@ enum efi_type efi_get_type(struct boot_params *bp)
*/
unsigned long efi_get_system_table(struct boot_params *bp)
{
- unsigned long sys_tbl_pa;
+ static unsigned long sys_tbl_pa __section(".data");
struct efi_info *ei;
+ unsigned long sys_tbl_size;
enum efi_type et;
+ if (sys_tbl_pa)
+ return sys_tbl_pa;
+
/* Get systab from boot params. */
ei = &bp->efi_info;
#ifdef CONFIG_X86_64
@@ -73,6 +77,13 @@ unsigned long efi_get_system_table(struct boot_params *bp)
return 0;
}
+ if (efi_get_type(bp) == EFI_TYPE_64)
+ sys_tbl_size = sizeof(efi_system_table_64_t);
+ else
+ sys_tbl_size = sizeof(efi_system_table_32_t);
+
+ kernel_add_identity_map(sys_tbl_pa, sys_tbl_pa + sys_tbl_size, 0);
+
return sys_tbl_pa;
}
@@ -92,6 +103,10 @@ static struct efi_setup_data *get_kexec_setup_data(struct boot_params *bp,
pa_data = bp->hdr.setup_data;
while (pa_data) {
+ unsigned long pa_data_end = pa_data + sizeof(struct setup_data)
+ + sizeof(struct efi_setup_data);
+ kernel_add_identity_map(pa_data, pa_data_end, 0);
+
data = (struct setup_data *)pa_data;
if (data->type == SETUP_EFI) {
esd = (struct efi_setup_data *)(pa_data + sizeof(struct setup_data));
@@ -160,6 +175,8 @@ int efi_get_conf_table(struct boot_params *bp, unsigned long *cfg_tbl_pa,
return -EINVAL;
}
+ kernel_add_identity_map(*cfg_tbl_pa, *cfg_tbl_pa + *cfg_tbl_len, 0);
+
return 0;
}
diff --git a/arch/x86/boot/compressed/kaslr.c b/arch/x86/boot/compressed/kaslr.c
index e476bcbd9b42..7e09d65f7b57 100644
--- a/arch/x86/boot/compressed/kaslr.c
+++ b/arch/x86/boot/compressed/kaslr.c
@@ -688,6 +688,8 @@ process_efi_entries(unsigned long minimum, unsigned long image_size)
u32 nr_desc;
int i;
+ kernel_add_identity_map((unsigned long)e, (unsigned long)(e + 1), 0);
+
signature = (char *)&e->efi_loader_signature;
if (strncmp(signature, EFI32_LOADER_SIGNATURE, 4) &&
strncmp(signature, EFI64_LOADER_SIGNATURE, 4))
@@ -704,6 +706,8 @@ process_efi_entries(unsigned long minimum, unsigned long image_size)
pmap = (e->efi_memmap | ((__u64)e->efi_memmap_hi << 32));
#endif
+ kernel_add_identity_map(pmap, pmap + e->efi_memmap_size, 0);
+
nr_desc = e->efi_memmap_size / e->efi_memdesc_size;
for (i = 0; i < nr_desc; i++) {
md = efi_early_memdesc_ptr(pmap, e->efi_memdesc_size, i);
--
2.37.4
Check if there are simultaneously writable and executable
program segments in vmlinux ELF image and fail build if there are any.
This would prevent accidental introduction of RWX segments.
Signed-off-by: Evgeniy Baskov <[email protected]>
---
arch/x86/boot/compressed/Makefile | 6 ++++++
1 file changed, 6 insertions(+)
diff --git a/arch/x86/boot/compressed/Makefile b/arch/x86/boot/compressed/Makefile
index 3a261abb6d15..64de6c2b1740 100644
--- a/arch/x86/boot/compressed/Makefile
+++ b/arch/x86/boot/compressed/Makefile
@@ -112,11 +112,17 @@ vmlinux-objs-$(CONFIG_EFI_MIXED) += $(obj)/efi_thunk_$(BITS).o
vmlinux-objs-$(CONFIG_EFI) += $(obj)/efi.o
efi-obj-$(CONFIG_EFI_STUB) = $(objtree)/drivers/firmware/efi/libstub/lib.a
+quiet_cmd_wx_check = WXCHK $<
+cmd_wx_check = if $(OBJDUMP) -p $< | grep "flags .wx" > /dev/null; \
+ then (echo >&2 "$<: Simultaneously writable and executable sections are prohibited"; \
+ /bin/false); fi
+
$(obj)/vmlinux: $(vmlinux-objs-y) $(efi-obj-y) FORCE
$(call if_changed,ld)
OBJCOPYFLAGS_vmlinux.bin := -R .comment -S
$(obj)/vmlinux.bin: vmlinux FORCE
+ $(call cmd,wx_check)
$(call if_changed,objcopy)
targets += $(patsubst $(obj)/%,%,$(vmlinux-objs-y)) vmlinux.bin.all vmlinux.relocs
--
2.37.4
Set lower limit of physical KASLR to 64M.
Previously is was set to 512M when kernel is loaded higher than that.
That prevented physical KASLR from being performed on x86_32, where
upper limit is also set to 512M. The limit is pretty arbitrary, and the
most important is to set it above the ISA hole, i.e. higher than 16M.
It was not that important before, but now kernel is not getting
relocated to the lower address when booting via EFI, exposing the
KASLR failures.
Signed-off-by: Evgeniy Baskov <[email protected]>
---
arch/x86/boot/compressed/kaslr.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/arch/x86/boot/compressed/kaslr.c b/arch/x86/boot/compressed/kaslr.c
index 7e09d65f7b57..672550686f62 100644
--- a/arch/x86/boot/compressed/kaslr.c
+++ b/arch/x86/boot/compressed/kaslr.c
@@ -852,10 +852,10 @@ void choose_random_location(unsigned long input,
/*
* Low end of the randomization range should be the
- * smaller of 512M or the initial kernel image
+ * smaller of 64M or the initial kernel image
* location:
*/
- min_addr = min(*output, 512UL << 20);
+ min_addr = min(*output, 64UL << 20);
/* Make sure minimum is aligned. */
min_addr = ALIGN(min_addr, CONFIG_PHYSICAL_ALIGN);
--
2.37.4
Previous upper limit ignored pages implicitly mapped from #PF handler
by code accessing ACPI tables (boot/compressed/{acpi.c,efi.c}),
so theoretical upper limit is higher than it was set.
Using 4KB pages is desirable for better memory protection granularity.
Approximately twice as much memory is required for those.
Increase initial page table size to 64 4KB page tables.
Signed-off-by: Evgeniy Baskov <[email protected]>
---
arch/x86/include/asm/boot.h | 26 ++++++++++++++------------
1 file changed, 14 insertions(+), 12 deletions(-)
diff --git a/arch/x86/include/asm/boot.h b/arch/x86/include/asm/boot.h
index 9191280d9ea3..024d972c248e 100644
--- a/arch/x86/include/asm/boot.h
+++ b/arch/x86/include/asm/boot.h
@@ -41,22 +41,24 @@
# define BOOT_STACK_SIZE 0x4000
# define BOOT_INIT_PGT_SIZE (6*4096)
-# ifdef CONFIG_RANDOMIZE_BASE
/*
* Assuming all cross the 512GB boundary:
* 1 page for level4
- * (2+2)*4 pages for kernel, param, cmd_line, and randomized kernel
- * 2 pages for first 2M (video RAM: CONFIG_X86_VERBOSE_BOOTUP).
- * Total is 19 pages.
+ * (3+3)*2 pages for param and cmd_line
+ * (2+2+S)*2 pages for kernel and randomized kernel, where S is total number
+ * of sections of kernel. Explanation: 2+2 are upper level page tables.
+ * We can have only S unaligned parts of section: 1 at the end of the kernel
+ * and (S-1) at the section borders. The start address of the kernel is
+ * aligned, so an extra page table. There are at most S=6 sections in
+ * vmlinux ELF image.
+ * 3 pages for first 2M (video RAM: CONFIG_X86_VERBOSE_BOOTUP).
+ * Total is 36 pages.
+ *
+ * Some pages are also required for UEFI memory map and
+ * ACPI table mappings, so we need to add extra space.
+ * FIXME: Figure out exact amount of pages.
*/
-# ifdef CONFIG_X86_VERBOSE_BOOTUP
-# define BOOT_PGT_SIZE (19*4096)
-# else /* !CONFIG_X86_VERBOSE_BOOTUP */
-# define BOOT_PGT_SIZE (17*4096)
-# endif
-# else /* !CONFIG_RANDOMIZE_BASE */
-# define BOOT_PGT_SIZE BOOT_INIT_PGT_SIZE
-# endif
+# define BOOT_PGT_SIZE (64*4096)
#else /* !CONFIG_X86_64 */
# define BOOT_STACK_SIZE 0x1000
--
2.37.4
This is required to fit more sections in PE section tables,
since its size is restricted by zero page located at specific offset
after the PE header.
Signed-off-by: Evgeniy Baskov <[email protected]>
---
arch/x86/boot/header.S | 14 ++++++--------
1 file changed, 6 insertions(+), 8 deletions(-)
diff --git a/arch/x86/boot/header.S b/arch/x86/boot/header.S
index f912d7770130..e4de831b2f64 100644
--- a/arch/x86/boot/header.S
+++ b/arch/x86/boot/header.S
@@ -59,17 +59,16 @@ start2:
cld
movw $bugger_off_msg, %si
+ movw $bugger_off_msg_size, %cx
msg_loop:
lodsb
- andb %al, %al
- jz bs_die
movb $0xe, %ah
movw $7, %bx
int $0x10
- jmp msg_loop
+ decw %cx
+ jnz msg_loop
-bs_die:
# Allow the user to press a key, then reboot
xorw %ax, %ax
int $0x16
@@ -89,10 +88,9 @@ bs_die:
.section ".bsdata", "a"
bugger_off_msg:
- .ascii "Use a boot loader.\r\n"
- .ascii "\n"
- .ascii "Remove disk and press any key to reboot...\r\n"
- .byte 0
+ .ascii "Use a boot loader. "
+ .ascii "Press a key to reboot"
+ .set bugger_off_msg_size, . - bugger_off_msg
#ifdef CONFIG_EFI_STUB
pe_header:
--
2.37.4
Avoid creating sections simultaneously writable and readable
to prepare for W^X implementation. Align sections on page size (4KB) to
allow protecting them in the page tables.
Split init code form ".init" segment into separate R_X ".inittext"
segment and make ".init" segment non-executable.
Also add these segments to x86_32 architecture for consistency.
Currently paging is disabled in x86_32 in compressed kernel, so
protection is not applied anyways, but .init code was incorrectly
placed in non-executable ".data" segment. This should not change
anything meaningful in memory layout now, but might be required in case
memory protection will also be implemented in compressed kernel for
x86_32.
Signed-off-by: Evgeniy Baskov <[email protected]>
---
arch/x86/kernel/vmlinux.lds.S | 15 ++++++++-------
1 file changed, 8 insertions(+), 7 deletions(-)
diff --git a/arch/x86/kernel/vmlinux.lds.S b/arch/x86/kernel/vmlinux.lds.S
index 15f29053cec4..6587e0201b50 100644
--- a/arch/x86/kernel/vmlinux.lds.S
+++ b/arch/x86/kernel/vmlinux.lds.S
@@ -102,12 +102,11 @@ jiffies = jiffies_64;
PHDRS {
text PT_LOAD FLAGS(5); /* R_E */
data PT_LOAD FLAGS(6); /* RW_ */
-#ifdef CONFIG_X86_64
-#ifdef CONFIG_SMP
+#if defined(CONFIG_X86_64) && defined(CONFIG_SMP)
percpu PT_LOAD FLAGS(6); /* RW_ */
#endif
- init PT_LOAD FLAGS(7); /* RWE */
-#endif
+ inittext PT_LOAD FLAGS(5); /* R_E */
+ init PT_LOAD FLAGS(6); /* RW_ */
note PT_NOTE FLAGS(0); /* ___ */
}
@@ -226,9 +225,10 @@ SECTIONS
#endif
INIT_TEXT_SECTION(PAGE_SIZE)
-#ifdef CONFIG_X86_64
- :init
-#endif
+ :inittext
+
+ . = ALIGN(PAGE_SIZE);
+
/*
* Section for code used exclusively before alternatives are run. All
@@ -240,6 +240,7 @@ SECTIONS
.altinstr_aux : AT(ADDR(.altinstr_aux) - LOAD_OFFSET) {
*(.altinstr_aux)
}
+ :init
INIT_DATA_SECTION(16)
--
2.37.4
This is needed to remove magic numbers from x86 bzImage building tool
(arch/x86/boot/tools/build.c).
Signed-off-by: Evgeniy Baskov <[email protected]>
---
tools/include/linux/pe.h | 150 +++++++++++++++++++++++++++++++++++++++
1 file changed, 150 insertions(+)
create mode 100644 tools/include/linux/pe.h
diff --git a/tools/include/linux/pe.h b/tools/include/linux/pe.h
new file mode 100644
index 000000000000..41c09ec371d8
--- /dev/null
+++ b/tools/include/linux/pe.h
@@ -0,0 +1,150 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * Simplified version of include/linux/pe.h:
+ * Copyright 2011 Red Hat, Inc. All rights reserved.
+ * Author(s): Peter Jones <[email protected]>
+ */
+#ifndef __LINUX_PE_H
+#define __LINUX_PE_H
+
+#include <linux/types.h>
+
+#define IMAGE_FILE_MACHINE_I386 0x014c
+
+#define IMAGE_SCN_CNT_CODE 0x00000020 /* .text */
+#define IMAGE_SCN_CNT_INITIALIZED_DATA 0x00000040 /* .data */
+#define IMAGE_SCN_ALIGN_4096BYTES 0x00d00000
+#define IMAGE_SCN_MEM_DISCARDABLE 0x02000000 /* scn can be discarded */
+#define IMAGE_SCN_MEM_EXECUTE 0x20000000 /* can be executed as code */
+#define IMAGE_SCN_MEM_READ 0x40000000 /* readable */
+#define IMAGE_SCN_MEM_WRITE 0x80000000 /* writeable */
+
+#define MZ_HEADER_PEADDR_OFFSET 0x3c
+
+struct pe_hdr {
+ uint32_t magic; /* PE magic */
+ uint16_t machine; /* machine type */
+ uint16_t sections; /* number of sections */
+ uint32_t timestamp; /* time_t */
+ uint32_t symbol_table; /* symbol table offset */
+ uint32_t symbols; /* number of symbols */
+ uint16_t opt_hdr_size; /* size of optional header */
+ uint16_t flags; /* flags */
+};
+
+/* the fact that pe32 isn't padded where pe32+ is 64-bit means union won't
+ * work right. vomit. */
+struct pe32_opt_hdr {
+ /* "standard" header */
+ uint16_t magic; /* file type */
+ uint8_t ld_major; /* linker major version */
+ uint8_t ld_minor; /* linker minor version */
+ uint32_t text_size; /* size of text section(s) */
+ uint32_t data_size; /* size of data section(s) */
+ uint32_t bss_size; /* size of bss section(s) */
+ uint32_t entry_point; /* file offset of entry point */
+ uint32_t code_base; /* relative code addr in ram */
+ uint32_t data_base; /* relative data addr in ram */
+ /* "windows" header */
+ uint32_t image_base; /* preferred load address */
+ uint32_t section_align; /* alignment in bytes */
+ uint32_t file_align; /* file alignment in bytes */
+ uint16_t os_major; /* major OS version */
+ uint16_t os_minor; /* minor OS version */
+ uint16_t image_major; /* major image version */
+ uint16_t image_minor; /* minor image version */
+ uint16_t subsys_major; /* major subsystem version */
+ uint16_t subsys_minor; /* minor subsystem version */
+ uint32_t win32_version; /* reserved, must be 0 */
+ uint32_t image_size; /* image size */
+ uint32_t header_size; /* header size rounded up to
+ file_align */
+ uint32_t csum; /* checksum */
+ uint16_t subsys; /* subsystem */
+ uint16_t dll_flags; /* more flags! */
+ uint32_t stack_size_req;/* amt of stack requested */
+ uint32_t stack_size; /* amt of stack required */
+ uint32_t heap_size_req; /* amt of heap requested */
+ uint32_t heap_size; /* amt of heap required */
+ uint32_t loader_flags; /* reserved, must be 0 */
+ uint32_t data_dirs; /* number of data dir entries */
+};
+
+struct pe32plus_opt_hdr {
+ uint16_t magic; /* file type */
+ uint8_t ld_major; /* linker major version */
+ uint8_t ld_minor; /* linker minor version */
+ uint32_t text_size; /* size of text section(s) */
+ uint32_t data_size; /* size of data section(s) */
+ uint32_t bss_size; /* size of bss section(s) */
+ uint32_t entry_point; /* file offset of entry point */
+ uint32_t code_base; /* relative code addr in ram */
+ /* "windows" header */
+ uint64_t image_base; /* preferred load address */
+ uint32_t section_align; /* alignment in bytes */
+ uint32_t file_align; /* file alignment in bytes */
+ uint16_t os_major; /* major OS version */
+ uint16_t os_minor; /* minor OS version */
+ uint16_t image_major; /* major image version */
+ uint16_t image_minor; /* minor image version */
+ uint16_t subsys_major; /* major subsystem version */
+ uint16_t subsys_minor; /* minor subsystem version */
+ uint32_t win32_version; /* reserved, must be 0 */
+ uint32_t image_size; /* image size */
+ uint32_t header_size; /* header size rounded up to
+ file_align */
+ uint32_t csum; /* checksum */
+ uint16_t subsys; /* subsystem */
+ uint16_t dll_flags; /* more flags! */
+ uint64_t stack_size_req;/* amt of stack requested */
+ uint64_t stack_size; /* amt of stack required */
+ uint64_t heap_size_req; /* amt of heap requested */
+ uint64_t heap_size; /* amt of heap required */
+ uint32_t loader_flags; /* reserved, must be 0 */
+ uint32_t data_dirs; /* number of data dir entries */
+};
+
+struct data_dirent {
+ uint32_t virtual_address; /* relative to load address */
+ uint32_t size;
+};
+
+struct data_directory {
+ struct data_dirent exports; /* .edata */
+ struct data_dirent imports; /* .idata */
+ struct data_dirent resources; /* .rsrc */
+ struct data_dirent exceptions; /* .pdata */
+ struct data_dirent certs; /* certs */
+ struct data_dirent base_relocations; /* .reloc */
+ struct data_dirent debug; /* .debug */
+ struct data_dirent arch; /* reservered */
+ struct data_dirent global_ptr; /* global pointer reg. Size=0 */
+ struct data_dirent tls; /* .tls */
+ struct data_dirent load_config; /* load configuration structure */
+ struct data_dirent bound_imports; /* no idea */
+ struct data_dirent import_addrs; /* import address table */
+ struct data_dirent delay_imports; /* delay-load import table */
+ struct data_dirent clr_runtime_hdr; /* .cor (object only) */
+ struct data_dirent reserved;
+};
+
+struct section_header {
+ char name[8]; /* name or "/12\0" string tbl offset */
+ uint32_t virtual_size; /* size of loaded section in ram */
+ uint32_t virtual_address; /* relative virtual address */
+ uint32_t raw_data_size; /* size of the section */
+ uint32_t data_addr; /* file pointer to first page of sec */
+ uint32_t relocs; /* file pointer to relocation entries */
+ uint32_t line_numbers; /* line numbers! */
+ uint16_t num_relocs; /* number of relocations */
+ uint16_t num_lin_numbers; /* srsly. */
+ uint32_t flags;
+};
+
+struct coff_reloc {
+ uint32_t virtual_address;
+ uint32_t symbol_table_index;
+ uint16_t data;
+};
+
+#endif /* __LINUX_PE_H */
--
2.37.4
Use previously added code to use 4KB pages for mapping. Map compressed
and uncompressed kernel with appropriate memory protection attributes.
For compressed kernel set them up manually. For uncompressed kernel
used flags specified in ELF header.
Signed-off-by: Evgeniy Baskov <[email protected]>
delete mode 100644 arch/x86/boot/compressed/pgtable.h
create mode 100644 arch/x86/include/asm/shared/pgtable.h
---
arch/x86/boot/compressed/head_64.S | 24 +++++-
arch/x86/boot/compressed/ident_map_64.c | 97 ++++++++++++++++---------
arch/x86/boot/compressed/misc.c | 63 ++++++++++++++--
arch/x86/boot/compressed/misc.h | 22 +++++-
arch/x86/boot/compressed/pgtable.h | 20 -----
arch/x86/boot/compressed/pgtable_64.c | 2 +-
arch/x86/boot/compressed/sev.c | 6 +-
arch/x86/include/asm/shared/pgtable.h | 29 ++++++++
8 files changed, 197 insertions(+), 66 deletions(-)
delete mode 100644 arch/x86/boot/compressed/pgtable.h
create mode 100644 arch/x86/include/asm/shared/pgtable.h
diff --git a/arch/x86/boot/compressed/head_64.S b/arch/x86/boot/compressed/head_64.S
index 2a4372b84fc8..73a2ac2b063d 100644
--- a/arch/x86/boot/compressed/head_64.S
+++ b/arch/x86/boot/compressed/head_64.S
@@ -29,13 +29,14 @@
#include <linux/linkage.h>
#include <asm/segment.h>
#include <asm/boot.h>
+#include <asm/cpufeatures.h>
#include <asm/msr.h>
#include <asm/processor-flags.h>
#include <asm/asm-offsets.h>
#include <asm/bootparam.h>
#include <asm/desc_defs.h>
#include <asm/trapnr.h>
-#include "pgtable.h"
+#include <asm/shared/pgtable.h>
/*
* Locally defined symbols should be marked hidden:
@@ -578,6 +579,7 @@ SYM_FUNC_START_LOCAL_NOALIGN(.Lrelocated)
pushq %rsi
call load_stage2_idt
+ call enable_nx_if_supported
/* Pass boot_params to initialize_identity_maps() */
movq (%rsp), %rdi
call initialize_identity_maps
@@ -602,6 +604,26 @@ SYM_FUNC_START_LOCAL_NOALIGN(.Lrelocated)
jmp *%rax
SYM_FUNC_END(.Lrelocated)
+SYM_FUNC_START_LOCAL_NOALIGN(enable_nx_if_supported)
+ pushq %rbx
+
+ mov $0x80000001, %eax
+ cpuid
+ btl $(X86_FEATURE_NX & 31), %edx
+ jnc .Lnonx
+
+ movl $MSR_EFER, %ecx
+ rdmsr
+ btsl $_EFER_NX, %eax
+ wrmsr
+
+ movb $1, has_nx(%rip)
+
+.Lnonx:
+ popq %rbx
+ RET
+SYM_FUNC_END(enable_nx_if_supported)
+
.code32
/*
* This is the 32-bit trampoline that will be copied over to low memory.
diff --git a/arch/x86/boot/compressed/ident_map_64.c b/arch/x86/boot/compressed/ident_map_64.c
index d4a314cc50d6..fec795a4ce23 100644
--- a/arch/x86/boot/compressed/ident_map_64.c
+++ b/arch/x86/boot/compressed/ident_map_64.c
@@ -28,6 +28,7 @@
#include <asm/trap_pf.h>
#include <asm/trapnr.h>
#include <asm/init.h>
+#include <asm/shared/pgtable.h>
/* Use the static base for this part of the boot process */
#undef __PAGE_OFFSET
#define __PAGE_OFFSET __PAGE_OFFSET_BASE
@@ -86,24 +87,52 @@ phys_addr_t physical_mask = (1ULL << __PHYSICAL_MASK_SHIFT) - 1;
* Due to relocation, pointers must be assigned at run time not build time.
*/
static struct x86_mapping_info mapping_info;
+bool has_nx; /* set in head_64.S */
/*
* Adds the specified range to the identity mappings.
*/
-void kernel_add_identity_map(unsigned long start, unsigned long end)
+unsigned long kernel_add_identity_map(unsigned long start,
+ unsigned long end,
+ unsigned int flags)
{
int ret;
/* Align boundary to 2M. */
- start = round_down(start, PMD_SIZE);
- end = round_up(end, PMD_SIZE);
+ start = round_down(start, PAGE_SIZE);
+ end = round_up(end, PAGE_SIZE);
if (start >= end)
- return;
+ return start;
+
+ /*
+ * Warn if W^X is violated.
+ * Only do that if CONFIG_RANDOMIZE_BASE is set, since otherwise we need
+ * to create RWX region in case of overlapping memory regions for
+ * compressed and uncompressed kernel.
+ */
+
+ if (IS_ENABLED(CONFIG_RANDOMIZE_BASE) &&
+ (flags & (MAP_EXEC | MAP_WRITE)) == (MAP_EXEC | MAP_WRITE))
+ warn("W^X violation\n");
+
+ bool nx = !(flags & MAP_EXEC) && has_nx;
+ bool ro = !(flags & MAP_WRITE);
+
+ mapping_info.page_flag = sme_me_mask | (nx ?
+ (ro ? __PAGE_KERNEL_RO : __PAGE_KERNEL) :
+ (ro ? __PAGE_KERNEL_ROX : __PAGE_KERNEL_EXEC));
/* Build the mapping. */
- ret = kernel_ident_mapping_init(&mapping_info, (pgd_t *)top_level_pgt, start, end);
+ ret = kernel_ident_mapping_init(&mapping_info,
+ (pgd_t *)top_level_pgt,
+ start, end);
if (ret)
error("Error: kernel_ident_mapping_init() failed\n");
+
+ if (!(flags & MAP_NOFLUSH))
+ write_cr3(top_level_pgt);
+
+ return start;
}
/* Locates and clears a region for a new top level page table. */
@@ -112,14 +141,17 @@ void initialize_identity_maps(void *rmode)
unsigned long cmdline;
struct setup_data *sd;
+ boot_params = rmode;
+
/* Exclude the encryption mask from __PHYSICAL_MASK */
physical_mask &= ~sme_me_mask;
/* Init mapping_info with run-time function/buffer pointers. */
mapping_info.alloc_pgt_page = alloc_pgt_page;
mapping_info.context = &pgt_data;
- mapping_info.page_flag = __PAGE_KERNEL_LARGE_EXEC | sme_me_mask;
+ mapping_info.page_flag = __PAGE_KERNEL_EXEC | sme_me_mask;
mapping_info.kernpg_flag = _KERNPG_TABLE;
+ mapping_info.allow_4kpages = 1;
/*
* It should be impossible for this not to already be true,
@@ -154,15 +186,29 @@ void initialize_identity_maps(void *rmode)
/*
* New page-table is set up - map the kernel image, boot_params and the
* command line. The uncompressed kernel requires boot_params and the
- * command line to be mapped in the identity mapping. Map them
- * explicitly here in case the compressed kernel does not touch them,
- * or does not touch all the pages covering them.
+ * command line to be mapped in the identity mapping.
+ * Every other accessed memory region is mapped later, if required.
*/
- kernel_add_identity_map((unsigned long)_head, (unsigned long)_end);
- boot_params = rmode;
- kernel_add_identity_map((unsigned long)boot_params, (unsigned long)(boot_params + 1));
+ kernel_add_identity_map((unsigned long)_head,
+ (unsigned long)_ehead, MAP_EXEC | MAP_NOFLUSH);
+
+ kernel_add_identity_map((unsigned long)_compressed,
+ (unsigned long)_ecompressed, MAP_WRITE | MAP_NOFLUSH);
+
+ kernel_add_identity_map((unsigned long)_text,
+ (unsigned long)_etext, MAP_EXEC | MAP_NOFLUSH);
+
+ kernel_add_identity_map((unsigned long)_rodata,
+ (unsigned long)_erodata, MAP_NOFLUSH);
+
+ kernel_add_identity_map((unsigned long)_data,
+ (unsigned long)_end, MAP_WRITE | MAP_NOFLUSH);
+
+ kernel_add_identity_map((unsigned long)boot_params,
+ (unsigned long)(boot_params + 1), MAP_WRITE | MAP_NOFLUSH);
+
cmdline = get_cmd_line_ptr();
- kernel_add_identity_map(cmdline, cmdline + COMMAND_LINE_SIZE);
+ kernel_add_identity_map(cmdline, cmdline + COMMAND_LINE_SIZE, MAP_NOFLUSH);
/*
* Also map the setup_data entries passed via boot_params in case they
@@ -172,7 +218,7 @@ void initialize_identity_maps(void *rmode)
while (sd) {
unsigned long sd_addr = (unsigned long)sd;
- kernel_add_identity_map(sd_addr, sd_addr + sizeof(*sd) + sd->len);
+ kernel_add_identity_map(sd_addr, sd_addr + sizeof(*sd) + sd->len, MAP_NOFLUSH);
sd = (struct setup_data *)sd->next;
}
@@ -185,26 +231,11 @@ void initialize_identity_maps(void *rmode)
static pte_t *split_large_pmd(struct x86_mapping_info *info,
pmd_t *pmdp, unsigned long __address)
{
- unsigned long page_flags;
- unsigned long address;
- pte_t *pte;
- pmd_t pmd;
- int i;
-
- pte = (pte_t *)info->alloc_pgt_page(info->context);
+ unsigned long address = __address & PMD_MASK;
+ pte_t *pte = ident_split_large_pmd(info, pmdp, address);
if (!pte)
return NULL;
- address = __address & PMD_MASK;
- /* No large page - clear PSE flag */
- page_flags = info->page_flag & ~_PAGE_PSE;
-
- /* Populate the PTEs */
- for (i = 0; i < PTRS_PER_PMD; i++) {
- set_pte(&pte[i], __pte(address | page_flags));
- address += PAGE_SIZE;
- }
-
/*
* Ideally we need to clear the large PMD first and do a TLB
* flush before we write the new PMD. But the 2M range of the
@@ -214,7 +245,7 @@ static pte_t *split_large_pmd(struct x86_mapping_info *info,
* also the only user of the page-table, so there is no chance
* of a TLB multihit.
*/
- pmd = __pmd((unsigned long)pte | info->kernpg_flag);
+ pmd_t pmd = __pmd((unsigned long)pte | info->kernpg_flag);
set_pmd(pmdp, pmd);
/* Flush TLB to establish the new PMD */
write_cr3(top_level_pgt);
@@ -377,5 +408,5 @@ void do_boot_page_fault(struct pt_regs *regs, unsigned long error_code)
* Error code is sane - now identity map the 2M region around
* the faulting address.
*/
- kernel_add_identity_map(address, end);
+ kernel_add_identity_map(address, end, MAP_WRITE);
}
diff --git a/arch/x86/boot/compressed/misc.c b/arch/x86/boot/compressed/misc.c
index cf690d8712f4..0c7ec290044d 100644
--- a/arch/x86/boot/compressed/misc.c
+++ b/arch/x86/boot/compressed/misc.c
@@ -14,10 +14,10 @@
#include "misc.h"
#include "error.h"
-#include "pgtable.h"
#include "../string.h"
#include "../voffset.h"
#include <asm/bootparam_utils.h>
+#include <asm/shared/pgtable.h>
/*
* WARNING!!
@@ -277,7 +277,8 @@ static inline void handle_relocations(void *output, unsigned long output_len,
{ }
#endif
-static void parse_elf(void *output)
+static void parse_elf(void *output, unsigned long output_len,
+ unsigned long virt_addr)
{
#ifdef CONFIG_X86_64
Elf64_Ehdr ehdr;
@@ -287,6 +288,7 @@ static void parse_elf(void *output)
Elf32_Phdr *phdrs, *phdr;
#endif
void *dest;
+ unsigned long addr;
int i;
memcpy(&ehdr, output, sizeof(ehdr));
@@ -323,10 +325,49 @@ static void parse_elf(void *output)
#endif
memmove(dest, output + phdr->p_offset, phdr->p_filesz);
break;
- default: /* Ignore other PT_* */ break;
+ default:
+ /* Ignore other PT_* */
+ break;
+ }
+ }
+
+ handle_relocations(output, output_len, virt_addr);
+
+ if (!IS_ENABLED(CONFIG_RANDOMIZE_BASE))
+ goto skip_protect;
+
+ for (i = 0; i < ehdr.e_phnum; i++) {
+ phdr = &phdrs[i];
+
+ switch (phdr->p_type) {
+ case PT_LOAD:
+#ifdef CONFIG_RELOCATABLE
+ addr = (unsigned long)output;
+ addr += (phdr->p_paddr - LOAD_PHYSICAL_ADDR);
+#else
+ addr = phdr->p_paddr;
+#endif
+ /*
+ * Simultaneously readable and writable segments are
+ * violating W^X, and should not be present in vmlinux image.
+ * The absence of such segments is checked during build.
+ */
+
+ unsigned int flags = MAP_PROTECT;
+ if (phdr->p_flags & PF_X)
+ flags |= MAP_EXEC;
+ if (phdr->p_flags & PF_W)
+ flags |= MAP_WRITE;
+
+ kernel_add_identity_map(addr, addr + phdr->p_memsz, flags);
+ break;
+ default:
+ /* Ignore other PT_* */
+ break;
}
}
+skip_protect:
free(phdrs);
}
@@ -434,6 +475,19 @@ asmlinkage __visible void *extract_kernel(void *rmode, memptr heap,
needed_size,
&virt_addr);
+ unsigned long phys_addr = (unsigned long)output;
+
+ /*
+ * If KASLR is disabled input and output regions may overlap.
+ * In this case we need to map region excutable as well.
+ */
+ unsigned long map_flags = MAP_ALLOC | MAP_WRITE |
+ (IS_ENABLED(CONFIG_RANDOMIZE_BASE) ? 0 : MAP_EXEC);
+ phys_addr = kernel_add_identity_map(phys_addr,
+ phys_addr + needed_size,
+ map_flags);
+ output = (unsigned char *)phys_addr;
+
/* Validate memory location choices. */
if ((unsigned long)output & (MIN_KERNEL_ALIGN - 1))
error("Destination physical address inappropriately aligned");
@@ -456,8 +510,7 @@ asmlinkage __visible void *extract_kernel(void *rmode, memptr heap,
debug_putstr("\nDecompressing Linux... ");
__decompress(input_data, input_len, NULL, NULL, output, output_len,
NULL, error);
- parse_elf(output);
- handle_relocations(output, output_len, virt_addr);
+ parse_elf(output, output_len, virt_addr);
debug_putstr("done.\nBooting the kernel.\n");
/* Disable exception handling before booting the kernel */
diff --git a/arch/x86/boot/compressed/misc.h b/arch/x86/boot/compressed/misc.h
index 62208ec04ca4..033db9b536e6 100644
--- a/arch/x86/boot/compressed/misc.h
+++ b/arch/x86/boot/compressed/misc.h
@@ -44,8 +44,12 @@
#define memptr unsigned
#endif
-/* boot/compressed/vmlinux start and end markers */
-extern char _head[], _end[];
+/* Compressed kernel section start/end markers. */
+extern char _head[], _ehead[];
+extern char _compressed[], _ecompressed[];
+extern char _text[], _etext[];
+extern char _rodata[], _erodata[];
+extern char _data[], _end[];
/* misc.c */
extern memptr free_mem_ptr;
@@ -171,8 +175,18 @@ static inline int count_immovable_mem_regions(void) { return 0; }
#ifdef CONFIG_X86_5LEVEL
extern unsigned int __pgtable_l5_enabled, pgdir_shift, ptrs_per_p4d;
#endif
-extern void kernel_add_identity_map(unsigned long start, unsigned long end);
-
+#ifdef CONFIG_X86_64
+extern unsigned long kernel_add_identity_map(unsigned long start,
+ unsigned long end,
+ unsigned int flags);
+#else
+static inline unsigned long kernel_add_identity_map(unsigned long start,
+ unsigned long end,
+ unsigned int flags)
+{
+ return start;
+}
+#endif
/* Used by PAGE_KERN* macros: */
extern pteval_t __default_kernel_pte_mask;
diff --git a/arch/x86/boot/compressed/pgtable.h b/arch/x86/boot/compressed/pgtable.h
deleted file mode 100644
index cc9b2529a086..000000000000
--- a/arch/x86/boot/compressed/pgtable.h
+++ /dev/null
@@ -1,20 +0,0 @@
-#ifndef BOOT_COMPRESSED_PAGETABLE_H
-#define BOOT_COMPRESSED_PAGETABLE_H
-
-#define TRAMPOLINE_32BIT_SIZE (2 * PAGE_SIZE)
-
-#define TRAMPOLINE_32BIT_PGTABLE_OFFSET 0
-
-#define TRAMPOLINE_32BIT_CODE_OFFSET PAGE_SIZE
-#define TRAMPOLINE_32BIT_CODE_SIZE 0x80
-
-#define TRAMPOLINE_32BIT_STACK_END TRAMPOLINE_32BIT_SIZE
-
-#ifndef __ASSEMBLER__
-
-extern unsigned long *trampoline_32bit;
-
-extern void trampoline_32bit_src(void *return_ptr);
-
-#endif /* __ASSEMBLER__ */
-#endif /* BOOT_COMPRESSED_PAGETABLE_H */
diff --git a/arch/x86/boot/compressed/pgtable_64.c b/arch/x86/boot/compressed/pgtable_64.c
index 2ac12ff4111b..c7cf5a1059a8 100644
--- a/arch/x86/boot/compressed/pgtable_64.c
+++ b/arch/x86/boot/compressed/pgtable_64.c
@@ -2,7 +2,7 @@
#include "misc.h"
#include <asm/e820/types.h>
#include <asm/processor.h>
-#include "pgtable.h"
+#include <asm/shared/pgtable.h>
#include "../string.h"
#include "efi.h"
diff --git a/arch/x86/boot/compressed/sev.c b/arch/x86/boot/compressed/sev.c
index c93930d5ccbd..99f3ad0b30f3 100644
--- a/arch/x86/boot/compressed/sev.c
+++ b/arch/x86/boot/compressed/sev.c
@@ -13,6 +13,7 @@
#include "misc.h"
#include <asm/pgtable_types.h>
+#include <asm/shared/pgtable.h>
#include <asm/sev.h>
#include <asm/trapnr.h>
#include <asm/trap_pf.h>
@@ -435,10 +436,11 @@ void sev_prep_identity_maps(unsigned long top_level_pgt)
unsigned long cc_info_pa = boot_params->cc_blob_address;
struct cc_blob_sev_info *cc_info;
- kernel_add_identity_map(cc_info_pa, cc_info_pa + sizeof(*cc_info));
+ kernel_add_identity_map(cc_info_pa, cc_info_pa + sizeof(*cc_info), MAP_NOFLUSH);
cc_info = (struct cc_blob_sev_info *)cc_info_pa;
- kernel_add_identity_map(cc_info->cpuid_phys, cc_info->cpuid_phys + cc_info->cpuid_len);
+ kernel_add_identity_map(cc_info->cpuid_phys,
+ cc_info->cpuid_phys + cc_info->cpuid_len, MAP_NOFLUSH);
}
sev_verify_cbit(top_level_pgt);
diff --git a/arch/x86/include/asm/shared/pgtable.h b/arch/x86/include/asm/shared/pgtable.h
new file mode 100644
index 000000000000..6527dadf39d6
--- /dev/null
+++ b/arch/x86/include/asm/shared/pgtable.h
@@ -0,0 +1,29 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef ASM_SHARED_PAGETABLE_H
+#define ASM_SHARED_PAGETABLE_H
+
+#define MAP_WRITE 0x02 /* Writable memory */
+#define MAP_EXEC 0x04 /* Executable memory */
+#define MAP_ALLOC 0x10 /* Range needs to be allocated */
+#define MAP_PROTECT 0x20 /* Set exact memory attributes for memory range */
+#define MAP_NOFLUSH 0x40 /* Avoid flushing TLB */
+
+#define TRAMPOLINE_32BIT_SIZE (3 * PAGE_SIZE)
+
+#define TRAMPOLINE_32BIT_PLACEMENT_MAX (0xA0000)
+
+#define TRAMPOLINE_32BIT_PGTABLE_OFFSET 0
+
+#define TRAMPOLINE_32BIT_CODE_OFFSET PAGE_SIZE
+#define TRAMPOLINE_32BIT_CODE_SIZE 0x80
+
+#define TRAMPOLINE_32BIT_STACK_END TRAMPOLINE_32BIT_SIZE
+
+#ifndef __ASSEMBLER__
+
+extern unsigned long *trampoline_32bit;
+
+extern void trampoline_32bit_src(void *return_ptr);
+
+#endif /* __ASSEMBLER__ */
+#endif /* ASM_SHARED_PAGETABLE_H */
--
2.37.4
To enable extraction of kernel image from EFI stub code directly
extraction code needs to have separate interface that avoid part
of low level initialization logic, i.e. serial port setup.
Add kernel extraction function callable from libstub as a part
of preparation for extracting the kernel directly from EFI environment.
Signed-off-by: Evgeniy Baskov <[email protected]>
---
arch/x86/boot/compressed/head_32.S | 3 +-
arch/x86/boot/compressed/head_64.S | 2 +-
arch/x86/boot/compressed/misc.c | 101 +++++++++++++++++---------
arch/x86/boot/compressed/misc.h | 1 +
arch/x86/include/asm/shared/extract.h | 27 +++++++
5 files changed, 98 insertions(+), 36 deletions(-)
create mode 100644 arch/x86/include/asm/shared/extract.h
diff --git a/arch/x86/boot/compressed/head_32.S b/arch/x86/boot/compressed/head_32.S
index 3b354eb9516d..b46a1c4109cf 100644
--- a/arch/x86/boot/compressed/head_32.S
+++ b/arch/x86/boot/compressed/head_32.S
@@ -217,8 +217,7 @@ SYM_DATA(image_offset, .long 0)
*/
.bss
.balign 4
-boot_heap:
- .fill BOOT_HEAP_SIZE, 1, 0
+SYM_DATA(boot_heap, .fill BOOT_HEAP_SIZE, 1, 0)
boot_stack:
.fill BOOT_STACK_SIZE, 1, 0
boot_stack_end:
diff --git a/arch/x86/boot/compressed/head_64.S b/arch/x86/boot/compressed/head_64.S
index 73a2ac2b063d..6cfcdeb4531b 100644
--- a/arch/x86/boot/compressed/head_64.S
+++ b/arch/x86/boot/compressed/head_64.S
@@ -1006,7 +1006,7 @@ SYM_FUNC_END(startup32_check_sev_cbit)
*/
.bss
.balign 4
-SYM_DATA_LOCAL(boot_heap, .fill BOOT_HEAP_SIZE, 1, 0)
+SYM_DATA(boot_heap, .fill BOOT_HEAP_SIZE, 1, 0)
SYM_DATA_START_LOCAL(boot_stack)
.fill BOOT_STACK_SIZE, 1, 0
diff --git a/arch/x86/boot/compressed/misc.c b/arch/x86/boot/compressed/misc.c
index c9c235d65d16..59264720e87e 100644
--- a/arch/x86/boot/compressed/misc.c
+++ b/arch/x86/boot/compressed/misc.c
@@ -308,11 +308,11 @@ static inline unsigned long kernel_add_identity_map_dummy(unsigned long start,
* |-------uncompressed kernel image---------|
*
*/
-asmlinkage __visible void *extract_kernel(void *rmode, memptr heap,
- unsigned char *input_data,
- unsigned long input_len,
- unsigned char *output,
- unsigned long output_len)
+static void *do_extract_kernel(void *rmode,
+ unsigned char *input_data,
+ unsigned long input_len,
+ unsigned char *output,
+ unsigned long output_len)
{
const unsigned long kernel_total_size = VO__end - VO__text;
unsigned long virt_addr = LOAD_PHYSICAL_ADDR;
@@ -326,26 +326,6 @@ asmlinkage __visible void *extract_kernel(void *rmode, memptr heap,
sanitize_boot_params(boot_params);
- init_default_io_ops();
-
- /*
- * On 64-bit this pointer is set during page table uninitialization,
- * but on 32-bit it remains uninitialized, since paging is disabled.
- */
- if (IS_ENABLED(CONFIG_X86_32))
- kernel_add_identity_map = kernel_add_identity_map_dummy;
-
-
- /*
- * Detect TDX guest environment.
- *
- * It has to be done before console_init() in order to use
- * paravirtualized port I/O operations if needed.
- */
- early_tdx_detect();
-
- init_bare_console();
-
/*
* Save RSDP address for later use. Have this after console_init()
* so that early debugging output from the RSDP parsing code can be
@@ -353,11 +333,6 @@ asmlinkage __visible void *extract_kernel(void *rmode, memptr heap,
*/
boot_params->acpi_rsdp_addr = get_rsdp_addr();
- debug_putstr("early console in extract_kernel\n");
-
- free_mem_ptr = heap; /* Heap */
- free_mem_end_ptr = heap + BOOT_HEAP_SIZE;
-
/*
* The memory hole needed for the kernel is the larger of either
* the entire decompressed kernel plus relocation table, or the
@@ -411,12 +386,12 @@ asmlinkage __visible void *extract_kernel(void *rmode, memptr heap,
if (virt_addr & (MIN_KERNEL_ALIGN - 1))
error("Destination virtual address inappropriately aligned");
#ifdef CONFIG_X86_64
- if (heap > 0x3fffffffffffUL)
+ if (phys_addr > 0x3fffffffffffUL)
error("Destination address too large");
if (virt_addr + max(output_len, kernel_total_size) > KERNEL_IMAGE_SIZE)
error("Destination virtual address is beyond the kernel mapping area");
#else
- if (heap > ((-__PAGE_OFFSET-(128<<20)-1) & 0x7fffffff))
+ if (phys_addr > ((-__PAGE_OFFSET-(128<<20)-1) & 0x7fffffff))
error("Destination address too large");
#endif
#ifndef CONFIG_RELOCATABLE
@@ -430,12 +405,72 @@ asmlinkage __visible void *extract_kernel(void *rmode, memptr heap,
parse_elf(output, output_len, virt_addr);
debug_putstr("done.\nBooting the kernel.\n");
+ return output;
+}
+
+asmlinkage __visible void *extract_kernel(void *rmode, memptr heap,
+ unsigned char *input_data,
+ unsigned long input_len,
+ unsigned char *output,
+ unsigned long output_len)
+{
+ void *entry;
+
+ init_default_io_ops();
+
+ /*
+ * On 64-bit this pointer is set during page table uninitialization,
+ * but on 32-bit it remains uninitialized, since paging is disabled.
+ */
+ if (IS_ENABLED(CONFIG_X86_32))
+ kernel_add_identity_map = kernel_add_identity_map_dummy;
+
+ /*
+ * Detect TDX guest environment.
+ *
+ * It has to be done before console_init() in order to use
+ * paravirtualized port I/O operations if needed.
+ */
+ early_tdx_detect();
+
+ init_bare_console();
+
+ debug_putstr("early console in extract_kernel\n");
+
+ free_mem_ptr = heap; /* Heap */
+ free_mem_end_ptr = heap + BOOT_HEAP_SIZE;
+
+ entry = do_extract_kernel(rmode, input_data,
+ input_len, output, output_len);
+
/* Disable exception handling before booting the kernel */
cleanup_exception_handling();
- return output;
+ return entry;
}
+void *efi_extract_kernel(struct boot_params *rmode,
+ struct efi_extract_callbacks *cb,
+ unsigned char *input_data,
+ unsigned long input_len,
+ unsigned char *output,
+ unsigned long output_len)
+{
+ extern char boot_heap[BOOT_HEAP_SIZE];
+
+ free_mem_ptr = (unsigned long)boot_heap; /* Heap */
+ free_mem_end_ptr = (unsigned long)boot_heap + BOOT_HEAP_SIZE;
+
+ init_console_func(cb->putstr, cb->puthex);
+ kernel_add_identity_map = cb->map_range;
+
+ return do_extract_kernel(rmode, input_data,
+ input_len, output, output_len);
+}
+
+
+
+
void fortify_panic(const char *name)
{
error("detected buffer overflow");
diff --git a/arch/x86/boot/compressed/misc.h b/arch/x86/boot/compressed/misc.h
index 0076b2845b4b..379c4a3ca7dd 100644
--- a/arch/x86/boot/compressed/misc.h
+++ b/arch/x86/boot/compressed/misc.h
@@ -26,6 +26,7 @@
#include <asm/boot.h>
#include <asm/bootparam.h>
#include <asm/desc_defs.h>
+#include <asm/shared/extract.h>
#include "tdx.h"
diff --git a/arch/x86/include/asm/shared/extract.h b/arch/x86/include/asm/shared/extract.h
new file mode 100644
index 000000000000..ebbc93333c74
--- /dev/null
+++ b/arch/x86/include/asm/shared/extract.h
@@ -0,0 +1,27 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef ASM_SHARED_EXTRACT_H
+#define ASM_SHARED_EXTRACT_H
+
+#include <asm/bootparam.h>
+
+#define MAP_WRITE 0x02 /* Writable memory */
+#define MAP_EXEC 0x04 /* Executable memory */
+#define MAP_ALLOC 0x10 /* Range needs to be allocated */
+#define MAP_PROTECT 0x20 /* Set exact memory attributes for memory range */
+
+struct efi_extract_callbacks {
+ void (*putstr)(const char *msg);
+ void (*puthex)(unsigned long x);
+ unsigned long (*map_range)(unsigned long start,
+ unsigned long end,
+ unsigned int flags);
+};
+
+void *efi_extract_kernel(struct boot_params *rmode,
+ struct efi_extract_callbacks *cb,
+ unsigned char *input_data,
+ unsigned long input_len,
+ unsigned char *output,
+ unsigned long output_len);
+
+#endif /* ASM_SHARED_EXTRACT_H */
--
2.37.4
Ensure WP bit to be set to prevent boot code from writing to
non-writable memory pages.
Signed-off-by: Evgeniy Baskov <[email protected]>
---
arch/x86/boot/compressed/head_64.S | 5 ++---
1 file changed, 2 insertions(+), 3 deletions(-)
diff --git a/arch/x86/boot/compressed/head_64.S b/arch/x86/boot/compressed/head_64.S
index d33f060900d2..2a4372b84fc8 100644
--- a/arch/x86/boot/compressed/head_64.S
+++ b/arch/x86/boot/compressed/head_64.S
@@ -684,9 +684,8 @@ SYM_CODE_START(trampoline_32bit_src)
pushl $__KERNEL_CS
pushl %eax
- /* Enable paging again. */
- movl %cr0, %eax
- btsl $X86_CR0_PG_BIT, %eax
+ /* Enable paging and set CR0 to known state (this also sets WP flag) */
+ movl $CR0_STATE, %eax
movl %eax, %cr0
lret
--
2.37.4
Explicitly change sections memory attributes in efi_pe_entry in case
of incorrect EFI implementations and to reduce access rights to
compressed kernel blob. By default it is set executable due to
restriction in maximum number of sections that can fit before zero
page.
Signed-off-by: Evgeniy Baskov <[email protected]>
---
drivers/firmware/efi/libstub/x86-stub.c | 56 +++++++++++++++++++++++++
1 file changed, 56 insertions(+)
diff --git a/drivers/firmware/efi/libstub/x86-stub.c b/drivers/firmware/efi/libstub/x86-stub.c
index 4d9588d33479..d9bb9125d518 100644
--- a/drivers/firmware/efi/libstub/x86-stub.c
+++ b/drivers/firmware/efi/libstub/x86-stub.c
@@ -27,6 +27,12 @@ const efi_dxe_services_table_t *efi_dxe_table;
extern u32 image_offset;
static efi_loaded_image_t *image = NULL;
+extern char _head[], _ehead[];
+extern char _compressed[], _ecompressed[];
+extern char _text[], _etext[];
+extern char _rodata[], _erodata[];
+extern char _data[];
+
static efi_status_t
preserve_pci_rom_image(efi_pci_io_protocol_t *pci, struct pci_setup_rom **__rom)
{
@@ -343,6 +349,54 @@ static void __noreturn efi_exit(efi_handle_t handle, efi_status_t status)
asm("hlt");
}
+
+/*
+ * Manually setup memory protection attributes for each ELF section
+ * since we cannot do it properly by using PE sections.
+ */
+static void setup_sections_memory_protection(void *image_base,
+ unsigned long init_size)
+{
+#ifdef CONFIG_EFI_DXE_MEM_ATTRIBUTES
+ efi_dxe_table = get_efi_config_table(EFI_DXE_SERVICES_TABLE_GUID);
+
+ if (!efi_dxe_table ||
+ efi_dxe_table->hdr.signature != EFI_DXE_SERVICES_TABLE_SIGNATURE) {
+ efi_warn("Unable to locate EFI DXE services table\n");
+ efi_dxe_table = NULL;
+ return;
+ }
+
+ /* .setup [image_base, _head] */
+ efi_adjust_memory_range_protection((unsigned long)image_base,
+ (unsigned long)_head - (unsigned long)image_base,
+ EFI_MEMORY_RO | EFI_MEMORY_XP);
+ /* .head.text [_head, _ehead] */
+ efi_adjust_memory_range_protection((unsigned long)_head,
+ (unsigned long)_ehead - (unsigned long)_head,
+ EFI_MEMORY_RO);
+ /* .rodata..compressed [_compressed, _ecompressed] */
+ efi_adjust_memory_range_protection((unsigned long)_compressed,
+ (unsigned long)_ecompressed - (unsigned long)_compressed,
+ EFI_MEMORY_RO | EFI_MEMORY_XP);
+ /* .text [_text, _etext] */
+ efi_adjust_memory_range_protection((unsigned long)_text,
+ (unsigned long)_etext - (unsigned long)_text,
+ EFI_MEMORY_RO);
+ /* .rodata [_rodata, _erodata] */
+ efi_adjust_memory_range_protection((unsigned long)_rodata,
+ (unsigned long)_erodata - (unsigned long)_rodata,
+ EFI_MEMORY_RO | EFI_MEMORY_XP);
+ /* .data, .bss [_data, image_base + init_size] */
+ efi_adjust_memory_range_protection((unsigned long)_data,
+ (unsigned long)image_base + init_size - (unsigned long)_rodata,
+ EFI_MEMORY_XP);
+#else
+ (void)image_base;
+ (void)init_size;
+#endif
+}
+
void __noreturn efi_stub_entry(efi_handle_t handle,
efi_system_table_t *sys_table_arg,
struct boot_params *boot_params);
@@ -396,6 +450,8 @@ efi_status_t __efiapi efi_pe_entry(efi_handle_t handle,
memcpy(&hdr->jump, image_base + 0x1000,
sizeof(struct setup_header) - offsetof(struct setup_header, jump));
+ setup_sections_memory_protection(image_base, hdr->init_size);
+
/*
* Fill out some of the header fields ourselves because the
* EFI firmware loader doesn't load the first sector.
--
2.37.4
Add EFI_MEMORY_ATTRIBUTE_PROTOCOL as preferred alternative to DXE
services for changing memory attributes in the EFISTUB.
Use DXE services only as a fallback in case aforementioned protocol
is not supported by UEFI implementation.
Move DXE services initialization code closer to the place they are used
to match EFI_MEMORY_ATTRIBUTE_PROTOCOL initialization code.
Signed-off-by: Evgeniy Baskov <[email protected]>
---
drivers/firmware/efi/libstub/mem.c | 168 ++++++++++++++++++------
drivers/firmware/efi/libstub/x86-stub.c | 17 ---
2 files changed, 128 insertions(+), 57 deletions(-)
diff --git a/drivers/firmware/efi/libstub/mem.c b/drivers/firmware/efi/libstub/mem.c
index cdf1e6fb6430..35acec241dd3 100644
--- a/drivers/firmware/efi/libstub/mem.c
+++ b/drivers/firmware/efi/libstub/mem.c
@@ -5,6 +5,9 @@
#include "efistub.h"
+const efi_dxe_services_table_t *efi_dxe_table;
+efi_memory_attribute_protocol_t *efi_mem_attrib_proto;
+
/**
* efi_get_memory_map() - get memory map
* @map: pointer to memory map pointer to which to assign the
@@ -126,66 +129,47 @@ void efi_free(unsigned long size, unsigned long addr)
efi_bs_call(free_pages, addr, nr_pages);
}
-/**
- * efi_adjust_memory_range_protection() - change memory range protection attributes
- * @start: memory range start address
- * @size: memory range size
- *
- * Actual memory range for which memory attributes are modified is
- * the smallest ranged with start address and size aligned to EFI_PAGE_SIZE
- * that includes [start, start + size].
- *
- * @return: status code
- */
-efi_status_t efi_adjust_memory_range_protection(unsigned long start,
- unsigned long size,
- unsigned long attributes)
+static void retrieve_dxe_table(void)
+{
+ efi_dxe_table = get_efi_config_table(EFI_DXE_SERVICES_TABLE_GUID);
+ if (efi_dxe_table &&
+ efi_dxe_table->hdr.signature != EFI_DXE_SERVICES_TABLE_SIGNATURE) {
+ efi_warn("Ignoring DXE services table: invalid signature\n");
+ efi_dxe_table = NULL;
+ }
+}
+
+static efi_status_t adjust_mem_attrib_dxe(efi_physical_addr_t rounded_start,
+ efi_physical_addr_t rounded_end,
+ unsigned long attributes)
{
efi_status_t status;
efi_gcd_memory_space_desc_t desc;
- efi_physical_addr_t end, next;
- efi_physical_addr_t rounded_start, rounded_end;
+ efi_physical_addr_t end, next, start;
efi_physical_addr_t unprotect_start, unprotect_size;
- if (efi_dxe_table == NULL)
- return EFI_UNSUPPORTED;
+ if (!efi_dxe_table) {
+ retrieve_dxe_table();
- /*
- * This function should not be used to modify attributes
- * other than writable/executable.
- */
-
- if ((attributes & ~(EFI_MEMORY_RO | EFI_MEMORY_XP)) != 0)
- return EFI_INVALID_PARAMETER;
-
- /*
- * Disallow simultaniously executable and writable memory
- * to inforce W^X policy if direct extraction code is enabled.
- */
-
- if ((attributes & (EFI_MEMORY_RO | EFI_MEMORY_XP)) == 0) {
- efi_warn("W^X violation at [%08lx,%08lx]\n",
- (unsigned long)rounded_start,
- (unsigned long)rounded_end);
+ if (!efi_dxe_table)
+ return EFI_UNSUPPORTED;
}
- rounded_start = rounddown(start, EFI_PAGE_SIZE);
- rounded_end = roundup(start + size, EFI_PAGE_SIZE);
-
/*
* Don't modify memory region attributes, they are
* already suitable, to lower the possibility to
* encounter firmware bugs.
*/
- for (end = start + size; start < end; start = next) {
+
+ for (start = rounded_start, end = rounded_end; start < end; start = next) {
status = efi_dxe_call(get_memory_space_descriptor,
start, &desc);
if (status != EFI_SUCCESS) {
efi_warn("Unable to get memory descriptor at %lx\n",
- start);
+ (unsigned long)start);
return status;
}
@@ -227,3 +211,107 @@ efi_status_t efi_adjust_memory_range_protection(unsigned long start,
return EFI_SUCCESS;
}
+
+static void retrieve_memory_attributes_proto(void)
+{
+ efi_status_t status;
+ efi_guid_t guid = EFI_MEMORY_ATTRIBUTE_PROTOCOL_GUID;
+
+ status = efi_bs_call(locate_protocol, &guid, NULL,
+ (void **)&efi_mem_attrib_proto);
+ if (status != EFI_SUCCESS)
+ efi_mem_attrib_proto = NULL;
+}
+
+/**
+ * efi_adjust_memory_range_protection() - change memory range protection attributes
+ * @start: memory range start address
+ * @size: memory range size
+ *
+ * Actual memory range for which memory attributes are modified is
+ * the smallest ranged with start address and size aligned to EFI_PAGE_SIZE
+ * that includes [start, start + size].
+ *
+ * This function first attempts to use EFI_MEMORY_ATTRIBUTE_PROTOCOL,
+ * that is a part of UEFI Specification since version 2.10.
+ * If the protocol is unavailable it falls back to DXE services functions.
+ *
+ * @return: status code
+ */
+efi_status_t efi_adjust_memory_range_protection(unsigned long start,
+ unsigned long size,
+ unsigned long attributes)
+{
+ efi_status_t status;
+ efi_physical_addr_t rounded_start, rounded_end;
+ unsigned long attr_clear;
+
+ /*
+ * This function should not be used to modify attributes
+ * other than writable/executable.
+ */
+
+ if ((attributes & ~(EFI_MEMORY_RO | EFI_MEMORY_XP)) != 0)
+ return EFI_INVALID_PARAMETER;
+
+ /*
+ * Warn if requested to make memory simultaneously
+ * executable and writable to enforce W^X policy.
+ */
+
+ if ((attributes & (EFI_MEMORY_RO | EFI_MEMORY_XP)) == 0) {
+ efi_warn("W^X violation at [%08lx,%08lx]",
+ (unsigned long)rounded_start,
+ (unsigned long)rounded_end);
+ }
+
+ rounded_start = rounddown(start, EFI_PAGE_SIZE);
+ rounded_end = roundup(start + size, EFI_PAGE_SIZE);
+
+ if (!efi_mem_attrib_proto) {
+ retrieve_memory_attributes_proto();
+
+ /* Fall back to DXE services if unsupported */
+ if (!efi_mem_attrib_proto) {
+ return adjust_mem_attrib_dxe(rounded_start,
+ rounded_end,
+ attributes);
+ }
+ }
+
+ /*
+ * Unlike DXE services functions, EFI_MEMORY_ATTRIBUTE_PROTOCOL
+ * does not clear unset protection bit, so it needs to be cleared
+ * explcitly
+ */
+
+ attr_clear = ~attributes &
+ (EFI_MEMORY_RO | EFI_MEMORY_XP | EFI_MEMORY_RP);
+
+ status = efi_call_proto(efi_mem_attrib_proto,
+ clear_memory_attributes,
+ rounded_start,
+ rounded_end - rounded_start,
+ attr_clear);
+ if (status != EFI_SUCCESS) {
+ efi_warn("Failed to clear memory attributes at [%08lx,%08lx]: %lx",
+ (unsigned long)rounded_start,
+ (unsigned long)rounded_end,
+ status);
+ return status;
+ }
+
+ status = efi_call_proto(efi_mem_attrib_proto,
+ set_memory_attributes,
+ rounded_start,
+ rounded_end - rounded_start,
+ attributes);
+ if (status != EFI_SUCCESS) {
+ efi_warn("Failed to set memory attributes at [%08lx,%08lx]: %lx",
+ (unsigned long)rounded_start,
+ (unsigned long)rounded_end,
+ status);
+ }
+
+ return status;
+}
diff --git a/drivers/firmware/efi/libstub/x86-stub.c b/drivers/firmware/efi/libstub/x86-stub.c
index d9bb9125d518..95a69c37518e 100644
--- a/drivers/firmware/efi/libstub/x86-stub.c
+++ b/drivers/firmware/efi/libstub/x86-stub.c
@@ -23,7 +23,6 @@
#define MAXMEM_X86_64_4LEVEL (1ull << 46)
const efi_system_table_t *efi_system_table;
-const efi_dxe_services_table_t *efi_dxe_table;
extern u32 image_offset;
static efi_loaded_image_t *image = NULL;
@@ -358,15 +357,6 @@ static void setup_sections_memory_protection(void *image_base,
unsigned long init_size)
{
#ifdef CONFIG_EFI_DXE_MEM_ATTRIBUTES
- efi_dxe_table = get_efi_config_table(EFI_DXE_SERVICES_TABLE_GUID);
-
- if (!efi_dxe_table ||
- efi_dxe_table->hdr.signature != EFI_DXE_SERVICES_TABLE_SIGNATURE) {
- efi_warn("Unable to locate EFI DXE services table\n");
- efi_dxe_table = NULL;
- return;
- }
-
/* .setup [image_base, _head] */
efi_adjust_memory_range_protection((unsigned long)image_base,
(unsigned long)_head - (unsigned long)image_base,
@@ -736,13 +726,6 @@ asmlinkage unsigned long efi_main(efi_handle_t handle,
if (efi_system_table->hdr.signature != EFI_SYSTEM_TABLE_SIGNATURE)
efi_exit(handle, EFI_INVALID_PARAMETER);
- efi_dxe_table = get_efi_config_table(EFI_DXE_SERVICES_TABLE_GUID);
- if (efi_dxe_table &&
- efi_dxe_table->hdr.signature != EFI_DXE_SERVICES_TABLE_SIGNATURE) {
- efi_warn("Ignoring DXE services table: invalid signature\n");
- efi_dxe_table = NULL;
- }
-
#ifdef CONFIG_CMDLINE_BOOL
status = efi_parse_options(CONFIG_CMDLINE);
if (status != EFI_SUCCESS) {
--
2.37.4
Current identity mapping code only supports 2M and 1G pages.
4KB pages are desirable for better memory protection granularity
in compressed kernel code.
Change identity mapping code to support 4KB pages and
memory remapping with different attributes.
Signed-off-by: Evgeniy Baskov <[email protected]>
---
arch/x86/include/asm/init.h | 1 +
arch/x86/mm/ident_map.c | 185 +++++++++++++++++++++++++++++-------
2 files changed, 154 insertions(+), 32 deletions(-)
diff --git a/arch/x86/include/asm/init.h b/arch/x86/include/asm/init.h
index 5f1d3c421f68..a8277ee82c51 100644
--- a/arch/x86/include/asm/init.h
+++ b/arch/x86/include/asm/init.h
@@ -8,6 +8,7 @@ struct x86_mapping_info {
unsigned long page_flag; /* page flag for PMD or PUD entry */
unsigned long offset; /* ident mapping offset */
bool direct_gbpages; /* PUD level 1GB page support */
+ bool allow_4kpages; /* Allow more granular mappings with 4K pages */
unsigned long kernpg_flag; /* kernel pagetable flag override */
};
diff --git a/arch/x86/mm/ident_map.c b/arch/x86/mm/ident_map.c
index 968d7005f4a7..662e794a325d 100644
--- a/arch/x86/mm/ident_map.c
+++ b/arch/x86/mm/ident_map.c
@@ -4,24 +4,127 @@
* included by both the compressed kernel and the regular kernel.
*/
-static void ident_pmd_init(struct x86_mapping_info *info, pmd_t *pmd_page,
- unsigned long addr, unsigned long end)
+static void ident_pte_init(struct x86_mapping_info *info, pte_t *pte_page,
+ unsigned long addr, unsigned long end,
+ unsigned long flags)
{
- addr &= PMD_MASK;
- for (; addr < end; addr += PMD_SIZE) {
+ addr &= PAGE_MASK;
+ for (; addr < end; addr += PAGE_SIZE) {
+ pte_t *pte = pte_page + pte_index(addr);
+
+ set_pte(pte, __pte((addr - info->offset) | flags));
+ }
+}
+
+pte_t *ident_split_large_pmd(struct x86_mapping_info *info,
+ pmd_t *pmdp, unsigned long page_addr)
+{
+ unsigned long pmd_addr, page_flags;
+ pte_t *pte;
+
+ pte = (pte_t *)info->alloc_pgt_page(info->context);
+ if (!pte)
+ return NULL;
+
+ pmd_addr = page_addr & PMD_MASK;
+
+ /* Not a large page - clear PSE flag */
+ page_flags = pmd_flags(*pmdp) & ~_PSE;
+ ident_pte_init(info, pte, pmd_addr, pmd_addr + PMD_SIZE, page_flags);
+
+ return pte;
+}
+
+static int ident_pmd_init(struct x86_mapping_info *info, pmd_t *pmd_page,
+ unsigned long addr, unsigned long end,
+ unsigned long flags)
+{
+ unsigned long next;
+ bool new_table = 0;
+
+ for (; addr < end; addr = next) {
pmd_t *pmd = pmd_page + pmd_index(addr);
+ pte_t *pte;
- if (pmd_present(*pmd))
+ next = (addr & PMD_MASK) + PMD_SIZE;
+ if (next > end)
+ next = end;
+
+ /*
+ * Use 2M pages if 4k pages are not allowed or
+ * we are not mapping extra, i.e. address and size are aligned.
+ */
+
+ if (!info->allow_4kpages ||
+ (!(addr & ~PMD_MASK) && next == addr + PMD_SIZE)) {
+
+ pmd_t pmdval;
+
+ addr &= PMD_MASK;
+ pmdval = __pmd((addr - info->offset) | flags | _PSE);
+ set_pmd(pmd, pmdval);
continue;
+ }
+
+ /*
+ * If currently mapped page is large, we need to split it.
+ * The case when we don't can remap 2M page to 2M page
+ * with different flags is already covered above.
+ *
+ * If there's nothing mapped to desired address,
+ * we need to allocate new page table.
+ */
- set_pmd(pmd, __pmd((addr - info->offset) | info->page_flag));
+ if (pmd_large(*pmd)) {
+ pte = ident_split_large_pmd(info, pmd, addr);
+ new_table = 1;
+ } else if (!pmd_present(*pmd)) {
+ pte = (pte_t *)info->alloc_pgt_page(info->context);
+ new_table = 1;
+ } else {
+ pte = pte_offset_kernel(pmd, 0);
+ new_table = 0;
+ }
+
+ if (!pte)
+ return -ENOMEM;
+
+ ident_pte_init(info, pte, addr, next, flags);
+
+ if (new_table)
+ set_pmd(pmd, __pmd(__pa(pte) | info->kernpg_flag));
}
+
+ return 0;
}
+
+pmd_t *ident_split_large_pud(struct x86_mapping_info *info,
+ pud_t *pudp, unsigned long page_addr)
+{
+ unsigned long pud_addr, page_flags;
+ pmd_t *pmd;
+
+ pmd = (pmd_t *)info->alloc_pgt_page(info->context);
+ if (!pmd)
+ return NULL;
+
+ pud_addr = page_addr & PUD_MASK;
+
+ /* Not a large page - clear PSE flag */
+ page_flags = pud_flags(*pudp) & ~_PSE;
+ ident_pmd_init(info, pmd, pud_addr, pud_addr + PUD_SIZE, page_flags);
+
+ return pmd;
+}
+
+
static int ident_pud_init(struct x86_mapping_info *info, pud_t *pud_page,
unsigned long addr, unsigned long end)
{
unsigned long next;
+ bool new_table = 0;
+ int result;
for (; addr < end; addr = next) {
pud_t *pud = pud_page + pud_index(addr);
@@ -31,28 +134,39 @@ static int ident_pud_init(struct x86_mapping_info *info, pud_t *pud_page,
if (next > end)
next = end;
+ /* Use 1G pages only if forced, even if they are supported. */
if (info->direct_gbpages) {
pud_t pudval;
-
- if (pud_present(*pud))
- continue;
+ unsigned long flags;
addr &= PUD_MASK;
- pudval = __pud((addr - info->offset) | info->page_flag);
+ flags = info->page_flag | _PSE;
+ pudval = __pud((addr - info->offset) | flags);
+
set_pud(pud, pudval);
continue;
}
- if (pud_present(*pud)) {
+ if (pud_large(*pud)) {
+ pmd = ident_split_large_pud(info, pud, addr);
+ new_table = 1;
+ } else if (!pud_present(*pud)) {
+ pmd = (pmd_t *)info->alloc_pgt_page(info->context);
+ new_table = 1;
+ } else {
pmd = pmd_offset(pud, 0);
- ident_pmd_init(info, pmd, addr, next);
- continue;
+ new_table = 0;
}
- pmd = (pmd_t *)info->alloc_pgt_page(info->context);
+
if (!pmd)
return -ENOMEM;
- ident_pmd_init(info, pmd, addr, next);
- set_pud(pud, __pud(__pa(pmd) | info->kernpg_flag));
+
+ result = ident_pmd_init(info, pmd, addr, next, info->page_flag);
+ if (result)
+ return result;
+
+ if (new_table)
+ set_pud(pud, __pud(__pa(pmd) | info->kernpg_flag));
}
return 0;
@@ -63,6 +177,7 @@ static int ident_p4d_init(struct x86_mapping_info *info, p4d_t *p4d_page,
{
unsigned long next;
int result;
+ bool new_table = 0;
for (; addr < end; addr = next) {
p4d_t *p4d = p4d_page + p4d_index(addr);
@@ -72,15 +187,14 @@ static int ident_p4d_init(struct x86_mapping_info *info, p4d_t *p4d_page,
if (next > end)
next = end;
- if (p4d_present(*p4d)) {
+ if (!p4d_present(*p4d)) {
+ pud = (pud_t *)info->alloc_pgt_page(info->context);
+ new_table = 1;
+ } else {
pud = pud_offset(p4d, 0);
- result = ident_pud_init(info, pud, addr, next);
- if (result)
- return result;
-
- continue;
+ new_table = 0;
}
- pud = (pud_t *)info->alloc_pgt_page(info->context);
+
if (!pud)
return -ENOMEM;
@@ -88,19 +202,22 @@ static int ident_p4d_init(struct x86_mapping_info *info, p4d_t *p4d_page,
if (result)
return result;
- set_p4d(p4d, __p4d(__pa(pud) | info->kernpg_flag));
+ if (new_table)
+ set_p4d(p4d, __p4d(__pa(pud) | info->kernpg_flag));
}
return 0;
}
-int kernel_ident_mapping_init(struct x86_mapping_info *info, pgd_t *pgd_page,
- unsigned long pstart, unsigned long pend)
+int kernel_ident_mapping_init(struct x86_mapping_info *info,
+ pgd_t *pgd_page, unsigned long pstart,
+ unsigned long pend)
{
unsigned long addr = pstart + info->offset;
unsigned long end = pend + info->offset;
unsigned long next;
int result;
+ bool new_table;
/* Set the default pagetable flags if not supplied */
if (!info->kernpg_flag)
@@ -117,20 +234,24 @@ int kernel_ident_mapping_init(struct x86_mapping_info *info, pgd_t *pgd_page,
if (next > end)
next = end;
- if (pgd_present(*pgd)) {
+ if (!pgd_present(*pgd)) {
+ p4d = (p4d_t *)info->alloc_pgt_page(info->context);
+ new_table = 1;
+ } else {
p4d = p4d_offset(pgd, 0);
- result = ident_p4d_init(info, p4d, addr, next);
- if (result)
- return result;
- continue;
+ new_table = 0;
}
- p4d = (p4d_t *)info->alloc_pgt_page(info->context);
if (!p4d)
return -ENOMEM;
+
result = ident_p4d_init(info, p4d, addr, next);
if (result)
return result;
+
+ if (!new_table)
+ continue;
+
if (pgtable_l5_enabled()) {
set_pgd(pgd, __pgd(__pa(p4d) | info->kernpg_flag));
} else {
--
2.37.4
efi_adjust_memory_range_protection() can be useful outside x86-stub.c.
Move it to mem.c, where memory related code resides and make it
non-static.
Change its behavior to setup exact attributes and disallow making
memory regions readable and writable simultaneously for supported
configurations.
Signed-off-by: Evgeniy Baskov <[email protected]>
---
drivers/firmware/efi/libstub/efistub.h | 4 +
drivers/firmware/efi/libstub/mem.c | 102 ++++++++++++++++++++++++
drivers/firmware/efi/libstub/x86-stub.c | 66 ++-------------
3 files changed, 112 insertions(+), 60 deletions(-)
diff --git a/drivers/firmware/efi/libstub/efistub.h b/drivers/firmware/efi/libstub/efistub.h
index a30fb5d8ef05..63f5157341fe 100644
--- a/drivers/firmware/efi/libstub/efistub.h
+++ b/drivers/firmware/efi/libstub/efistub.h
@@ -917,6 +917,10 @@ efi_status_t efi_relocate_kernel(unsigned long *image_addr,
unsigned long alignment,
unsigned long min_addr);
+efi_status_t efi_adjust_memory_range_protection(unsigned long start,
+ unsigned long size,
+ unsigned long attributes);
+
efi_status_t efi_parse_options(char const *cmdline);
void efi_parse_option_graphics(char *option);
diff --git a/drivers/firmware/efi/libstub/mem.c b/drivers/firmware/efi/libstub/mem.c
index 45841ef55a9f..cdf1e6fb6430 100644
--- a/drivers/firmware/efi/libstub/mem.c
+++ b/drivers/firmware/efi/libstub/mem.c
@@ -125,3 +125,105 @@ void efi_free(unsigned long size, unsigned long addr)
nr_pages = round_up(size, EFI_ALLOC_ALIGN) / EFI_PAGE_SIZE;
efi_bs_call(free_pages, addr, nr_pages);
}
+
+/**
+ * efi_adjust_memory_range_protection() - change memory range protection attributes
+ * @start: memory range start address
+ * @size: memory range size
+ *
+ * Actual memory range for which memory attributes are modified is
+ * the smallest ranged with start address and size aligned to EFI_PAGE_SIZE
+ * that includes [start, start + size].
+ *
+ * @return: status code
+ */
+efi_status_t efi_adjust_memory_range_protection(unsigned long start,
+ unsigned long size,
+ unsigned long attributes)
+{
+ efi_status_t status;
+ efi_gcd_memory_space_desc_t desc;
+ efi_physical_addr_t end, next;
+ efi_physical_addr_t rounded_start, rounded_end;
+ efi_physical_addr_t unprotect_start, unprotect_size;
+
+ if (efi_dxe_table == NULL)
+ return EFI_UNSUPPORTED;
+
+ /*
+ * This function should not be used to modify attributes
+ * other than writable/executable.
+ */
+
+ if ((attributes & ~(EFI_MEMORY_RO | EFI_MEMORY_XP)) != 0)
+ return EFI_INVALID_PARAMETER;
+
+ /*
+ * Disallow simultaniously executable and writable memory
+ * to inforce W^X policy if direct extraction code is enabled.
+ */
+
+ if ((attributes & (EFI_MEMORY_RO | EFI_MEMORY_XP)) == 0) {
+ efi_warn("W^X violation at [%08lx,%08lx]\n",
+ (unsigned long)rounded_start,
+ (unsigned long)rounded_end);
+ }
+
+ rounded_start = rounddown(start, EFI_PAGE_SIZE);
+ rounded_end = roundup(start + size, EFI_PAGE_SIZE);
+
+ /*
+ * Don't modify memory region attributes, they are
+ * already suitable, to lower the possibility to
+ * encounter firmware bugs.
+ */
+
+ for (end = start + size; start < end; start = next) {
+
+ status = efi_dxe_call(get_memory_space_descriptor,
+ start, &desc);
+
+ if (status != EFI_SUCCESS) {
+ efi_warn("Unable to get memory descriptor at %lx\n",
+ start);
+ return status;
+ }
+
+ next = desc.base_address + desc.length;
+
+ /*
+ * Only system memory is suitable for trampoline/kernel image
+ * placement, so only this type of memory needs its attributes
+ * to be modified.
+ */
+
+ if (desc.gcd_memory_type != EfiGcdMemoryTypeSystemMemory) {
+ efi_warn("Attempted to change protection of special memory range\n");
+ return EFI_UNSUPPORTED;
+ }
+
+ if (((desc.attributes ^ attributes) &
+ (EFI_MEMORY_RO | EFI_MEMORY_XP)) == 0)
+ continue;
+
+ desc.attributes &= ~(EFI_MEMORY_RO | EFI_MEMORY_XP);
+ desc.attributes |= attributes;
+
+ unprotect_start = max(rounded_start, desc.base_address);
+ unprotect_size = min(rounded_end, next) - unprotect_start;
+
+ status = efi_dxe_call(set_memory_space_attributes,
+ unprotect_start, unprotect_size,
+ desc.attributes);
+
+ if (status != EFI_SUCCESS) {
+ efi_warn("Unable to unprotect memory range [%08lx,%08lx]: %lx\n",
+ (unsigned long)unprotect_start,
+ (unsigned long)(unprotect_start + unprotect_size),
+ status);
+ return status;
+ }
+ }
+
+ return EFI_SUCCESS;
+}
diff --git a/drivers/firmware/efi/libstub/x86-stub.c b/drivers/firmware/efi/libstub/x86-stub.c
index 33a7811e12c6..2fddb88613cd 100644
--- a/drivers/firmware/efi/libstub/x86-stub.c
+++ b/drivers/firmware/efi/libstub/x86-stub.c
@@ -212,61 +212,6 @@ static void retrieve_apple_device_properties(struct boot_params *boot_params)
}
}
-static void
-adjust_memory_range_protection(unsigned long start, unsigned long size)
-{
- efi_status_t status;
- efi_gcd_memory_space_desc_t desc;
- unsigned long end, next;
- unsigned long rounded_start, rounded_end;
- unsigned long unprotect_start, unprotect_size;
-
- if (efi_dxe_table == NULL)
- return;
-
- rounded_start = rounddown(start, EFI_PAGE_SIZE);
- rounded_end = roundup(start + size, EFI_PAGE_SIZE);
-
- /*
- * Don't modify memory region attributes, they are
- * already suitable, to lower the possibility to
- * encounter firmware bugs.
- */
-
- for (end = start + size; start < end; start = next) {
-
- status = efi_dxe_call(get_memory_space_descriptor, start, &desc);
-
- if (status != EFI_SUCCESS)
- return;
-
- next = desc.base_address + desc.length;
-
- /*
- * Only system memory is suitable for trampoline/kernel image placement,
- * so only this type of memory needs its attributes to be modified.
- */
-
- if (desc.gcd_memory_type != EfiGcdMemoryTypeSystemMemory ||
- (desc.attributes & (EFI_MEMORY_RO | EFI_MEMORY_XP)) == 0)
- continue;
-
- unprotect_start = max(rounded_start, (unsigned long)desc.base_address);
- unprotect_size = min(rounded_end, next) - unprotect_start;
-
- status = efi_dxe_call(set_memory_space_attributes,
- unprotect_start, unprotect_size,
- EFI_MEMORY_WB);
-
- if (status != EFI_SUCCESS) {
- efi_warn("Unable to unprotect memory range [%08lx,%08lx]: %lx\n",
- unprotect_start,
- unprotect_start + unprotect_size,
- status);
- }
- }
-}
-
/*
* Trampoline takes 2 pages and can be loaded in first megabyte of memory
* with its end placed between 128k and 640k where BIOS might start.
@@ -290,12 +235,12 @@ setup_memory_protection(unsigned long image_base, unsigned long image_size)
* and relocated kernel image.
*/
- adjust_memory_range_protection(TRAMPOLINE_PLACEMENT_BASE,
- TRAMPOLINE_PLACEMENT_SIZE);
+ efi_adjust_memory_range_protection(TRAMPOLINE_PLACEMENT_BASE,
+ TRAMPOLINE_PLACEMENT_SIZE, 0);
#ifdef CONFIG_64BIT
if (image_base != (unsigned long)startup_32)
- adjust_memory_range_protection(image_base, image_size);
+ efi_adjust_memory_range_protection(image_base, image_size, 0);
#else
/*
* Clear protection flags on a whole range of possible
@@ -305,8 +250,9 @@ setup_memory_protection(unsigned long image_base, unsigned long image_size)
* need to remove possible protection on relocated image
* itself disregarding further relocations.
*/
- adjust_memory_range_protection(LOAD_PHYSICAL_ADDR,
- KERNEL_IMAGE_SIZE - LOAD_PHYSICAL_ADDR);
+ efi_adjust_memory_range_protection(LOAD_PHYSICAL_ADDR,
+ KERNEL_IMAGE_SIZE - LOAD_PHYSICAL_ADDR,
+ 0);
#endif
}
--
2.37.4
When allocating trampoline from libstub trampoline allocation is
performed separately, so it needs to be skipped.
Split trampoline initialization and allocation code into two
functions to make them invokable separately.
Signed-off-by: Evgeniy Baskov <[email protected]>
---
arch/x86/boot/compressed/pgtable_64.c | 73 +++++++++++++++++----------
1 file changed, 46 insertions(+), 27 deletions(-)
diff --git a/arch/x86/boot/compressed/pgtable_64.c b/arch/x86/boot/compressed/pgtable_64.c
index c7cf5a1059a8..1f7169248612 100644
--- a/arch/x86/boot/compressed/pgtable_64.c
+++ b/arch/x86/boot/compressed/pgtable_64.c
@@ -106,12 +106,8 @@ static unsigned long find_trampoline_placement(void)
return bios_start - TRAMPOLINE_32BIT_SIZE;
}
-struct paging_config paging_prepare(void *rmode)
+bool trampoline_pgtable_init(struct boot_params *boot_params)
{
- struct paging_config paging_config = {};
-
- /* Initialize boot_params. Required for cmdline_find_option_bool(). */
- boot_params = rmode;
/*
* Check if LA57 is desired and supported.
@@ -125,26 +121,10 @@ struct paging_config paging_prepare(void *rmode)
*
* That's substitute for boot_cpu_has() in early boot code.
*/
- if (IS_ENABLED(CONFIG_X86_5LEVEL) &&
- !cmdline_find_option_bool("no5lvl") &&
- native_cpuid_eax(0) >= 7 &&
- (native_cpuid_ecx(7) & (1 << (X86_FEATURE_LA57 & 31)))) {
- paging_config.l5_required = 1;
- }
-
- paging_config.trampoline_start = find_trampoline_placement();
-
- trampoline_32bit = (unsigned long *)paging_config.trampoline_start;
-
- /* Preserve trampoline memory */
- memcpy(trampoline_save, trampoline_32bit, TRAMPOLINE_32BIT_SIZE);
-
- /* Clear trampoline memory first */
- memset(trampoline_32bit, 0, TRAMPOLINE_32BIT_SIZE);
-
- /* Copy trampoline code in place */
- memcpy(trampoline_32bit + TRAMPOLINE_32BIT_CODE_OFFSET / sizeof(unsigned long),
- &trampoline_32bit_src, TRAMPOLINE_32BIT_CODE_SIZE);
+ bool l5_required = IS_ENABLED(CONFIG_X86_5LEVEL) &&
+ !cmdline_find_option_bool("no5lvl") &&
+ native_cpuid_eax(0) >= 7 &&
+ (native_cpuid_ecx(7) & (1 << (X86_FEATURE_LA57 & 31)));
/*
* The code below prepares page table in trampoline memory.
@@ -160,10 +140,10 @@ struct paging_config paging_prepare(void *rmode)
* We are not going to use the page table in trampoline memory if we
* are already in the desired paging mode.
*/
- if (paging_config.l5_required == !!(native_read_cr4() & X86_CR4_LA57))
+ if (l5_required == !!(native_read_cr4() & X86_CR4_LA57))
goto out;
- if (paging_config.l5_required) {
+ if (l5_required) {
/*
* For 4- to 5-level paging transition, set up current CR3 as
* the first and the only entry in a new top-level page table.
@@ -185,6 +165,45 @@ struct paging_config paging_prepare(void *rmode)
(void *)src, PAGE_SIZE);
}
+out:
+ return l5_required;
+}
+
+struct paging_config paging_prepare(void *rmode)
+{
+ struct paging_config paging_config = {};
+ bool early_trampoline_alloc = 0;
+
+ /* Initialize boot_params. Required for cmdline_find_option_bool(). */
+ boot_params = rmode;
+
+ /*
+ * We only need to find trampoline placement, if we have
+ * not already done it from libstub.
+ */
+
+ paging_config.trampoline_start = find_trampoline_placement();
+ trampoline_32bit = (unsigned long *)paging_config.trampoline_start;
+ early_trampoline_alloc = 0;
+
+ /*
+ * Preserve trampoline memory.
+ * When trampoline is located in memory
+ * owned by us, i.e. allocated in EFISTUB,
+ * we don't care about previous contents
+ * of this memory so copying can also be skipped.
+ */
+ memcpy(trampoline_save, trampoline_32bit, TRAMPOLINE_32BIT_SIZE);
+
+ /* Clear trampoline memory first */
+ memset(trampoline_32bit, 0, TRAMPOLINE_32BIT_SIZE);
+
+ /* Copy trampoline code in place */
+ memcpy(trampoline_32bit + TRAMPOLINE_32BIT_CODE_OFFSET / sizeof(unsigned long),
+ &trampoline_32bit_src, TRAMPOLINE_32BIT_CODE_SIZE);
+
+ paging_config.l5_required = trampoline_pgtable_init(boot_params);
+
out:
return paging_config;
}
--
2.37.4
Currently kernel image is not fully compliant PE image, so it may
fail to boot with stricter implementations of UEFI PE loaders.
Set minimal alignments and sizes specified by PE documentation [1]
referenced by UEFI specification [2]. Align PE header to 8 bytes.
Generate PE sections dynamically. This simplifies code, since with
current implementation all of the sections needs to be defined in
header.S, where most section header fields do not hold valid values,
except for their names. Before the change, it also held flags,
but now flags depend on kernel configuration and it is simpler
to set them from build.c too.
Setup sections protection. Since we cannot fit every needed section,
set a part of protection flags dynamically during initialization.
This step is omitted if CONFIG_EFI_DXE_MEM_ATTRIBUTES is not set.
[1] https://download.microsoft.com/download/9/c/5/9c5b2167-8017-4bae-9fde-d599bac8184a/pecoff_v83.docx
[2] https://uefi.org/sites/default/files/resources/UEFI_Spec_2_9_2021_03_18.pdf
Signed-off-by: Evgeniy Baskov <[email protected]>
---
arch/x86/boot/Makefile | 2 +-
arch/x86/boot/header.S | 96 +--------
arch/x86/boot/tools/build.c | 258 +++++++++++++++---------
drivers/firmware/efi/libstub/x86-stub.c | 7 +-
4 files changed, 175 insertions(+), 188 deletions(-)
diff --git a/arch/x86/boot/Makefile b/arch/x86/boot/Makefile
index 9860ca5979f8..7b4bdd926b10 100644
--- a/arch/x86/boot/Makefile
+++ b/arch/x86/boot/Makefile
@@ -91,7 +91,7 @@ $(obj)/vmlinux.bin: $(obj)/compressed/vmlinux FORCE
SETUP_OBJS = $(addprefix $(obj)/,$(setup-y))
-sed-zoffset := -e 's/^\([0-9a-fA-F]*\) [a-zA-Z] \(startup_32\|startup_64\|efi32_stub_entry\|efi64_stub_entry\|efi_pe_entry\|efi32_pe_entry\|input_data\|kernel_info\|_end\|_ehead\|_text\|z_.*\)$$/\#define ZO_\2 0x\1/p'
+sed-zoffset := -e 's/^\([0-9a-fA-F]*\) [a-zA-Z] \(startup_32\|startup_64\|efi32_stub_entry\|efi64_stub_entry\|efi_pe_entry\|efi32_pe_entry\|input_data\|kernel_info\|_end\|_ehead\|_text\|_rodata\|z_.*\)$$/\#define ZO_\2 0x\1/p'
quiet_cmd_zoffset = ZOFFSET $@
cmd_zoffset = $(NM) $< | sed -n $(sed-zoffset) > $@
diff --git a/arch/x86/boot/header.S b/arch/x86/boot/header.S
index e4de831b2f64..0d2f97607c86 100644
--- a/arch/x86/boot/header.S
+++ b/arch/x86/boot/header.S
@@ -93,6 +93,7 @@ bugger_off_msg:
.set bugger_off_msg_size, . - bugger_off_msg
#ifdef CONFIG_EFI_STUB
+ .align 8
pe_header:
.long PE_MAGIC
@@ -106,7 +107,7 @@ coff_header:
.set pe_opt_magic, PE_OPT_MAGIC_PE32PLUS
.word IMAGE_FILE_MACHINE_AMD64
#endif
- .word section_count # nr_sections
+ .word 0 # nr_sections
.long 0 # TimeDateStamp
.long 0 # PointerToSymbolTable
.long 1 # NumberOfSymbols
@@ -130,7 +131,7 @@ optional_header:
# Filled in by build.c
.long 0x0000 # AddressOfEntryPoint
- .long 0x0200 # BaseOfCode
+ .long 0x1000 # BaseOfCode
#ifdef CONFIG_X86_32
.long 0 # data
#endif
@@ -143,8 +144,8 @@ extra_header_fields:
#else
.quad image_base # ImageBase
#endif
- .long 0x20 # SectionAlignment
- .long 0x20 # FileAlignment
+ .long 0x1000 # SectionAlignment
+ .long 0x200 # FileAlignment
.word 0 # MajorOperatingSystemVersion
.word 0 # MinorOperatingSystemVersion
.word LINUX_EFISTUB_MAJOR_VERSION # MajorImageVersion
@@ -187,91 +188,14 @@ extra_header_fields:
.quad 0 # CertificationTable
.quad 0 # BaseRelocationTable
- # Section table
-section_table:
- #
- # The offset & size fields are filled in by build.c.
- #
- .ascii ".setup"
- .byte 0
- .byte 0
- .long 0
- .long 0x0 # startup_{32,64}
- .long 0 # Size of initialized data
- # on disk
- .long 0x0 # startup_{32,64}
- .long 0 # PointerToRelocations
- .long 0 # PointerToLineNumbers
- .word 0 # NumberOfRelocations
- .word 0 # NumberOfLineNumbers
- .long IMAGE_SCN_CNT_CODE | \
- IMAGE_SCN_MEM_READ | \
- IMAGE_SCN_MEM_EXECUTE | \
- IMAGE_SCN_ALIGN_16BYTES # Characteristics
-
- #
- # The EFI application loader requires a relocation section
- # because EFI applications must be relocatable. The .reloc
- # offset & size fields are filled in by build.c.
#
- .ascii ".reloc"
- .byte 0
- .byte 0
- .long 0
- .long 0
- .long 0 # SizeOfRawData
- .long 0 # PointerToRawData
- .long 0 # PointerToRelocations
- .long 0 # PointerToLineNumbers
- .word 0 # NumberOfRelocations
- .word 0 # NumberOfLineNumbers
- .long IMAGE_SCN_CNT_INITIALIZED_DATA | \
- IMAGE_SCN_MEM_READ | \
- IMAGE_SCN_MEM_DISCARDABLE | \
- IMAGE_SCN_ALIGN_1BYTES # Characteristics
-
-#ifdef CONFIG_EFI_MIXED
- #
- # The offset & size fields are filled in by build.c.
+ # Section table
+ # It is generated by build.c and here we just need
+ # to reserve some space for sections
#
- .asciz ".compat"
- .long 0
- .long 0x0
- .long 0 # Size of initialized data
- # on disk
- .long 0x0
- .long 0 # PointerToRelocations
- .long 0 # PointerToLineNumbers
- .word 0 # NumberOfRelocations
- .word 0 # NumberOfLineNumbers
- .long IMAGE_SCN_CNT_INITIALIZED_DATA | \
- IMAGE_SCN_MEM_READ | \
- IMAGE_SCN_MEM_DISCARDABLE | \
- IMAGE_SCN_ALIGN_1BYTES # Characteristics
-#endif
+section_table:
+ .fill 40*5, 1, 0
- #
- # The offset & size fields are filled in by build.c.
- #
- .ascii ".text"
- .byte 0
- .byte 0
- .byte 0
- .long 0
- .long 0x0 # startup_{32,64}
- .long 0 # Size of initialized data
- # on disk
- .long 0x0 # startup_{32,64}
- .long 0 # PointerToRelocations
- .long 0 # PointerToLineNumbers
- .word 0 # NumberOfRelocations
- .word 0 # NumberOfLineNumbers
- .long IMAGE_SCN_CNT_CODE | \
- IMAGE_SCN_MEM_READ | \
- IMAGE_SCN_MEM_EXECUTE | \
- IMAGE_SCN_ALIGN_16BYTES # Characteristics
-
- .set section_count, (. - section_table) / 40
#endif /* CONFIG_EFI_STUB */
# Kernel attributes; used by setup. This is part 1 of the
diff --git a/arch/x86/boot/tools/build.c b/arch/x86/boot/tools/build.c
index 9202645fec72..cd957a4f9d4e 100644
--- a/arch/x86/boot/tools/build.c
+++ b/arch/x86/boot/tools/build.c
@@ -61,8 +61,10 @@ uint8_t buf[SETUP_SECT_MAX*SECTOR_SIZE];
#ifdef CONFIG_EFI_MIXED
#define PECOFF_COMPAT_RESERVE 0x20
+#define COMPAT_SECTION_SIZE 0x8
#else
#define PECOFF_COMPAT_RESERVE 0x0
+#define COMPAT_SECTION_SIZE 0x0
#endif
#define RELOC_SECTION_SIZE 10
@@ -117,6 +119,7 @@ static unsigned long efi_pe_entry;
static unsigned long efi32_pe_entry;
static unsigned long kernel_info;
static unsigned long startup_64;
+static unsigned long _rodata;
static unsigned long _ehead;
static unsigned long _end;
@@ -258,84 +261,69 @@ static void *map_output_file(const char *path, size_t size)
#ifdef CONFIG_EFI_STUB
-static void update_pecoff_section_header_fields(char *section_name, uint32_t vma,
- uint32_t size, uint32_t datasz,
- uint32_t offset)
+static unsigned int reloc_offset;
+static unsigned int compat_offset;
+
+#define MAX_SECTIONS 5
+
+static void emit_pecoff_section(const char *section_name, unsigned int size,
+ unsigned int bss, unsigned int *file_offset,
+ unsigned int *mem_offset, uint32_t flags)
{
- unsigned int pe_header;
+ unsigned int section_memsz, section_filesz;
unsigned short num_sections;
+ struct pe_hdr *hdr = get_pe_header(buf);
struct section_header *section;
- struct pe_hdr *hdr = get_pe_header(buf);
num_sections = get_unaligned_le16(&hdr->sections);
- section = get_sections(buf);
+ if (num_sections >= MAX_SECTIONS)
+ die("Not enough space to generate all sections");
- while (num_sections > 0) {
- if (strncmp(section->name, section_name, 8) == 0) {
- /* section header size field */
- put_unaligned_le32(size, §ion->virtual_size);
+ section = get_sections(buf) + num_sections;
- /* section header vma field */
- put_unaligned_le32(vma, §ion->virtual_address);
+ if ((size & (FILE_ALIGNMENT - 1)) || (bss & (FILE_ALIGNMENT - 1)))
+ die("Section '%s' is improperly aligned", section_name);
- /* section header 'size of initialised data' field */
- put_unaligned_le32(datasz, §ion->raw_data_size);
+ section_memsz = round_up(size + bss, SECTION_ALIGNMENT);
+ section_filesz = round_up(size, FILE_ALIGNMENT);
- /* section header 'file offset' field */
- put_unaligned_le32(offset, §ion->data_addr);
+ /* Zero out all section fields */
+ memset(section, 0, sizeof(*section));
- break;
- }
- section++;
- num_sections--;
- }
-}
-
-static void update_pecoff_section_header(char *section_name, uint32_t offset, uint32_t size)
-{
- update_pecoff_section_header_fields(section_name, offset, size, size, offset);
-}
+ /* Section header size field */
+ memcpy(section->name, section_name, sizeof(section->name));
-static void update_pecoff_setup_and_reloc(unsigned int size)
-{
- uint32_t setup_offset = SECTOR_SIZE;
- uint32_t reloc_offset = size - PECOFF_RELOC_RESERVE - PECOFF_COMPAT_RESERVE;
-#ifdef CONFIG_EFI_MIXED
- uint32_t compat_offset = reloc_offset + PECOFF_RELOC_RESERVE;
-#endif
- uint32_t setup_size = reloc_offset - setup_offset;
+ put_unaligned_le32(section_memsz, §ion->virtual_size);
+ put_unaligned_le32(*mem_offset, §ion->virtual_address);
+ put_unaligned_le32(section_filesz, §ion->raw_data_size);
+ put_unaligned_le32(*file_offset, §ion->data_addr);
+ put_unaligned_le32(flags, §ion->flags);
- update_pecoff_section_header(".setup", setup_offset, setup_size);
- update_pecoff_section_header(".reloc", reloc_offset, PECOFF_RELOC_RESERVE);
+ put_unaligned_le16(num_sections + 1, &hdr->sections);
- /*
- * Modify .reloc section contents with a single entry. The
- * relocation is applied to offset 10 of the relocation section.
- */
- put_unaligned_le32(reloc_offset + RELOC_SECTION_SIZE, &buf[reloc_offset]);
- put_unaligned_le32(RELOC_SECTION_SIZE, &buf[reloc_offset + 4]);
+ *mem_offset += section_memsz;
+ *file_offset += section_filesz;
+}
-#ifdef CONFIG_EFI_MIXED
- update_pecoff_section_header(".compat", compat_offset, PECOFF_COMPAT_RESERVE);
+#define BASE_RVA 0x1000
- /*
- * Put the IA-32 machine type (0x14c) and the associated entry point
- * address in the .compat section, so loaders can figure out which other
- * execution modes this image supports.
- */
- buf[compat_offset] = 0x1;
- buf[compat_offset + 1] = 0x8;
- put_unaligned_le16(IMAGE_FILE_MACHINE_I386, &buf[compat_offset + 2]);
- put_unaligned_le32(efi32_pe_entry + size, &buf[compat_offset + 4]);
-#endif
-}
+static unsigned int text_rva;
-static unsigned int update_pecoff_sections(unsigned int text_start, unsigned int text_sz,
- unsigned int init_sz)
+static unsigned int update_pecoff_sections(unsigned int setup_size,
+ unsigned int file_size,
+ unsigned int init_size,
+ unsigned int text_size)
{
- unsigned int file_sz = text_start + text_sz;
- unsigned int bss_sz = init_sz - file_sz;
- pe_opt_hdr *hdr = get_pe_opt_header(buf);
+ /* First section starts at 512 byes, after PE header */
+ unsigned int mem_offset = BASE_RVA, file_offset = SECTOR_SIZE;
+ unsigned int compat_size, reloc_size, image_size;
+ unsigned int bss_size, text_rva_diff, reloc_rva;
+ pe_opt_hdr *opt_hdr = get_pe_opt_header(buf);
+ struct pe_hdr *hdr = get_pe_header(buf);
+ struct data_dirent *base_reloc;
+
+ if (get_unaligned_le32(&hdr->sections))
+ die("Some sections present in PE file");
/*
* The PE/COFF loader may load the image at an address which is
@@ -346,34 +334,122 @@ static unsigned int update_pecoff_sections(unsigned int text_start, unsigned int
* add slack to allow the buffer to be aligned within the declared size
* of the image.
*/
- bss_sz += CONFIG_PHYSICAL_ALIGN;
- init_sz += CONFIG_PHYSICAL_ALIGN;
+ init_size += CONFIG_PHYSICAL_ALIGN;
+ image_size = init_size;
+
+ reloc_size = round_up(RELOC_SECTION_SIZE, FILE_ALIGNMENT);
+ compat_size = round_up(COMPAT_SECTION_SIZE, FILE_ALIGNMENT);
+
+ /*
+ * Let's remove extra memory used by special sections
+ * and use it as a part of bss.
+ */
+ init_size -= round_up(reloc_size, SECTION_ALIGNMENT);
+ init_size -= round_up(compat_size, SECTION_ALIGNMENT);
+ if (init_size < file_size + setup_size) {
+ init_size = file_size + setup_size;
+ image_size += round_up(reloc_size, SECTION_ALIGNMENT);
+ image_size += round_up(compat_size, SECTION_ALIGNMENT);
+ }
/*
- * Size of code: Subtract the size of the first sector (512 bytes)
- * which includes the header.
+ * Update sections offsets.
+ * NOTE: Order is important
*/
- put_unaligned_le32(file_sz - SECTOR_SIZE + bss_sz, &hdr->text_size);
- /* Size of image */
- put_unaligned_le32(init_sz, &hdr->image_size);
+ bss_size = init_size - file_size - setup_size;
+
+ emit_pecoff_section(".setup", setup_size - SECTOR_SIZE, 0,
+ &file_offset, &mem_offset, SCN_RO |
+ IMAGE_SCN_CNT_INITIALIZED_DATA);
+
+ text_rva_diff = mem_offset - file_offset;
+ text_rva = mem_offset;
+ emit_pecoff_section(".text", text_size, 0,
+ &file_offset, &mem_offset, SCN_RX |
+ IMAGE_SCN_CNT_CODE);
+
+ /* Check that kernel sections mapping is contiguous */
+ if (text_rva_diff != mem_offset - file_offset)
+ die("Kernel sections mapping is wrong: %#x != %#x",
+ mem_offset - file_offset, text_rva_diff);
+
+ emit_pecoff_section(".data", file_size - text_size, bss_size,
+ &file_offset, &mem_offset, SCN_RW |
+ IMAGE_SCN_CNT_INITIALIZED_DATA);
+
+ reloc_offset = file_offset;
+ reloc_rva = mem_offset;
+ emit_pecoff_section(".reloc", reloc_size, 0,
+ &file_offset, &mem_offset, SCN_RW |
+ IMAGE_SCN_CNT_INITIALIZED_DATA |
+ IMAGE_SCN_MEM_DISCARDABLE);
+
+ compat_offset = file_offset;
+#ifdef CONFIG_EFI_MIXED
+ emit_pecoff_section(".comat", compat_size, 0,
+ &file_offset, &mem_offset, SCN_RW |
+ IMAGE_SCN_CNT_INITIALIZED_DATA |
+ IMAGE_SCN_MEM_DISCARDABLE);
+#endif
+
+ if (file_size + setup_size + reloc_size + compat_size != file_offset)
+ die("file_size(%#x) != filesz(%#x)",
+ file_size + setup_size + reloc_size + compat_size, file_offset);
+
+ /* Size of code. */
+ put_unaligned_le32(round_up(text_size, SECTION_ALIGNMENT), &opt_hdr->text_size);
+ /*
+ * Size of data.
+ * Exclude text size and first sector, which contains PE header.
+ */
+ put_unaligned_le32(mem_offset - round_up(text_size, SECTION_ALIGNMENT),
+ &opt_hdr->data_size);
+
+ /* Size of image. */
+ put_unaligned_le32(mem_offset, &opt_hdr->image_size);
/*
* Address of entry point for PE/COFF executable
*/
- put_unaligned_le32(text_start + efi_pe_entry, &hdr->entry_point);
+ put_unaligned_le32(text_rva + efi_pe_entry, &opt_hdr->entry_point);
- update_pecoff_section_header_fields(".text", text_start, text_sz + bss_sz,
- text_sz, text_start);
+ /*
+ * BaseOfCode for PE/COFF executable
+ */
+ put_unaligned_le32(text_rva, &opt_hdr->code_base);
+
+ /*
+ * Since we have generated .reloc section, we need to
+ * fill-in Reloc directory
+ */
+ base_reloc = &get_data_dirs(buf)->base_relocations;
+ put_unaligned_le32(reloc_rva, &base_reloc->virtual_address);
+ put_unaligned_le32(RELOC_SECTION_SIZE, &base_reloc->size);
- return text_start + file_sz;
+ return file_offset;
}
-static int reserve_pecoff_reloc_section(int c)
+static void generate_pecoff_section_data(uint8_t *output)
{
- /* Reserve 0x20 bytes for .reloc section */
- memset(buf+c, 0, PECOFF_RELOC_RESERVE);
- return PECOFF_RELOC_RESERVE;
+ /*
+ * Modify .reloc section contents with a two entries. The
+ * relocation is applied to offset 10 of the relocation section.
+ */
+ put_unaligned_le32(reloc_offset + RELOC_SECTION_SIZE, &output[reloc_offset]);
+ put_unaligned_le32(RELOC_SECTION_SIZE, &output[reloc_offset + 4]);
+
+#ifdef CONFIG_EFI_MIXED
+ /*
+ * Put the IA-32 machine type (0x14c) and the associated entry point
+ * address in the .compat section, so loaders can figure out which other
+ * execution modes this image supports.
+ */
+ output[compat_offset] = 0x1;
+ output[compat_offset + 1] = 0x8;
+ put_unaligned_le16(IMAGE_FILE_MACHINE_I386, &output[compat_offset + 2]);
+ put_unaligned_le32(efi32_pe_entry + text_rva, &output[compat_offset + 4]);
+#endif
}
static void efi_stub_update_defaults(void)
@@ -405,26 +481,10 @@ static void efi_stub_entry_update(void)
#else
-static inline void update_pecoff_setup_and_reloc(unsigned int size) {}
-static inline void update_pecoff_text(unsigned int text_start,
- unsigned int file_sz,
- unsigned int init_sz) {}
-static inline void efi_stub_update_defaults(void) {}
-static inline void efi_stub_entry_update(void) {}
+static void efi_stub_update_defaults(void) {}
-static inline int reserve_pecoff_reloc_section(int c)
-{
- return 0;
-}
#endif /* CONFIG_EFI_STUB */
-static int reserve_pecoff_compat_section(int c)
-{
- /* Reserve 0x20 bytes for .compat section */
- memset(buf+c, 0, PECOFF_COMPAT_RESERVE);
- return PECOFF_COMPAT_RESERVE;
-}
-
/*
* Parse zoffset.h and find the entry points. We could just #include zoffset.h
* but that would mean tools/build would have to be rebuilt every time. It's
@@ -454,6 +514,7 @@ static void parse_zoffset(char *fname)
PARSE_ZOFS(p, efi32_pe_entry);
PARSE_ZOFS(p, kernel_info);
PARSE_ZOFS(p, startup_64);
+ PARSE_ZOFS(p, _rodata);
PARSE_ZOFS(p, _ehead);
PARSE_ZOFS(p, _end);
@@ -487,10 +548,6 @@ static unsigned int read_setup(char *path)
fclose(file);
- /* Reserve space for PE sections */
- file_size += reserve_pecoff_compat_section(file_size);
- file_size += reserve_pecoff_reloc_section(file_size);
-
/* Pad unused space with zeros */
setup_size = round_up(file_size, SECTOR_SIZE);
@@ -539,7 +596,6 @@ int main(int argc, char **argv)
#ifdef CONFIG_EFI_STUB
/* PE specification require 512-byte minimum section file alignment */
kern_size = round_up(kern_file_size + 4, SECTOR_SIZE);
- update_pecoff_setup_and_reloc(setup_size);
#else
/* Number of 16-byte paragraphs, including space for a 4-byte CRC */
kern_size = round_up(kern_file_size + 4, PARAGRAPH_SIZE);
@@ -574,7 +630,7 @@ int main(int argc, char **argv)
put_unaligned_le32(init_size, &buf[0x260]);
}
- total_size = update_pecoff_sections(setup_size, kern_size, init_size);
+ total_size = update_pecoff_sections(setup_size, kern_size, init_size, _rodata);
efi_stub_entry_update();
#else
@@ -588,6 +644,10 @@ int main(int argc, char **argv)
memcpy(output + setup_size, kernel, kern_file_size);
memset(output + setup_size + kern_file_size, 0, kern_size - kern_file_size);
+#ifdef CONFIG_EFI_STUB
+ generate_pecoff_section_data(output);
+#endif
+
/* Calculate and write kernel checksum. */
crc = partial_crc32(output, total_size - 4, crc);
put_unaligned_le32(crc, &output[total_size - 4]);
diff --git a/drivers/firmware/efi/libstub/x86-stub.c b/drivers/firmware/efi/libstub/x86-stub.c
index 8f172b688b0c..4d9588d33479 100644
--- a/drivers/firmware/efi/libstub/x86-stub.c
+++ b/drivers/firmware/efi/libstub/x86-stub.c
@@ -389,8 +389,11 @@ efi_status_t __efiapi efi_pe_entry(efi_handle_t handle,
hdr = &boot_params->hdr;
- /* Copy the setup header from the second sector to boot_params */
- memcpy(&hdr->jump, image_base + 512,
+ /*
+ * Copy the setup header from the second sector
+ * (mapped to image_base + 0x1000) to boot_params
+ */
+ memcpy(&hdr->jump, image_base + 0x1000,
sizeof(struct setup_header) - offsetof(struct setup_header, jump));
/*
--
2.37.4
EFI_MEMORY_ATTRIBUTE_PROTOCOL servers as a better alternative to
DXE services for setting memory attributes in EFI Boot Services
environment. This protocol is better since it is a part of UEFI
specification itself and not UEFI PI specification like DXE
services.
Add EFI_MEMORY_ATTRIBUTE_PROTOCOL definitions.
Support mixed mode properly for its calls.
Signed-off-by: Evgeniy Baskov <[email protected]>
---
arch/x86/include/asm/efi.h | 7 +++++++
drivers/firmware/efi/libstub/efistub.h | 22 ++++++++++++++++++++++
include/linux/efi.h | 1 +
3 files changed, 30 insertions(+)
diff --git a/arch/x86/include/asm/efi.h b/arch/x86/include/asm/efi.h
index 233ae6986d6f..522ff2e443b3 100644
--- a/arch/x86/include/asm/efi.h
+++ b/arch/x86/include/asm/efi.h
@@ -325,6 +325,13 @@ static inline u32 efi64_convert_status(efi_status_t status)
#define __efi64_argmap_set_memory_space_attributes(phys, size, flags) \
(__efi64_split(phys), __efi64_split(size), __efi64_split(flags))
+/* Memory Attribute Protocol */
+#define __efi64_argmap_set_memory_attributes(protocol, phys, size, flags) \
+ ((protocol), __efi64_split(phys), __efi64_split(size), __efi64_split(flags))
+
+#define __efi64_argmap_clear_memory_attributes(protocol, phys, size, flags) \
+ ((protocol), __efi64_split(phys), __efi64_split(size), __efi64_split(flags))
+
/*
* The macros below handle the plumbing for the argument mapping. To add a
* mapping for a specific EFI method, simply define a macro
diff --git a/drivers/firmware/efi/libstub/efistub.h b/drivers/firmware/efi/libstub/efistub.h
index 63f5157341fe..b9ea9e2c3010 100644
--- a/drivers/firmware/efi/libstub/efistub.h
+++ b/drivers/firmware/efi/libstub/efistub.h
@@ -39,6 +39,9 @@ extern const efi_system_table_t *efi_system_table;
typedef union efi_dxe_services_table efi_dxe_services_table_t;
extern const efi_dxe_services_table_t *efi_dxe_table;
+typedef union efi_memory_attribute_protocol efi_memory_attribute_protocol_t;
+extern efi_memory_attribute_protocol_t *efi_mem_attrib_proto;
+
efi_status_t __efiapi efi_pe_entry(efi_handle_t handle,
efi_system_table_t *sys_table_arg);
@@ -415,6 +418,25 @@ union efi_dxe_services_table {
} mixed_mode;
};
+union efi_memory_attribute_protocol {
+ struct {
+ void *get_memory_attributes;
+ efi_status_t (__efiapi *set_memory_attributes)(efi_memory_attribute_protocol_t *,
+ efi_physical_addr_t,
+ u64,
+ u64);
+ efi_status_t (__efiapi *clear_memory_attributes)(efi_memory_attribute_protocol_t *,
+ efi_physical_addr_t,
+ u64,
+ u64);
+ };
+ struct {
+ u32 get_memory_attributes;
+ u32 set_memory_attributes;
+ u32 clear_memory_attributes;
+ } mixed_mode;
+};
+
typedef union efi_uga_draw_protocol efi_uga_draw_protocol_t;
union efi_uga_draw_protocol {
diff --git a/include/linux/efi.h b/include/linux/efi.h
index 80f3c1c7827d..2d13c6eafc19 100644
--- a/include/linux/efi.h
+++ b/include/linux/efi.h
@@ -389,6 +389,7 @@ void efi_native_runtime_setup(void);
#define EFI_LOAD_FILE2_PROTOCOL_GUID EFI_GUID(0x4006c0c1, 0xfcb3, 0x403e, 0x99, 0x6d, 0x4a, 0x6c, 0x87, 0x24, 0xe0, 0x6d)
#define EFI_RT_PROPERTIES_TABLE_GUID EFI_GUID(0xeb66918a, 0x7eef, 0x402a, 0x84, 0x2e, 0x93, 0x1d, 0x21, 0xc3, 0x8a, 0xe9)
#define EFI_DXE_SERVICES_TABLE_GUID EFI_GUID(0x05ad34ba, 0x6f02, 0x4214, 0x95, 0x2e, 0x4d, 0xa0, 0x39, 0x8e, 0x2b, 0xb9)
+#define EFI_MEMORY_ATTRIBUTE_PROTOCOL_GUID EFI_GUID(0xf4560cf6, 0x40ec, 0x4b4a, 0xa1, 0x92, 0xbf, 0x1d, 0x57, 0xd0, 0xb1, 0x89)
#define EFI_IMAGE_SECURITY_DATABASE_GUID EFI_GUID(0xd719b2cb, 0x3d3a, 0x4596, 0xa3, 0xbc, 0xda, 0xd0, 0x0e, 0x67, 0x65, 0x6f)
#define EFI_SHIM_LOCK_GUID EFI_GUID(0x605dab50, 0xe046, 0x4300, 0xab, 0xb6, 0x3d, 0xd8, 0x10, 0xdd, 0x8b, 0x23)
--
2.37.4
Use newer C standard. Since kernel requires C99 compiler now,
we can make use of the new features to make the core more readable.
Use mmap() for reading files also to make things simpler.
Replace most magic numbers with defines.
Should have no functional changes. This is done in preparation for the
next changes that makes generated PE header more spec compliant.
Signed-off-by: Evgeniy Baskov <[email protected]>
---
arch/x86/boot/tools/build.c | 387 +++++++++++++++++++++++-------------
1 file changed, 245 insertions(+), 142 deletions(-)
diff --git a/arch/x86/boot/tools/build.c b/arch/x86/boot/tools/build.c
index a3725ad46c5a..9202645fec72 100644
--- a/arch/x86/boot/tools/build.c
+++ b/arch/x86/boot/tools/build.c
@@ -25,20 +25,21 @@
* Substantially overhauled by H. Peter Anvin, April 2007
*/
+#include <fcntl.h>
+#include <stdarg.h>
+#include <stdint.h>
#include <stdio.h>
-#include <string.h>
#include <stdlib.h>
-#include <stdarg.h>
-#include <sys/types.h>
+#include <string.h>
+#include <sys/mman.h>
#include <sys/stat.h>
+#include <sys/types.h>
#include <unistd.h>
-#include <fcntl.h>
-#include <sys/mman.h>
+
#include <tools/le_byteshift.h>
+#include <linux/pe.h>
-typedef unsigned char u8;
-typedef unsigned short u16;
-typedef unsigned int u32;
+#define round_up(x, n) (((x) + (n) - 1) & ~((n) - 1))
#define DEFAULT_MAJOR_ROOT 0
#define DEFAULT_MINOR_ROOT 0
@@ -48,8 +49,13 @@ typedef unsigned int u32;
#define SETUP_SECT_MIN 5
#define SETUP_SECT_MAX 64
+#define PARAGRAPH_SIZE 16
+#define SECTOR_SIZE 512
+#define FILE_ALIGNMENT 512
+#define SECTION_ALIGNMENT 4096
+
/* This must be large enough to hold the entire setup */
-u8 buf[SETUP_SECT_MAX*512];
+uint8_t buf[SETUP_SECT_MAX*SECTOR_SIZE];
#define PECOFF_RELOC_RESERVE 0x20
@@ -59,6 +65,52 @@ u8 buf[SETUP_SECT_MAX*512];
#define PECOFF_COMPAT_RESERVE 0x0
#endif
+#define RELOC_SECTION_SIZE 10
+
+/* PE header has different format depending on the architecture */
+#ifdef CONFIG_X86_64
+typedef struct pe32plus_opt_hdr pe_opt_hdr;
+#else
+typedef struct pe32_opt_hdr pe_opt_hdr;
+#endif
+
+static inline struct pe_hdr *get_pe_header(uint8_t *buf)
+{
+ uint32_t pe_offset = get_unaligned_le32(buf+MZ_HEADER_PEADDR_OFFSET);
+ return (struct pe_hdr *)(buf + pe_offset);
+}
+
+static inline pe_opt_hdr *get_pe_opt_header(uint8_t *buf)
+{
+ return (pe_opt_hdr *)(get_pe_header(buf) + 1);
+}
+
+static inline struct section_header *get_sections(uint8_t *buf)
+{
+ pe_opt_hdr *hdr = get_pe_opt_header(buf);
+ uint32_t n_data_dirs = get_unaligned_le32(&hdr->data_dirs);
+ uint8_t *sections = (uint8_t *)(hdr + 1) + n_data_dirs*sizeof(struct data_dirent);
+ return (struct section_header *)sections;
+}
+
+static inline struct data_directory *get_data_dirs(uint8_t *buf)
+{
+ pe_opt_hdr *hdr = get_pe_opt_header(buf);
+ return (struct data_directory *)(hdr + 1);
+}
+
+#ifdef CONFIG_EFI_DXE_MEM_ATTRIBUTES
+#define SCN_RW (IMAGE_SCN_MEM_READ | IMAGE_SCN_MEM_WRITE | IMAGE_SCN_ALIGN_4096BYTES)
+#define SCN_RX (IMAGE_SCN_MEM_READ | IMAGE_SCN_MEM_EXECUTE | IMAGE_SCN_ALIGN_4096BYTES)
+#define SCN_RO (IMAGE_SCN_MEM_READ | IMAGE_SCN_ALIGN_4096BYTES)
+#else
+/* With memory protection disabled all sections are RWX */
+#define SCN_RW (IMAGE_SCN_MEM_READ | IMAGE_SCN_MEM_WRITE | \
+ IMAGE_SCN_MEM_EXECUTE | IMAGE_SCN_ALIGN_4096BYTES)
+#define SCN_RX SCN_RW
+#define SCN_RO SCN_RW
+#endif
+
static unsigned long efi32_stub_entry;
static unsigned long efi64_stub_entry;
static unsigned long efi_pe_entry;
@@ -70,7 +122,7 @@ static unsigned long _end;
/*----------------------------------------------------------------------*/
-static const u32 crctab32[] = {
+static const uint32_t crctab32[] = {
0x00000000, 0x77073096, 0xee0e612c, 0x990951ba, 0x076dc419,
0x706af48f, 0xe963a535, 0x9e6495a3, 0x0edb8832, 0x79dcb8a4,
0xe0d5e91e, 0x97d2d988, 0x09b64c2b, 0x7eb17cbd, 0xe7b82d07,
@@ -125,12 +177,12 @@ static const u32 crctab32[] = {
0x2d02ef8d
};
-static u32 partial_crc32_one(u8 c, u32 crc)
+static uint32_t partial_crc32_one(uint8_t c, uint32_t crc)
{
return crctab32[(crc ^ c) & 0xff] ^ (crc >> 8);
}
-static u32 partial_crc32(const u8 *s, int len, u32 crc)
+static uint32_t partial_crc32(const uint8_t *s, int len, uint32_t crc)
{
while (len--)
crc = partial_crc32_one(*s++, crc);
@@ -152,57 +204,106 @@ static void usage(void)
die("Usage: build setup system zoffset.h image");
}
+static void *map_file(const char *path, size_t *psize)
+{
+ struct stat statbuf;
+ size_t size;
+ void *addr;
+ int fd;
+
+ fd = open(path, O_RDONLY);
+ if (fd < 0)
+ die("Unable to open `%s': %m", path);
+ if (fstat(fd, &statbuf))
+ die("Unable to stat `%s': %m", path);
+
+ size = statbuf.st_size;
+ /*
+ * Map one byte more, to allow adding null-terminator
+ * for text files.
+ */
+ addr = mmap(NULL, size + 1, PROT_READ | PROT_WRITE, MAP_PRIVATE, fd, 0);
+ if (addr == MAP_FAILED)
+ die("Unable to mmap '%s': %m", path);
+
+ close(fd);
+
+ *psize = size;
+ return addr;
+}
+
+static void unmap_file(void *addr, size_t size)
+{
+ munmap(addr, size + 1);
+}
+
+static void *map_output_file(const char *path, size_t size)
+{
+ void *addr;
+ int fd;
+
+ fd = open(path, O_RDWR | O_CREAT, 0660);
+ if (fd < 0)
+ die("Unable to create `%s': %m", path);
+
+ if (ftruncate(fd, size))
+ die("Unable to resize `%s': %m", path);
+
+ addr = mmap(NULL, size, PROT_READ | PROT_WRITE, MAP_SHARED, fd, 0);
+ if (addr == MAP_FAILED)
+ die("Unable to mmap '%s': %m", path);
+
+ return addr;
+}
+
#ifdef CONFIG_EFI_STUB
-static void update_pecoff_section_header_fields(char *section_name, u32 vma, u32 size, u32 datasz, u32 offset)
+static void update_pecoff_section_header_fields(char *section_name, uint32_t vma,
+ uint32_t size, uint32_t datasz,
+ uint32_t offset)
{
unsigned int pe_header;
unsigned short num_sections;
- u8 *section;
+ struct section_header *section;
- pe_header = get_unaligned_le32(&buf[0x3c]);
- num_sections = get_unaligned_le16(&buf[pe_header + 6]);
-
-#ifdef CONFIG_X86_32
- section = &buf[pe_header + 0xa8];
-#else
- section = &buf[pe_header + 0xb8];
-#endif
+ struct pe_hdr *hdr = get_pe_header(buf);
+ num_sections = get_unaligned_le16(&hdr->sections);
+ section = get_sections(buf);
while (num_sections > 0) {
- if (strncmp((char*)section, section_name, 8) == 0) {
+ if (strncmp(section->name, section_name, 8) == 0) {
/* section header size field */
- put_unaligned_le32(size, section + 0x8);
+ put_unaligned_le32(size, §ion->virtual_size);
/* section header vma field */
- put_unaligned_le32(vma, section + 0xc);
+ put_unaligned_le32(vma, §ion->virtual_address);
/* section header 'size of initialised data' field */
- put_unaligned_le32(datasz, section + 0x10);
+ put_unaligned_le32(datasz, §ion->raw_data_size);
/* section header 'file offset' field */
- put_unaligned_le32(offset, section + 0x14);
+ put_unaligned_le32(offset, §ion->data_addr);
break;
}
- section += 0x28;
+ section++;
num_sections--;
}
}
-static void update_pecoff_section_header(char *section_name, u32 offset, u32 size)
+static void update_pecoff_section_header(char *section_name, uint32_t offset, uint32_t size)
{
update_pecoff_section_header_fields(section_name, offset, size, size, offset);
}
static void update_pecoff_setup_and_reloc(unsigned int size)
{
- u32 setup_offset = 0x200;
- u32 reloc_offset = size - PECOFF_RELOC_RESERVE - PECOFF_COMPAT_RESERVE;
+ uint32_t setup_offset = SECTOR_SIZE;
+ uint32_t reloc_offset = size - PECOFF_RELOC_RESERVE - PECOFF_COMPAT_RESERVE;
#ifdef CONFIG_EFI_MIXED
- u32 compat_offset = reloc_offset + PECOFF_RELOC_RESERVE;
+ uint32_t compat_offset = reloc_offset + PECOFF_RELOC_RESERVE;
#endif
- u32 setup_size = reloc_offset - setup_offset;
+ uint32_t setup_size = reloc_offset - setup_offset;
update_pecoff_section_header(".setup", setup_offset, setup_size);
update_pecoff_section_header(".reloc", reloc_offset, PECOFF_RELOC_RESERVE);
@@ -211,8 +312,8 @@ static void update_pecoff_setup_and_reloc(unsigned int size)
* Modify .reloc section contents with a single entry. The
* relocation is applied to offset 10 of the relocation section.
*/
- put_unaligned_le32(reloc_offset + 10, &buf[reloc_offset]);
- put_unaligned_le32(10, &buf[reloc_offset + 4]);
+ put_unaligned_le32(reloc_offset + RELOC_SECTION_SIZE, &buf[reloc_offset]);
+ put_unaligned_le32(RELOC_SECTION_SIZE, &buf[reloc_offset + 4]);
#ifdef CONFIG_EFI_MIXED
update_pecoff_section_header(".compat", compat_offset, PECOFF_COMPAT_RESERVE);
@@ -224,19 +325,17 @@ static void update_pecoff_setup_and_reloc(unsigned int size)
*/
buf[compat_offset] = 0x1;
buf[compat_offset + 1] = 0x8;
- put_unaligned_le16(0x14c, &buf[compat_offset + 2]);
+ put_unaligned_le16(IMAGE_FILE_MACHINE_I386, &buf[compat_offset + 2]);
put_unaligned_le32(efi32_pe_entry + size, &buf[compat_offset + 4]);
#endif
}
-static void update_pecoff_text(unsigned int text_start, unsigned int file_sz,
+static unsigned int update_pecoff_sections(unsigned int text_start, unsigned int text_sz,
unsigned int init_sz)
{
- unsigned int pe_header;
- unsigned int text_sz = file_sz - text_start;
+ unsigned int file_sz = text_start + text_sz;
unsigned int bss_sz = init_sz - file_sz;
-
- pe_header = get_unaligned_le32(&buf[0x3c]);
+ pe_opt_hdr *hdr = get_pe_opt_header(buf);
/*
* The PE/COFF loader may load the image at an address which is
@@ -254,18 +353,20 @@ static void update_pecoff_text(unsigned int text_start, unsigned int file_sz,
* Size of code: Subtract the size of the first sector (512 bytes)
* which includes the header.
*/
- put_unaligned_le32(file_sz - 512 + bss_sz, &buf[pe_header + 0x1c]);
+ put_unaligned_le32(file_sz - SECTOR_SIZE + bss_sz, &hdr->text_size);
/* Size of image */
- put_unaligned_le32(init_sz, &buf[pe_header + 0x50]);
+ put_unaligned_le32(init_sz, &hdr->image_size);
/*
* Address of entry point for PE/COFF executable
*/
- put_unaligned_le32(text_start + efi_pe_entry, &buf[pe_header + 0x28]);
+ put_unaligned_le32(text_start + efi_pe_entry, &hdr->entry_point);
update_pecoff_section_header_fields(".text", text_start, text_sz + bss_sz,
text_sz, text_start);
+
+ return text_start + file_sz;
}
static int reserve_pecoff_reloc_section(int c)
@@ -275,7 +376,7 @@ static int reserve_pecoff_reloc_section(int c)
return PECOFF_RELOC_RESERVE;
}
-static void efi_stub_defaults(void)
+static void efi_stub_update_defaults(void)
{
/* Defaults for old kernel */
#ifdef CONFIG_X86_32
@@ -297,7 +398,7 @@ static void efi_stub_entry_update(void)
#ifdef CONFIG_EFI_MIXED
if (efi32_stub_entry != addr)
- die("32-bit and 64-bit EFI entry points do not match\n");
+ die("32-bit and 64-bit EFI entry points do not match");
#endif
put_unaligned_le32(addr, &buf[0x264]);
}
@@ -308,7 +409,7 @@ static inline void update_pecoff_setup_and_reloc(unsigned int size) {}
static inline void update_pecoff_text(unsigned int text_start,
unsigned int file_sz,
unsigned int init_sz) {}
-static inline void efi_stub_defaults(void) {}
+static inline void efi_stub_update_defaults(void) {}
static inline void efi_stub_entry_update(void) {}
static inline int reserve_pecoff_reloc_section(int c)
@@ -336,20 +437,15 @@ static int reserve_pecoff_compat_section(int c)
static void parse_zoffset(char *fname)
{
- FILE *file;
- char *p;
- int c;
+ size_t size;
+ char *data, *p;
- file = fopen(fname, "r");
- if (!file)
- die("Unable to open `%s': %m", fname);
- c = fread(buf, 1, sizeof(buf) - 1, file);
- if (ferror(file))
- die("read-error on `zoffset.h'");
- fclose(file);
- buf[c] = 0;
+ data = map_file(fname, &size);
- p = (char *)buf;
+ /* We can do that, since we mapped one byte more */
+ data[size] = 0;
+
+ p = (char *)data;
while (p && *p) {
PARSE_ZOFS(p, efi32_stub_entry);
@@ -365,82 +461,99 @@ static void parse_zoffset(char *fname)
while (p && (*p == '\r' || *p == '\n'))
p++;
}
+
+ unmap_file(data, size);
}
-int main(int argc, char ** argv)
+static unsigned int read_setup(char *path)
{
- unsigned int i, sz, setup_sectors, init_sz;
- int c;
- u32 sys_size;
- struct stat sb;
- FILE *file, *dest;
- int fd;
- void *kernel;
- u32 crc = 0xffffffffUL;
-
- efi_stub_defaults();
-
- if (argc != 5)
- usage();
- parse_zoffset(argv[3]);
-
- dest = fopen(argv[4], "w");
- if (!dest)
- die("Unable to write `%s': %m", argv[4]);
+ FILE *file;
+ unsigned int setup_size, file_size;
/* Copy the setup code */
- file = fopen(argv[1], "r");
+ file = fopen(path, "r");
if (!file)
- die("Unable to open `%s': %m", argv[1]);
- c = fread(buf, 1, sizeof(buf), file);
+ die("Unable to open `%s': %m", path);
+
+ file_size = fread(buf, 1, sizeof(buf), file);
if (ferror(file))
die("read-error on `setup'");
- if (c < 1024)
+
+ if (file_size < 2 * SECTOR_SIZE)
die("The setup must be at least 1024 bytes");
- if (get_unaligned_le16(&buf[510]) != 0xAA55)
+
+ if (get_unaligned_le16(&buf[SECTOR_SIZE - 2]) != 0xAA55)
die("Boot block hasn't got boot flag (0xAA55)");
+
fclose(file);
- c += reserve_pecoff_compat_section(c);
- c += reserve_pecoff_reloc_section(c);
+ /* Reserve space for PE sections */
+ file_size += reserve_pecoff_compat_section(file_size);
+ file_size += reserve_pecoff_reloc_section(file_size);
/* Pad unused space with zeros */
- setup_sectors = (c + 511) / 512;
- if (setup_sectors < SETUP_SECT_MIN)
- setup_sectors = SETUP_SECT_MIN;
- i = setup_sectors*512;
- memset(buf+c, 0, i-c);
- update_pecoff_setup_and_reloc(i);
+ setup_size = round_up(file_size, SECTOR_SIZE);
+
+ if (setup_size < SETUP_SECT_MIN * SECTOR_SIZE)
+ setup_size = SETUP_SECT_MIN * SECTOR_SIZE;
+
+ /*
+ * Global buffer is already initialised
+ * to 0, but just in case, zero out padding.
+ */
+
+ memset(buf + file_size, 0, setup_size - file_size);
+
+ return setup_size;
+}
+
+int main(int argc, char **argv)
+{
+ size_t kern_file_size;
+ unsigned int setup_size;
+ unsigned int setup_sectors;
+ unsigned int init_size;
+ unsigned int total_size;
+ unsigned int kern_size;
+ void *kernel;
+ uint32_t crc = 0xffffffffUL;
+ uint8_t *output;
+
+ if (argc != 5)
+ usage();
+
+ efi_stub_update_defaults();
+ parse_zoffset(argv[3]);
+
+ setup_size = read_setup(argv[1]);
+
+ setup_sectors = setup_size/SECTOR_SIZE;
/* Set the default root device */
put_unaligned_le16(DEFAULT_ROOT_DEV, &buf[508]);
- /* Open and stat the kernel file */
- fd = open(argv[2], O_RDONLY);
- if (fd < 0)
- die("Unable to open `%s': %m", argv[2]);
- if (fstat(fd, &sb))
- die("Unable to stat `%s': %m", argv[2]);
- sz = sb.st_size;
- kernel = mmap(NULL, sz, PROT_READ, MAP_SHARED, fd, 0);
- if (kernel == MAP_FAILED)
- die("Unable to mmap '%s': %m", argv[2]);
- /* Number of 16-byte paragraphs, including space for a 4-byte CRC */
- sys_size = (sz + 15 + 4) / 16;
+ /* Map kernel file to memory */
+ kernel = map_file(argv[2], &kern_file_size);
+
#ifdef CONFIG_EFI_STUB
- /*
- * COFF requires minimum 32-byte alignment of sections, and
- * adding a signature is problematic without that alignment.
- */
- sys_size = (sys_size + 1) & ~1;
+ /* PE specification require 512-byte minimum section file alignment */
+ kern_size = round_up(kern_file_size + 4, SECTOR_SIZE);
+ update_pecoff_setup_and_reloc(setup_size);
+#else
+ /* Number of 16-byte paragraphs, including space for a 4-byte CRC */
+ kern_size = round_up(kern_file_size + 4, PARAGRAPH_SIZE);
#endif
/* Patch the setup code with the appropriate size parameters */
- buf[0x1f1] = setup_sectors-1;
- put_unaligned_le32(sys_size, &buf[0x1f4]);
+ buf[0x1f1] = setup_sectors - 1;
+ put_unaligned_le32(kern_size/PARAGRAPH_SIZE, &buf[0x1f4]);
+
+ /* Update kernel_info offset. */
+ put_unaligned_le32(kernel_info, &buf[0x268]);
+
+ init_size = get_unaligned_le32(&buf[0x260]);
- init_sz = get_unaligned_le32(&buf[0x260]);
#ifdef CONFIG_EFI_STUB
/*
* The decompression buffer will start at ImageBase. When relocating
@@ -456,45 +569,35 @@ int main(int argc, char ** argv)
* For future-proofing, increase init_sz if necessary.
*/
- if (init_sz - _end < i + _ehead) {
- init_sz = (i + _ehead + _end + 4095) & ~4095;
- put_unaligned_le32(init_sz, &buf[0x260]);
+ if (init_size - _end < setup_size + _ehead) {
+ init_size = round_up(setup_size + _ehead + _end, SECTION_ALIGNMENT);
+ put_unaligned_le32(init_size, &buf[0x260]);
}
-#endif
- update_pecoff_text(setup_sectors * 512, i + (sys_size * 16), init_sz);
- efi_stub_entry_update();
-
- /* Update kernel_info offset. */
- put_unaligned_le32(kernel_info, &buf[0x268]);
+ total_size = update_pecoff_sections(setup_size, kern_size, init_size);
- crc = partial_crc32(buf, i, crc);
- if (fwrite(buf, 1, i, dest) != i)
- die("Writing setup failed");
+ efi_stub_entry_update();
+#else
+ (void)init_size;
+ total_size = setup_size + kern_size;
+#endif
- /* Copy the kernel code */
- crc = partial_crc32(kernel, sz, crc);
- if (fwrite(kernel, 1, sz, dest) != sz)
- die("Writing kernel failed");
+ output = map_output_file(argv[4], total_size);
- /* Add padding leaving 4 bytes for the checksum */
- while (sz++ < (sys_size*16) - 4) {
- crc = partial_crc32_one('\0', crc);
- if (fwrite("\0", 1, 1, dest) != 1)
- die("Writing padding failed");
- }
+ memcpy(output, buf, setup_size);
+ memcpy(output + setup_size, kernel, kern_file_size);
+ memset(output + setup_size + kern_file_size, 0, kern_size - kern_file_size);
- /* Write the CRC */
- put_unaligned_le32(crc, buf);
- if (fwrite(buf, 1, 4, dest) != 4)
- die("Writing CRC failed");
+ /* Calculate and write kernel checksum. */
+ crc = partial_crc32(output, total_size - 4, crc);
+ put_unaligned_le32(crc, &output[total_size - 4]);
- /* Catch any delayed write failures */
- if (fclose(dest))
- die("Writing image failed");
+ /* Catch any delayed write failures. */
+ if (munmap(output, total_size) < 0)
+ die("Writing kernel failed");
- close(fd);
+ unmap_file(kernel, kern_file_size);
- /* Everything is OK */
+ /* Everything is OK. */
return 0;
}
--
2.37.4
Convert kernel_add_identity_map() into a function pointer to be able
to provide alternative implementations of this function. Required
to enable calling the code using this function from EFI environment.
Signed-off-by: Evgeniy Baskov <[email protected]>
---
arch/x86/boot/compressed/ident_map_64.c | 7 ++++---
arch/x86/boot/compressed/misc.c | 24 ++++++++++++++++++++++++
arch/x86/boot/compressed/misc.h | 15 +++------------
3 files changed, 31 insertions(+), 15 deletions(-)
diff --git a/arch/x86/boot/compressed/ident_map_64.c b/arch/x86/boot/compressed/ident_map_64.c
index ba5108c58a4e..1aee524d3c2b 100644
--- a/arch/x86/boot/compressed/ident_map_64.c
+++ b/arch/x86/boot/compressed/ident_map_64.c
@@ -92,9 +92,9 @@ bool has_nx; /* set in head_64.S */
/*
* Adds the specified range to the identity mappings.
*/
-unsigned long kernel_add_identity_map(unsigned long start,
- unsigned long end,
- unsigned int flags)
+unsigned long kernel_add_identity_map_(unsigned long start,
+ unsigned long end,
+ unsigned int flags)
{
int ret;
@@ -142,6 +142,7 @@ void initialize_identity_maps(void *rmode)
struct setup_data *sd;
boot_params = rmode;
+ kernel_add_identity_map = kernel_add_identity_map_;
/* Exclude the encryption mask from __PHYSICAL_MASK */
physical_mask &= ~sme_me_mask;
diff --git a/arch/x86/boot/compressed/misc.c b/arch/x86/boot/compressed/misc.c
index aa4a22bc9cf9..c9c235d65d16 100644
--- a/arch/x86/boot/compressed/misc.c
+++ b/arch/x86/boot/compressed/misc.c
@@ -275,6 +275,22 @@ static void parse_elf(void *output, unsigned long output_len,
free(phdrs);
}
+/*
+ * This points to actual implementation of mapping function
+ * for current environment: either EFI API wrapper,
+ * own implementation or dummy implementation below.
+ */
+unsigned long (*kernel_add_identity_map)(unsigned long start,
+ unsigned long end,
+ unsigned int flags);
+
+static inline unsigned long kernel_add_identity_map_dummy(unsigned long start,
+ unsigned long end,
+ unsigned int flags)
+{
+ return start;
+}
+
/*
* The compressed kernel image (ZO), has been moved so that its position
* is against the end of the buffer used to hold the uncompressed kernel
@@ -312,6 +328,14 @@ asmlinkage __visible void *extract_kernel(void *rmode, memptr heap,
init_default_io_ops();
+ /*
+ * On 64-bit this pointer is set during page table uninitialization,
+ * but on 32-bit it remains uninitialized, since paging is disabled.
+ */
+ if (IS_ENABLED(CONFIG_X86_32))
+ kernel_add_identity_map = kernel_add_identity_map_dummy;
+
+
/*
* Detect TDX guest environment.
*
diff --git a/arch/x86/boot/compressed/misc.h b/arch/x86/boot/compressed/misc.h
index 38d31bec062d..0076b2845b4b 100644
--- a/arch/x86/boot/compressed/misc.h
+++ b/arch/x86/boot/compressed/misc.h
@@ -180,18 +180,9 @@ static inline int count_immovable_mem_regions(void) { return 0; }
#ifdef CONFIG_X86_5LEVEL
extern unsigned int __pgtable_l5_enabled, pgdir_shift, ptrs_per_p4d;
#endif
-#ifdef CONFIG_X86_64
-extern unsigned long kernel_add_identity_map(unsigned long start,
- unsigned long end,
- unsigned int flags);
-#else
-static inline unsigned long kernel_add_identity_map(unsigned long start,
- unsigned long end,
- unsigned int flags)
-{
- return start;
-}
-#endif
+extern unsigned long (*kernel_add_identity_map)(unsigned long start,
+ unsigned long end,
+ unsigned int flags);
/* Used by PAGE_KERN* macros: */
extern pteval_t __default_kernel_pte_mask;
--
2.37.4
To be able to extract kernel from EFI, console output functions
need to be replaceable by alternative implementations.
Make all of those functions pointers.
Move serial console code to separate file.
Signed-off-by: Evgeniy Baskov <[email protected]>
---
arch/x86/boot/compressed/Makefile | 2 +-
arch/x86/boot/compressed/misc.c | 109 +------------------------
arch/x86/boot/compressed/misc.h | 9 ++-
arch/x86/boot/compressed/putstr.c | 130 ++++++++++++++++++++++++++++++
4 files changed, 139 insertions(+), 111 deletions(-)
create mode 100644 arch/x86/boot/compressed/putstr.c
diff --git a/arch/x86/boot/compressed/Makefile b/arch/x86/boot/compressed/Makefile
index 64de6c2b1740..f79273f46cc7 100644
--- a/arch/x86/boot/compressed/Makefile
+++ b/arch/x86/boot/compressed/Makefile
@@ -93,7 +93,7 @@ $(obj)/misc.o: $(obj)/../voffset.h
vmlinux-objs-y := $(obj)/vmlinux.lds $(obj)/kernel_info.o $(obj)/head_$(BITS).o \
$(obj)/misc.o $(obj)/string.o $(obj)/cmdline.o $(obj)/error.o \
- $(obj)/piggy.o $(obj)/cpuflags.o
+ $(obj)/piggy.o $(obj)/cpuflags.o $(obj)/putstr.o
vmlinux-objs-$(CONFIG_EARLY_PRINTK) += $(obj)/early_serial_console.o
vmlinux-objs-$(CONFIG_RANDOMIZE_BASE) += $(obj)/kaslr.o
diff --git a/arch/x86/boot/compressed/misc.c b/arch/x86/boot/compressed/misc.c
index 0c7ec290044d..aa4a22bc9cf9 100644
--- a/arch/x86/boot/compressed/misc.c
+++ b/arch/x86/boot/compressed/misc.c
@@ -53,13 +53,6 @@ struct port_io_ops pio_ops;
memptr free_mem_ptr;
memptr free_mem_end_ptr;
-static char *vidmem;
-static int vidport;
-
-/* These might be accessed before .bss is cleared, so use .data instead. */
-static int lines __section(".data");
-static int cols __section(".data");
-
#ifdef CONFIG_KERNEL_GZIP
#include "../../../../lib/decompress_inflate.c"
#endif
@@ -92,95 +85,6 @@ static int cols __section(".data");
* ../header.S.
*/
-static void scroll(void)
-{
- int i;
-
- memmove(vidmem, vidmem + cols * 2, (lines - 1) * cols * 2);
- for (i = (lines - 1) * cols * 2; i < lines * cols * 2; i += 2)
- vidmem[i] = ' ';
-}
-
-#define XMTRDY 0x20
-
-#define TXR 0 /* Transmit register (WRITE) */
-#define LSR 5 /* Line Status */
-static void serial_putchar(int ch)
-{
- unsigned timeout = 0xffff;
-
- while ((inb(early_serial_base + LSR) & XMTRDY) == 0 && --timeout)
- cpu_relax();
-
- outb(ch, early_serial_base + TXR);
-}
-
-void __putstr(const char *s)
-{
- int x, y, pos;
- char c;
-
- if (early_serial_base) {
- const char *str = s;
- while (*str) {
- if (*str == '\n')
- serial_putchar('\r');
- serial_putchar(*str++);
- }
- }
-
- if (lines == 0 || cols == 0)
- return;
-
- x = boot_params->screen_info.orig_x;
- y = boot_params->screen_info.orig_y;
-
- while ((c = *s++) != '\0') {
- if (c == '\n') {
- x = 0;
- if (++y >= lines) {
- scroll();
- y--;
- }
- } else {
- vidmem[(x + cols * y) * 2] = c;
- if (++x >= cols) {
- x = 0;
- if (++y >= lines) {
- scroll();
- y--;
- }
- }
- }
- }
-
- boot_params->screen_info.orig_x = x;
- boot_params->screen_info.orig_y = y;
-
- pos = (x + cols * y) * 2; /* Update cursor position */
- outb(14, vidport);
- outb(0xff & (pos >> 9), vidport+1);
- outb(15, vidport);
- outb(0xff & (pos >> 1), vidport+1);
-}
-
-void __puthex(unsigned long value)
-{
- char alpha[2] = "0";
- int bits;
-
- for (bits = sizeof(value) * 8 - 4; bits >= 0; bits -= 4) {
- unsigned long digit = (value >> bits) & 0xf;
-
- if (digit < 0xA)
- alpha[0] = '0' + digit;
- else
- alpha[0] = 'a' + (digit - 0xA);
-
- __putstr(alpha);
- }
-}
-
#ifdef CONFIG_X86_NEED_RELOCS
static void handle_relocations(void *output, unsigned long output_len,
unsigned long virt_addr)
@@ -406,17 +310,6 @@ asmlinkage __visible void *extract_kernel(void *rmode, memptr heap,
sanitize_boot_params(boot_params);
- if (boot_params->screen_info.orig_video_mode == 7) {
- vidmem = (char *) 0xb0000;
- vidport = 0x3b4;
- } else {
- vidmem = (char *) 0xb8000;
- vidport = 0x3d4;
- }
-
- lines = boot_params->screen_info.orig_video_lines;
- cols = boot_params->screen_info.orig_video_cols;
-
init_default_io_ops();
/*
@@ -427,7 +320,7 @@ asmlinkage __visible void *extract_kernel(void *rmode, memptr heap,
*/
early_tdx_detect();
- console_init();
+ init_bare_console();
/*
* Save RSDP address for later use. Have this after console_init()
diff --git a/arch/x86/boot/compressed/misc.h b/arch/x86/boot/compressed/misc.h
index 033db9b536e6..38d31bec062d 100644
--- a/arch/x86/boot/compressed/misc.h
+++ b/arch/x86/boot/compressed/misc.h
@@ -57,8 +57,8 @@ extern memptr free_mem_end_ptr;
void *malloc(int size);
void free(void *where);
extern struct boot_params *boot_params;
-void __putstr(const char *s);
-void __puthex(unsigned long value);
+extern void (*__putstr)(const char *s);
+extern void (*__puthex)(unsigned long value);
#define error_putstr(__x) __putstr(__x)
#define error_puthex(__x) __puthex(__x)
@@ -128,6 +128,11 @@ static inline void console_init(void)
{ }
#endif
+/* putstr.c */
+void init_bare_console(void);
+void init_console_func(void (*putstr_)(const char *),
+ void (*puthex_)(unsigned long));
+
#ifdef CONFIG_AMD_MEM_ENCRYPT
void sev_enable(struct boot_params *bp);
void sev_es_shutdown_ghcb(void);
diff --git a/arch/x86/boot/compressed/putstr.c b/arch/x86/boot/compressed/putstr.c
new file mode 100644
index 000000000000..44a4c3dacec5
--- /dev/null
+++ b/arch/x86/boot/compressed/putstr.c
@@ -0,0 +1,130 @@
+// SPDX-License-Identifier: GPL-2.0
+#include "misc.h"
+
+/* These might be accessed before .bss is cleared, so use .data instead. */
+static char *vidmem __section(".data");
+static int vidport __section(".data");
+static int lines __section(".data");
+static int cols __section(".data");
+
+void (*__putstr)(const char *s);
+void (*__puthex)(unsigned long value);
+
+static void putstr(const char *s);
+static void puthex(unsigned long value);
+
+void init_console_func(void (*putstr_)(const char *),
+ void (*puthex_)(unsigned long))
+{
+ __putstr = putstr_;
+ __puthex = puthex_;
+}
+
+void init_bare_console(void)
+{
+ init_console_func(putstr, puthex);
+
+ if (boot_params->screen_info.orig_video_mode == 7) {
+ vidmem = (char *) 0xb0000;
+ vidport = 0x3b4;
+ } else {
+ vidmem = (char *) 0xb8000;
+ vidport = 0x3d4;
+ }
+
+ lines = boot_params->screen_info.orig_video_lines;
+ cols = boot_params->screen_info.orig_video_cols;
+
+ console_init();
+}
+
+static void scroll(void)
+{
+ int i;
+
+ memmove(vidmem, vidmem + cols * 2, (lines - 1) * cols * 2);
+ for (i = (lines - 1) * cols * 2; i < lines * cols * 2; i += 2)
+ vidmem[i] = ' ';
+}
+
+#define XMTRDY 0x20
+
+#define TXR 0 /* Transmit register (WRITE) */
+#define LSR 5 /* Line Status */
+
+static void serial_putchar(int ch)
+{
+ unsigned int timeout = 0xffff;
+
+ while ((inb(early_serial_base + LSR) & XMTRDY) == 0 && --timeout)
+ cpu_relax();
+
+ outb(ch, early_serial_base + TXR);
+}
+
+static void putstr(const char *s)
+{
+ int x, y, pos;
+ char c;
+
+ if (early_serial_base) {
+ const char *str = s;
+
+ while (*str) {
+ if (*str == '\n')
+ serial_putchar('\r');
+ serial_putchar(*str++);
+ }
+ }
+
+ if (lines == 0 || cols == 0)
+ return;
+
+ x = boot_params->screen_info.orig_x;
+ y = boot_params->screen_info.orig_y;
+
+ while ((c = *s++) != '\0') {
+ if (c == '\n') {
+ x = 0;
+ if (++y >= lines) {
+ scroll();
+ y--;
+ }
+ } else {
+ vidmem[(x + cols * y) * 2] = c;
+ if (++x >= cols) {
+ x = 0;
+ if (++y >= lines) {
+ scroll();
+ y--;
+ }
+ }
+ }
+ }
+
+ boot_params->screen_info.orig_x = x;
+ boot_params->screen_info.orig_y = y;
+
+ pos = (x + cols * y) * 2; /* Update cursor position */
+ outb(14, vidport);
+ outb(0xff & (pos >> 9), vidport+1);
+ outb(15, vidport);
+ outb(0xff & (pos >> 1), vidport+1);
+}
+
+static void puthex(unsigned long value)
+{
+ char alpha[2] = "0";
+ int bits;
+
+ for (bits = sizeof(value) * 8 - 4; bits >= 0; bits -= 4) {
+ unsigned long digit = (value >> bits) & 0xf;
+
+ if (digit < 0xA)
+ alpha[0] = '0' + digit;
+ else
+ alpha[0] = 'a' + (digit - 0xA);
+
+ putstr(alpha);
+ }
+}
--
2.37.4
After every implicit mapping is removed, this code is no longer needed.
Remove memory mapping from page fault handler to ensure that there are
no hidden invalid memory accesses.
Signed-off-by: Evgeniy Baskov <[email protected]>
---
arch/x86/boot/compressed/ident_map_64.c | 26 ++++++++++---------------
1 file changed, 10 insertions(+), 16 deletions(-)
diff --git a/arch/x86/boot/compressed/ident_map_64.c b/arch/x86/boot/compressed/ident_map_64.c
index fec795a4ce23..ba5108c58a4e 100644
--- a/arch/x86/boot/compressed/ident_map_64.c
+++ b/arch/x86/boot/compressed/ident_map_64.c
@@ -386,27 +386,21 @@ void do_boot_page_fault(struct pt_regs *regs, unsigned long error_code)
{
unsigned long address = native_read_cr2();
unsigned long end;
- bool ghcb_fault;
+ char *msg;
- ghcb_fault = sev_es_check_ghcb_fault(address);
+ if (sev_es_check_ghcb_fault(address))
+ msg = "Page-fault on GHCB page:";
+ else
+ msg = "Unexpected page-fault:";
address &= PMD_MASK;
end = address + PMD_SIZE;
/*
- * Check for unexpected error codes. Unexpected are:
- * - Faults on present pages
- * - User faults
- * - Reserved bits set
- */
- if (error_code & (X86_PF_PROT | X86_PF_USER | X86_PF_RSVD))
- do_pf_error("Unexpected page-fault:", error_code, address, regs->ip);
- else if (ghcb_fault)
- do_pf_error("Page-fault on GHCB page:", error_code, address, regs->ip);
-
- /*
- * Error code is sane - now identity map the 2M region around
- * the faulting address.
+ * Since all memory allocations are made explicit
+ * now, every page fault at this stage is an
+ * error and the error handler is there only
+ * for debug purposes.
*/
- kernel_add_identity_map(address, end, MAP_WRITE);
+ do_pf_error(msg, error_code, address, regs->ip);
}
--
2.37.4
Doing it that way allows setting up stricter memory attributes,
simplifies boot code path and removes potential relocation
of kernel image.
Wire up required interfaces and minimally initialize zero page
fields needed for it to function correctly.
Signed-off-by: Evgeniy Baskov <[email protected]>
create mode 100644 arch/x86/include/asm/shared/extract.h
create mode 100644 drivers/firmware/efi/libstub/x86-extract-direct.c
---
arch/x86/boot/compressed/head_32.S | 41 +++-
arch/x86/boot/compressed/head_64.S | 45 +++-
drivers/firmware/efi/Kconfig | 2 +
drivers/firmware/efi/libstub/Makefile | 2 +-
.../firmware/efi/libstub/x86-extract-direct.c | 204 ++++++++++++++++++
drivers/firmware/efi/libstub/x86-stub.c | 115 +---------
drivers/firmware/efi/libstub/x86-stub.h | 11 +
7 files changed, 307 insertions(+), 113 deletions(-)
create mode 100644 drivers/firmware/efi/libstub/x86-extract-direct.c
create mode 100644 drivers/firmware/efi/libstub/x86-stub.h
diff --git a/arch/x86/boot/compressed/head_32.S b/arch/x86/boot/compressed/head_32.S
index b46a1c4109cf..9871cc8466fb 100644
--- a/arch/x86/boot/compressed/head_32.S
+++ b/arch/x86/boot/compressed/head_32.S
@@ -155,8 +155,45 @@ SYM_FUNC_START(efi32_stub_entry)
add $0x4, %esp
movl 8(%esp), %esi /* save boot_params pointer */
call efi_main
- /* efi_main returns the possibly relocated address of startup_32 */
- jmp *%eax
+ movl %eax, %ecx
+
+ /*
+ * efi_main returns the possibly
+ * relocated address of extracted kernel entry point.
+ */
+
+ cli
+
+/*
+ * Calculate the delta between where we were compiled to run
+ * at and where we were actually loaded at. This can only be done
+ * with a short local call on x86. Nothing else will tell us what
+ * address we are running at. The reserved chunk of the real-mode
+ * data at 0x1e4 (defined as a scratch field) are used as the stack
+ * for this calculation. Only 4 bytes are needed.
+ */
+ call 1f
+1: popl %edx
+ addl $_GLOBAL_OFFSET_TABLE_+(.-1b), %edx
+
+ /* Load new GDT */
+ leal gdt@GOTOFF(%edx), %eax
+ movl %eax, 2(%eax)
+ lgdt (%eax)
+
+ /* Load segment registers with our descriptors */
+ movl $__BOOT_DS, %eax
+ movl %eax, %ds
+ movl %eax, %es
+ movl %eax, %fs
+ movl %eax, %gs
+ movl %eax, %ss
+
+ /* Zero EFLAGS */
+ pushl $0
+ popfl
+
+ jmp *%ecx
SYM_FUNC_END(efi32_stub_entry)
SYM_FUNC_ALIAS(efi_stub_entry, efi32_stub_entry)
#endif
diff --git a/arch/x86/boot/compressed/head_64.S b/arch/x86/boot/compressed/head_64.S
index 6cfcdeb4531b..476c9b665181 100644
--- a/arch/x86/boot/compressed/head_64.S
+++ b/arch/x86/boot/compressed/head_64.S
@@ -556,9 +556,48 @@ SYM_FUNC_START(efi64_stub_entry)
and $~0xf, %rsp /* realign the stack */
movq %rdx, %rbx /* save boot_params pointer */
call efi_main
- movq %rbx,%rsi
- leaq rva(startup_64)(%rax), %rax
- jmp *%rax
+
+ cld
+ cli
+
+ movq %rbx, %rdi /* boot_params */
+ movq %rax, %rsi /* decompressed kernel address */
+
+ /* Make sure we have GDT with 32-bit code segment */
+ leaq gdt64(%rip), %rax
+ addq %rax, 2(%rax)
+ lgdt (%rax)
+
+ /* Setup data segments. */
+ xorl %eax, %eax
+ movl %eax, %ds
+ movl %eax, %es
+ movl %eax, %ss
+ movl %eax, %fs
+ movl %eax, %gs
+
+ pushq %rsi
+ pushq %rdi
+
+ call enable_nx_if_supported
+
+ call trampoline_pgtable_init
+ movq %rax, %rdx
+
+
+ /* Swap %rsi and %rsi */
+ popq %rsi
+ popq %rdi
+
+ /* Save the trampoline address in RCX */
+ movq trampoline_32bit(%rip), %rcx
+
+ /* Switch to compatibility mode (CS.L = 0 CS.D = 1) via far return */
+ pushq $__KERNEL32_CS
+ leaq TRAMPOLINE_32BIT_CODE_OFFSET(%rcx), %rax
+ pushq %rax
+ lretq
+
SYM_FUNC_END(efi64_stub_entry)
SYM_FUNC_ALIAS(efi_stub_entry, efi64_stub_entry)
#endif
diff --git a/drivers/firmware/efi/Kconfig b/drivers/firmware/efi/Kconfig
index 6787ed8dfacf..388b2a0b4781 100644
--- a/drivers/firmware/efi/Kconfig
+++ b/drivers/firmware/efi/Kconfig
@@ -91,6 +91,8 @@ config EFI_DXE_MEM_ATTRIBUTES
Use DXE services to check and alter memory protection
attributes during boot via EFISTUB to ensure that memory
ranges used by the kernel are writable and executable.
+ This option also enables stricter memory attributes
+ on compressed kernel PE image.
config EFI_PARAMS_FROM_FDT
bool
diff --git a/drivers/firmware/efi/libstub/Makefile b/drivers/firmware/efi/libstub/Makefile
index b1601aad7e1a..ba1e400960f5 100644
--- a/drivers/firmware/efi/libstub/Makefile
+++ b/drivers/firmware/efi/libstub/Makefile
@@ -83,7 +83,7 @@ lib-$(CONFIG_EFI_GENERIC_STUB) += efi-stub.o string.o intrinsics.o systable.o
lib-$(CONFIG_ARM) += arm32-stub.o
lib-$(CONFIG_ARM64) += arm64-stub.o
-lib-$(CONFIG_X86) += x86-stub.o
+lib-$(CONFIG_X86) += x86-stub.o x86-extract-direct.o
lib-$(CONFIG_RISCV) += riscv-stub.o
lib-$(CONFIG_LOONGARCH) += loongarch-stub.o
diff --git a/drivers/firmware/efi/libstub/x86-extract-direct.c b/drivers/firmware/efi/libstub/x86-extract-direct.c
new file mode 100644
index 000000000000..2d3107fd4623
--- /dev/null
+++ b/drivers/firmware/efi/libstub/x86-extract-direct.c
@@ -0,0 +1,204 @@
+// SPDX-License-Identifier: GPL-2.0-only
+
+#include <linux/acpi.h>
+#include <linux/efi.h>
+#include <linux/elf.h>
+#include <linux/stddef.h>
+
+#include <asm/efi.h>
+#include <asm/e820/types.h>
+#include <asm/desc.h>
+#include <asm/boot.h>
+#include <asm/bootparam_utils.h>
+#include <asm/shared/extract.h>
+#include <asm/shared/pgtable.h>
+
+#include "efistub.h"
+#include "x86-stub.h"
+
+static void do_puthex(unsigned long value)
+{
+ efi_printk("%08lx", value);
+}
+
+static void do_putstr(const char *msg)
+{
+ efi_printk("%s", msg);
+}
+
+static unsigned long do_map_range(unsigned long start,
+ unsigned long end,
+ unsigned int flags)
+{
+ efi_status_t status;
+
+ unsigned long size = end - start;
+
+ if (flags & MAP_ALLOC) {
+ if (start == (unsigned long)startup_32)
+ start = LOAD_PHYSICAL_ADDR;
+
+ unsigned long addr;
+
+ status = efi_low_alloc_above(size, CONFIG_PHYSICAL_ALIGN,
+ &addr, start);
+ if (status != EFI_SUCCESS)
+ efi_err("Unable to allocate memory for uncompressed kernel");
+
+ if (start != addr) {
+ efi_debug("Unable to allocate at given address"
+ " (desired=0x%lx, actual=0x%lx)",
+ (unsigned long)start, addr);
+ start = addr;
+ }
+ }
+
+ if ((flags & (MAP_PROTECT | MAP_ALLOC)) &&
+ IS_ENABLED(CONFIG_EFI_DXE_MEM_ATTRIBUTES)) {
+ unsigned long attr = 0;
+
+ if (!(flags & MAP_EXEC))
+ attr |= EFI_MEMORY_XP;
+
+ if (!(flags & MAP_WRITE))
+ attr |= EFI_MEMORY_RO;
+
+ status = efi_adjust_memory_range_protection(start, size, attr);
+ if (status != EFI_SUCCESS)
+ efi_err("Unable to protect memory range");
+ }
+
+ return start;
+}
+
+/*
+ * Trampoline takes 3 pages and can be loaded in first megabyte of memory
+ * with its end placed between 0 and 640k where BIOS might start.
+ * (see arch/x86/boot/compressed/pgtable_64.c)
+ */
+
+#ifdef CONFIG_64BIT
+static efi_status_t prepare_trampoline(void)
+{
+ efi_status_t status;
+
+ status = efi_allocate_pages(TRAMPOLINE_32BIT_SIZE,
+ (unsigned long *)&trampoline_32bit,
+ TRAMPOLINE_32BIT_PLACEMENT_MAX);
+
+ if (status != EFI_SUCCESS)
+ return status;
+
+ unsigned long trampoline_start = (unsigned long)trampoline_32bit;
+
+ memset(trampoline_32bit, 0, TRAMPOLINE_32BIT_SIZE);
+
+ if (IS_ENABLED(CONFIG_EFI_DXE_MEM_ATTRIBUTES)) {
+ /* First page of trampoline is a top level page table */
+ efi_adjust_memory_range_protection(trampoline_start,
+ PAGE_SIZE,
+ EFI_MEMORY_XP);
+ }
+
+ /* Second page of trampoline is the code (with a padding) */
+
+ void *caddr = (void *)trampoline_32bit + TRAMPOLINE_32BIT_CODE_OFFSET;
+
+ memcpy(caddr, trampoline_32bit_src, TRAMPOLINE_32BIT_CODE_SIZE);
+
+ if (IS_ENABLED(CONFIG_EFI_DXE_MEM_ATTRIBUTES)) {
+ efi_adjust_memory_range_protection((unsigned long)caddr,
+ PAGE_SIZE,
+ EFI_MEMORY_RO);
+
+ /* And the last page of trampoline is the stack */
+
+ efi_adjust_memory_range_protection(trampoline_start + 2 * PAGE_SIZE,
+ PAGE_SIZE,
+ EFI_MEMORY_XP);
+ }
+
+ return EFI_SUCCESS;
+}
+#else
+static inline efi_status_t prepare_trampoline(void)
+{
+ return EFI_SUCCESS;
+}
+#endif
+
+static efi_status_t init_loader_data(struct boot_params *params, struct efi_boot_memmap **map)
+{
+ struct efi_info *efi = (void *)¶ms->efi_info;
+ efi_status_t status;
+
+ status = efi_get_memory_map(map, false);
+
+ if (status != EFI_SUCCESS) {
+ efi_err("Unable to get EFI memory map...\n");
+ return status;
+ }
+
+ const char *signature = efi_is_64bit() ? EFI64_LOADER_SIGNATURE
+ : EFI32_LOADER_SIGNATURE;
+
+ memcpy(&efi->efi_loader_signature, signature, sizeof(__u32));
+
+ efi->efi_memdesc_size = (*map)->desc_size;
+ efi->efi_memdesc_version = (*map)->desc_ver;
+ efi->efi_memmap_size = (*map)->map_size;
+
+ efi_set_u64_split((unsigned long)(*map)->map,
+ &efi->efi_memmap, &efi->efi_memmap_hi);
+
+ efi_set_u64_split((unsigned long)efi_system_table,
+ &efi->efi_systab, &efi->efi_systab_hi);
+
+ return EFI_SUCCESS;
+}
+
+static void free_loader_data(struct boot_params *params, struct efi_boot_memmap *map)
+{
+ struct efi_info *efi = (void *)¶ms->efi_info;
+
+ efi_bs_call(free_pool, map);
+
+ efi->efi_memdesc_size = 0;
+ efi->efi_memdesc_version = 0;
+ efi->efi_memmap_size = 0;
+ efi_set_u64_split(0, &efi->efi_memmap, &efi->efi_memmap_hi);
+}
+
+extern unsigned char input_data[];
+extern unsigned int output_len, input_len;
+
+unsigned long extract_kernel_direct(struct boot_params *params)
+{
+
+ void *res;
+ efi_status_t status;
+ struct efi_extract_callbacks cb = { 0 };
+
+ status = prepare_trampoline();
+
+ if (status != EFI_SUCCESS)
+ return 0;
+
+ /* Prepare environment for do_extract_kernel() call */
+ struct efi_boot_memmap *map = NULL;
+ status = init_loader_data(params, &map);
+
+ if (status != EFI_SUCCESS)
+ return 0;
+
+ cb.puthex = do_puthex;
+ cb.putstr = do_putstr;
+ cb.map_range = do_map_range;
+
+ res = efi_extract_kernel(params, &cb, input_data, input_len,
+ (unsigned char *)startup_32, output_len);
+
+ free_loader_data(params, map);
+
+ return (unsigned long)res;
+}
diff --git a/drivers/firmware/efi/libstub/x86-stub.c b/drivers/firmware/efi/libstub/x86-stub.c
index 2fddb88613cd..8f172b688b0c 100644
--- a/drivers/firmware/efi/libstub/x86-stub.c
+++ b/drivers/firmware/efi/libstub/x86-stub.c
@@ -17,6 +17,7 @@
#include <asm/boot.h>
#include "efistub.h"
+#include "x86-stub.h"
/* Maximum physical address for 64-bit kernel with 4-level paging */
#define MAXMEM_X86_64_4LEVEL (1ull << 46)
@@ -212,55 +213,9 @@ static void retrieve_apple_device_properties(struct boot_params *boot_params)
}
}
-/*
- * Trampoline takes 2 pages and can be loaded in first megabyte of memory
- * with its end placed between 128k and 640k where BIOS might start.
- * (see arch/x86/boot/compressed/pgtable_64.c)
- *
- * We cannot find exact trampoline placement since memory map
- * can be modified by UEFI, and it can alter the computed address.
- */
-
-#define TRAMPOLINE_PLACEMENT_BASE ((128 - 8)*1024)
-#define TRAMPOLINE_PLACEMENT_SIZE (640*1024 - (128 - 8)*1024)
-
-void startup_32(struct boot_params *boot_params);
-
-static void
-setup_memory_protection(unsigned long image_base, unsigned long image_size)
-{
- /*
- * Allow execution of possible trampoline used
- * for switching between 4- and 5-level page tables
- * and relocated kernel image.
- */
-
- efi_adjust_memory_range_protection(TRAMPOLINE_PLACEMENT_BASE,
- TRAMPOLINE_PLACEMENT_SIZE, 0);
-
-#ifdef CONFIG_64BIT
- if (image_base != (unsigned long)startup_32)
- efi_adjust_memory_range_protection(image_base, image_size, 0);
-#else
- /*
- * Clear protection flags on a whole range of possible
- * addresses used for KASLR. We don't need to do that
- * on x86_64, since KASLR/extraction is performed after
- * dedicated identity page tables are built and we only
- * need to remove possible protection on relocated image
- * itself disregarding further relocations.
- */
- efi_adjust_memory_range_protection(LOAD_PHYSICAL_ADDR,
- KERNEL_IMAGE_SIZE - LOAD_PHYSICAL_ADDR,
- 0);
-#endif
-}
-
static const efi_char16_t apple[] = L"Apple";
-static void setup_quirks(struct boot_params *boot_params,
- unsigned long image_base,
- unsigned long image_size)
+static void setup_quirks(struct boot_params *boot_params)
{
efi_char16_t *fw_vendor = (efi_char16_t *)(unsigned long)
efi_table_attr(efi_system_table, fw_vendor);
@@ -269,9 +224,6 @@ static void setup_quirks(struct boot_params *boot_params,
if (IS_ENABLED(CONFIG_APPLE_PROPERTIES))
retrieve_apple_device_properties(boot_params);
}
-
- if (IS_ENABLED(CONFIG_EFI_DXE_MEM_ATTRIBUTES))
- setup_memory_protection(image_base, image_size);
}
/*
@@ -707,8 +659,7 @@ static efi_status_t exit_boot(struct boot_params *boot_params, void *handle)
}
/*
- * On success, we return the address of startup_32, which has potentially been
- * relocated by efi_relocate_kernel.
+ * On success, we return extracted kernel entry point.
* On failure, we exit to the firmware via efi_exit instead of returning.
*/
asmlinkage unsigned long efi_main(efi_handle_t handle,
@@ -733,60 +684,6 @@ asmlinkage unsigned long efi_main(efi_handle_t handle,
efi_dxe_table = NULL;
}
- /*
- * If the kernel isn't already loaded at a suitable address,
- * relocate it.
- *
- * It must be loaded above LOAD_PHYSICAL_ADDR.
- *
- * The maximum address for 64-bit is 1 << 46 for 4-level paging. This
- * is defined as the macro MAXMEM, but unfortunately that is not a
- * compile-time constant if 5-level paging is configured, so we instead
- * define our own macro for use here.
- *
- * For 32-bit, the maximum address is complicated to figure out, for
- * now use KERNEL_IMAGE_SIZE, which will be 512MiB, the same as what
- * KASLR uses.
- *
- * Also relocate it if image_offset is zero, i.e. the kernel wasn't
- * loaded by LoadImage, but rather by a bootloader that called the
- * handover entry. The reason we must always relocate in this case is
- * to handle the case of systemd-boot booting a unified kernel image,
- * which is a PE executable that contains the bzImage and an initrd as
- * COFF sections. The initrd section is placed after the bzImage
- * without ensuring that there are at least init_size bytes available
- * for the bzImage, and thus the compressed kernel's startup code may
- * overwrite the initrd unless it is moved out of the way.
- */
-
- buffer_start = ALIGN(bzimage_addr - image_offset,
- hdr->kernel_alignment);
- buffer_end = buffer_start + hdr->init_size;
-
- if ((buffer_start < LOAD_PHYSICAL_ADDR) ||
- (IS_ENABLED(CONFIG_X86_32) && buffer_end > KERNEL_IMAGE_SIZE) ||
- (IS_ENABLED(CONFIG_X86_64) && buffer_end > MAXMEM_X86_64_4LEVEL) ||
- (image_offset == 0)) {
- extern char _bss[];
-
- status = efi_relocate_kernel(&bzimage_addr,
- (unsigned long)_bss - bzimage_addr,
- hdr->init_size,
- hdr->pref_address,
- hdr->kernel_alignment,
- LOAD_PHYSICAL_ADDR);
- if (status != EFI_SUCCESS) {
- efi_err("efi_relocate_kernel() failed!\n");
- goto fail;
- }
- /*
- * Now that we've copied the kernel elsewhere, we no longer
- * have a set up block before startup_32(), so reset image_offset
- * to zero in case it was set earlier.
- */
- image_offset = 0;
- }
-
#ifdef CONFIG_CMDLINE_BOOL
status = efi_parse_options(CONFIG_CMDLINE);
if (status != EFI_SUCCESS) {
@@ -843,7 +740,11 @@ asmlinkage unsigned long efi_main(efi_handle_t handle,
setup_efi_pci(boot_params);
- setup_quirks(boot_params, bzimage_addr, buffer_end - buffer_start);
+ setup_quirks(boot_params);
+
+ bzimage_addr = extract_kernel_direct(boot_params);
+ if (!bzimage_addr)
+ goto fail;
status = exit_boot(boot_params, handle);
if (status != EFI_SUCCESS) {
diff --git a/drivers/firmware/efi/libstub/x86-stub.h b/drivers/firmware/efi/libstub/x86-stub.h
new file mode 100644
index 000000000000..5fbc743eb367
--- /dev/null
+++ b/drivers/firmware/efi/libstub/x86-stub.h
@@ -0,0 +1,11 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+
+#ifndef _DRIVERS_FIRMWARE_EFI_X86STUB_H
+#define _DRIVERS_FIRMWARE_EFI_X86STUB_H
+
+#include <asm/bootparam.h>
+
+unsigned long extract_kernel_direct(struct boot_params *boot_params);
+void startup_32(struct boot_params *boot_params);
+
+#endif
--
2.37.4
On 10/25/2022 09:12, Evgeniy Baskov wrote:
> This patchset is aimed
> * to improve UEFI compatibility of compressed kernel code for x86_64
> * to setup proper memory access attributes for code and rodata sections
> * to implement W^X protection policy throughout the whole execution
> of compressed kernel for EFISTUB code path.
>
> Kernel is made to be more compatible with PE image specification [3],
> allowing it to be successfully loaded by stricter PE loader
> implementations like the one from [2]. There is at least one
> known implementation that uses that loader in production [4].
> There are also ongoing efforts to upstream these changes.
>
> Also the patchset adds EFI_MEMORY_ATTTRIBUTE_PROTOCOL, included into
> EFI specification since version 2.10, as a better alternative to
> using DXE services for memory protection attributes manipulation,
> since it is defined by the UEFI specification itself and not UEFI PI
> specification. This protocol is not widely available so the code
> using DXE services is kept in place as a fallback in case specific
> implementation does not support the new protocol.
> One of EFI implementations that already support
> EFI_MEMORY_ATTTRIBUTE_PROTOCOL is Microsoft Project Mu [5].
>
> Kernel image generation tool (tools/build.c) is refactored as a part
> of changes that makes PE image more compatible.
>
> The patchset implements memory protection for compressed kernel
> code while executing both inside EFI boot services and outside of
> them. For EFISTUB code path W^X protection policy is maintained
> throughout the whole execution of compressed kernel. The latter
> is achieved by extracting the kernel directly from EFI environment
> and jumping to it's head immediately after exiting EFI boot services.
> As a side effect of this change one page table rebuild and a copy of
> the kernel image is removed.
>
> Direct extraction can be toggled using CONFIG_EFI_STUB_EXTRACT_DIRECT.
> Memory protection inside EFI environment is controlled by the
> CONFIG_DXE_MEM_ATTRIBUTES option, although with these patches this
> option also control the use EFI_MEMORY_ATTTRIBUTE_PROTOCOL and memory
> protection attributes of PE sections and not only DXE services as the
> name might suggest.
>
> Changes in v2:
> * Fix spelling.
> * Rebase code to current master.
> * Split huge patches into smaller ones.
> * Remove unneeded forward declarations.
> * Make direct extraction unconditional.
> * Also make it work for x86_32.
> * Reduce lower limit of KASLR to 64M.
> * Make callback interface more logically consistent.
> * Actually declare callbacks structure before using it.
> * Mention effect on x86_32 in commit message of
> "x86/build: Remove RWX sections and align on 4KB".
> * Clarify commit message of
> "x86/boot: Increase boot page table size".
> * Remove "startup32_" prefix on startup32_enable_nx_if_supported.
> * Move linker generated sections outside of function scope.
> * Drop some unintended changes.
> * Drop generating 2 reloc entries.
> (as I've misread the documentation and there's no need for this change.)
> * Set has_nx from enable_nx_if_supported correctly.
> * Move ELF header check to build time.
> * Set WP at the same time as PG in trampoline code,
> as it is more logically consistent.
> * Put x86-specific EFISTUB definitions in x86-stub.h header.
> * Catch presence of ELF segments violating W^X during build.
> * Move PE definitions from build.c to a new header file.
> * Fix generation of PE '.compat' section.
>
> I decided to keep protection of compressed kernel blob and '.rodata'
> separate from '.text' for now, since it does not really have a lot
> of overhead.
>
> Otherwise, all comments on v1 seems to be addressed. Please also apply
> Peter's patch [6] on top of this series.
>
> Patch "x86/boot: Support 4KB pages for identity mapping" needs review
> from x86/mm team.
>
> [1] https://lkml.org/lkml/2022/8/1/1314
> [2] https://github.com/acidanthera/audk/tree/secure_pe
> [3] https://download.microsoft.com/download/9/c/5/9c5b2167-8017-4bae-9fde-d599bac8184a/pecoff_v83.docx
> [4] https://www.ispras.ru/en/technologies/asperitas/
> [5] https://github.com/microsoft/mu_tiano_platforms
> [6] https://lkml.org/lkml/2022/10/18/1178
>
> Evgeniy Baskov (23):
> x86/boot: Align vmlinuz sections on page size
> x86/build: Remove RWX sections and align on 4KB
> x86/boot: Set cr0 to known state in trampoline
> x86/boot: Increase boot page table size
> x86/boot: Support 4KB pages for identity mapping
> x86/boot: Setup memory protection for bzImage code
> x86/build: Check W^X of vmlinux during build
> x86/boot: Map memory explicitly
> x86/boot: Remove mapping from page fault handler
> efi/libstub: Move helper function to related file
> x86/boot: Make console interface more abstract
> x86/boot: Make kernel_add_identity_map() a pointer
> x86/boot: Split trampoline and pt init code
> x86/boot: Add EFI kernel extraction interface
> efi/x86: Support extracting kernel from libstub
> x86/boot: Reduce lower limit of physical KASLR
> x86/boot: Reduce size of the DOS stub
> tools/include: Add simplified version of pe.h
> x86/build: Cleanup tools/build.c
> x86/build: Make generated PE more spec compliant
> efi/x86: Explicitly set sections memory attributes
> efi/libstub: Add memory attribute protocol definitions
> efi/libstub: Use memory attribute protocol
>
> arch/x86/boot/Makefile | 2 +-
> arch/x86/boot/compressed/Makefile | 8 +-
> arch/x86/boot/compressed/acpi.c | 21 +-
> arch/x86/boot/compressed/efi.c | 19 +-
> arch/x86/boot/compressed/head_32.S | 44 +-
> arch/x86/boot/compressed/head_64.S | 76 ++-
> arch/x86/boot/compressed/ident_map_64.c | 122 ++--
> arch/x86/boot/compressed/kaslr.c | 8 +-
> arch/x86/boot/compressed/misc.c | 279 ++++-----
> arch/x86/boot/compressed/misc.h | 23 +-
> arch/x86/boot/compressed/pgtable.h | 20 -
> arch/x86/boot/compressed/pgtable_64.c | 75 ++-
> arch/x86/boot/compressed/putstr.c | 130 ++++
> arch/x86/boot/compressed/sev.c | 6 +-
> arch/x86/boot/compressed/vmlinux.lds.S | 6 +
> arch/x86/boot/header.S | 110 +---
> arch/x86/boot/tools/build.c | 573 +++++++++++-------
> arch/x86/include/asm/boot.h | 26 +-
> arch/x86/include/asm/efi.h | 7 +
> arch/x86/include/asm/init.h | 1 +
> arch/x86/include/asm/shared/extract.h | 27 +
> arch/x86/include/asm/shared/pgtable.h | 29 +
> arch/x86/kernel/vmlinux.lds.S | 15 +-
> arch/x86/mm/ident_map.c | 185 +++++-
> drivers/firmware/efi/Kconfig | 2 +
> drivers/firmware/efi/libstub/Makefile | 2 +-
> drivers/firmware/efi/libstub/efistub.h | 26 +
> drivers/firmware/efi/libstub/mem.c | 190 ++++++
> .../firmware/efi/libstub/x86-extract-direct.c | 204 +++++++
> drivers/firmware/efi/libstub/x86-stub.c | 231 ++-----
> drivers/firmware/efi/libstub/x86-stub.h | 11 +
> include/linux/efi.h | 1 +
> tools/include/linux/pe.h | 150 +++++
> 33 files changed, 1848 insertions(+), 781 deletions(-)
> delete mode 100644 arch/x86/boot/compressed/pgtable.h
> create mode 100644 arch/x86/boot/compressed/putstr.c
> create mode 100644 arch/x86/include/asm/shared/extract.h
> create mode 100644 arch/x86/include/asm/shared/pgtable.h
> create mode 100644 drivers/firmware/efi/libstub/x86-extract-direct.c
> create mode 100644 drivers/firmware/efi/libstub/x86-stub.h
> create mode 100644 tools/include/linux/pe.h
>
Hi,
I was talking to Peter Jones recently about what was still missing for
NX support in the kernel and he pointed me at this series.
So I had a try with this series on top of:
ee6050c8af96 ("Merge tag 'ata-6.1-rc4' of
git://git.kernel.org/pub/scm/linux/kernel/git/dlemoal/libata")
Unfortunately I can't boot the system with this series applied.
This is not on a system that enforces NX pre-boot (but that was my goal
after I could prove booting on something that doesn't).
I didn't apply Peter's patch 6 you referenced in your cover letter, but
I don't expect that's the reason for the failure.
I get:
"Failed to allocate space for tmp_cmdline"
-- System Halted
This is early enough [1] that I don't have anything else output to a
serial log from the kernel.
https://github.com/torvalds/linux/blob/d4013bc4d49f6da8178a340348369bb9920225c9/arch/x86/boot/compressed/kaslr.c#L268
Since this is only in the kaslr path, I tried to turn that off with
'nokaslr' on the kernel command line.
I then get a failure of:
"Out of memory while allocating zstd_dctx"
-- System Halted
This kernel was booted from the following path:
-> Insyde BIOS
--> shim (from Fedora 36 repository)
---> GRUB (from Peter for Fedora 36 w/ some level NX support)
----> kernel binary (self-built)
The BIOS on this system doesn't validate NX, but also the shim binary
did not have the NX bit set in the PE header.
Your cover letter referenced CONFIG_EFI_STUB_EXTRACT_DIRECT but I didn't
find this option in the series. I also tried both with
CONFIG_EFI_DXE_MEM_ATTRIBUTES=y or unset, same result.
On 2022-11-04 21:21, Limonciello, Mario wrote:
> On 10/25/2022 09:12, Evgeniy Baskov wrote:
>> ...
>>
>
> Hi,
>
> I was talking to Peter Jones recently about what was still missing for
> NX support in the kernel and he pointed me at this series.
>
> So I had a try with this series on top of:
>
> ee6050c8af96 ("Merge tag 'ata-6.1-rc4' of
> git://git.kernel.org/pub/scm/linux/kernel/git/dlemoal/libata")
>
> Unfortunately I can't boot the system with this series applied.
> This is not on a system that enforces NX pre-boot (but that was my
> goal after I could prove booting on something that doesn't).
> I didn't apply Peter's patch 6 you referenced in your cover letter,
> but I don't expect that's the reason for the failure.
>
> I get:
>
> "Failed to allocate space for tmp_cmdline"
>
> -- System Halted
>
> This is early enough [1] that I don't have anything else output to a
> serial log from the kernel.
>
> https://github.com/torvalds/linux/blob/d4013bc4d49f6da8178a340348369bb9920225c9/arch/x86/boot/compressed/kaslr.c#L268
>
> Since this is only in the kaslr path, I tried to turn that off with
> 'nokaslr' on the kernel command line.
>
> I then get a failure of:
>
> "Out of memory while allocating zstd_dctx"
>
> -- System Halted
>
> This kernel was booted from the following path:
> -> Insyde BIOS
> --> shim (from Fedora 36 repository)
> ---> GRUB (from Peter for Fedora 36 w/ some level NX support)
> ----> kernel binary (self-built)
>
> The BIOS on this system doesn't validate NX, but also the shim binary
> did not have the NX bit set in the PE header.
>
> Your cover letter referenced CONFIG_EFI_STUB_EXTRACT_DIRECT but I
> didn't find this option in the series. I also tried both with
> CONFIG_EFI_DXE_MEM_ATTRIBUTES=y or unset, same result.
Hi,
Thanks for your feedback!
CONFIG_EFI_STUB_EXTRACT_DIRECT option was removed in v2 of the series
and direct extraction is unconditional now.
You are getting really weird errors, which unfortunately I am unable
to reproduce yet. I've tried booting with fedora's grub and the series
applied on top of ee6050c8af96, but it did boot successfully.
From the error messages it's some problem with malloc() implementation
of compressed kernel code. I suspect that malloc_ptr inside .bss is not
zeroed. This should not happen when booting via either non-UEFI
interface, or via UEFI (when kernel is properly loaded as PE image).
The problem, I think, arises when kernel is loaded as a blob, but EFI
handover protocol is used to start its execution. This is what grub
seems to be doing.
Can you please try booting with patches below applied on top?
If this fixes the problem, I'll include these changes in v3.
Thanks,
Evgeniy Baskov
--
diff --git a/arch/x86/boot/compressed/head_32.S
b/arch/x86/boot/compressed/head_32.S
index 9871cc8466fb..69811d9ab4ce 100644
--- a/arch/x86/boot/compressed/head_32.S
+++ b/arch/x86/boot/compressed/head_32.S
@@ -152,6 +152,14 @@ SYM_FUNC_END(startup_32)
#ifdef CONFIG_EFI_STUB
SYM_FUNC_START(efi32_stub_entry)
+ /* Clear BSS */
+ xorl %eax, %eax
+ leal _bss@GOTOFF(%ebx), %edi
+ leal _ebss@GOTOFF(%ebx), %ecx
+ subl %edi, %ecx
+ shrl $2, %ecx
+ rep stosl
+
add $0x4, %esp
movl 8(%esp), %esi /* save boot_params pointer */
call efi_main
diff --git a/arch/x86/boot/compressed/head_64.S
b/arch/x86/boot/compressed/head_64.S
index 2bb0e6da08c0..384706d12354 100644
--- a/arch/x86/boot/compressed/head_64.S
+++ b/arch/x86/boot/compressed/head_64.S
@@ -553,8 +553,20 @@ SYM_CODE_END(startup_64)
#ifdef CONFIG_EFI_STUB
.org 0x390
SYM_FUNC_START(efi64_stub_entry)
+ /* Preserve first parameter */
+ movq %rdi, %r10
+
+ /* Clear BSS */
+ xorl %eax, %eax
+ leaq _bss(%rip), %rdi
+ leaq _ebss(%rip), %rcx
+ subq %rdi, %rcx
+ shrq $3, %rcx
+ rep stosq
+
and $~0xf, %rsp /* realign the stack */
movq %rdx, %rbx /* save boot_params pointer */
+ movq %r10, %rdi
call efi_main
cld
diff --git a/drivers/firmware/efi/libstub/x86-stub.c
b/drivers/firmware/efi/libstub/x86-stub.c
index 95a69c37518e..1a2c52e77c6e 100644
--- a/drivers/firmware/efi/libstub/x86-stub.c
+++ b/drivers/firmware/efi/libstub/x86-stub.c
@@ -24,7 +24,7 @@
const efi_system_table_t *efi_system_table;
extern u32 image_offset;
-static efi_loaded_image_t *image = NULL;
+static efi_loaded_image_t *image __section(".data");
extern char _head[], _ehead[];
extern char _compressed[], _ecompressed[];
On 11/8/2022 01:01, Evgeniy Baskov wrote:
> On 2022-11-04 21:21, Limonciello, Mario wrote:
>> On 10/25/2022 09:12, Evgeniy Baskov wrote:
>>> ...
>>>
>>
>> Hi,
>>
>> I was talking to Peter Jones recently about what was still missing for
>> NX support in the kernel and he pointed me at this series.
>>
>> So I had a try with this series on top of:
>>
>> ee6050c8af96 ("Merge tag 'ata-6.1-rc4' of
>> git://git.kernel.org/pub/scm/linux/kernel/git/dlemoal/libata")
>>
>> Unfortunately I can't boot the system with this series applied.
>> This is not on a system that enforces NX pre-boot (but that was my
>> goal after I could prove booting on something that doesn't).
>> I didn't apply Peter's patch 6 you referenced in your cover letter,
>> but I don't expect that's the reason for the failure.
>>
>> I get:
>>
>> "Failed to allocate space for tmp_cmdline"
>>
>> -- System Halted
>>
>> This is early enough [1] that I don't have anything else output to a
>> serial log from the kernel.
>>
>> https://nam11.safelinks.protection.outlook.com/?url=https%3A%2F%2Fgithub.com%2Ftorvalds%2Flinux%2Fblob%2Fd4013bc4d49f6da8178a340348369bb9920225c9%2Farch%2Fx86%2Fboot%2Fcompressed%2Fkaslr.c%23L268&data=05%7C01%7Cmario.limonciello%40amd.com%7C9280e92e85bc4e2b52cd08dac15704a5%7C3dd8961fe4884e608e11a82d994e183d%7C0%7C0%7C638034876740462327%7CUnknown%7CTWFpbGZsb3d8eyJWIjoiMC4wLjAwMDAiLCJQIjoiV2luMzIiLCJBTiI6Ik1haWwiLCJXVCI6Mn0%3D%7C3000%7C%7C%7C&sdata=oiCJUa8M3x%2FYCxVjJj98R7iU%2FzIj%2FQxdVOWbnqGWCNI%3D&reserved=0
>>
>> Since this is only in the kaslr path, I tried to turn that off with
>> 'nokaslr' on the kernel command line.
>>
>> I then get a failure of:
>>
>> "Out of memory while allocating zstd_dctx"
>>
>> -- System Halted
>>
>> This kernel was booted from the following path:
>> -> Insyde BIOS
>> --> shim (from Fedora 36 repository)
>> ---> GRUB (from Peter for Fedora 36 w/ some level NX support)
>> ----> kernel binary (self-built)
>>
>> The BIOS on this system doesn't validate NX, but also the shim binary
>> did not have the NX bit set in the PE header.
>>
>> Your cover letter referenced CONFIG_EFI_STUB_EXTRACT_DIRECT but I
>> didn't find this option in the series. I also tried both with
>> CONFIG_EFI_DXE_MEM_ATTRIBUTES=y or unset, same result.
>
> Hi,
>
> Thanks for your feedback!
>
Sure!
> CONFIG_EFI_STUB_EXTRACT_DIRECT option was removed in v2 of the series
> and direct extraction is unconditional now.
>
> You are getting really weird errors, which unfortunately I am unable
> to reproduce yet. I've tried booting with fedora's grub and the series
> applied on top of ee6050c8af96, but it did boot successfully.
Well so I expect the unique difference is that I'm using Peter's GRUB
that has some NX support landed. He has binaries for it here:
https://blog.uncooperative.org/~pjones/nx/repo/
*Theoretically* a BIOS that enforces NX should be able to boot a shim with
the NX compat bit set which should be able to boot that GRUB supporting
NX which should be able to boot this series.
>
> From the error messages it's some problem with malloc() implementation
> of compressed kernel code. I suspect that malloc_ptr inside .bss is not
> zeroed. This should not happen when booting via either non-UEFI
> interface, or via UEFI (when kernel is properly loaded as PE image).
> The problem, I think, arises when kernel is loaded as a blob, but EFI
> handover protocol is used to start its execution. This is what grub
> seems to be doing.
>
> Can you please try booting with patches below applied on top?
> If this fixes the problem, I'll include these changes in v3.
Yup, spot on. I can the kernel from Peter's NX enabled GRUB now with:
* 6.1-rc4
* Your existing 23 patch series
* this new patch
Thanks!!
Would you mind CC me when you submit v3? As I have an interest in
seeing NX support I'd like to continue to follow along on the series.
Anything in the series you don't change in any material way from v2
please feel free to include:
Tested-by: Mario Limonciello <[email protected]>
>
> Thanks,
> Evgeniy Baskov
> --
> diff --git a/arch/x86/boot/compressed/head_32.S
> b/arch/x86/boot/compressed/head_32.S
> index 9871cc8466fb..69811d9ab4ce 100644
> --- a/arch/x86/boot/compressed/head_32.S
> +++ b/arch/x86/boot/compressed/head_32.S
> @@ -152,6 +152,14 @@ SYM_FUNC_END(startup_32)
>
> #ifdef CONFIG_EFI_STUB
> SYM_FUNC_START(efi32_stub_entry)
> + /* Clear BSS */
> + xorl %eax, %eax
> + leal _bss@GOTOFF(%ebx), %edi
> + leal _ebss@GOTOFF(%ebx), %ecx
> + subl %edi, %ecx
> + shrl $2, %ecx
> + rep stosl
> +
> add $0x4, %esp
> movl 8(%esp), %esi /* save boot_params pointer */
> call efi_main
> diff --git a/arch/x86/boot/compressed/head_64.S
> b/arch/x86/boot/compressed/head_64.S
> index 2bb0e6da08c0..384706d12354 100644
> --- a/arch/x86/boot/compressed/head_64.S
> +++ b/arch/x86/boot/compressed/head_64.S
> @@ -553,8 +553,20 @@ SYM_CODE_END(startup_64)
> #ifdef CONFIG_EFI_STUB
> .org 0x390
> SYM_FUNC_START(efi64_stub_entry)
> + /* Preserve first parameter */
> + movq %rdi, %r10
> +
> + /* Clear BSS */
> + xorl %eax, %eax
> + leaq _bss(%rip), %rdi
> + leaq _ebss(%rip), %rcx
> + subq %rdi, %rcx
> + shrq $3, %rcx
> + rep stosq
> +
> and $~0xf, %rsp /* realign the stack */
> movq %rdx, %rbx /* save boot_params pointer */
> + movq %r10, %rdi
> call efi_main
>
> cld
> diff --git a/drivers/firmware/efi/libstub/x86-stub.c
> b/drivers/firmware/efi/libstub/x86-stub.c
> index 95a69c37518e..1a2c52e77c6e 100644
> --- a/drivers/firmware/efi/libstub/x86-stub.c
> +++ b/drivers/firmware/efi/libstub/x86-stub.c
> @@ -24,7 +24,7 @@
>
> const efi_system_table_t *efi_system_table;
> extern u32 image_offset;
> -static efi_loaded_image_t *image = NULL;
> +static efi_loaded_image_t *image __section(".data");
>
> extern char _head[], _ehead[];
> extern char _compressed[], _ecompressed[];
On 2022-11-08 21:17, Limonciello, Mario wrote:
> On 11/8/2022 01:01, Evgeniy Baskov wrote:
>> On 2022-11-04 21:21, Limonciello, Mario wrote:
>>> On 10/25/2022 09:12, Evgeniy Baskov wrote:
>>>> ...
>>>>
>>>
>>> Hi,
>>>
>>> I was talking to Peter Jones recently about what was still missing
>>> for
>>> NX support in the kernel and he pointed me at this series.
>>>
>>> So I had a try with this series on top of:
>>>
>>> ee6050c8af96 ("Merge tag 'ata-6.1-rc4' of
>>> git://git.kernel.org/pub/scm/linux/kernel/git/dlemoal/libata")
>>>
>>> Unfortunately I can't boot the system with this series applied.
>>> This is not on a system that enforces NX pre-boot (but that was my
>>> goal after I could prove booting on something that doesn't).
>>> I didn't apply Peter's patch 6 you referenced in your cover letter,
>>> but I don't expect that's the reason for the failure.
>>>
>>> I get:
>>>
>>> "Failed to allocate space for tmp_cmdline"
>>>
>>> -- System Halted
>>>
>>> This is early enough [1] that I don't have anything else output to a
>>> serial log from the kernel.
>>>
>>> https://nam11.safelinks.protection.outlook.com/?url=https%3A%2F%2Fgithub.com%2Ftorvalds%2Flinux%2Fblob%2Fd4013bc4d49f6da8178a340348369bb9920225c9%2Farch%2Fx86%2Fboot%2Fcompressed%2Fkaslr.c%23L268&data=05%7C01%7Cmario.limonciello%40amd.com%7C9280e92e85bc4e2b52cd08dac15704a5%7C3dd8961fe4884e608e11a82d994e183d%7C0%7C0%7C638034876740462327%7CUnknown%7CTWFpbGZsb3d8eyJWIjoiMC4wLjAwMDAiLCJQIjoiV2luMzIiLCJBTiI6Ik1haWwiLCJXVCI6Mn0%3D%7C3000%7C%7C%7C&sdata=oiCJUa8M3x%2FYCxVjJj98R7iU%2FzIj%2FQxdVOWbnqGWCNI%3D&reserved=0
>>>
>>> Since this is only in the kaslr path, I tried to turn that off with
>>> 'nokaslr' on the kernel command line.
>>>
>>> I then get a failure of:
>>>
>>> "Out of memory while allocating zstd_dctx"
>>>
>>> -- System Halted
>>>
>>> This kernel was booted from the following path:
>>> -> Insyde BIOS
>>> --> shim (from Fedora 36 repository)
>>> ---> GRUB (from Peter for Fedora 36 w/ some level NX support)
>>> ----> kernel binary (self-built)
>>>
>>> The BIOS on this system doesn't validate NX, but also the shim binary
>>> did not have the NX bit set in the PE header.
>>>
>>> Your cover letter referenced CONFIG_EFI_STUB_EXTRACT_DIRECT but I
>>> didn't find this option in the series. I also tried both with
>>> CONFIG_EFI_DXE_MEM_ATTRIBUTES=y or unset, same result.
>>
>> Hi,
>>
>> Thanks for your feedback!
>>
>
> Sure!
>
>> CONFIG_EFI_STUB_EXTRACT_DIRECT option was removed in v2 of the series
>> and direct extraction is unconditional now.
>>
>> You are getting really weird errors, which unfortunately I am unable
>> to reproduce yet. I've tried booting with fedora's grub and the series
>> applied on top of ee6050c8af96, but it did boot successfully.
>
> Well so I expect the unique difference is that I'm using Peter's GRUB
> that has some NX support landed. He has binaries for it here:
>
> https://blog.uncooperative.org/~pjones/nx/repo/
>
> *Theoretically* a BIOS that enforces NX should be able to boot a shim
> with
> the NX compat bit set which should be able to boot that GRUB
> supporting NX which should be able to boot this series.
>
>>
>> From the error messages it's some problem with malloc()
>> implementation
>> of compressed kernel code. I suspect that malloc_ptr inside .bss is
>> not
>> zeroed. This should not happen when booting via either non-UEFI
>> interface, or via UEFI (when kernel is properly loaded as PE image).
>> The problem, I think, arises when kernel is loaded as a blob, but EFI
>> handover protocol is used to start its execution. This is what grub
>> seems to be doing.
>>
>> Can you please try booting with patches below applied on top?
>> If this fixes the problem, I'll include these changes in v3.
>
> Yup, spot on. I can the kernel from Peter's NX enabled GRUB now with:
> * 6.1-rc4
> * Your existing 23 patch series
> * this new patch
>
> Thanks!!
>
> Would you mind CC me when you submit v3? As I have an interest in
> seeing NX support I'd like to continue to follow along on the series.
Ok.
>
> Anything in the series you don't change in any material way from v2
> please feel free to include:
>
> Tested-by: Mario Limonciello <[email protected]>
>
Great, thanks!
Hi Evgeniy,
Thanks for your effort!
On Tue, Oct 25, 2022 at 05:12:38PM +0300, Evgeniy Baskov wrote:
> This patchset is aimed
> * to improve UEFI compatibility of compressed kernel code for x86_64
> * to setup proper memory access attributes for code and rodata sections
> * to implement W^X protection policy throughout the whole execution
> of compressed kernel for EFISTUB code path.
>
> Kernel is made to be more compatible with PE image specification [3],
> allowing it to be successfully loaded by stricter PE loader
> implementations like the one from [2]. There is at least one
> known implementation that uses that loader in production [4].
> There are also ongoing efforts to upstream these changes.
>
> Also the patchset adds EFI_MEMORY_ATTTRIBUTE_PROTOCOL, included into
> EFI specification since version 2.10, as a better alternative to
> using DXE services for memory protection attributes manipulation,
> since it is defined by the UEFI specification itself and not UEFI PI
> specification. This protocol is not widely available so the code
> using DXE services is kept in place as a fallback in case specific
> implementation does not support the new protocol.
> One of EFI implementations that already support
> EFI_MEMORY_ATTTRIBUTE_PROTOCOL is Microsoft Project Mu [5].
>
Because Peter Jones point out this patchset to me, so I tried it
on OVMF, and I set the EfiLoaderData in DXE memory protection policy:
Index: edk2/MdeModulePkg/MdeModulePkg.dec
===================================================================
--- edk2.orig/MdeModulePkg/MdeModulePkg.dec
+++ edk2/MdeModulePkg/MdeModulePkg.dec
@@ -1392,7 +1392,7 @@
# e.g. 0x7BD4 can be used for all memory except Code and ACPINVS/Reserved. <BR>
#
# @Prompt Set DXE memory protection policy.
- gEfiMdeModulePkgTokenSpaceGuid.PcdDxeNxMemoryProtectionPolicy|0x0000000|UINT64|0x00001048^M
+ gEfiMdeModulePkgTokenSpaceGuid.PcdDxeNxMemoryProtectionPolicy|0x0000004|UINT64|0x00001048^M
## PCI Serial Device Info. It is an array of Device, Function, and Power Management
# information that describes the path that contains zero or more PCI to PCI bridges
I applied this v2 patch set on top of v6.1-rc5 kernel, and boot with a shim which
set the PE NX-compatibility DLL Characteristic flag. I got a page fault exception:
Loading Linux 6.1.0-rc5-default+ ...
Loading initial ramdisk ...
!!!! X64 Exception Type - 0E(#PF - Page-Fault) CPU Apic ID - 00000000 !!!!
ExceptionData - 0000000000000011 I:1 R:0 U:0 W:0 P:1 PK:0 SS:0 SGX:0
RIP - 0000000076A3C390, CS - 0000000000000038, RFLAGS - 0000000000210202
RAX - 000000007D8CCDF8, RCX - 0000000076A3C390, RDX - 000000007DE86000
RBX - 0000000076A3C000, RSP - 000000007FF0D2C8, RBP - 000000007DE86000
RSI - 000000007F9EE018, RDI - 000000007DFD1C18
R8 - 0000000076A3C000, R9 - 0000000000000190, R10 - 000000007FF1D658
R11 - 0000000000000004, R12 - 0000000000000190, R13 - 000000007D8CCE00
R14 - 000000007D8C76B4, R15 - 000000007BF0CBD5
DS - 0000000000000030, ES - 0000000000000030, FS - 0000000000000030
GS - 0000000000000030, SS - 0000000000000030
CR0 - 0000000080010033, CR2 - 0000000076A3C390, CR3 - 000000007FC01000
CR4 - 0000000000000668, CR8 - 0000000000000000
DR0 - 0000000000000000, DR1 - 0000000000000000, DR2 - 0000000000000000
DR3 - 0000000000000000, DR6 - 00000000FFFF0FF0, DR7 - 0000000000000400
GDTR - 000000007F9DE000 0000000000000047, LDTR - 0000000000000000
IDTR - 000000007F2E9018 0000000000000FFF, TR - 0000000000000000
FXSAVE_STATE - 000000007FF0CF20
!!!! Find image based on IP(0x7BF0BAB5) /mnt/working/source_code-git/edk2/Build/OvmfX64/DEBUG_GCC5/X64/MdeModulePkg/Universal/Variable/RuntimeDxe/VariableRuntimeDxe/DEBUG/VariableRuntimeDxe.dll (ImageBase=0000000000F40E7C, EntryPoint=0000000000F767B8) !!!!
My question is: Can I just set EfiLoaderData in DXE memory protection policy
in EDK2/OVMF to test this patchset? Or which platform (virtual or physical)
can we use for testing?
Thanks a lot!
Joey Lee
On 2022-11-20 04:49, joeyli wrote:
> Hi Evgeniy,
>
> Thanks for your effort!
>
> On Tue, Oct 25, 2022 at 05:12:38PM +0300, Evgeniy Baskov wrote:
...
>
> Because Peter Jones point out this patchset to me, so I tried it
> on OVMF, and I set the EfiLoaderData in DXE memory protection policy:
>
> Index: edk2/MdeModulePkg/MdeModulePkg.dec
> ===================================================================
> --- edk2.orig/MdeModulePkg/MdeModulePkg.dec
> +++ edk2/MdeModulePkg/MdeModulePkg.dec
> @@ -1392,7 +1392,7 @@
> # e.g. 0x7BD4 can be used for all memory except Code and
> ACPINVS/Reserved. <BR>
> #
> # @Prompt Set DXE memory protection policy.
> -
> gEfiMdeModulePkgTokenSpaceGuid.PcdDxeNxMemoryProtectionPolicy|0x0000000|UINT64|0x00001048^M
> +
> gEfiMdeModulePkgTokenSpaceGuid.PcdDxeNxMemoryProtectionPolicy|0x0000004|UINT64|0x00001048^M
>
> ## PCI Serial Device Info. It is an array of Device, Function, and
> Power Management
> # information that describes the path that contains zero or more
> PCI to PCI bridges
>
>
> I applied this v2 patch set on top of v6.1-rc5 kernel, and boot with a
> shim which
> set the PE NX-compatibility DLL Characteristic flag. I got a page
> fault exception:
>
> Loading Linux 6.1.0-rc5-default+ ...
> Loading initial ramdisk ...
> !!!! X64 Exception Type - 0E(#PF - Page-Fault) CPU Apic ID - 00000000
> !!!!
> ExceptionData - 0000000000000011 I:1 R:0 U:0 W:0 P:1 PK:0 SS:0 SGX:0
> RIP - 0000000076A3C390, CS - 0000000000000038, RFLAGS -
> 0000000000210202
> RAX - 000000007D8CCDF8, RCX - 0000000076A3C390, RDX - 000000007DE86000
> RBX - 0000000076A3C000, RSP - 000000007FF0D2C8, RBP - 000000007DE86000
> RSI - 000000007F9EE018, RDI - 000000007DFD1C18
> R8 - 0000000076A3C000, R9 - 0000000000000190, R10 - 000000007FF1D658
> R11 - 0000000000000004, R12 - 0000000000000190, R13 - 000000007D8CCE00
> R14 - 000000007D8C76B4, R15 - 000000007BF0CBD5
> DS - 0000000000000030, ES - 0000000000000030, FS - 0000000000000030
> GS - 0000000000000030, SS - 0000000000000030
> CR0 - 0000000080010033, CR2 - 0000000076A3C390, CR3 - 000000007FC01000
> CR4 - 0000000000000668, CR8 - 0000000000000000
> DR0 - 0000000000000000, DR1 - 0000000000000000, DR2 - 0000000000000000
> DR3 - 0000000000000000, DR6 - 00000000FFFF0FF0, DR7 - 0000000000000400
> GDTR - 000000007F9DE000 0000000000000047, LDTR - 0000000000000000
> IDTR - 000000007F2E9018 0000000000000FFF, TR - 0000000000000000
> FXSAVE_STATE - 000000007FF0CF20
> !!!! Find image based on IP(0x7BF0BAB5)
> /mnt/working/source_code-git/edk2/Build/OvmfX64/DEBUG_GCC5/X64/MdeModulePkg/Universal/Variable/RuntimeDxe/VariableRuntimeDxe/DEBUG/VariableRuntimeDxe.dll
> (ImageBase=0000000000F40E7C, EntryPoint=0000000000F767B8) !!!!
>
>
> My question is: Can I just set EfiLoaderData in DXE memory protection
> policy
> in EDK2/OVMF to test this patchset? Or which platform (virtual or
> physical)
> can we use for testing?
>
> Thanks a lot!
> Joey Lee
Hi,
Thank you for testing!
The EDK2 OVMF with adjusted PcdDxeNxMemoryProtectionPolicy
should work with the kernel itself.
As far as I can see from my testing with EDK2 OVMF, this
#PF occurred inside GRUB code before the first instruction
of the kernel. You can try using GRUB master branch, where
allocations are changed to use EfiLoaderCode type and with
PcdDxeNxMemoryProtectionPolicy=0x0000004 it will still be
executable.
Thanks,
Evgeniy Baskov
On Sun, Nov 20, 2022 at 06:37:40PM +0300, Evgeniy Baskov wrote:
> On 2022-11-20 04:49, joeyli wrote:
> > Hi Evgeniy,
> >
> > Thanks for your effort!
> >
> > On Tue, Oct 25, 2022 at 05:12:38PM +0300, Evgeniy Baskov wrote:
> ...
> >
> > Because Peter Jones point out this patchset to me, so I tried it
> > on OVMF, and I set the EfiLoaderData in DXE memory protection policy:
> >
> > Index: edk2/MdeModulePkg/MdeModulePkg.dec
> > ===================================================================
> > --- edk2.orig/MdeModulePkg/MdeModulePkg.dec
> > +++ edk2/MdeModulePkg/MdeModulePkg.dec
> > @@ -1392,7 +1392,7 @@
> > # e.g. 0x7BD4 can be used for all memory except Code and
> > ACPINVS/Reserved. <BR>
> > #
> > # @Prompt Set DXE memory protection policy.
> > -
> > gEfiMdeModulePkgTokenSpaceGuid.PcdDxeNxMemoryProtectionPolicy|0x0000000|UINT64|0x00001048^M
> > +
> > gEfiMdeModulePkgTokenSpaceGuid.PcdDxeNxMemoryProtectionPolicy|0x0000004|UINT64|0x00001048^M
> >
> > ## PCI Serial Device Info. It is an array of Device, Function, and
> > Power Management
> > # information that describes the path that contains zero or more
> > PCI to PCI bridges
> >
> >
> > I applied this v2 patch set on top of v6.1-rc5 kernel, and boot with a
> > shim which
> > set the PE NX-compatibility DLL Characteristic flag. I got a page
> > fault exception:
> >
> > Loading Linux 6.1.0-rc5-default+ ...
> > Loading initial ramdisk ...
> > !!!! X64 Exception Type - 0E(#PF - Page-Fault) CPU Apic ID - 00000000
> > !!!!
> > ExceptionData - 0000000000000011 I:1 R:0 U:0 W:0 P:1 PK:0 SS:0 SGX:0
> > RIP - 0000000076A3C390, CS - 0000000000000038, RFLAGS -
> > 0000000000210202
> > RAX - 000000007D8CCDF8, RCX - 0000000076A3C390, RDX - 000000007DE86000
> > RBX - 0000000076A3C000, RSP - 000000007FF0D2C8, RBP - 000000007DE86000
> > RSI - 000000007F9EE018, RDI - 000000007DFD1C18
> > R8 - 0000000076A3C000, R9 - 0000000000000190, R10 - 000000007FF1D658
> > R11 - 0000000000000004, R12 - 0000000000000190, R13 - 000000007D8CCE00
> > R14 - 000000007D8C76B4, R15 - 000000007BF0CBD5
> > DS - 0000000000000030, ES - 0000000000000030, FS - 0000000000000030
> > GS - 0000000000000030, SS - 0000000000000030
> > CR0 - 0000000080010033, CR2 - 0000000076A3C390, CR3 - 000000007FC01000
> > CR4 - 0000000000000668, CR8 - 0000000000000000
> > DR0 - 0000000000000000, DR1 - 0000000000000000, DR2 - 0000000000000000
> > DR3 - 0000000000000000, DR6 - 00000000FFFF0FF0, DR7 - 0000000000000400
> > GDTR - 000000007F9DE000 0000000000000047, LDTR - 0000000000000000
> > IDTR - 000000007F2E9018 0000000000000FFF, TR - 0000000000000000
> > FXSAVE_STATE - 000000007FF0CF20
> > !!!! Find image based on IP(0x7BF0BAB5)
> > /mnt/working/source_code-git/edk2/Build/OvmfX64/DEBUG_GCC5/X64/MdeModulePkg/Universal/Variable/RuntimeDxe/VariableRuntimeDxe/DEBUG/VariableRuntimeDxe.dll
> > (ImageBase=0000000000F40E7C, EntryPoint=0000000000F767B8) !!!!
> >
> >
> > My question is: Can I just set EfiLoaderData in DXE memory protection
> > policy
> > in EDK2/OVMF to test this patchset? Or which platform (virtual or
> > physical)
> > can we use for testing?
> >
> > Thanks a lot!
> > Joey Lee
>
> Hi,
>
> Thank you for testing!
>
> The EDK2 OVMF with adjusted PcdDxeNxMemoryProtectionPolicy
> should work with the kernel itself.
>
Thanks for your information. And yes, I have tested v6.1
kernel with this patch set success by direct booting EFI but
by firmware's EFI boot manager
> As far as I can see from my testing with EDK2 OVMF, this
> #PF occurred inside GRUB code before the first instruction
> of the kernel. You can try using GRUB master branch, where
> allocations are changed to use EfiLoaderCode type and with
> PcdDxeNxMemoryProtectionPolicy=0x0000004 it will still be
> executable.
>
Thanks! We will check new grub2!
Joey Lee