This is a note to let you know that I've just added the patch titled
x86/boot: Construct PE/COFF .text section from assembler
to the 6.6-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
x86-boot-construct-pe-coff-.text-section-from-assembler.patch
and it can be found in the queue-6.6 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
>From efa089e63b56bdc5eca754b995cb039dd7a5457e Mon Sep 17 00:00:00 2001
From: Ard Biesheuvel <ardb@xxxxxxxxxx>
Date: Fri, 15 Sep 2023 17:16:29 +0000
Subject: x86/boot: Construct PE/COFF .text section from assembler
From: Ard Biesheuvel <ardb@xxxxxxxxxx>
commit efa089e63b56bdc5eca754b995cb039dd7a5457e upstream.
Now that the size of the setup block is visible to the assembler, it is
possible to populate the PE/COFF header fields from the asm code
directly, instead of poking the values into the binary using the build
tool. This will make it easier to reorganize the section layout without
having to tweak the build tool in lockstep.
This change has no impact on the resulting bzImage binary.
Signed-off-by: Ard Biesheuvel <ardb@xxxxxxxxxx>
Signed-off-by: Ingo Molnar <mingo@xxxxxxxxxx>
Link: https://lore.kernel.org/r/20230915171623.655440-15-ardb@xxxxxxxxxx
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
arch/x86/boot/header.S | 22 ++++++--------------
arch/x86/boot/tools/build.c | 47 --------------------------------------------
2 files changed, 7 insertions(+), 62 deletions(-)
--- a/arch/x86/boot/header.S
+++ b/arch/x86/boot/header.S
@@ -75,14 +75,12 @@ optional_header:
.byte 0x02 # MajorLinkerVersion
.byte 0x14 # MinorLinkerVersion
- # Filled in by build.c
- .long 0 # SizeOfCode
+ .long setup_size + ZO__end - 0x200 # SizeOfCode
.long 0 # SizeOfInitializedData
.long 0 # SizeOfUninitializedData
- # Filled in by build.c
- .long 0x0000 # AddressOfEntryPoint
+ .long setup_size + ZO_efi_pe_entry # AddressOfEntryPoint
.long 0x0200 # BaseOfCode
#ifdef CONFIG_X86_32
@@ -105,10 +103,7 @@ extra_header_fields:
.word 0 # MinorSubsystemVersion
.long 0 # Win32VersionValue
- #
- # The size of the bzImage is written in tools/build.c
- #
- .long 0 # SizeOfImage
+ .long setup_size + ZO__end # SizeOfImage
.long 0x200 # SizeOfHeaders
.long 0 # CheckSum
@@ -199,18 +194,15 @@ section_table:
IMAGE_SCN_MEM_DISCARDABLE # Characteristics
#endif
- #
- # 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
+ .long ZO__end
+ .long setup_size
+ .long ZO__edata # Size of initialized data
# on disk
- .long 0x0 # startup_{32,64}
+ .long setup_size
.long 0 # PointerToRelocations
.long 0 # PointerToLineNumbers
.word 0 # NumberOfRelocations
--- a/arch/x86/boot/tools/build.c
+++ b/arch/x86/boot/tools/build.c
@@ -50,10 +50,8 @@ u8 buf[SETUP_SECT_MAX*512];
#define PECOFF_RELOC_RESERVE 0x20
#define PECOFF_COMPAT_RESERVE 0x20
-static unsigned long efi_pe_entry;
static unsigned long efi32_pe_entry;
static unsigned long _edata;
-static unsigned long _end;
/*----------------------------------------------------------------------*/
@@ -216,32 +214,6 @@ static void update_pecoff_setup_and_relo
#endif
}
-static void update_pecoff_text(unsigned int text_start, unsigned int file_sz)
-{
- unsigned int pe_header;
- unsigned int text_sz = file_sz - text_start;
- unsigned int bss_sz = _end - text_sz;
-
- pe_header = get_unaligned_le32(&buf[0x3c]);
-
- /*
- * 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]);
-
- /* Size of image */
- put_unaligned_le32(file_sz + bss_sz, &buf[pe_header + 0x50]);
-
- /*
- * Address of entry point for PE/COFF executable
- */
- put_unaligned_le32(text_start + efi_pe_entry, &buf[pe_header + 0x28]);
-
- update_pecoff_section_header_fields(".text", text_start, text_sz + bss_sz,
- text_sz, text_start);
-}
-
static int reserve_pecoff_reloc_section(int c)
{
/* Reserve 0x20 bytes for .reloc section */
@@ -249,22 +221,9 @@ static int reserve_pecoff_reloc_section(
return PECOFF_RELOC_RESERVE;
}
-static void efi_stub_defaults(void)
-{
- /* Defaults for old kernel */
-#ifdef CONFIG_X86_32
- efi_pe_entry = 0x10;
-#else
- efi_pe_entry = 0x210;
-#endif
-}
-
#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) {}
-static inline void efi_stub_defaults(void) {}
static inline int reserve_pecoff_reloc_section(int c)
{
@@ -307,10 +266,8 @@ static void parse_zoffset(char *fname)
p = (char *)buf;
while (p && *p) {
- PARSE_ZOFS(p, efi_pe_entry);
PARSE_ZOFS(p, efi32_pe_entry);
PARSE_ZOFS(p, _edata);
- PARSE_ZOFS(p, _end);
p = strchr(p, '\n');
while (p && (*p == '\r' || *p == '\n'))
@@ -328,8 +285,6 @@ int main(int argc, char ** argv)
void *kernel;
u32 crc = 0xffffffffUL;
- efi_stub_defaults();
-
if (argc != 5)
usage();
parse_zoffset(argv[3]);
@@ -376,8 +331,6 @@ int main(int argc, char ** argv)
kernel = mmap(NULL, sz, PROT_READ, MAP_SHARED, fd, 0);
if (kernel == MAP_FAILED)
die("Unable to mmap '%s': %m", argv[2]);
- update_pecoff_text(setup_sectors * 512, i + _edata);
-
crc = partial_crc32(buf, i, crc);
if (fwrite(buf, 1, i, dest) != i)
Patches currently in stable-queue which might be from ardb@xxxxxxxxxx are
queue-6.6/x86-boot-increase-section-and-file-alignment-to-4k-512.patch
queue-6.6/x86-boot-derive-file-size-from-_edata-symbol.patch
queue-6.6/x86-boot-construct-pe-coff-.text-section-from-assembler.patch
queue-6.6/x86-boot-split-off-pe-coff-.data-section.patch
queue-6.6/kallsyms-ignore-armv4-thunks-along-with-others.patch
queue-6.6/x86-efi-drop-alignment-flags-from-pe-section-headers.patch
queue-6.6/x86-boot-drop-references-to-startup_64.patch
queue-6.6/x86-efistub-use-1-1-file-memory-mapping-for-pe-coff-.compat-section.patch
queue-6.6/x86-boot-drop-pe-coff-.reloc-section.patch
queue-6.6/x86-boot-set-efi-handover-offset-directly-in-header-asm.patch
queue-6.6/x86-efi-drop-efi-stub-.bss-from-.data-section.patch
queue-6.6/x86-efi-disregard-setup-header-of-loaded-image.patch
queue-6.6/x86-boot-grab-kernel_info-offset-from-zoffset-header-directly.patch
queue-6.6/x86-boot-drop-redundant-code-setting-the-root-device.patch
queue-6.6/x86-boot-remove-the-bugger-off-message.patch
queue-6.6/x86-boot-omit-compression-buffer-from-pe-coff-image-memory-footprint.patch
queue-6.6/x86-boot-define-setup-size-in-linker-script.patch
