diff options
| author | Fangrui Song <maskray@google.com> | 2023-05-12 02:25:28 +0000 |
|---|---|---|
| committer | Kees Cook <keescook@chromium.org> | 2023-05-16 14:32:00 -0700 |
| commit | 60592fb6b67c653beaa2e7acad9a9d7aa0b71dff (patch) | |
| tree | 27f14ecfcbf21dd70c09f2b27764a0c38a1eacd0 | |
| parent | f1fcbaa18b28dec10281551dfe6ed3a3ed80e3d6 (diff) | |
| download | linux-next-60592fb6b67c653beaa2e7acad9a9d7aa0b71dff.tar.gz | |
coredump, vmcore: Set p_align to 4 for PT_NOTE
Tools like readelf/llvm-readelf use p_align to parse a PT_NOTE program
header as an array of 4-byte entries or 8-byte entries. Currently, there
are workarounds[1] in place for Linux to treat p_align==0 as 4. However,
it would be more appropriate to set the correct alignment so that tools
do not have to rely on guesswork. FreeBSD coredumps set p_align to 4 as
well.
[1]: https://sourceware.org/git/?p=binutils-gdb.git;a=commit;h=82ed9683ec099d8205dc499ac84febc975235af6
[2]: https://reviews.llvm.org/D150022
Signed-off-by: Fangrui Song <maskray@google.com>
Signed-off-by: Kees Cook <keescook@chromium.org>
Link: https://lore.kernel.org/r/20230512022528.3430327-1-maskray@google.com
| -rw-r--r-- | fs/binfmt_elf.c | 2 | ||||
| -rw-r--r-- | fs/binfmt_elf_fdpic.c | 2 | ||||
| -rw-r--r-- | fs/proc/vmcore.c | 4 |
3 files changed, 4 insertions, 4 deletions
diff --git a/fs/binfmt_elf.c b/fs/binfmt_elf.c index 1033fbdfdbec..44b4c42ab8e8 100644 --- a/fs/binfmt_elf.c +++ b/fs/binfmt_elf.c @@ -1517,7 +1517,7 @@ static void fill_elf_note_phdr(struct elf_phdr *phdr, int sz, loff_t offset) phdr->p_filesz = sz; phdr->p_memsz = 0; phdr->p_flags = 0; - phdr->p_align = 0; + phdr->p_align = 4; } static void fill_note(struct memelfnote *note, const char *name, int type, diff --git a/fs/binfmt_elf_fdpic.c b/fs/binfmt_elf_fdpic.c index 05a1471d5283..d76ad3d4f676 100644 --- a/fs/binfmt_elf_fdpic.c +++ b/fs/binfmt_elf_fdpic.c @@ -1269,7 +1269,7 @@ static inline void fill_elf_note_phdr(struct elf_phdr *phdr, int sz, loff_t offs phdr->p_filesz = sz; phdr->p_memsz = 0; phdr->p_flags = 0; - phdr->p_align = 0; + phdr->p_align = 4; return; } diff --git a/fs/proc/vmcore.c b/fs/proc/vmcore.c index 03f5963914a1..cb80a7703d58 100644 --- a/fs/proc/vmcore.c +++ b/fs/proc/vmcore.c @@ -877,7 +877,7 @@ static int __init merge_note_headers_elf64(char *elfptr, size_t *elfsz, phdr.p_offset = roundup(note_off, PAGE_SIZE); phdr.p_vaddr = phdr.p_paddr = 0; phdr.p_filesz = phdr.p_memsz = phdr_sz; - phdr.p_align = 0; + phdr.p_align = 4; /* Add merged PT_NOTE program header*/ tmp = elfptr + sizeof(Elf64_Ehdr); @@ -1068,7 +1068,7 @@ static int __init merge_note_headers_elf32(char *elfptr, size_t *elfsz, phdr.p_offset = roundup(note_off, PAGE_SIZE); phdr.p_vaddr = phdr.p_paddr = 0; phdr.p_filesz = phdr.p_memsz = phdr_sz; - phdr.p_align = 0; + phdr.p_align = 4; /* Add merged PT_NOTE program header*/ tmp = elfptr + sizeof(Elf32_Ehdr); |