From 60592fb6b67c653beaa2e7acad9a9d7aa0b71dff Mon Sep 17 00:00:00 2001 From: Fangrui Song Date: Fri, 12 May 2023 02:25:28 +0000 Subject: 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 Signed-off-by: Kees Cook Link: https://lore.kernel.org/r/20230512022528.3430327-1-maskray@google.com --- fs/proc/vmcore.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) (limited to 'fs/proc') 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); -- cgit v1.2.3