From c86af2cc4cd12fb0174843b22d737c3b5b5d55d0 Mon Sep 17 00:00:00 2001 From: Mark Johnston Date: Wed, 15 Oct 2025 20:14:36 +0000 Subject: [PATCH] imgact_elf: Check note body sizes In parse_notes we validate that the note name fits within the note buffer, but we do not do the same for the note data, so there is some potential for an OOB read in the note handler. Add a bounds check. Reported by: Ilja Van Sprundel Reviewed by: kib, emaste MFC after: 1 week Differential Revision: https://reviews.freebsd.org/D53063 --- sys/kern/imgact_elf.c | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-) diff --git a/sys/kern/imgact_elf.c b/sys/kern/imgact_elf.c index c53707a1286..a1fabbc86f2 100644 --- a/sys/kern/imgact_elf.c +++ b/sys/kern/imgact_elf.c @@ -2831,7 +2831,7 @@ __elfN(parse_notes)(const struct image_params *imgp, const Elf_Note *checknote, } if ((const char *)note_end - (const char *)note < sizeof(Elf_Note)) { - uprintf("ELF note to short\n"); + uprintf("ELF note too short\n"); goto retf; } if (note->n_namesz != checknote->n_namesz || @@ -2839,9 +2839,9 @@ __elfN(parse_notes)(const struct image_params *imgp, const Elf_Note *checknote, note->n_type != checknote->n_type) goto nextnote; note_name = (const char *)(note + 1); - if (note_name + checknote->n_namesz >= - (const char *)note_end || strncmp(note_vendor, - note_name, checknote->n_namesz) != 0) + if (note_name + roundup2(note->n_namesz, ELF_NOTE_ROUNDSIZE) + + note->n_descsz >= (const char *)note_end || + strncmp(note_vendor, note_name, checknote->n_namesz) != 0) goto nextnote; if (cb(note, cb_arg, &res))