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Date:      Wed, 15 Oct 2025 20:20:09 GMT
From:      Mark Johnston <markj@FreeBSD.org>
To:        src-committers@FreeBSD.org, dev-commits-src-all@FreeBSD.org, dev-commits-src-main@FreeBSD.org
Subject:   git: c86af2cc4cd1 - main - imgact_elf: Check note body sizes
Message-ID:  <202510152020.59FKK9t2031314@gitrepo.freebsd.org>

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The branch main has been updated by markj:

URL: https://cgit.FreeBSD.org/src/commit/?id=c86af2cc4cd12fb0174843b22d737c3b5b5d55d0

commit c86af2cc4cd12fb0174843b22d737c3b5b5d55d0
Author:     Mark Johnston <markj@FreeBSD.org>
AuthorDate: 2025-10-15 20:14:36 +0000
Commit:     Mark Johnston <markj@FreeBSD.org>
CommitDate: 2025-10-15 20:14:36 +0000

    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 <ivansprundel@ioactive.com>
    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 c53707a1286c..a1fabbc86f27 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))



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