From cbab7f726877badc5059316e7248be7c3bff9d96 Mon Sep 17 00:00:00 2001 From: Aurelien Jarno Date: Sun, 5 Dec 2021 11:51:17 +0100 Subject: localedef: check magic value on archive load [BZ #28650] localedef currently blindly trust the archive header. When passed an archive file with the wrong endianess, this leads to a segmentation fault: $ localedef --big-endian --list-archive /usr/lib/locale/locale-archive Segmentation fault (core dumped) When passed non-archive files, asserts are reported on the best case, but sometimes it can lead to a segmentation fault: $ localedef --list-archive /bin/true localedef: programs/locarchive.c:1643: show_archive_content: Assertion `used < GET (head->namehash_used)' failed. Aborted (core dumped) $ localedef --list-archive /usr/lib/locale/C.utf8/LC_COLLATE Segmentation fault (core dumped) This patch improves the user experience by looking at the magic value, which is always written, but never checked. It should still be possible to trigger a segmentation fault with crafted files, but this already catch many cases. --- locale/programs/locarchive.c | 7 +++++++ 1 file changed, 7 insertions(+) (limited to 'locale/programs') diff --git a/locale/programs/locarchive.c b/locale/programs/locarchive.c index eeec3ab648..477499bd40 100644 --- a/locale/programs/locarchive.c +++ b/locale/programs/locarchive.c @@ -654,6 +654,13 @@ open_archive (struct locarhandle *ah, bool readonly) error (EXIT_FAILURE, errno, _("cannot read archive header")); } + /* Check the magic value */ + if (GET (head.magic) != AR_MAGIC) + { + (void) lockf64 (fd, F_ULOCK, sizeof (struct locarhead)); + error (EXIT_FAILURE, 0, _("bad magic value in archive header")); + } + ah->fd = fd; ah->mmaped = st.st_size; -- cgit v1.2.3