diff options
| author | Stanislav Fort <stanislav.fort@aisle.com> | 2025-09-02 14:00:49 +0300 |
|---|---|---|
| committer | Paul Moore <paul@paul-moore.com> | 2025-09-03 16:46:23 -0400 |
| commit | 4540f1d23e7f387880ce46d11b5cd3f27248bf8d (patch) | |
| tree | bf40d2a26ae286a0198beeaec5aa78e4b03f8af8 | |
| parent | 8f5ae30d69d7543eee0d70083daf4de8fe15d585 (diff) | |
audit: fix out-of-bounds read in audit_compare_dname_path()
When a watch on dir=/ is combined with an fsnotify event for a
single-character name directly under / (e.g., creating /a), an
out-of-bounds read can occur in audit_compare_dname_path().
The helper parent_len() returns 1 for "/". In audit_compare_dname_path(),
when parentlen equals the full path length (1), the code sets p = path + 1
and pathlen = 1 - 1 = 0. The subsequent loop then dereferences
p[pathlen - 1] (i.e., p[-1]), causing an out-of-bounds read.
Fix this by adding a pathlen > 0 check to the while loop condition
to prevent the out-of-bounds access.
Cc: stable@vger.kernel.org
Fixes: e92eebb0d611 ("audit: fix suffixed '/' filename matching")
Reported-by: Stanislav Fort <disclosure@aisle.com>
Suggested-by: Linus Torvalds <torvalds@linuxfoundation.org>
Signed-off-by: Stanislav Fort <stanislav.fort@aisle.com>
[PM: subject tweak, sign-off email fixes]
Signed-off-by: Paul Moore <paul@paul-moore.com>
| -rw-r--r-- | kernel/auditfilter.c | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/kernel/auditfilter.c b/kernel/auditfilter.c index e3f42018ed46..f7708fe2c457 100644 --- a/kernel/auditfilter.c +++ b/kernel/auditfilter.c @@ -1326,7 +1326,7 @@ int audit_compare_dname_path(const struct qstr *dname, const char *path, int par /* handle trailing slashes */ pathlen -= parentlen; - while (p[pathlen - 1] == '/') + while (pathlen > 0 && p[pathlen - 1] == '/') pathlen--; if (pathlen != dlen) |