5.4-stable review patch. If anyone has any objections, please let me know.
------------------
From: Vasiliy Kovalev kovalev@altlinux.org
[ Upstream commit a406aff8c05115119127c962cbbbbd202e1973ef ]
The l_tree_depth field is 16-bit (__le16), but the actual maximum depth is limited to OCFS2_MAX_PATH_DEPTH.
Add a check to prevent out-of-bounds access if l_tree_depth has an invalid value, which may occur when reading from a corrupted mounted disk [1].
Link: https://lkml.kernel.org/r/20250214084908.736528-1-kovalev@altlinux.org Fixes: ccd979bdbce9 ("[PATCH] OCFS2: The Second Oracle Cluster Filesystem") Signed-off-by: Vasiliy Kovalev kovalev@altlinux.org Reported-by: syzbot+66c146268dc88f4341fd@syzkaller.appspotmail.com Closes: https://syzkaller.appspot.com/bug?extid=66c146268dc88f4341fd [1] Reviewed-by: Joseph Qi joseph.qi@linux.alibaba.com Cc: Joel Becker jlbec@evilplan.org Cc: Junxiao Bi junxiao.bi@oracle.com Cc: Changwei Ge gechangwei@live.cn Cc: Jun Piao piaojun@huawei.com Cc: Kurt Hackel kurt.hackel@oracle.com Cc: Mark Fasheh mark@fasheh.com Cc: Vasiliy Kovalev kovalev@altlinux.org Signed-off-by: Andrew Morton akpm@linux-foundation.org Signed-off-by: Sasha Levin sashal@kernel.org --- fs/ocfs2/alloc.c | 8 ++++++++ 1 file changed, 8 insertions(+)
diff --git a/fs/ocfs2/alloc.c b/fs/ocfs2/alloc.c index 52ccd8d4ed820..0d2dbf3fded2a 100644 --- a/fs/ocfs2/alloc.c +++ b/fs/ocfs2/alloc.c @@ -1799,6 +1799,14 @@ static int __ocfs2_find_path(struct ocfs2_caching_info *ci,
el = root_el; while (el->l_tree_depth) { + if (unlikely(le16_to_cpu(el->l_tree_depth) >= OCFS2_MAX_PATH_DEPTH)) { + ocfs2_error(ocfs2_metadata_cache_get_super(ci), + "Owner %llu has invalid tree depth %u in extent list\n", + (unsigned long long)ocfs2_metadata_cache_owner(ci), + le16_to_cpu(el->l_tree_depth)); + ret = -EROFS; + goto out; + } if (le16_to_cpu(el->l_next_free_rec) == 0) { ocfs2_error(ocfs2_metadata_cache_get_super(ci), "Owner %llu has empty extent list at depth %u\n",