[PATCH AUTOSEL 5.10 21/33] jfs: fix shift-out-of-bounds in dbSplit

Sasha Levin
2024-11-24T13:54:53Z

From: Ghanshyam Agrawal <ghanshyam1898@gmail.com>

[ Upstream commit a5f5e4698f8abbb25fe4959814093fb5bfa1aa9d ]

When dmt_budmin is less than zero, it causes errors
in the later stages. Added a check to return an error beforehand
in dbAllocCtl itself.

Reported-by: syzbot+b5ca8a249162c4b9a7d0@syzkaller.appspotmail.com
Closes: https://syzkaller.appspot.com/bug?extid=b5ca8a249162c4b9a7d0
Signed-off-by: Ghanshyam Agrawal <ghanshyam1898@gmail.com>
Signed-off-by: Dave Kleikamp <dave.kleikamp@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
fs/jfs/jfs_dmap.c | 3 +++
1 file changed, 3 insertions(+)

diff --git a/fs/jfs/jfs_dmap.c b/fs/jfs/jfs_dmap.c
index 559f6ebebfc0c..c61fcf0e88d29 100644
--- a/fs/jfs/jfs_dmap.c
+++ b/fs/jfs/jfs_dmap.c
@@ -1886,6 +1886,9 @@ dbAllocCtl(struct bmap * bmp, s64 nblocks, int l2nb, s64 blkno, s64 * results)
return -EIO;
dp = (struct dmap *) mp->data;

+ if (dp->tree.budmin < 0)
+ return -EIO;
+
/* try to allocate the blocks.
*/
rc = dbAllocDmapLev(bmp, dp, (int) nblocks, l2nb, results);
--
2.43.0