This is a note to let you know that I've just added the patch titled
jfs: UBSAN: shift-out-of-bounds in dbFindBits
to the 4.19-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
jfs-ubsan-shift-out-of-bounds-in-dbfindbits.patch
and it can be found in the queue-4.19 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
commit e875c75f9bd82e521a5970ecde8465f8a1f15179
Author: Remington Brasga <rbrasga@xxxxxxx>
Date: Wed Jul 10 00:12:44 2024 +0000
jfs: UBSAN: shift-out-of-bounds in dbFindBits
[ Upstream commit b0b2fc815e514221f01384f39fbfbff65d897e1c ]
Fix issue with UBSAN throwing shift-out-of-bounds warning.
Reported-by: syzbot+e38d703eeb410b17b473@xxxxxxxxxxxxxxxxxxxxxxxxx
Signed-off-by: Remington Brasga <rbrasga@xxxxxxx>
Signed-off-by: Dave Kleikamp <dave.kleikamp@xxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
diff --git a/fs/jfs/jfs_dmap.c b/fs/jfs/jfs_dmap.c
index 1128bcdf5024a..9f731847ae634 100644
--- a/fs/jfs/jfs_dmap.c
+++ b/fs/jfs/jfs_dmap.c
@@ -3097,7 +3097,7 @@ static int dbFindBits(u32 word, int l2nb)
/* scan the word for nb free bits at nb alignments.
*/
- for (bitno = 0; mask != 0; bitno += nb, mask >>= nb) {
+ for (bitno = 0; mask != 0; bitno += nb, mask = (mask >> nb)) {
if ((mask & word) == mask)
break;
}
