From: Remington Brasga <rbrasga@uci.edu>
Date: Wed, 10 Jul 2024 00:12:44 +0000 (+0000)
Subject: jfs: UBSAN: shift-out-of-bounds in dbFindBits
X-Git-Tag: v6.12-rc1~141^2~4
X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=b0b2fc815e514221f01384f39fbfbff65d897e1c;p=thirdparty%2Fkernel%2Flinux.git

jfs: UBSAN: shift-out-of-bounds in dbFindBits

Fix issue with UBSAN throwing shift-out-of-bounds warning.

Reported-by: syzbot+e38d703eeb410b17b473@syzkaller.appspotmail.com
Signed-off-by: Remington Brasga <rbrasga@uci.edu>
Signed-off-by: Dave Kleikamp <dave.kleikamp@oracle.com>
---

diff --git a/fs/jfs/jfs_dmap.c b/fs/jfs/jfs_dmap.c
index 5713994328cbc..ccdfa38d7a682 100644
--- a/fs/jfs/jfs_dmap.c
+++ b/fs/jfs/jfs_dmap.c
@@ -3022,7 +3022,7 @@ 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;
 	}