Re: [syzbot] [jfs?] UBSAN: array-index-out-of-bounds in diFree

[Jeongjun Park <aha310510@gmail.com>]

please test array-index-out-of-bounds in diFree

#syz test git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/ master

---
 fs/jfs/jfs_imap.c | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/fs/jfs/jfs_imap.c b/fs/jfs/jfs_imap.c
index 2ec35889ad24..977751b30489 100644
--- a/fs/jfs/jfs_imap.c
+++ b/fs/jfs/jfs_imap.c
@@ -881,6 +881,11 @@ int diFree(struct inode *ip)
 	 */
 	agno = BLKTOAG(JFS_IP(ip)->agstart, JFS_SBI(ip->i_sb));
 
+	if(agno >= MAXAG){
+		jfs_error(ip->i_sb, "invalid array index (agno >= MAXAG), agno = %d\n", agno);
+		return -ENOMEM;
+	}
+
 	/* Lock the AG specific inode map information
 	 */
 	AG_LOCK(imap, agno);
-- 
2.34.1