This is a note to let you know that I've just added the patch titled
jfs: array-index-out-of-bounds fix in dtReadFirst
to the 5.4-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-array-index-out-of-bounds-fix-in-dtreadfirst.patch
and it can be found in the queue-5.4 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
commit a76b00e0c55302197c1759191d2962f3ff1eb2d5
Author: Ghanshyam Agrawal <ghanshyam1898@xxxxxxxxx>
Date: Sat Sep 28 14:07:22 2024 +0530
jfs: array-index-out-of-bounds fix in dtReadFirst
[ Upstream commit ca84a2c9be482836b86d780244f0357e5a778c46 ]
The value of stbl can be sometimes out of bounds due
to a bad filesystem. Added a check with appopriate return
of error code in that case.
Reported-by: syzbot+65fa06e29859e41a83f3@xxxxxxxxxxxxxxxxxxxxxxxxx
Closes: https://syzkaller.appspot.com/bug?extid=65fa06e29859e41a83f3
Signed-off-by: Ghanshyam Agrawal <ghanshyam1898@xxxxxxxxx>
Signed-off-by: Dave Kleikamp <dave.kleikamp@xxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
diff --git a/fs/jfs/jfs_dtree.c b/fs/jfs/jfs_dtree.c
index 077a87e530205..bd198b04c388f 100644
--- a/fs/jfs/jfs_dtree.c
+++ b/fs/jfs/jfs_dtree.c
@@ -3382,6 +3382,13 @@ static int dtReadFirst(struct inode *ip, struct btstack * btstack)
/* get the leftmost entry */
stbl = DT_GETSTBL(p);
+
+ if (stbl[0] < 0 || stbl[0] > 127) {
+ DT_PUTPAGE(mp);
+ jfs_error(ip->i_sb, "stbl[0] out of bound\n");
+ return -EIO;
+ }
+
xd = (pxd_t *) & p->slot[stbl[0]];
/* get the child page block address */
