This is a note to let you know that I've just added the patch titled
jfs: fix shift-out-of-bounds in dbJoin
to the 6.6-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-fix-shift-out-of-bounds-in-dbjoin.patch
and it can be found in the queue-6.6 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
commit 1e5ac6522ac882c585a4b5ce686a455222a88561
Author: Manas Ghandat <ghandatmanas@xxxxxxxxx>
Date: Wed Oct 11 20:09:37 2023 +0530
jfs: fix shift-out-of-bounds in dbJoin
[ Upstream commit cca974daeb6c43ea971f8ceff5a7080d7d49ee30 ]
Currently while joining the leaf in a buddy system there is shift out
of bound error in calculation of BUDSIZE. Added the required check
to the BUDSIZE and fixed the documentation as well.
Reported-by: syzbot+411debe54d318eaed386@xxxxxxxxxxxxxxxxxxxxxxxxx
Closes: https://syzkaller.appspot.com/bug?extid=411debe54d318eaed386
Signed-off-by: Manas Ghandat <ghandatmanas@xxxxxxxxx>
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 cb3cda1390adb..8eec84c651bfb 100644
--- a/fs/jfs/jfs_dmap.c
+++ b/fs/jfs/jfs_dmap.c
@@ -2763,7 +2763,9 @@ static int dbBackSplit(dmtree_t *tp, int leafno, bool is_ctl)
* leafno - the number of the leaf to be updated.
* newval - the new value for the leaf.
*
- * RETURN VALUES: none
+ * RETURN VALUES:
+ * 0 - success
+ * -EIO - i/o error
*/
static int dbJoin(dmtree_t *tp, int leafno, int newval, bool is_ctl)
{
@@ -2790,6 +2792,10 @@ static int dbJoin(dmtree_t *tp, int leafno, int newval, bool is_ctl)
* get the buddy size (number of words covered) of
* the new value.
*/
+
+ if ((newval - tp->dmt_budmin) > BUDMIN)
+ return -EIO;
+
budsz = BUDSIZE(newval, tp->dmt_budmin);
/* try to join.
