jfs: validate max amount of blocks before allocation.
authorAlexei Filippov <halip0503@gmail.com>
Sat, 19 Aug 2023 17:32:16 +0000 (20:32 +0300)
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Wed, 13 Sep 2023 07:42:49 +0000 (09:42 +0200)
commitf27f759f4cd490593cc7527b03fcec3aa4dbc2e7
tree6577dacdc0486574cea75b885dabd7924c01b9a8
parentb648f57175815919d2ccd1b152ba1d03a8886598
jfs: validate max amount of blocks before allocation.

[ Upstream commit 0225e10972fa809728b8d4c1bd2772b3ec3fdb57 ]

The lack of checking bmp->db_max_freebud in extBalloc() can lead to
shift out of bounds, so this patch prevents undefined behavior, because
bmp->db_max_freebud == -1 only if there is no free space.

Signed-off-by: Aleksei Filippov <halip0503@gmail.com>
Signed-off-by: Dave Kleikamp <dave.kleikamp@oracle.com>
Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2")
Reported-and-tested-by: syzbot+5f088f29593e6b4c8db8@syzkaller.appspotmail.com
Closes: https://syzkaller.appspot.com/bug?id=01abadbd6ae6a08b1f1987aa61554c6b3ac19ff2
Signed-off-by: Sasha Levin <sashal@kernel.org>
fs/jfs/jfs_extent.c