From: Ghanshyam Agrawal <ghanshyam1898@xxxxxxxxx> [ 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> --- fs/jfs/jfs_dtree.c | 7 +++++++ 1 file changed, 7 insertions(+) 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 */ -- 2.43.0
