5.4-stable review patch. If anyone has any objections, please let me know.
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From: Ghanshyam Agrawal ghanshyam1898@gmail.com
[ 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@syzkaller.appspotmail.com Closes: https://syzkaller.appspot.com/bug?extid=65fa06e29859e41a83f3 Signed-off-by: Ghanshyam Agrawal ghanshyam1898@gmail.com Signed-off-by: Dave Kleikamp dave.kleikamp@oracle.com Signed-off-by: Sasha Levin sashal@kernel.org --- 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 */