tree af8ac48b434b15fa4efa6dead7ea2c037d03fc99
parent 1e5ec2e709bd8c5588fdbdda909945e4e2be8d23
author Jeff Mahoney <jeffm@suse.com> 1474461089 -0400
committer Chris Mason <clm@fb.com> 1474503736 -0700

btrfs: ensure that file descriptor used with subvol ioctls is a dir

If the subvol/snapshot create/destroy ioctls are passed a regular file
with execute permissions set, we'll eventually Oops while trying to do
inode->i_op->lookup via lookup_one_len.

This patch ensures that the file descriptor refers to a directory.

Fixes: cb8e70901d (Btrfs: Fix subvolume creation locking rules)
Fixes: 76dda93c6a (Btrfs: add snapshot/subvolume destroy ioctl)
Cc: <stable@vger.kernel.org> #v2.6.29+
Signed-off-by: Jeff Mahoney <jeffm@suse.com>
Signed-off-by: Chris Mason <clm@fb.com>