Btrfs: fix potential use-after-free for cloned bio
authorLiu Bo <bo.li.liu@oracle.com>
Mon, 10 Apr 2017 19:36:26 +0000 (12:36 -0700)
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Sun, 8 Oct 2017 08:26:08 +0000 (10:26 +0200)
commit26899ca9cc6fc5e29c1f489d76a246bcad745f2d
tree6701ac3fad51a7c7ac9e97c80ada14a902ddbbf0
parentc17acd24c682322563c9c35bd7ed94f13fed3664
Btrfs: fix potential use-after-free for cloned bio

[ Upstream commit a967efb30b3afa3d858edd6a17f544f9e9e46eea ]

KASAN reports that there is a use-after-free case of bio in btrfs_map_bio.

If we need to submit IOs to several disks at a time, the original bio
would get cloned and mapped to the destination disk, but we really should
use the original bio instead of a cloned bio to do the sanity check
because cloned bios are likely to be freed by its endio.

Reported-by: Diego <diegocg@gmail.com>
Signed-off-by: Liu Bo <bo.li.liu@oracle.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Sasha Levin <alexander.levin@verizon.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
fs/btrfs/volumes.c