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)
committerDavid Sterba <dsterba@suse.com>
Tue, 11 Apr 2017 16:49:56 +0000 (18:49 +0200)
commita967efb30b3afa3d858edd6a17f544f9e9e46eea
tree86b2f9e56b32934fc56b46148feb8509cf72c81b
parent97bf5a5589aa3a59c60aa775fc12ec0483fc5002
Btrfs: fix potential use-after-free for cloned bio

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>
fs/btrfs/volumes.c