tree 98dd50e4b0420724c04fe00b188155fcb41a4476
parent 3d84fa98aca7f05f7010022bc45acb1b50326332
author Michael S. Tsirkin <mst@redhat.com> 1363488369 +0000
committer David S. Miller <davem@davemloft.net> 1363544934 -0400

vhost/net: fix heads usage of ubuf_info

ubuf info allocator uses guest controlled head as an index,
so a malicious guest could put the same head entry in the ring twice,
and we will get two callbacks on the same value.
To fix use upend_idx which is guaranteed to be unique.

Reported-by: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Cc: stable@kernel.org
Signed-off-by: David S. Miller <davem@davemloft.net>