]> git.hungrycats.org Git - linux/commit
vhost/net: fix heads usage of ubuf_info
authorMichael S. Tsirkin <mst@redhat.com>
Sun, 17 Mar 2013 02:46:09 +0000 (02:46 +0000)
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Thu, 28 Mar 2013 19:17:21 +0000 (12:17 -0700)
commit82ad1a1163aae6fb9a0bb0d370a81a8d919ff7b5
tree169a94de70eed08fc7ab0a0728bf75867f99a95a
parent0bf2c46258b0ace08dc5e27b732d24606adc3b2e
vhost/net: fix heads usage of ubuf_info

[ Upstream commit 46aa92d1ba162b4b3d6b7102440e459d4e4ee255 ]

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>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
drivers/vhost/net.c