kernel/net-vhost-validate-vhost_get_vq_desc-return-value.patch

56 lines
1.6 KiB
Diff
Raw Normal View History

Bugzilla: 1081503
Upstream-status: Sent to netdev
From patchwork Thu Mar 27 10:53:37 2014
Content-Type: text/plain; charset="utf-8"
MIME-Version: 1.0
Content-Transfer-Encoding: 7bit
Subject: [net] vhost: validate vhost_get_vq_desc return value
From: "Michael S. Tsirkin" <mst@redhat.com>
X-Patchwork-Id: 334291
Message-Id: <1395917517-30937-1-git-send-email-mst@redhat.com>
To: linux-kernel@vger.kernel.org
Cc: kvm@vger.kernel.org, virtio-dev@lists.oasis-open.org,
virtualization@lists.linux-foundation.org, netdev@vger.kernel.org,
David Miller <davem@davemloft.net>, Jason Wang <jasowang@redhat.com>
Date: Thu, 27 Mar 2014 12:53:37 +0200
vhost fails to validate negative error code
from vhost_get_vq_desc causing
a crash: we are using -EFAULT which is 0xfffffff2
as vector size, which exceeds the allocated size.
The code in question was introduced in commit
8dd014adfea6f173c1ef6378f7e5e7924866c923
vhost-net: mergeable buffers support
CVE-2014-0055
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
---
This is needed in -stable.
drivers/vhost/net.c | 6 +++++-
1 file changed, 5 insertions(+), 1 deletion(-)
diff --git a/drivers/vhost/net.c b/drivers/vhost/net.c
index 026be58..e1e22e0 100644
--- a/drivers/vhost/net.c
+++ b/drivers/vhost/net.c
@@ -505,9 +505,13 @@ static int get_rx_bufs(struct vhost_virtqueue *vq,
r = -ENOBUFS;
goto err;
}
- d = vhost_get_vq_desc(vq->dev, vq, vq->iov + seg,
+ r = vhost_get_vq_desc(vq->dev, vq, vq->iov + seg,
ARRAY_SIZE(vq->iov) - seg, &out,
&in, log, log_num);
+ if (unlikely(r < 0))
+ goto err;
+
+ d = r;
if (d == vq->num) {
r = 0;
goto err;