netdev - [PATCH net] vhost: validate vhost_get_vq

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [thread-next>] [day] [month] [year] [list]

Message-ID: <1395917517-30937-1-git-send-email-mst@redhat.com>
Date:	Thu, 27 Mar 2014 12:53:37 +0200
From:	"Michael S. Tsirkin" <mst@...hat.com>
To:	linux-kernel@...r.kernel.org
Cc:	kvm@...r.kernel.org, virtio-dev@...ts.oasis-open.org,
	virtualization@...ts.linux-foundation.org, netdev@...r.kernel.org,
	David Miller <davem@...emloft.net>,
	Jason Wang <jasowang@...hat.com>
Subject: [PATCH net] vhost: validate vhost_get_vq_desc return value

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@...hat.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;
-- 
MST
--
To unsubscribe from this list: send the line "unsubscribe netdev" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html