DPDK patches and discussions
 help / color / mirror / Atom feed
* [dpdk-dev] [PATCH v2] vhost: fix vring message handling broken in some case
@ 2019-11-13 11:03 Zhike Wang
  2019-11-14  8:52 ` Maxime Coquelin
  0 siblings, 1 reply; 7+ messages in thread
From: Zhike Wang @ 2019-11-13 11:03 UTC (permalink / raw)
  To: dev, stable, security; +Cc: wangzhike, Zhike Wang

When VHOST_USER_VRING_NOFD_MASK is set, the fd_num is 0,
so validate_msg_fds() will return error. In this case,
the negotiation of vring message between vhost user front end and
back end would fail, and as a result, vhost user link could NOT be up.

How to reproduce:
1.Run dpdk testpmd insides VM, which locates at host with ovs+dpdk.
2.Notice that inside ovs there are endless logs regarding failure to
handle VHOST_USER_SET_VRING_CALL, and link of vm could NOT be up.

Fixes: bf47225 ("vhost: fix possible denial of service by leaking FDs")
Signed-off-by: Zhike Wang <wangzk320@163.com>
---
 lib/librte_vhost/vhost_user.c | 13 ++++++++++---
 1 file changed, 10 insertions(+), 3 deletions(-)

diff --git a/lib/librte_vhost/vhost_user.c b/lib/librte_vhost/vhost_user.c
index 90ecee1..0cfb8b7 100644
--- a/lib/librte_vhost/vhost_user.c
+++ b/lib/librte_vhost/vhost_user.c
@@ -1563,8 +1563,10 @@
 	struct virtio_net *dev = *pdev;
 	struct vhost_vring_file file;
 	struct vhost_virtqueue *vq;
+	int expected_fds;
 
-	if (validate_msg_fds(msg, 1) != 0)
+	expected_fds = (msg->payload.u64 & VHOST_USER_VRING_NOFD_MASK) ? 0 : 1;
+	if (validate_msg_fds(msg, expected_fds) != 0)
 		return RTE_VHOST_MSG_RESULT_ERR;
 
 	file.index = msg->payload.u64 & VHOST_USER_VRING_IDX_MASK;
@@ -1588,7 +1590,10 @@ static int vhost_user_set_vring_err(struct virtio_net **pdev __rte_unused,
 			struct VhostUserMsg *msg,
 			int main_fd __rte_unused)
 {
-	if (validate_msg_fds(msg, 1) != 0)
+	int expected_fds;
+
+	expected_fds = (msg->payload.u64 & VHOST_USER_VRING_NOFD_MASK) ? 0 : 1;
+	if (validate_msg_fds(msg, expected_fds) != 0)
 		return RTE_VHOST_MSG_RESULT_ERR;
 
 	if (!(msg->payload.u64 & VHOST_USER_VRING_NOFD_MASK))
@@ -1790,8 +1795,10 @@ static int vhost_user_set_vring_err(struct virtio_net **pdev __rte_unused,
 	struct virtio_net *dev = *pdev;
 	struct vhost_vring_file file;
 	struct vhost_virtqueue *vq;
+	int expected_fds;
 
-	if (validate_msg_fds(msg, 1) != 0)
+	expected_fds = (msg->payload.u64 & VHOST_USER_VRING_NOFD_MASK) ? 0 : 1;
+	if (validate_msg_fds(msg, expected_fds) != 0)
 		return RTE_VHOST_MSG_RESULT_ERR;
 
 	file.index = msg->payload.u64 & VHOST_USER_VRING_IDX_MASK;
-- 
1.8.3.1



^ permalink raw reply	[flat|nested] 7+ messages in thread
end of thread, other threads:[~2019-11-15 13:31 UTC | newest]

Thread overview: 7+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2019-11-13 11:03 [dpdk-dev] [PATCH v2] vhost: fix vring message handling broken in some case Zhike Wang
2019-11-14  8:52 ` Maxime Coquelin
2019-11-14 10:16   ` 王志克
2019-11-14 10:23     ` Maxime Coquelin
2019-11-14 10:58       ` 王志克
2019-11-15  4:15   ` [dpdk-dev] [dpdk-stable] " Tiwei Bie
2019-11-15 13:31     ` David Marchand

This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).