From: Zhike Wang <wangzk320@163.com> 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: 1f6147d9a01f ("vhost: fix possible denial of service by leaking FDs") Cc: stable@dpdk.org Signed-off-by: Zhike Wang <wangzk320@163.com> Reviewed-by: Maxime Coquelin <maxime.coquelin@redhat.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 d4643dc350..155394a6d9 100644 --- a/lib/librte_vhost/vhost_user.c +++ b/lib/librte_vhost/vhost_user.c @@ -1409,6 +1409,7 @@ vhost_user_msg_handler(int vid, int fd) struct VhostUserMsg msg; int ret; int unlock_required = 0; + int expected_fds; dev = get_device(vid); if (dev == NULL) @@ -1586,20 +1587,26 @@ vhost_user_msg_handler(int vid, int fd) break; case VHOST_USER_SET_VRING_KICK: - 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 -1; vhost_user_set_vring_kick(&dev, &msg); break; case VHOST_USER_SET_VRING_CALL: - 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 -1; vhost_user_set_vring_call(dev, &msg); break; case VHOST_USER_SET_VRING_ERR: - 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 -1; if (!(msg.payload.u64 & VHOST_USER_VRING_NOFD_MASK)) -- 2.21.0
On Fri, Nov 15, 2019 at 11:36:30AM +0100, Maxime Coquelin wrote:
> From: Zhike Wang <wangzk320@163.com>
>
> 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: 1f6147d9a01f ("vhost: fix possible denial of service by leaking FDs")
> Cc: stable@dpdk.org
>
> Signed-off-by: Zhike Wang <wangzk320@163.com>
> Reviewed-by: Maxime Coquelin <maxime.coquelin@redhat.com>
> ---
> lib/librte_vhost/vhost_user.c | 13 ++++++++++---
> 1 file changed, 10 insertions(+), 3 deletions(-)
Reviewed-by: Tiwei Bie <tiwei.bie@intel.com>
Thanks!
Tiwei
On Fri, 2019-11-15 at 20:24 +0800, Tiwei Bie wrote:
> On Fri, Nov 15, 2019 at 11:36:30AM +0100, Maxime Coquelin wrote:
> > From: Zhike Wang <
> > wangzk320@163.com
> > >
> >
> > 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: 1f6147d9a01f ("vhost: fix possible denial of service by
> > leaking FDs")
> > Cc:
> > stable@dpdk.org
> >
> >
> > Signed-off-by: Zhike Wang <
> > wangzk320@163.com
> > >
> > Reviewed-by: Maxime Coquelin <
> > maxime.coquelin@redhat.com
> > >
> > ---
> > lib/librte_vhost/vhost_user.c | 13 ++++++++++---
> > 1 file changed, 10 insertions(+), 3 deletions(-)
>
> Reviewed-by: Tiwei Bie <
> tiwei.bie@intel.com
> >
>
> Thanks!
> Tiwei
Thanks, applied
--
Kind regards,
Luca Boccassi