From: Yunjian Wang <wangyunjian@huawei.com> mainline inclusion from mainline-5.12-rc1 commit dc9c9e72ff3ba01ae63e6263ac26234ba1869cd7 category: bugfix bugzilla: https://gitee.com/openeuler/kernel/issues/I4MFVB CVE: NA ------------------------------------------------- Currently the driver doesn't drop a packet which can't be sent by tun (e.g bad packet). In this case, the driver will always process the same packet lead to the tx queue stuck. To fix this issue: 1. in the case of persistent failure (e.g bad packet), the driver can skip this descriptor by ignoring the error. 2. in the case of transient failure (e.g -ENOBUFS, -EAGAIN and -ENOMEM), the driver schedules the worker to try again. Signed-off-by: Yunjian Wang <wangyunjian@huawei.com> Acked-by: Jason Wang <jasowang@redhat.com> Acked-by: Willem de Bruijn <willemb@google.com> Acked-by: Michael S. Tsirkin <mst@redhat.com> Link: https://lore.kernel.org/r/1610685980-38608-1-git-send-email-wangyunjian@huaw... Signed-off-by: Jakub Kicinski <kuba@kernel.org> Signed-off-by: Lu Wei <luwei32@huawei.com> Reviewed-by: Wei Yongjun <weiyongjun1@huawei.com> Signed-off-by: Zheng Zengkai <zhengzengkai@huawei.com> --- drivers/vhost/net.c | 26 ++++++++++++++------------ 1 file changed, 14 insertions(+), 12 deletions(-) diff --git a/drivers/vhost/net.c b/drivers/vhost/net.c index da02c3e96e7b..666c2d5b6673 100644 --- a/drivers/vhost/net.c +++ b/drivers/vhost/net.c @@ -836,14 +836,15 @@ static void handle_tx_copy(struct vhost_net *net, struct socket *sock) msg.msg_flags &= ~MSG_MORE; } - /* TODO: Check specific error and bomb out unless ENOBUFS? */ err = sock->ops->sendmsg(sock, &msg, len); if (unlikely(err < 0)) { - vhost_discard_vq_desc(vq, 1); - vhost_net_enable_vq(net, vq); - break; - } - if (err != len) + if (err == -EAGAIN || err == -ENOMEM || err == -ENOBUFS) { + vhost_discard_vq_desc(vq, 1); + vhost_net_enable_vq(net, vq); + break; + } + pr_debug("Fail to send packet: err %d", err); + } else if (unlikely(err != len)) pr_debug("Truncated TX packet: len %d != %zd\n", err, len); done: @@ -931,7 +932,6 @@ static void handle_tx_zerocopy(struct vhost_net *net, struct socket *sock) msg.msg_flags &= ~MSG_MORE; } - /* TODO: Check specific error and bomb out unless ENOBUFS? */ err = sock->ops->sendmsg(sock, &msg, len); if (unlikely(err < 0)) { if (zcopy_used) { @@ -940,11 +940,13 @@ static void handle_tx_zerocopy(struct vhost_net *net, struct socket *sock) nvq->upend_idx = ((unsigned)nvq->upend_idx - 1) % UIO_MAXIOV; } - vhost_discard_vq_desc(vq, 1); - vhost_net_enable_vq(net, vq); - break; - } - if (err != len) + if (err == -EAGAIN || err == -ENOMEM || err == -ENOBUFS) { + vhost_discard_vq_desc(vq, 1); + vhost_net_enable_vq(net, vq); + break; + } + pr_debug("Fail to send packet: err %d", err); + } else if (unlikely(err != len)) pr_debug("Truncated TX packet: " " len %d != %zd\n", err, len); if (!zcopy_used) -- 2.20.1