diff options
author | Yunjian Wang <wangyunjian@huawei.com> | 2020-12-29 05:01:48 +0300 |
---|---|---|
committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2021-01-12 22:10:19 +0300 |
commit | cf7dd7f3bec70fb52a127388facd832157a877c9 (patch) | |
tree | eb2dac5da481deb6af41aa3751a4f6943dae1e10 /drivers/vhost | |
parent | 40a3682f93eafe01ca90059fdd1ca9f32446bf14 (diff) | |
download | linux-cf7dd7f3bec70fb52a127388facd832157a877c9.tar.xz |
vhost_net: fix ubuf refcount incorrectly when sendmsg fails
[ Upstream commit 01e31bea7e622f1890c274f4aaaaf8bccd296aa5 ]
Currently the vhost_zerocopy_callback() maybe be called to decrease
the refcount when sendmsg fails in tun. The error handling in vhost
handle_tx_zerocopy() will try to decrease the same refcount again.
This is wrong. To fix this issue, we only call vhost_net_ubuf_put()
when vq->heads[nvq->desc].len == VHOST_DMA_IN_PROGRESS.
Fixes: bab632d69ee4 ("vhost: vhost TX zero-copy support")
Signed-off-by: Yunjian Wang <wangyunjian@huawei.com>
Acked-by: Willem de Bruijn <willemb@google.com>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Acked-by: Jason Wang <jasowang@redhat.com>
Link: https://lore.kernel.org/r/1609207308-20544-1-git-send-email-wangyunjian@huawei.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'drivers/vhost')
-rw-r--r-- | drivers/vhost/net.c | 6 |
1 files changed, 3 insertions, 3 deletions
diff --git a/drivers/vhost/net.c b/drivers/vhost/net.c index 88c8c158ec25..0c7bbc92b22a 100644 --- a/drivers/vhost/net.c +++ b/drivers/vhost/net.c @@ -613,6 +613,7 @@ static void handle_tx_zerocopy(struct vhost_net *net, struct socket *sock) size_t len, total_len = 0; int err; struct vhost_net_ubuf_ref *uninitialized_var(ubufs); + struct ubuf_info *ubuf; bool zcopy_used; int sent_pkts = 0; @@ -645,9 +646,7 @@ static void handle_tx_zerocopy(struct vhost_net *net, struct socket *sock) /* use msg_control to pass vhost zerocopy ubuf info to skb */ if (zcopy_used) { - struct ubuf_info *ubuf; ubuf = nvq->ubuf_info + nvq->upend_idx; - vq->heads[nvq->upend_idx].id = cpu_to_vhost32(vq, head); vq->heads[nvq->upend_idx].len = VHOST_DMA_IN_PROGRESS; ubuf->callback = vhost_zerocopy_callback; @@ -675,7 +674,8 @@ static void handle_tx_zerocopy(struct vhost_net *net, struct socket *sock) err = sock->ops->sendmsg(sock, &msg, len); if (unlikely(err < 0)) { if (zcopy_used) { - vhost_net_ubuf_put(ubufs); + if (vq->heads[ubuf->desc].len == VHOST_DMA_IN_PROGRESS) + vhost_net_ubuf_put(ubufs); nvq->upend_idx = ((unsigned)nvq->upend_idx - 1) % UIO_MAXIOV; } |