Stefano Garzarella
2023-Mar-06 12:07 UTC
[RFC PATCH v2 3/4] virtio/vsock: free skb on data copy failure
On Sun, Mar 05, 2023 at 11:08:38PM +0300, Arseniy Krasnov wrote:>This fixes two things in case when 'memcpy_to_msg()' fails: >1) Update credit parameters of the socket, like this skbuff was > copied to user successfully. This is needed because when skbuff was > received it's length was used to update 'rx_bytes', thus when we drop > skbuff here, we must account rest of it's data in 'rx_bytes'. >2) Free skbuff which was removed from socket's queue. > >Fixes: 71dc9ec9ac7d ("virtio/vsock: replace virtio_vsock_pkt with sk_buff") >Signed-off-by: Arseniy Krasnov <AVKrasnov at sberdevices.ru> >--- > net/vmw_vsock/virtio_transport_common.c | 6 +++++- > 1 file changed, 5 insertions(+), 1 deletion(-) > >diff --git a/net/vmw_vsock/virtio_transport_common.c b/net/vmw_vsock/virtio_transport_common.c >index 30b0539990ba..ffb1af4f2b52 100644 >--- a/net/vmw_vsock/virtio_transport_common.c >+++ b/net/vmw_vsock/virtio_transport_common.c >@@ -379,8 +379,12 @@ virtio_transport_stream_do_dequeue(struct vsock_sock *vsk, > spin_unlock_bh(&vvs->rx_lock); > > err = memcpy_to_msg(msg, skb->data, bytes); >- if (err) >+ if (err) { >+ skb_pull(skb, skb->len); >+ virtio_transport_dec_rx_pkt(vvs, skb); >+ consume_skb(skb);I'm not sure it's the right thing to do, if we fail to copy the content into the user's buffer, I think we should queue it again. In fact, before commit 71dc9ec9ac7d ("virtio/vsock: replace virtio_vsock_pkt with sk_buff"), we used to remove the packet from the rx_queue, only if memcpy_to_msg() was successful. Maybe it is better to do as we did before and use skb_peek() at the beginning of the loop and __skb_unlink() when skb->len == 0. Thanks, Stefano> goto out; >+ } > > spin_lock_bh(&vvs->rx_lock); > >-- >2.25.1 >
Apparently Analagous Threads
- [RFC PATCH v2 1/4] virtio/vsock: fix 'rx_bytes'/'fwd_cnt' calculation
- [RFC PATCH v4 2/4] virtio/vsock: remove redundant 'skb_pull()' call
- [PATCH net-next v5 1/4] vsock/virtio/vhost: read data from non-linear skb
- [RFC PATCH v3 0/4] several updates to virtio/vsock
- [RFC PATCH v2 2/4] virtio/vsock: remove all data from sk_buff