From 5852a2b573f7a3a29df46296e56aa3491e589cdf Mon Sep 17 00:00:00 2001 From: Arseniy Krasnov Date: Tue, 14 Mar 2023 14:05:48 +0300 Subject: [PATCH] virtio/vsock: don't use skbuff state to account credit commit 077706165717686a2a6a71405fef036cd5b37ae0 upstream. 'skb->len' can vary when we partially read the data, this complicates the calculation of credit to be updated in 'virtio_transport_inc_rx_pkt()/ virtio_transport_dec_rx_pkt()'. Also in 'virtio_transport_dec_rx_pkt()' we were miscalculating the credit since 'skb->len' was redundant. For these reasons, let's replace the use of skbuff state to calculate new 'rx_bytes'/'fwd_cnt' values with explicit value as input argument. This makes code more simple, because it is not needed to change skbuff state before each call to update 'rx_bytes'/'fwd_cnt'. Fixes: 71dc9ec9ac7d ("virtio/vsock: replace virtio_vsock_pkt with sk_buff") Signed-off-by: Arseniy Krasnov Reviewed-by: Stefano Garzarella Acked-by: Bobby Eshleman Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman --- net/vmw_vsock/virtio_transport_common.c | 23 +++++++++++------------ 1 file changed, 11 insertions(+), 12 deletions(-) diff --git a/net/vmw_vsock/virtio_transport_common.c b/net/vmw_vsock/virtio_transport_common.c index 73e5093..c06d03b 100644 --- a/net/vmw_vsock/virtio_transport_common.c +++ b/net/vmw_vsock/virtio_transport_common.c @@ -241,21 +241,18 @@ static int virtio_transport_send_pkt_info(struct vsock_sock *vsk, } static bool virtio_transport_inc_rx_pkt(struct virtio_vsock_sock *vvs, - struct sk_buff *skb) + u32 len) { - if (vvs->rx_bytes + skb->len > vvs->buf_alloc) + if (vvs->rx_bytes + len > vvs->buf_alloc) return false; - vvs->rx_bytes += skb->len; + vvs->rx_bytes += len; return true; } static void virtio_transport_dec_rx_pkt(struct virtio_vsock_sock *vvs, - struct sk_buff *skb) + u32 len) { - int len; - - len = skb_headroom(skb) - sizeof(struct virtio_vsock_hdr) - skb->len; vvs->rx_bytes -= len; vvs->fwd_cnt += len; } @@ -388,7 +385,9 @@ virtio_transport_stream_do_dequeue(struct vsock_sock *vsk, skb_pull(skb, bytes); if (skb->len == 0) { - virtio_transport_dec_rx_pkt(vvs, skb); + u32 pkt_len = le32_to_cpu(virtio_vsock_hdr(skb)->len); + + virtio_transport_dec_rx_pkt(vvs, pkt_len); consume_skb(skb); } else { __skb_queue_head(&vvs->rx_queue, skb); @@ -437,17 +436,17 @@ static int virtio_transport_seqpacket_do_dequeue(struct vsock_sock *vsk, while (!msg_ready) { struct virtio_vsock_hdr *hdr; + size_t pkt_len; skb = __skb_dequeue(&vvs->rx_queue); if (!skb) break; hdr = virtio_vsock_hdr(skb); + pkt_len = (size_t)le32_to_cpu(hdr->len); if (dequeued_len >= 0) { - size_t pkt_len; size_t bytes_to_copy; - pkt_len = (size_t)le32_to_cpu(hdr->len); bytes_to_copy = min(user_buf_len, pkt_len); if (bytes_to_copy) { @@ -484,7 +483,7 @@ static int virtio_transport_seqpacket_do_dequeue(struct vsock_sock *vsk, msg->msg_flags |= MSG_EOR; } - virtio_transport_dec_rx_pkt(vvs, skb); + virtio_transport_dec_rx_pkt(vvs, pkt_len); kfree_skb(skb); } @@ -1040,7 +1039,7 @@ virtio_transport_recv_enqueue(struct vsock_sock *vsk, spin_lock_bh(&vvs->rx_lock); - can_enqueue = virtio_transport_inc_rx_pkt(vvs, skb); + can_enqueue = virtio_transport_inc_rx_pkt(vvs, len); if (!can_enqueue) { free_pkt = true; goto out; -- 2.7.4