netdev - [RFC PATCH v4 3/4] virtio/vsock: don't drop skbuff on copy failure

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <e29e788a-51d7-f733-85a5-707044f54dd6@sberdevices.ru>
Date:   Thu, 9 Mar 2023 23:28:01 +0300
From:   Arseniy Krasnov <avkrasnov@...rdevices.ru>
To:     Stefan Hajnoczi <stefanha@...hat.com>,
        Stefano Garzarella <sgarzare@...hat.com>,
        "David S. Miller" <davem@...emloft.net>,
        Eric Dumazet <edumazet@...gle.com>,
        Jakub Kicinski <kuba@...nel.org>,
        Paolo Abeni <pabeni@...hat.com>,
        Bobby Eshleman <bobby.eshleman@...edance.com>
CC:     <kvm@...r.kernel.org>, <virtualization@...ts.linux-foundation.org>,
        <netdev@...r.kernel.org>, <linux-kernel@...r.kernel.org>,
        <kernel@...rdevices.ru>, <oxffffaa@...il.com>,
        <avkrasnov@...rdevices.ru>
Subject: [RFC PATCH v4 3/4] virtio/vsock: don't drop skbuff on copy failure

This returns behaviour of SOCK_STREAM read as before skbuff usage. When
copying to user fails current skbuff won't be dropped, but returned to
sockets's queue. Technically instead of 'skb_dequeue()', 'skb_peek()' is
called and when skbuff becomes empty, it is removed from queue by
'__skb_unlink()'.

Fixes: 71dc9ec9ac7d ("virtio/vsock: replace virtio_vsock_pkt with sk_buff")
Signed-off-by: Arseniy Krasnov <AVKrasnov@...rdevices.ru>
---
 net/vmw_vsock/virtio_transport_common.c | 5 ++---
 1 file changed, 2 insertions(+), 3 deletions(-)

diff --git a/net/vmw_vsock/virtio_transport_common.c b/net/vmw_vsock/virtio_transport_common.c
index 9a411475e201..6564192e7f20 100644
--- a/net/vmw_vsock/virtio_transport_common.c
+++ b/net/vmw_vsock/virtio_transport_common.c
@@ -364,7 +364,7 @@ virtio_transport_stream_do_dequeue(struct vsock_sock *vsk,
 
 	spin_lock_bh(&vvs->rx_lock);
 	while (total < len && !skb_queue_empty(&vvs->rx_queue)) {
-		skb = __skb_dequeue(&vvs->rx_queue);
+		skb = skb_peek(&vvs->rx_queue);
 
 		bytes = len - total;
 		if (bytes > skb->len)
@@ -388,9 +388,8 @@ virtio_transport_stream_do_dequeue(struct vsock_sock *vsk,
 			u32 pkt_len = le32_to_cpu(virtio_vsock_hdr(skb)->len);
 
 			virtio_transport_dec_rx_pkt(vvs, pkt_len);
+			__skb_unlink(skb, &vvs->rx_queue);
 			consume_skb(skb);
-		} else {
-			__skb_queue_head(&vvs->rx_queue, skb);
 		}
 	}
 
-- 
2.25.1