path: root/net/xdp
diff options
authorMagnus Karlsson <magnus.karlsson@intel.com>2018-06-29 09:48:18 +0200
committerAlexei Starovoitov <ast@kernel.org>2018-07-02 18:37:11 -0700
commitfe5886852601fb2593cbc5a7549ef9fd2ef481ba (patch)
tree9a70b5726fb7b432289dd130d5d871d0a61de56b /net/xdp
parentxsk: fix potential lost completion message in SKB path (diff)
xsk: frame could be completed more than once in SKB path
Fixed a bug in which a frame could be completed more than once when an error was returned from dev_direct_xmit(). The code erroneously retried sending the message leading to multiple calls to the SKB destructor and therefore multiple completions of the same buffer to user space. The error code in this case has been changed from EAGAIN to EBUSY in order to tell user space that the sending of the packet failed and the buffer has been return to user space through the completion queue. Fixes: 35fcde7f8deb ("xsk: support for Tx") Signed-off-by: Magnus Karlsson <magnus.karlsson@intel.com> Reported-by: Pavel Odintsov <pavel@fastnetmon.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Diffstat (limited to 'net/xdp')
1 files changed, 3 insertions, 3 deletions
diff --git a/net/xdp/xsk.c b/net/xdp/xsk.c
index 59fb7d3c36a3..15aca73805fc 100644
--- a/net/xdp/xsk.c
+++ b/net/xdp/xsk.c
@@ -268,15 +268,15 @@ static int xsk_generic_xmit(struct sock *sk, struct msghdr *m,
skb->destructor = xsk_destruct_skb;
err = dev_direct_xmit(skb, xs->queue_id);
+ xskq_discard_desc(xs->tx);
/* Ignore NET_XMIT_CN as packet might have been sent */
if (err == NET_XMIT_DROP || err == NETDEV_TX_BUSY) {
- err = -EAGAIN;
- /* SKB consumed by dev_direct_xmit() */
+ /* SKB completed but not sent */
+ err = -EBUSY;
goto out;
sent_frame = true;
- xskq_discard_desc(xs->tx);