| Message ID | 1530108136-4984-3-git-send-email-magnus.karlsson@intel.com |
|---|---|
| State | Changes Requested, archived |
| Delegated to: | BPF Maintainers |
| Headers | show |
| Series | Bug fixes to the SKB TX path of AF_XDP | expand |
On Wed, Jun 27, 2018 at 7:02 AM, Magnus Karlsson <magnus.karlsson@intel.com> wrote: > 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> Acked-by: Song Liu <songliubraving@fb.com> > --- > net/xdp/xsk.c | 6 +++--- > 1 file changed, 3 insertions(+), 3 deletions(-) > > diff --git a/net/xdp/xsk.c b/net/xdp/xsk.c > index 3b3410ada097..d482f727f4c2 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); > } > > out: > -- > 2.7.4 >
diff --git a/net/xdp/xsk.c b/net/xdp/xsk.c index 3b3410ada097..d482f727f4c2 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); } out:
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> --- net/xdp/xsk.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-)