diff options
| author | Willem de Bruijn <willemb@google.com> | 2020-03-09 18:34:35 +0300 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2020-03-12 09:12:16 +0300 |
| commit | 46e4c421a053c36bf7a33dda2272481bcaf3eed3 (patch) | |
| tree | 76c4e9db0d24d3027cff0ecfc537d0e8ab373d74 /net/packet/af_packet.c | |
| parent | f3cc008bf6d59b8d93b4190e01d3e557b0040e15 (diff) | |
| download | linux-46e4c421a053c36bf7a33dda2272481bcaf3eed3.tar.xz | |
net/packet: tpacket_rcv: do not increment ring index on drop
In one error case, tpacket_rcv drops packets after incrementing the
ring producer index.
If this happens, it does not update tp_status to TP_STATUS_USER and
thus the reader is stalled for an iteration of the ring, causing out
of order arrival.
The only such error path is when virtio_net_hdr_from_skb fails due
to encountering an unknown GSO type.
Signed-off-by: Willem de Bruijn <willemb@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'net/packet/af_packet.c')
| -rw-r--r-- | net/packet/af_packet.c | 13 |
1 files changed, 7 insertions, 6 deletions
diff --git a/net/packet/af_packet.c b/net/packet/af_packet.c index 30c6879d6774..e5b0986215d2 100644 --- a/net/packet/af_packet.c +++ b/net/packet/af_packet.c @@ -2274,6 +2274,13 @@ static int tpacket_rcv(struct sk_buff *skb, struct net_device *dev, TP_STATUS_KERNEL, (macoff+snaplen)); if (!h.raw) goto drop_n_account; + + if (do_vnet && + virtio_net_hdr_from_skb(skb, h.raw + macoff - + sizeof(struct virtio_net_hdr), + vio_le(), true, 0)) + goto drop_n_account; + if (po->tp_version <= TPACKET_V2) { packet_increment_rx_head(po, &po->rx_ring); /* @@ -2286,12 +2293,6 @@ static int tpacket_rcv(struct sk_buff *skb, struct net_device *dev, status |= TP_STATUS_LOSING; } - if (do_vnet && - virtio_net_hdr_from_skb(skb, h.raw + macoff - - sizeof(struct virtio_net_hdr), - vio_le(), true, 0)) - goto drop_n_account; - po->stats.stats1.tp_packets++; if (copy_skb) { status |= TP_STATUS_COPY; |