From: Willem de Bruijn willemb@google.com
[ Upstream commit 46e4c421a053c36bf7a33dda2272481bcaf3eed3 ]
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 Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- net/packet/af_packet.c | 13 +++++++------ 1 file changed, 7 insertions(+), 6 deletions(-)
--- a/net/packet/af_packet.c +++ b/net/packet/af_packet.c @@ -2260,6 +2260,13 @@ static int tpacket_rcv(struct sk_buff *s 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); /* @@ -2272,12 +2279,6 @@ static int tpacket_rcv(struct sk_buff *s 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;