target/linux/generic/patches-4.1/103-packet_allow_empty_payload.patch

   1 Fix a regression in the af_packet code that was breaking PPPoE
   2
   3 pppd sends packets with only a header and no payload.
   4
   5 Signed-off-by: Felix Fietkau <nbd@openwrt.org>
   6
   7 --- a/net/packet/af_packet.c
   8 +++ b/net/packet/af_packet.c
   9 @@ -2112,7 +2112,7 @@ static void tpacket_destruct_skb(struct
  10  static bool ll_header_truncated(const struct net_device *dev, int len)
  11  {
  12         /* net device doesn't like empty head */
  13 -       if (unlikely(len <= dev->hard_header_len)) {
  14 +       if (unlikely(len < dev->hard_header_len)) {
  15                 net_warn_ratelimited("%s: packet size is too short (%d <= %d)\n",
  16                                      current->comm, len, dev->hard_header_len);
  17                 return true;