diff options
Diffstat (limited to 'net/ipv4/tcp_ipv4.c')
| -rw-r--r-- | net/ipv4/tcp_ipv4.c | 35 |
1 files changed, 31 insertions, 4 deletions
diff --git a/net/ipv4/tcp_ipv4.c b/net/ipv4/tcp_ipv4.c index 7158d4f8dae4..a75bf48d7950 100644 --- a/net/ipv4/tcp_ipv4.c +++ b/net/ipv4/tcp_ipv4.c @@ -1175,6 +1175,7 @@ static bool tcp_v4_inbound_md5_hash(const struct sock *sk, NULL, skb); if (genhash || memcmp(hash_location, newhash, 16) != 0) { + NET_INC_STATS(sock_net(sk), LINUX_MIB_TCPMD5FAILURE); net_info_ratelimited("MD5 Hash failed for (%pI4, %d)->(%pI4, %d)%s\n", &iph->saddr, ntohs(th->source), &iph->daddr, ntohs(th->dest), @@ -1537,6 +1538,34 @@ bool tcp_prequeue(struct sock *sk, struct sk_buff *skb) } EXPORT_SYMBOL(tcp_prequeue); +bool tcp_add_backlog(struct sock *sk, struct sk_buff *skb) +{ + u32 limit = sk->sk_rcvbuf + sk->sk_sndbuf; + + /* Only socket owner can try to collapse/prune rx queues + * to reduce memory overhead, so add a little headroom here. + * Few sockets backlog are possibly concurrently non empty. + */ + limit += 64*1024; + + /* In case all data was pulled from skb frags (in __pskb_pull_tail()), + * we can fix skb->truesize to its real value to avoid future drops. + * This is valid because skb is not yet charged to the socket. + * It has been noticed pure SACK packets were sometimes dropped + * (if cooked by drivers without copybreak feature). + */ + if (!skb->data_len) + skb->truesize = SKB_TRUESIZE(skb_end_offset(skb)); + + if (unlikely(sk_add_backlog(sk, skb, limit))) { + bh_unlock_sock(sk); + __NET_INC_STATS(sock_net(sk), LINUX_MIB_TCPBACKLOGDROP); + return true; + } + return false; +} +EXPORT_SYMBOL(tcp_add_backlog); + /* * From tcp_input.c */ @@ -1608,6 +1637,7 @@ process: sk = req->rsk_listener; if (unlikely(tcp_v4_inbound_md5_hash(sk, skb))) { + sk_drops_add(sk, skb); reqsk_put(req); goto discard_it; } @@ -1666,10 +1696,7 @@ process: if (!sock_owned_by_user(sk)) { if (!tcp_prequeue(sk, skb)) ret = tcp_v4_do_rcv(sk, skb); - } else if (unlikely(sk_add_backlog(sk, skb, - sk->sk_rcvbuf + sk->sk_sndbuf))) { - bh_unlock_sock(sk); - __NET_INC_STATS(net, LINUX_MIB_TCPBACKLOGDROP); + } else if (tcp_add_backlog(sk, skb)) { goto discard_and_relse; } bh_unlock_sock(sk); |