From 12e25e1041d044d4204f2b7c54695e14e8ffb282 Mon Sep 17 00:00:00 2001 From: Eric Dumazet Date: Wed, 3 Jun 2015 23:49:21 -0700 Subject: tcp: remove redundant checks tcp_v4_rcv() checks the following before calling tcp_v4_do_rcv(): if (th->doff < sizeof(struct tcphdr) / 4) goto bad_packet; if (!pskb_may_pull(skb, th->doff * 4)) goto discard_it; So following check in tcp_v4_do_rcv() is redundant and "goto csum_err;" is wrong anyway. if (skb->len < tcp_hdrlen(skb) || ...) goto csum_err; A second check can be removed after no_tcp_socket label for same reason. Same tests can be removed in tcp_v6_do_rcv() Note : short tcp frames are not properly accounted in tcpInErrs MIB, because pskb_may_pull() failure simply drops incoming skb, we might fix this in a separate patch. Signed-off-by: Eric Dumazet Signed-off-by: David S. Miller --- net/ipv6/tcp_ipv6.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) (limited to 'net/ipv6') diff --git a/net/ipv6/tcp_ipv6.c b/net/ipv6/tcp_ipv6.c index 7be3d858cbf0..b72e1ffc6bb4 100644 --- a/net/ipv6/tcp_ipv6.c +++ b/net/ipv6/tcp_ipv6.c @@ -1250,7 +1250,7 @@ static int tcp_v6_do_rcv(struct sock *sk, struct sk_buff *skb) return 0; } - if (skb->len < tcp_hdrlen(skb) || tcp_checksum_complete(skb)) + if (tcp_checksum_complete(skb)) goto csum_err; if (sk->sk_state == TCP_LISTEN) { @@ -1442,7 +1442,7 @@ no_tcp_socket: tcp_v6_fill_cb(skb, hdr, th); - if (skb->len < (th->doff<<2) || tcp_checksum_complete(skb)) { + if (tcp_checksum_complete(skb)) { csum_error: TCP_INC_STATS_BH(net, TCP_MIB_CSUMERRORS); bad_packet: -- cgit v1.2.1