diff options
| author | Eric Dumazet <eric.dumazet@gmail.com> | 2011-12-02 23:41:42 +0000 |
|---|---|---|
| committer | Paul Gortmaker <paul.gortmaker@windriver.com> | 2014-02-10 16:10:58 -0500 |
| commit | cc5e45629c6783c2b77d881f61ff52a68b8f0c8e (patch) | |
| tree | e6ac1fb8b3cbdf658ffb2d641bdad43682f8b99c /net | |
| parent | 450958657a8d2b4a50f7e72a565f014bfa464ca9 (diff) | |
tcp: drop SYN+FIN messages
commit fdf5af0daf8019cec2396cdef8fb042d80fe71fa upstream.
Denys Fedoryshchenko reported that SYN+FIN attacks were bringing his
linux machines to their limits.
Dont call conn_request() if the TCP flags includes SYN flag
Reported-by: Denys Fedoryshchenko <denys@visp.net.lb>
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Diffstat (limited to 'net')
| -rw-r--r-- | net/ipv4/tcp_input.c | 2 |
1 files changed, 2 insertions, 0 deletions
diff --git a/net/ipv4/tcp_input.c b/net/ipv4/tcp_input.c index df5de7dd22d2..20af12ae55a7 100644 --- a/net/ipv4/tcp_input.c +++ b/net/ipv4/tcp_input.c @@ -5737,6 +5737,8 @@ int tcp_rcv_state_process(struct sock *sk, struct sk_buff *skb, goto discard; if (th->syn) { + if (th->fin) + goto discard; if (icsk->icsk_af_ops->conn_request(sk, skb) < 0) return 1; |