diff options
| author | Eric Dumazet <eric.dumazet@gmail.com> | 2011-12-02 23:41:42 +0000 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2012-07-19 08:58:22 -0700 |
| commit | 1a4eda9788a542347dfc2b1684636bcbe2ee3f79 (patch) | |
| tree | dd2acb8008f97607e16c24f0a5c539f6f3e4711f /net | |
| parent | 9c5d9de68ea54ae743b1cb36645c96b8fdcc1c8d (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>
Cc: Ben Hutchings <ben@decadent.org.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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 7410a8c28e1..6e33b79cb68 100644 --- a/net/ipv4/tcp_input.c +++ b/net/ipv4/tcp_input.c @@ -5761,6 +5761,8 @@ 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; |