From 49c71586a6a94de168a26ec454eb8ea282ddd827 Mon Sep 17 00:00:00 2001 From: Tonghao Zhang Date: Mon, 21 Aug 2017 23:33:48 -0700 Subject: [PATCH] tcp: Get a proper dst before checking it. tcp_peer_is_proven needs a proper route to make the determination, but dst always is NULL. This bug may be there at the beginning of git tree. This does not look serious enough to deserve backports to stable versions. Signed-off-by: Tonghao Zhang Acked-by: Eric Dumazet Signed-off-by: David S. Miller --- net/ipv4/tcp_input.c | 9 ++++----- 1 file changed, 4 insertions(+), 5 deletions(-) diff --git a/net/ipv4/tcp_input.c b/net/ipv4/tcp_input.c index ddc854728a60..ab908949ee95 100644 --- a/net/ipv4/tcp_input.c +++ b/net/ipv4/tcp_input.c @@ -6111,6 +6111,10 @@ int tcp_conn_request(struct request_sock_ops *rsk_ops, if (tmp_opt.tstamp_ok) tcp_rsk(req)->ts_off = af_ops->init_ts_off(net, skb); + dst = af_ops->route_req(sk, &fl, req); + if (!dst) + goto drop_and_free; + if (!want_cookie && !isn) { /* Kill the following clause, if you dislike this way. */ if (!net->ipv4.sysctl_tcp_syncookies && @@ -6131,11 +6135,6 @@ int tcp_conn_request(struct request_sock_ops *rsk_ops, isn = af_ops->init_seq(skb); } - if (!dst) { - dst = af_ops->route_req(sk, &fl, req); - if (!dst) - goto drop_and_free; - } tcp_ecn_create_request(req, skb, sk, dst);