tcp: do not rearm rsk_timer on FastOpen requests

FastOpen requests are not like other regular request sockets.

They do not yet use rsk_timer : tcp_fastopen_queue_check()
simply manually removes one expired request from fastopenq->rskq_rst
list.

Therefore, tcp_check_req() must not call mod_timer_pending(),
otherwise we crash because rsk_timer was not initialized.

Fixes: fa76ce7328b ("inet: get rid of central tcp/dccp listener timer")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: Yuchung Cheng <ycheng@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/net/ipv4/tcp_minisocks.c b/net/ipv4/tcp_minisocks.c
index d700391..2088fdc 100644 (file)
--- a/net/ipv4/tcp_minisocks.c
+++ b/net/ipv4/tcp_minisocks.c
@@ -628,10 +628,16 @@ struct sock *tcp_check_req(struct sock *sk, struct sk_buff *skb,
                                          LINUX_MIB_TCPACKSKIPPEDSYNRECV,
                                          &tcp_rsk(req)->last_oow_ack_time) &&
 
-                   !inet_rtx_syn_ack(sk, req))
-                       mod_timer_pending(&req->rsk_timer, jiffies +
-                               min(TCP_TIMEOUT_INIT << req->num_timeout,
-                                   TCP_RTO_MAX));
+                   !inet_rtx_syn_ack(sk, req)) {
+                       unsigned long expires = jiffies;
+
+                       expires += min(TCP_TIMEOUT_INIT << req->num_timeout,
+                                      TCP_RTO_MAX);
+                       if (!fastopen)
+                               mod_timer_pending(&req->rsk_timer, expires);
+                       else
+                               req->rsk_timer.expires = expires;
+               }
                return NULL;
        }