tcp: Fix a connect() race with timewait sockets

First patch changes __inet_hash_nolisten() and __inet6_hash()
to get a timewait parameter to be able to unhash it from ehash
at same time the new socket is inserted in hash.

This makes sure timewait socket wont be found by a concurrent
writer in __inet_check_established()

Reported-by: kapil dakhane <kdakhane@gmail.com>
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 2 insertions, 2 deletions

diff --git a/net/ipv6/tcp_ipv6.c b/net/ipv6/tcp_ipv6.c
index aadd7cef73b3..ee9cf62458d4 100644
--- a/net/ipv6/tcp_ipv6.c
+++ b/net/ipv6/tcp_ipv6.c
@@ -96,7 +96,7 @@ static void tcp_v6_hash(struct sock *sk)
                         return;
                 }
                 local_bh_disable();
-                __inet6_hash(sk);
+                __inet6_hash(sk, NULL);
                 local_bh_enable();
         }
 }
@@ -1496,7 +1496,7 @@ static struct sock * tcp_v6_syn_recv_sock(struct sock *sk, struct sk_buff *skb,
         }
 #endif
 
-        __inet6_hash(newsk);
+        __inet6_hash(newsk, NULL);
         __inet_inherit_port(sk, newsk);
 
         return newsk;