From 9403cf2302588022d06f1878b072d3f6933021f0 Mon Sep 17 00:00:00 2001 From: Guillaume Nault Date: Tue, 19 Mar 2019 16:05:44 +0100 Subject: tcp: free request sock directly upon TFO or syncookies error Since the request socket is created locally, it'd make more sense to use reqsk_free() instead of reqsk_put() in TFO and syncookies' error path. However, tcp_get_cookie_sock() may set ->rsk_refcnt before freeing the socket; tcp_conn_request() may also have non-null ->rsk_refcnt because of tcp_try_fastopen(). In both cases 'req' hasn't been exposed to the outside world and is safe to free immediately, but that'd trigger the WARN_ON_ONCE in reqsk_free(). Define __reqsk_free() for these situations where we know nobody's referencing the socket, even though ->rsk_refcnt might be non-null. Now we can consolidate the error path of tcp_get_cookie_sock() and tcp_conn_request(). Signed-off-by: Guillaume Nault Signed-off-by: Eric Dumazet Signed-off-by: David S. Miller --- net/ipv4/syncookies.c | 17 ++++++++--------- 1 file changed, 8 insertions(+), 9 deletions(-) (limited to 'net/ipv4/syncookies.c') diff --git a/net/ipv4/syncookies.c b/net/ipv4/syncookies.c index e531344611a0..008545f63667 100644 --- a/net/ipv4/syncookies.c +++ b/net/ipv4/syncookies.c @@ -216,16 +216,15 @@ struct sock *tcp_get_cookie_sock(struct sock *sk, struct sk_buff *skb, refcount_set(&req->rsk_refcnt, 1); tcp_sk(child)->tsoffset = tsoff; sock_rps_save_rxhash(child, skb); - if (!inet_csk_reqsk_queue_add(sk, req, child)) { - bh_unlock_sock(child); - sock_put(child); - child = NULL; - reqsk_put(req); - } - } else { - reqsk_free(req); + if (inet_csk_reqsk_queue_add(sk, req, child)) + return child; + + bh_unlock_sock(child); + sock_put(child); } - return child; + __reqsk_free(req); + + return NULL; } EXPORT_SYMBOL(tcp_get_cookie_sock); -- cgit v1.2.3