From 805c4bc05705fb2b71ec970960b456eee9900953 Mon Sep 17 00:00:00 2001 From: Eric Dumazet Date: Thu, 5 Nov 2015 11:07:13 -0800 Subject: tcp: fix req->saved_syn race For the reasons explained in commit ce1050089c96 ("tcp/dccp: fix ireq->pktopts race"), we need to make sure we do not access req->saved_syn unless we own the request sock. This fixes races for listeners using TCP_SAVE_SYN option. Fixes: e994b2f0fb92 ("tcp: do not lock listener to process SYN packets") Fixes: 079096f103fa ("tcp/dccp: install syn_recv requests into ehash table") Signed-off-by: Eric Dumazet Reported-by: Ying Cai Signed-off-by: David S. Miller --- include/linux/tcp.h | 7 +++++++ 1 file changed, 7 insertions(+) (limited to 'include/linux/tcp.h') diff --git a/include/linux/tcp.h b/include/linux/tcp.h index c906f4534581..b386361ba3e8 100644 --- a/include/linux/tcp.h +++ b/include/linux/tcp.h @@ -397,6 +397,13 @@ static inline void fastopen_queue_tune(struct sock *sk, int backlog) queue->fastopenq.max_qlen = min_t(unsigned int, backlog, somaxconn); } +static inline void tcp_move_syn(struct tcp_sock *tp, + struct request_sock *req) +{ + tp->saved_syn = req->saved_syn; + req->saved_syn = NULL; +} + static inline void tcp_saved_syn_free(struct tcp_sock *tp) { kfree(tp->saved_syn); -- cgit v1.2.3-70-g09d2