From: Soheil Hassas Yeganeh <soh...@google.com> Clear tp->packets_out when purging the write queue, otherwise tcp_rearm_rto() mistakenly assumes TCP write queue is not empty. This results in NULL pointer dereference.
Also, remove the redundant `tp->packets_out = 0` from tcp_disconnect(), since tcp_disconnect() calls tcp_write_queue_purge(). Fixes: a27fd7a8ed38 (tcp: purge write queue upon RST) Reported-by: Subash Abhinov Kasiviswanathan <subas...@codeaurora.org> Reported-by: Sami Farin <hvtaifwkbgefb...@gmail.com> Tested-by: Sami Farin <hvtaifwkbgefb...@gmail.com> Signed-off-by: Eric Dumazet <eduma...@google.com> Signed-off-by: Soheil Hassas Yeganeh <soh...@google.com> Acked-by: Yuchung Cheng <ych...@google.com> Acked-by: Neal Cardwell <ncardw...@google.com> --- net/ipv4/tcp.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/net/ipv4/tcp.c b/net/ipv4/tcp.c index 4fa3f812b9ff8..9ce1c726185eb 100644 --- a/net/ipv4/tcp.c +++ b/net/ipv4/tcp.c @@ -2368,6 +2368,7 @@ void tcp_write_queue_purge(struct sock *sk) INIT_LIST_HEAD(&tcp_sk(sk)->tsorted_sent_queue); sk_mem_reclaim(sk); tcp_clear_all_retrans_hints(tcp_sk(sk)); + tcp_sk(sk)->packets_out = 0; } int tcp_disconnect(struct sock *sk, int flags) @@ -2417,7 +2418,6 @@ int tcp_disconnect(struct sock *sk, int flags) icsk->icsk_backoff = 0; tp->snd_cwnd = 2; icsk->icsk_probes_out = 0; - tp->packets_out = 0; tp->snd_ssthresh = TCP_INFINITE_SSTHRESH; tp->snd_cwnd_cnt = 0; tp->window_clamp = 0; -- 2.17.0.484.g0c8726318c-goog