4.16-stable review patch. If anyone has any objections, please let me know.
------------------
From: Soheil Hassas Yeganeh <soh...@google.com>
[ Upstream commit bffd168c3fc5cc7d2bad4c668fa90e7a9010db4b ]
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>
Signed-off-by: David S. Miller <da...@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gre...@linuxfoundation.org>
---
net/ipv4/tcp.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
--- a/net/ipv4/tcp.c
+++ b/net/ipv4/tcp.c
@@ -2385,6 +2385,7 @@ void tcp_write_queue_purge(struct sock *
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)
@@ -2434,7 +2435,6 @@ int tcp_disconnect(struct sock *sk, int
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;
