tcp: clear tp->total_retrans in tcp_disconnect()

BugLink: https://bugs.launchpad.net/bugs/1864775

[ Upstream commit c13c48c0 ]

total_retrans needs to be cleared in tcp_disconnect().

tcp_disconnect() is rarely used, but it is worth fixing it.

Fixes: 1da177e4 ("Linux-2.6.12-rc2")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: SeongJae Park <sjpark@amazon.de>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Khalid Elmously <khalid.elmously@canonical.com>
Signed-off-by: Kleber Sacilotto de Souza <kleber.souza@canonical.com>

net/ipv4/tcp.c

@@ -2261,6 +2261,7 @@ int tcp_disconnect(struct sock *sk, int flags)
 	tp->window_clamp = 0;
 	tcp_set_ca_state(sk, TCP_CA_Open);
 	tcp_clear_retrans(tp);
+	tp->total_retrans = 0;
 	inet_csk_delack_init(sk);
 	/* Initialize rcv_mss to TCP_MIN_MSS to avoid division by 0
 	 * issue in __tcp_select_window()