[PATCH net-next] tcp: diag: add support for request sockets to tcp_abort()

[Eric Dumazet <eric.dumazet@gmail.com>]

From: Eric Dumazet <edumazet@google.com>

Adding support for SYN_RECV request sockets to tcp_abort()
is quite easy after our tcp listener rewrite.

Note that we also need to better handle listeners, or we might
leak not yet accepted children, because of a missing
inet_csk_listen_stop() call.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Lorenzo Colitti <lorenzo@google.com>
---
 net/ipv4/tcp.c |    9 +++++++++
 1 file changed, 9 insertions(+)

diff --git a/net/ipv4/tcp.c b/net/ipv4/tcp.c
index 2c0e340518d2..cc7aaa507abf 100644
--- a/net/ipv4/tcp.c
+++ b/net/ipv4/tcp.c
@@ -3083,6 +3083,15 @@ EXPORT_SYMBOL_GPL(tcp_done);
 int tcp_abort(struct sock *sk, int err)
 {
 	if (!sk_fullsock(sk)) {
+		if (sk->sk_state == TCP_NEW_SYN_RECV) {
+			struct request_sock *req = inet_reqsk(sk);
+
+			local_bh_disable();
+			inet_csk_reqsk_queue_drop_and_put(req->rsk_listener,
+							  req);
+			local_bh_enable();
+			return 0;
+		}
 		sock_gen_put(sk);
 		return -EOPNOTSUPP;
 	}