tcp: fix TIME_WAIT socket reference leak on PSP policy failure

Release the TIME_WAIT socket reference and jump to discard_it
upon PSP policy failure in both IPv4 and IPv6 receive paths.
This prevents a memory leak of tcp_tw_bucket structures.

Fixes: 659a289 ("tcp: add datapath logic for PSP with inline key exchange")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: Kuniyuki Iwashima <kuniyu@google.com>
Reviewed-by: Daniel Zahka <daniel.zahka@gmail.com>
Link: https://patch.msgid.link/20260710181317.4060230-1-edumazet@google.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>

Author: edumazet

net/ipv4/tcp_ipv4.c

@@ -2318,8 +2318,10 @@ int tcp_v4_rcv(struct sk_buff *skb)
 		}
 
 		drop_reason = psp_twsk_rx_policy_check(inet_twsk(sk), skb);
-		if (drop_reason)
-			break;
+		if (drop_reason) {
+			inet_twsk_put(inet_twsk(sk));
+			goto discard_it;
+		}
 	}
 		/* to ACK */
 		fallthrough;

net/ipv6/tcp_ipv6.c

@@ -1977,8 +1977,10 @@ INDIRECT_CALLABLE_SCOPE int tcp_v6_rcv(struct sk_buff *skb)
 		}
 
 		drop_reason = psp_twsk_rx_policy_check(inet_twsk(sk), skb);
-		if (drop_reason)
-			break;
+		if (drop_reason) {
+			inet_twsk_put(inet_twsk(sk));
+			goto discard_it;
+		}
 	}
 		/* to ACK */
 		fallthrough;