The output from tcp debug sockets was incomplete. After detach tp

was NULL and nothing was traced.  So save the old tcpcb and use
that to retrieve some information.  Note that otb may be freed and
must not be dereferenced.  Use a heuristic for cases where the
address family is in the IP header but not provided in the PCB.
OK visa@

1 files changed, 11 insertions, 33 deletions

diff --git a/sys/netinet/tcp_input.c b/sys/netinet/tcp_input.c
index a5fd6f7d7e4..25795a1155c 100644
--- a/sys/netinet/tcp_input.c
+++ b/sys/netinet/tcp_input.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: tcp_input.c,v 1.355 2018/05/08 15:10:33 bluhm Exp $	*/
+/*	$OpenBSD: tcp_input.c,v 1.356 2018/06/11 07:40:26 bluhm Exp $	*/
 /*	$NetBSD: tcp_input.c,v 1.23 1996/02/13 23:43:44 christos Exp $	*/
 
 /*
@@ -366,12 +366,13 @@ tcp_input(struct mbuf **mp, int *offp, int proto, int af)
 	u_int8_t *optp = NULL;
 	int optlen = 0;
 	int tlen, off;
-	struct tcpcb *tp = NULL;
+	struct tcpcb *otp = NULL, *tp = NULL;
 	int tiflags;
 	struct socket *so = NULL;
 	int todrop, acked, ourfinisacked;
 	int hdroptlen = 0;
-	short ostate = 0;
+	short ostate;
+	caddr_t saveti;
 	tcp_seq iss, *reuse = NULL;
 	u_long tiwin;
 	struct tcp_opt_info opti;
@@ -635,20 +636,21 @@ findpcb:
 			dst.sin6.sin6_port = th->th_dport;
 			break;
 #endif /* INET6 */
-		default:
-			goto badsyn;	/*sanity*/
 		}
 
 		if (so->so_options & SO_DEBUG) {
+			otp = tp;
 			ostate = tp->t_state;
 			switch (af) {
 #ifdef INET6
 			case AF_INET6:
+				saveti = (caddr_t) &tcp_saveti6;
 				memcpy(&tcp_saveti6.ti6_i, ip6, sizeof(*ip6));
 				memcpy(&tcp_saveti6.ti6_t, th, sizeof(*th));
 				break;
 #endif
 			case AF_INET:
+				saveti = (caddr_t) &tcp_saveti;
 				memcpy(&tcp_saveti.ti_i, ip, sizeof(*ip));
 				memcpy(&tcp_saveti.ti_t, th, sizeof(*th));
 				break;
@@ -2001,20 +2003,8 @@ dodata:							/* XXX */
 			break;
 		}
 	}
-	if (so->so_options & SO_DEBUG) {
-		switch (tp->pf) {
-#ifdef INET6
-		case PF_INET6:
-			tcp_trace(TA_INPUT, ostate, tp, (caddr_t) &tcp_saveti6,
-			    0, tlen);
-			break;
-#endif /* INET6 */
-		case PF_INET:
-			tcp_trace(TA_INPUT, ostate, tp, (caddr_t) &tcp_saveti,
-			    0, tlen);
-			break;
-		}
-	}
+	if (otp)
+		tcp_trace(TA_INPUT, ostate, tp, otp, saveti, 0, tlen);
 
 	/*
 	 * Return any desired output.
@@ -2089,20 +2079,8 @@ drop:
 	/*
 	 * Drop space held by incoming segment and return.
 	 */
-	if (tp && (tp->t_inpcb->inp_socket->so_options & SO_DEBUG)) {
-		switch (tp->pf) {
-#ifdef INET6
-		case PF_INET6:
-			tcp_trace(TA_DROP, ostate, tp, (caddr_t) &tcp_saveti6,
-			    0, tlen);
-			break;
-#endif /* INET6 */
-		case PF_INET:
-			tcp_trace(TA_DROP, ostate, tp, (caddr_t) &tcp_saveti,
-			    0, tlen);
-			break;
-		}
-	}
+	if (otp)
+		tcp_trace(TA_DROP, ostate, tp, otp, saveti, 0, tlen);
 
 	m_freem(m);
 	return IPPROTO_DONE;