diff --git a/sys/netinet/in_pcb.h b/sys/netinet/in_pcb.h
--- a/sys/netinet/in_pcb.h
+++ b/sys/netinet/in_pcb.h
@@ -670,7 +670,6 @@
 	    bool);
 int	in_pcbconnect_setup(struct inpcb *, struct sockaddr_in *, in_addr_t *,
 	    u_short *, in_addr_t *, u_short *, struct ucred *);
-void	in_pcbdetach(struct inpcb *);
 void	in_pcbdisconnect(struct inpcb *);
 void	in_pcbdrop(struct inpcb *);
 void	in_pcbfree(struct inpcb *);
diff --git a/sys/netinet/in_pcb.c b/sys/netinet/in_pcb.c
--- a/sys/netinet/in_pcb.c
+++ b/sys/netinet/in_pcb.c
@@ -1403,26 +1403,6 @@
 }
 #endif /* INET */
 
-/*
- * in_pcbdetach() is responsibe for disassociating a socket from an inpcb.
- * For most protocols, this will be invoked immediately prior to calling
- * in_pcbfree().  However, with TCP the inpcb may significantly outlive the
- * socket, in which case in_pcbfree() is deferred.
- */
-void
-in_pcbdetach(struct inpcb *inp)
-{
-
-	KASSERT(inp->inp_socket != NULL, ("%s: inp_socket == NULL", __func__));
-
-#ifdef RATELIMIT
-	if (inp->inp_snd_tag != NULL)
-		in_pcbdetach_txrtlmt(inp);
-#endif
-	inp->inp_socket->so_pcb = NULL;
-	inp->inp_socket = NULL;
-}
-
 /*
  * inpcb hash lookups are protected by SMR section.
  *
@@ -1733,10 +1713,23 @@
 #endif
 
 	INP_WLOCK_ASSERT(inp);
-	KASSERT(inp->inp_socket == NULL, ("%s: inp_socket != NULL", __func__));
+	KASSERT(inp->inp_socket != NULL, ("%s: inp_socket == NULL", __func__));
 	KASSERT((inp->inp_flags & INP_FREED) == 0,
 	    ("%s: called twice for pcb %p", __func__, inp));
 
+	/*
+	 * in_pcblookup_local() and in6_pcblookup_local() may return an inpcb
+	 * from the hash without acquiring inpcb lock, they rely on the hash
+	 * lock, thus in_pcbremhash() should be the first action.
+	 */
+	if (inp->inp_flags & INP_INHASHLIST)
+		in_pcbremhash(inp);
+#ifdef RATELIMIT
+	if (inp->inp_snd_tag != NULL)
+		in_pcbdetach_txrtlmt(inp);
+#endif
+	inp->inp_socket->so_pcb = NULL;
+	inp->inp_socket = NULL;
 	inp->inp_flags |= INP_FREED;
 	INP_INFO_WLOCK(pcbinfo);
 	inp->inp_gencnt = ++pcbinfo->ipi_gencnt;
@@ -1744,9 +1737,6 @@
 	CK_LIST_REMOVE(inp, inp_list);
 	INP_INFO_WUNLOCK(pcbinfo);
 
-	if (inp->inp_flags & INP_INHASHLIST)
-		in_pcbremhash(inp);
-
 	RO_INVALIDATE_CACHE(&inp->inp_route);
 #ifdef MAC
 	mac_inpcb_destroy(inp);
diff --git a/sys/netinet/raw_ip.c b/sys/netinet/raw_ip.c
--- a/sys/netinet/raw_ip.c
+++ b/sys/netinet/raw_ip.c
@@ -860,7 +860,6 @@
 		ip_rsvp_force_done(so);
 	if (so == V_ip_rsvpd)
 		ip_rsvp_done();
-	in_pcbdetach(inp);
 	in_pcbfree(inp);
 }
 
diff --git a/sys/netinet/tcp_syncache.c b/sys/netinet/tcp_syncache.c
--- a/sys/netinet/tcp_syncache.c
+++ b/sys/netinet/tcp_syncache.c
@@ -803,7 +803,6 @@
 	}
 	inp = sotoinpcb(so);
 	if ((tp = tcp_newtcpcb(inp)) == NULL) {
-		in_pcbdetach(inp);
 		in_pcbfree(inp);
 		sodealloc(so);
 		goto allocfail;
@@ -1051,7 +1050,6 @@
 	return (NULL);
 
 abort:
-	in_pcbdetach(inp);
 	in_pcbfree(inp);
 	sodealloc(so);
 	if ((s = tcp_log_addrs(&sc->sc_inc, NULL, NULL, NULL))) {
diff --git a/sys/netinet/tcp_usrreq.c b/sys/netinet/tcp_usrreq.c
--- a/sys/netinet/tcp_usrreq.c
+++ b/sys/netinet/tcp_usrreq.c
@@ -175,7 +175,6 @@
 	tp = tcp_newtcpcb(inp);
 	if (tp == NULL) {
 		error = ENOBUFS;
-		in_pcbdetach(inp);
 		in_pcbfree(inp);
 		goto out;
 	}
@@ -213,7 +212,6 @@
 	    ("%s: inp %p not dropped or embryonic", __func__, inp));
 
 	tcp_discardcb(tp);
-	in_pcbdetach(inp);
 	in_pcbfree(inp);
 }
 
diff --git a/sys/netinet/udp_usrreq.c b/sys/netinet/udp_usrreq.c
--- a/sys/netinet/udp_usrreq.c
+++ b/sys/netinet/udp_usrreq.c
@@ -1641,7 +1641,6 @@
 	KASSERT(inp->inp_faddr.s_addr == INADDR_ANY,
 	    ("udp_detach: not disconnected"));
 	INP_WLOCK(inp);
-	in_pcbdetach(inp);
 	in_pcbfree(inp);
 }
 
diff --git a/sys/netinet6/raw_ip6.c b/sys/netinet6/raw_ip6.c
--- a/sys/netinet6/raw_ip6.c
+++ b/sys/netinet6/raw_ip6.c
@@ -687,7 +687,6 @@
 	/* xxx: RSVP */
 	INP_WLOCK(inp);
 	free(inp->in6p_icmp6filt, M_PCB);
-	in_pcbdetach(inp);
 	in_pcbfree(inp);
 }
 
diff --git a/sys/netinet6/udp6_usrreq.c b/sys/netinet6/udp6_usrreq.c
--- a/sys/netinet6/udp6_usrreq.c
+++ b/sys/netinet6/udp6_usrreq.c
@@ -1201,7 +1201,6 @@
 	KASSERT(inp != NULL, ("udp6_detach: inp == NULL"));
 
 	INP_WLOCK(inp);
-	in_pcbdetach(inp);
 	in_pcbfree(inp);
 }