Cache so_cred as inp_cred in the inpcb.

This means that inp_cred is always there, even after the socket
has gone away. It also means that it is constant for the lifetime
of the inp.
Both facts lead to simpler code and possibly less locking.

Suggested by:	rwatson
Reviewed by:	rwatson
MFC after:	6 weeks
X-MFC Note:	use a inp_pspare for inp_cred

9 files changed, 43 insertions, 55 deletions

diff --git a/sys/contrib/pf/net/pf.c b/sys/contrib/pf/net/pf.c
index c1011be..7ac43da 100644
--- a/sys/contrib/pf/net/pf.c
+++ b/sys/contrib/pf/net/pf.c
@@ -2941,13 +2941,9 @@ pf_socket_lookup(int direction, struct pf_pdesc *pd)
 #ifdef __FreeBSD__
 	if (inp_arg != NULL) {
 		INP_LOCK_ASSERT(inp_arg);
-		if (inp_arg->inp_socket) {
-			pd->lookup.uid = inp_arg->inp_socket->so_cred->cr_uid;
-			pd->lookup.gid =
-			    inp_arg->inp_socket->so_cred->cr_groups[0];
-			return (1);
-		} else
-			return (-1);
+		pd->lookup.uid = inp_arg->inp_cred->cr_uid;
+		pd->lookup.gid = inp_arg->inp_cred->cr_groups[0];
+		return (1);
 	}
 #endif
 	switch (pd->proto) {
@@ -3043,15 +3039,9 @@ pf_socket_lookup(int direction, struct pf_pdesc *pd)
 		return (-1);
 	}
 #ifdef __FreeBSD__
-	INP_RLOCK(inp);
+	pd->lookup.uid = inp->inp_cred->cr_uid;
+	pd->lookup.gid = inp->inp_cred->cr_groups[0];
 	INP_INFO_RUNLOCK(pi);
-	if ((inp->inp_socket == NULL) || (inp->inp_socket->so_cred == NULL)) {
-		INP_RUNLOCK(inp);
-		return (-1);
-	}
-	pd->lookup.uid = inp->inp_socket->so_cred->cr_uid;
-	pd->lookup.gid = inp->inp_socket->so_cred->cr_groups[0];
-	INP_RUNLOCK(inp);
 #else
 	pd->lookup.uid = inp->inp_socket->so_euid;
 	pd->lookup.gid = inp->inp_socket->so_egid;
diff --git a/sys/netinet/in_pcb.c b/sys/netinet/in_pcb.c
index ea98a6f..d76ed16 100644
--- a/sys/netinet/in_pcb.c
+++ b/sys/netinet/in_pcb.c
@@ -197,6 +197,7 @@ in_pcballoc(struct socket *so, struct inpcbinfo *pcbinfo)
 	bzero(inp, inp_zero_size);
 	inp->inp_pcbinfo = pcbinfo;
 	inp->inp_socket = so;
+	inp->inp_cred = crhold(so->so_cred);
 	inp->inp_inc.inc_fibnum = so->so_fibnum;
 #ifdef MAC
 	error = mac_inpcb_init(inp, M_NOWAIT);
@@ -235,8 +236,10 @@ in_pcballoc(struct socket *so, struct inpcbinfo *pcbinfo)
 
 #if defined(IPSEC) || defined(MAC)
 out:
-	if (error != 0)
+	if (error != 0) {
+		crfree(inp->inp_cred);
 		uma_zfree(pcbinfo->ipi_zone, inp);
+	}
 #endif
 	return (error);
 }
@@ -357,7 +360,7 @@ in_pcbbind_setup(struct inpcb *inp, struct sockaddr *nam, in_addr_t *laddrp,
 			if (jailed(cred))
 				prison = 1;
 			if (!IN_MULTICAST(ntohl(sin->sin_addr.s_addr)) &&
-			    priv_check_cred(so->so_cred,
+			    priv_check_cred(inp->inp_cred,
 			    PRIV_NETINET_REUSEPORT, 0) != 0) {
 				t = in_pcblookup_local(pcbinfo, sin->sin_addr,
 				    lport, prison ? 0 : INPLOOKUP_WILDCARD,
@@ -374,8 +377,8 @@ in_pcbbind_setup(struct inpcb *inp, struct sockaddr *nam, in_addr_t *laddrp,
 				     ntohl(t->inp_laddr.s_addr) != INADDR_ANY ||
 				     (t->inp_socket->so_options &
 					 SO_REUSEPORT) == 0) &&
-				    (so->so_cred->cr_uid !=
-				     t->inp_socket->so_cred->cr_uid))
+				    (inp->inp_cred->cr_uid !=
+				     t->inp_cred->cr_uid))
 					return (EADDRINUSE);
 			}
 			if (prison && prison_ip(cred, 0, &sin->sin_addr.s_addr))
@@ -901,6 +904,7 @@ in_pcbfree(struct inpcb *inp)
 	if (inp->inp_moptions != NULL)
 		inp_freemoptions(inp->inp_moptions);
 	inp->inp_vflag = 0;
+	crfree(inp->inp_cred);
 
 #ifdef MAC
 	mac_inpcb_destroy(inp);
diff --git a/sys/netinet/in_pcb.h b/sys/netinet/in_pcb.h
index 857d007..b393c18 100644
--- a/sys/netinet/in_pcb.h
+++ b/sys/netinet/in_pcb.h
@@ -153,6 +153,7 @@ struct inpcb {
 	void	*inp_ppcb;		/* (i) pointer to per-protocol pcb */
 	struct	inpcbinfo *inp_pcbinfo;	/* (c) PCB list info */
 	struct	socket *inp_socket;	/* (i)  back pointer to socket */
+	struct	ucred	*inp_cred;	/* (c) cache of socket cred */
 
 	u_int32_t	inp_flow;	/* (i) IPv6 flow information */
 	int	inp_flags;		/* (i) generic IP/datagram flags */
diff --git a/sys/netinet/ip_fw2.c b/sys/netinet/ip_fw2.c
index 861f9e9..ab4fbb6 100644
--- a/sys/netinet/ip_fw2.c
+++ b/sys/netinet/ip_fw2.c
@@ -1977,15 +1977,11 @@ fill_ugid_cache(struct inpcb *inp, struct ip_fw_ugid *ugp)
 {
 	struct ucred *cr;
 
-	if (inp->inp_socket != NULL) {
-		cr = inp->inp_socket->so_cred;
-		ugp->fw_prid = jailed(cr) ?
-		    cr->cr_prison->pr_id : -1;
-		ugp->fw_uid = cr->cr_uid;
-		ugp->fw_ngroups = cr->cr_ngroups;
-		bcopy(cr->cr_groups, ugp->fw_groups,
-		    sizeof(ugp->fw_groups));
-	}
+	cr = inp->inp_cred;
+	ugp->fw_prid = jailed(cr) ? cr->cr_prison->pr_id : -1;
+	ugp->fw_uid = cr->cr_uid;
+	ugp->fw_ngroups = cr->cr_ngroups;
+	bcopy(cr->cr_groups, ugp->fw_groups, sizeof(ugp->fw_groups));
 }
 
 static int
@@ -2042,12 +2038,8 @@ check_uidgid(ipfw_insn_u32 *insn, int proto, struct ifnet *oif,
 				dst_ip, htons(dst_port),
 				wildcard, NULL);
 		if (pcb != NULL) {
-			INP_RLOCK(pcb);
-			if (pcb->inp_socket != NULL) {
-				fill_ugid_cache(pcb, ugp);
-				*ugid_lookupp = 1;
-			}
-			INP_RUNLOCK(pcb);
+			fill_ugid_cache(pcb, ugp);
+			*ugid_lookupp = 1;
 		}
 		INP_INFO_RUNLOCK(pi);
 		if (*ugid_lookupp == 0) {
diff --git a/sys/netinet/raw_ip.c b/sys/netinet/raw_ip.c
index c6bca32..0300492 100644
--- a/sys/netinet/raw_ip.c
+++ b/sys/netinet/raw_ip.c
@@ -261,6 +261,7 @@ rip_input(struct mbuf *m, int off)
 		if (inp->inp_ip_p != proto)
 			continue;
 #ifdef INET6
+		/* XXX inp locking */
 		if ((inp->inp_vflag & INP_IPV4) == 0)
 			continue;
 #endif
@@ -268,11 +269,9 @@ rip_input(struct mbuf *m, int off)
 			continue;
 		if (inp->inp_faddr.s_addr != ip->ip_src.s_addr)
 			continue;
-		INP_RLOCK(inp);
-		if (jailed(inp->inp_socket->so_cred) &&
-		    (htonl(prison_getip(inp->inp_socket->so_cred)) !=
+		if (jailed(inp->inp_cred) &&
+		    (htonl(prison_getip(inp->inp_cred)) !=
 		    ip->ip_dst.s_addr)) {
-			INP_RUNLOCK(inp);
 			continue;
 		}
 		if (last) {
@@ -284,12 +283,14 @@ rip_input(struct mbuf *m, int off)
 			/* XXX count dropped packet */
 			INP_RUNLOCK(last);
 		}
+		INP_RLOCK(inp);
 		last = inp;
 	}
 	LIST_FOREACH(inp, &V_ripcbinfo.ipi_hashbase[0], inp_hash) {
 		if (inp->inp_ip_p && inp->inp_ip_p != proto)
 			continue;
 #ifdef INET6
+		/* XXX inp locking */
 		if ((inp->inp_vflag & INP_IPV4) == 0)
 			continue;
 #endif
@@ -299,9 +300,8 @@ rip_input(struct mbuf *m, int off)
 		if (inp->inp_faddr.s_addr &&
 		    inp->inp_faddr.s_addr != ip->ip_src.s_addr)
 			continue;
-		INP_RLOCK(inp);
-		if (jailed(inp->inp_socket->so_cred) &&
-		    (htonl(prison_getip(inp->inp_socket->so_cred)) !=
+		if (jailed(inp->inp_cred) &&
+		    (htonl(prison_getip(inp->inp_cred)) !=
 		    ip->ip_dst.s_addr)) {
 			INP_RUNLOCK(inp);
 			continue;
@@ -315,6 +315,7 @@ rip_input(struct mbuf *m, int off)
 			/* XXX count dropped packet */
 			INP_RUNLOCK(last);
 		}
+		INP_RLOCK(inp);
 		last = inp;
 	}
 	INP_INFO_RUNLOCK(&V_ripcbinfo);
@@ -365,9 +366,9 @@ rip_output(struct mbuf *m, struct socket *so, u_long dst)
 			ip->ip_off = 0;
 		ip->ip_p = inp->inp_ip_p;
 		ip->ip_len = m->m_pkthdr.len;
-		if (jailed(inp->inp_socket->so_cred))
+		if (jailed(inp->inp_cred))
 			ip->ip_src.s_addr =
-			    htonl(prison_getip(inp->inp_socket->so_cred));
+			    htonl(prison_getip(inp->inp_cred));
 		else
 			ip->ip_src = inp->inp_laddr;
 		ip->ip_dst.s_addr = dst;
@@ -379,9 +380,9 @@ rip_output(struct mbuf *m, struct socket *so, u_long dst)
 		}
 		INP_RLOCK(inp);
 		ip = mtod(m, struct ip *);
-		if (jailed(inp->inp_socket->so_cred)) {
+		if (jailed(inp->inp_cred)) {
 			if (ip->ip_src.s_addr !=
-			    htonl(prison_getip(inp->inp_socket->so_cred))) {
+			    htonl(prison_getip(inp->inp_cred))) {
 				INP_RUNLOCK(inp);
 				m_freem(m);
 				return (EPERM);
diff --git a/sys/netinet/tcp_subr.c b/sys/netinet/tcp_subr.c
index f94e290..be9daae 100644
--- a/sys/netinet/tcp_subr.c
+++ b/sys/netinet/tcp_subr.c
@@ -1107,7 +1107,7 @@ tcp_getcred(SYSCTL_HANDLER_ARGS)
 			error = cr_canseesocket(req->td->td_ucred,
 			    inp->inp_socket);
 		if (error == 0)
-			cru2x(inp->inp_socket->so_cred, &xuc);
+			cru2x(inp->inp_cred, &xuc);
 		INP_RUNLOCK(inp);
 	} else {
 		INP_INFO_RUNLOCK(&V_tcbinfo);
@@ -1171,7 +1171,7 @@ tcp6_getcred(SYSCTL_HANDLER_ARGS)
 			error = cr_canseesocket(req->td->td_ucred,
 			    inp->inp_socket);
 		if (error == 0)
-			cru2x(inp->inp_socket->so_cred, &xuc);
+			cru2x(inp->inp_cred, &xuc);
 		INP_RUNLOCK(inp);
 	} else {
 		INP_INFO_RUNLOCK(&V_tcbinfo);
diff --git a/sys/netinet/udp_usrreq.c b/sys/netinet/udp_usrreq.c
index f33b760..b5b9c55 100644
--- a/sys/netinet/udp_usrreq.c
+++ b/sys/netinet/udp_usrreq.c
@@ -761,7 +761,7 @@ udp_getcred(SYSCTL_HANDLER_ARGS)
 			error = cr_canseesocket(req->td->td_ucred,
 			    inp->inp_socket);
 		if (error == 0)
-			cru2x(inp->inp_socket->so_cred, &xuc);
+			cru2x(inp->inp_cred, &xuc);
 		INP_RUNLOCK(inp);
 	} else {
 		INP_INFO_RUNLOCK(&V_udbinfo);
diff --git a/sys/netinet6/in6_pcb.c b/sys/netinet6/in6_pcb.c
index 404335b..d241f1e 100644
--- a/sys/netinet6/in6_pcb.c
+++ b/sys/netinet6/in6_pcb.c
@@ -189,7 +189,7 @@ in6_pcbbind(register struct inpcb *inp, struct sockaddr *nam,
 			    0))
 				return (EACCES);
 			if (!IN6_IS_ADDR_MULTICAST(&sin6->sin6_addr) &&
-			    priv_check_cred(so->so_cred,
+			    priv_check_cred(inp->inp_cred,
 			    PRIV_NETINET_REUSEPORT, 0) != 0) {
 				t = in6_pcblookup_local(pcbinfo,
 				    &sin6->sin6_addr, lport,
@@ -201,8 +201,8 @@ in6_pcbbind(register struct inpcb *inp, struct sockaddr *nam,
 				    (!IN6_IS_ADDR_UNSPECIFIED(&sin6->sin6_addr) ||
 				     !IN6_IS_ADDR_UNSPECIFIED(&t->in6p_laddr) ||
 				     (t->inp_socket->so_options & SO_REUSEPORT)
-				      == 0) && (so->so_cred->cr_uid !=
-				     t->inp_socket->so_cred->cr_uid))
+				      == 0) && (inp->inp_cred->cr_uid !=
+				     t->inp_cred->cr_uid))
 					return (EADDRINUSE);
 				if ((inp->inp_flags & IN6P_IPV6_V6ONLY) == 0 &&
 				    IN6_IS_ADDR_UNSPECIFIED(&sin6->sin6_addr)) {
@@ -218,8 +218,8 @@ in6_pcbbind(register struct inpcb *inp, struct sockaddr *nam,
 					    (so->so_type != SOCK_STREAM ||
 					     ntohl(t->inp_faddr.s_addr) ==
 					      INADDR_ANY) &&
-					    (so->so_cred->cr_uid !=
-					     t->inp_socket->so_cred->cr_uid))
+					    (inp->inp_cred->cr_uid !=
+					     t->inp_cred->cr_uid))
 						return (EADDRINUSE);
 				}
 			}
@@ -323,7 +323,7 @@ in6_pcbladdr(register struct inpcb *inp, struct sockaddr *nam,
 	 */
 	*plocal_addr6 = in6_selectsrc(sin6, inp->in6p_outputopts,
 				      inp, NULL,
-				      inp->inp_socket->so_cred,
+				      inp->inp_cred,
 				      &ifp, &error);
 	if (ifp && scope_ambiguous &&
 	    (error = in6_setscope(&sin6->sin6_addr, ifp, NULL)) != 0) {
diff --git a/sys/netinet6/udp6_usrreq.c b/sys/netinet6/udp6_usrreq.c
index 5056ef1..f85fe58 100644
--- a/sys/netinet6/udp6_usrreq.c
+++ b/sys/netinet6/udp6_usrreq.c
@@ -466,7 +466,7 @@ udp6_getcred(SYSCTL_HANDLER_ARGS)
 			error = cr_canseesocket(req->td->td_ucred,
 			    inp->inp_socket);
 		if (error == 0)
-			cru2x(inp->inp_socket->so_cred, &xuc);
+			cru2x(inp->inp_cred, &xuc);
 		INP_RUNLOCK(inp);
 	} else {
 		INP_INFO_RUNLOCK(&V_udbinfo);