getifaddrs() can return entries where ifa_addr is NULL. Check for this

before accessing anything in ifa_addr.
ok claudio@

4 files changed, 19 insertions, 12 deletions

diff --git a/lib/libc/rpc/get_myaddress.c b/lib/libc/rpc/get_myaddress.c
index d0ac78f796e..99c0dabee70 100644
--- a/lib/libc/rpc/get_myaddress.c
+++ b/lib/libc/rpc/get_myaddress.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: get_myaddress.c,v 1.15 2015/09/13 15:36:56 guenther Exp $ */
+/*	$OpenBSD: get_myaddress.c,v 1.16 2020/12/30 18:56:35 benno Exp $ */
 
 /*
  * Copyright (c) 2010, Oracle America, Inc.
@@ -67,6 +67,7 @@ get_myaddress(struct sockaddr_in *addr)
   again:
 	for (ifa = ifap; ifa; ifa = ifa->ifa_next) {
 		if ((ifa->ifa_flags & IFF_UP) &&
+		    ifa->ifa_addr != NULL &&
 		    ifa->ifa_addr->sa_family == AF_INET &&
 		    (loopback == 1 && (ifa->ifa_flags & IFF_LOOPBACK))) {
 			*addr = *((struct sockaddr_in *)ifa->ifa_addr);
diff --git a/lib/libc/rpc/pmap_rmt.c b/lib/libc/rpc/pmap_rmt.c
index 097999b5ae6..7d971f690a1 100644
--- a/lib/libc/rpc/pmap_rmt.c
+++ b/lib/libc/rpc/pmap_rmt.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: pmap_rmt.c,v 1.35 2019/06/28 13:32:42 deraadt Exp $ */
+/*	$OpenBSD: pmap_rmt.c,v 1.36 2020/12/30 18:56:35 benno Exp $ */
 
 /*
  * Copyright (c) 2010, Oracle America, Inc.
@@ -163,7 +163,8 @@ newgetbroadcastnets(struct in_addr **addrsp)
 		return 0;
 
 	for (ifa = ifap; ifa; ifa = ifa->ifa_next) {
-		if (ifa->ifa_addr->sa_family != AF_INET)
+		if (ifa->ifa_addr == NULL ||
+		    ifa->ifa_addr->sa_family != AF_INET)
 			continue;
 		if ((ifa->ifa_flags & IFF_BROADCAST) &&
 		    (ifa->ifa_flags & IFF_UP) &&
@@ -180,7 +181,8 @@ newgetbroadcastnets(struct in_addr **addrsp)
 	}
 
 	for (ifa = ifap; ifa; ifa = ifa->ifa_next) {
-		if (ifa->ifa_addr->sa_family != AF_INET)
+		if (ifa->ifa_addr == NULL ||
+		    ifa->ifa_addr->sa_family != AF_INET)
 			continue;
 		if ((ifa->ifa_flags & IFF_BROADCAST) &&
 		    (ifa->ifa_flags & IFF_UP) &&
diff --git a/regress/sys/netinet/in_pcbbind/runtest.c b/regress/sys/netinet/in_pcbbind/runtest.c
index e26d2832dce..2842a2c7b7d 100644
--- a/regress/sys/netinet/in_pcbbind/runtest.c
+++ b/regress/sys/netinet/in_pcbbind/runtest.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: runtest.c,v 1.5 2017/07/06 13:20:54 bluhm Exp $ */
+/* $OpenBSD: runtest.c,v 1.6 2020/12/30 18:56:56 benno Exp $ */
 /*
  * Copyright (c) 2015 Vincent Gross <vincent.gross@kilob.yt>
  *
@@ -415,7 +415,8 @@ main(int argc, char *argv[])
 			err(2, "getifaddrs()");
 		curifa = ifap;
 		while (curifa) {
-			if (memcmp(curifa->ifa_addr,
+			if (curifa->ifa_addr != NULL &&
+			    memcmp(curifa->ifa_addr,
 			    mifa->ai_addr,
 			    mifa->ai_addrlen) == 0)
 				break;
diff --git a/sbin/ifconfig/ifconfig.c b/sbin/ifconfig/ifconfig.c
index 3799cc3a8e9..3d8f6b3b9c2 100644
--- a/sbin/ifconfig/ifconfig.c
+++ b/sbin/ifconfig/ifconfig.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: ifconfig.c,v 1.430 2020/11/06 21:24:47 kn Exp $	*/
+/*	$OpenBSD: ifconfig.c,v 1.431 2020/12/30 18:57:28 benno Exp $	*/
 /*	$NetBSD: ifconfig.c,v 1.40 1997/10/01 02:19:43 enami Exp $	*/
 
 /*
@@ -1180,12 +1180,13 @@ printif(char *name, int ifaliases)
 			}
 		}
 		/* quickhack: sizeof(ifr) < sizeof(ifr6) */
-		if (ifa->ifa_addr->sa_family == AF_INET6) {
+		if (ifa->ifa_addr != NULL &&
+		    ifa->ifa_addr->sa_family == AF_INET6) {
 			memset(&ifr6, 0, sizeof(ifr6));
 			memcpy(&ifr6.ifr_addr, ifa->ifa_addr,
 			    MINIMUM(sizeof(ifr6.ifr_addr), ifa->ifa_addr->sa_len));
 			ifrp = (struct ifreq *)&ifr6;
-		} else {
+		} else if (ifa->ifa_addr != NULL) {
 			memset(&ifr, 0, sizeof(ifr));
 			memcpy(&ifr.ifr_addr, ifa->ifa_addr,
 			    MINIMUM(sizeof(ifr.ifr_addr), ifa->ifa_addr->sa_len));
@@ -1194,7 +1195,8 @@ printif(char *name, int ifaliases)
 		strlcpy(ifname, ifa->ifa_name, sizeof(ifname));
 		strlcpy(ifrp->ifr_name, ifa->ifa_name, sizeof(ifrp->ifr_name));
 
-		if (ifa->ifa_addr->sa_family == AF_LINK) {
+		if (ifa->ifa_addr != NULL &&
+		    ifa->ifa_addr->sa_family == AF_LINK) {
 			namep = ifa->ifa_name;
 			if (getinfo(ifrp, 0) < 0)
 				continue;
@@ -1209,8 +1211,9 @@ printif(char *name, int ifaliases)
 		if (!namep || !strcmp(namep, ifa->ifa_name)) {
 			const struct afswtch *p;
 
-			if (ifa->ifa_addr->sa_family == AF_INET &&
-			    ifaliases == 0 && noinet == 0)
+			if (ifa->ifa_addr == NULL ||
+			    (ifa->ifa_addr->sa_family == AF_INET &&
+			    ifaliases == 0 && noinet == 0))
 				continue;
 			if ((p = afp) != NULL) {
 				if (ifa->ifa_addr->sa_family == p->af_af)