bad sysctl(), malloc(0), and memory leaks fixes

2 files changed, 45 insertions, 31 deletions

diff --git a/sbin/route/route.c b/sbin/route/route.c
index ec101635989..80f0eb306c9 100644
--- a/sbin/route/route.c
+++ b/sbin/route/route.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: route.c,v 1.26 1997/12/12 09:06:08 deraadt Exp $	*/
+/*	$OpenBSD: route.c,v 1.27 1998/09/21 08:31:46 deraadt Exp $	*/
 /*	$NetBSD: route.c,v 1.16 1996/04/15 18:27:05 cgd Exp $	*/
 
 /*
@@ -44,7 +44,7 @@ static char copyright[] =
 #if 0
 static char sccsid[] = "@(#)route.c	8.3 (Berkeley) 3/19/94";
 #else
-static char rcsid[] = "$OpenBSD: route.c,v 1.26 1997/12/12 09:06:08 deraadt Exp $";
+static char rcsid[] = "$OpenBSD: route.c,v 1.27 1998/09/21 08:31:46 deraadt Exp $";
 #endif
 #endif /* not lint */
 
@@ -230,7 +230,7 @@ flushroutes(argc, argv)
 {
 	size_t needed;
 	int mib[6], rlen, seqno;
-	char *buf, *next, *lim;
+	char *buf = NULL, *next, *lim;
 	register struct rt_msghdr *rtm;
 
 	if (uid) {
@@ -277,16 +277,21 @@ bad:			usage(*argv);
 	mib[5] = 0;		/* no flags */
 	if (sysctl(mib, 6, NULL, &needed, NULL, 0) < 0)
 		quit("route-sysctl-estimate");
-	if ((buf = malloc(needed)) == NULL)
-		quit("malloc");
-	if (sysctl(mib, 6, buf, &needed, NULL, 0) < 0)
-		quit("actual retrieval of routing table");
-	lim = buf + needed;
+	if (needed) {
+		if ((buf = malloc(needed)) == NULL)
+			quit("malloc");
+		if (sysctl(mib, 6, buf, &needed, NULL, 0) < 0)
+			quit("actual retrieval of routing table");
+		lim = buf + needed;
+	}
 	if (verbose) {
 		(void) printf("Examining routing table from sysctl\n");
 		 if (af)
 			printf("(address family %s)\n", (*argv + 1));
 	}
+	if (buf == NULL)
+		return;
+
 	seqno = 0;		/* ??? */
 	for (next = buf; next < lim; next += rtm->rtm_msglen) {
 		rtm = (struct rt_msghdr *)next;
@@ -326,6 +331,7 @@ bad:			usage(*argv);
 			(void) printf("done\n");
 		}
 	}
+	free(buf);
 }
 
 static char hexlist[] = "0123456789abcdef";
@@ -1074,7 +1080,7 @@ interfaces()
 {
 	size_t needed;
 	int mib[6];
-	char *buf, *lim, *next;
+	char *buf = NULL, *lim, *next;
 	register struct rt_msghdr *rtm;
 
 	mib[0] = CTL_NET;
@@ -1085,14 +1091,17 @@ interfaces()
 	mib[5] = 0;		/* no flags */
 	if (sysctl(mib, 6, NULL, &needed, NULL, 0) < 0)
 		quit("route-sysctl-estimate");
-	if ((buf = malloc(needed)) == NULL)
-		quit("malloc");
-	if (sysctl(mib, 6, buf, &needed, NULL, 0) < 0)
-		quit("actual retrieval of interface table");
-	lim = buf + needed;
-	for (next = buf; next < lim; next += rtm->rtm_msglen) {
-		rtm = (struct rt_msghdr *)next;
-		print_rtmsg(rtm, rtm->rtm_msglen);
+	if (needed) {
+		if ((buf = malloc(needed)) == NULL)
+			quit("malloc");
+		if (sysctl(mib, 6, buf, &needed, NULL, 0) < 0)
+			quit("actual retrieval of interface table");
+		lim = buf + needed;
+		for (next = buf; next < lim; next += rtm->rtm_msglen) {
+			rtm = (struct rt_msghdr *)next;
+			print_rtmsg(rtm, rtm->rtm_msglen);
+		}
+		free(buf);
 	}
 }
 
diff --git a/sbin/route/show.c b/sbin/route/show.c
index 527dd1fa5d6..386ded5aa6e 100644
--- a/sbin/route/show.c
+++ b/sbin/route/show.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: show.c,v 1.6 1998/07/09 01:32:12 deraadt Exp $	*/
+/*	$OpenBSD: show.c,v 1.7 1998/09/21 08:31:46 deraadt Exp $	*/
 /*	$NetBSD: show.c,v 1.1 1996/11/15 18:01:41 gwr Exp $	*/
 
 /*
@@ -38,7 +38,7 @@
 #if 0
 static char sccsid[] = "from: @(#)route.c	8.3 (Berkeley) 3/9/94";
 #else
-static char *rcsid = "$OpenBSD: show.c,v 1.6 1998/07/09 01:32:12 deraadt Exp $";
+static char *rcsid = "$OpenBSD: show.c,v 1.7 1998/09/21 08:31:46 deraadt Exp $";
 #endif
 #endif /* not lint */
 
@@ -112,7 +112,7 @@ show(argc, argv)
 	char **argv;
 {
 	register struct rt_msghdr *rtm;
-	char *buf, *next, *lim;
+	char *buf = NULL, *next, *lim;
 	size_t needed;
 	int mib[6];
 
@@ -126,21 +126,26 @@ show(argc, argv)
 		perror("route-sysctl-estimate");
 		exit(1);
 	}
-	if ((buf = malloc(needed)) == 0) {
-		printf("out of space\n");
-		exit(1);
-	}
-	if (sysctl(mib, 6, buf, &needed, NULL, 0) < 0) {
-		perror("sysctl of routing table");
-		exit(1);
+	if (needed > 0) {
+		if ((buf = malloc(needed)) == 0) {
+			printf("out of space\n");
+			exit(1);
+		}
+		if (sysctl(mib, 6, buf, &needed, NULL, 0) < 0) {
+			perror("sysctl of routing table");
+			exit(1);
+		}
+		lim  = buf + needed;
 	}
-	lim  = buf + needed;
 
 	printf("Routing tables\n");
 
-	for (next = buf; next < lim; next += rtm->rtm_msglen) {
-		rtm = (struct rt_msghdr *)next;
-		p_rtentry(rtm);
+	if (buf) {
+		for (next = buf; next < lim; next += rtm->rtm_msglen) {
+			rtm = (struct rt_msghdr *)next;
+			p_rtentry(rtm);
+		}
+		free(buf);
 	}
 }