create realloc() loops around sysctl for array-based mibs, in programs

which want a "full" dump
ok dlg

5 files changed, 79 insertions, 52 deletions

diff --git a/usr.sbin/arp/arp.c b/usr.sbin/arp/arp.c
index 95e079cf7ff..56b8390f954 100644
--- a/usr.sbin/arp/arp.c
+++ b/usr.sbin/arp/arp.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: arp.c,v 1.51 2012/11/08 11:05:41 phessler Exp $ */
+/*	$OpenBSD: arp.c,v 1.52 2013/03/21 04:43:17 deraadt Exp $ */
 /*	$NetBSD: arp.c,v 1.12 1995/04/24 13:25:18 cgd Exp $ */
 
 /*
@@ -442,7 +442,7 @@ search(in_addr_t addr, void (*action)(struct sockaddr_dl *sdl,
 {
 	int mib[7];
 	size_t needed;
-	char *lim, *buf, *next;
+	char *lim, *buf = NULL, *next;
 	struct rt_msghdr *rtm;
 	struct sockaddr_inarp *sin;
 	struct sockaddr_dl *sdl;
@@ -454,15 +454,21 @@ search(in_addr_t addr, void (*action)(struct sockaddr_dl *sdl,
 	mib[4] = NET_RT_FLAGS;
 	mib[5] = RTF_LLINFO;
 	mib[6] = rdomain;
-	if (sysctl(mib, 7, NULL, &needed, NULL, 0) < 0)
-		err(1, "route-sysctl-estimate");
-	if (needed == 0)
-		return;
-	if ((buf = malloc(needed)) == NULL)
-		err(1, "malloc");
-	if (sysctl(mib, 7, buf, &needed, NULL, 0) < 0)
-		err(1, "actual retrieval of routing table");
-	lim = buf + needed;
+	while (1) {
+		if (sysctl(mib, 7, NULL, &needed, NULL, 0) == -1)
+			err(1, "route-sysctl-estimate");
+		if (needed == 0)
+			return;
+		if ((buf = realloc(buf, needed)) == NULL)
+			err(1, "malloc");
+		if (sysctl(mib, 7, buf, &needed, NULL, 0) == -1) {
+			if (errno == ENOMEM)
+				continue;
+			err(1, "actual retrieval of routing table");
+		}
+		lim = buf + needed;
+		break;
+	}
 	for (next = buf; next < lim; next += rtm->rtm_msglen) {
 		rtm = (struct rt_msghdr *)next;
 		if (rtm->rtm_version != RTM_VERSION)
diff --git a/usr.sbin/ndp/ndp.c b/usr.sbin/ndp/ndp.c
index 5fb2db7cd29..28aed85098b 100644
--- a/usr.sbin/ndp/ndp.c
+++ b/usr.sbin/ndp/ndp.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: ndp.c,v 1.46 2013/03/11 14:02:37 mpi Exp $	*/
+/*	$OpenBSD: ndp.c,v 1.47 2013/03/21 04:43:17 deraadt Exp $	*/
 /*	$KAME: ndp.c,v 1.101 2002/07/17 08:46:33 itojun Exp $	*/
 
 /*
@@ -544,7 +544,7 @@ dump(struct in6_addr *addr, int cflag)
 {
 	int mib[6];
 	size_t needed;
-	char *lim, *buf, *next;
+	char *lim, *buf = NULL, *next;
 	struct rt_msghdr *rtm;
 	struct sockaddr_in6 *sin;
 	struct sockaddr_dl *sdl;
@@ -569,16 +569,21 @@ again:;
 	mib[3] = AF_INET6;
 	mib[4] = NET_RT_FLAGS;
 	mib[5] = RTF_LLINFO;
-	if (sysctl(mib, 6, NULL, &needed, NULL, 0) < 0)
-		err(1, "sysctl(PF_ROUTE estimate)");
-	if (needed > 0) {
-		if ((buf = malloc(needed)) == NULL)
-			err(1, "malloc");
-		if (sysctl(mib, 6, buf, &needed, NULL, 0) < 0)
+	while (1) {
+		if (sysctl(mib, 6, NULL, &needed, NULL, 0) == -1)
+			err(1, "sysctl(PF_ROUTE estimate)");
+		if (needed == 0)
+			break;
+		if ((buf = realloc(buf, needed)) == NULL)
+			err(1, "realloc");
+		if (sysctl(mib, 6, buf, &needed, NULL, 0) == -1) {
+			if (errno == ENOMEM)
+				continue;
 			err(1, "sysctl(PF_ROUTE, NET_RT_FLAGS)");
+		}
 		lim = buf + needed;
-	} else
-		buf = lim = NULL;
+		break;
+	}
 
 	for (next = buf; next && next < lim; next += rtm->rtm_msglen) {
 		int isrouter = 0, prbs = 0;
diff --git a/usr.sbin/route6d/route6d.c b/usr.sbin/route6d/route6d.c
index 00ba8e12a0f..450e7140db4 100644
--- a/usr.sbin/route6d/route6d.c
+++ b/usr.sbin/route6d/route6d.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: route6d.c,v 1.55 2009/10/27 23:59:54 deraadt Exp $	*/
+/*	$OpenBSD: route6d.c,v 1.56 2013/03/21 04:43:17 deraadt Exp $	*/
 /*	$KAME: route6d.c,v 1.111 2006/10/25 06:38:13 jinmei Exp $	*/
 
 /*
@@ -2257,8 +2257,8 @@ int
 getifmtu(int ifindex)
 {
 	int	mib[6];
-	char	*buf;
-	size_t	msize;
+	char	*buf = NULL;
+	size_t	needed;
 	struct	if_msghdr *ifm;
 	int	mtu;
 
@@ -2268,17 +2268,19 @@ getifmtu(int ifindex)
 	mib[3] = AF_INET6;
 	mib[4] = NET_RT_IFLIST;
 	mib[5] = ifindex;
-	if (sysctl(mib, 6, NULL, &msize, NULL, 0) < 0) {
-		fatal("sysctl estimate NET_RT_IFLIST");
-		/*NOTREACHED*/
-	}
-	if ((buf = malloc(msize)) == NULL) {
-		fatal("malloc");
-		/*NOTREACHED*/
-	}
-	if (sysctl(mib, 6, buf, &msize, NULL, 0) < 0) {
-		fatal("sysctl NET_RT_IFLIST");
-		/*NOTREACHED*/
+	while (1) {
+		if (sysctl(mib, 6, NULL, &needed, NULL, 0) == -1)
+			fatal("sysctl estimate NET_RT_IFLIST");
+		if (needed == 0)
+			break;
+		if ((buf = realloc(buf, needed)) == NULL)
+			fatal("malloc");
+		if (sysctl(mib, 6, buf, &needed, NULL, 0) == -1) {
+			if (errno == ENOMEM)
+				continue;
+			fatal("sysctl NET_RT_IFLIST");
+		}
+		break;
 	}
 	ifm = (struct if_msghdr *)buf;
 	mtu = ifm->ifm_data.ifi_mtu;
diff --git a/usr.sbin/rtadvd/if.c b/usr.sbin/rtadvd/if.c
index 0917ff2851c..eb3f464adbc 100644
--- a/usr.sbin/rtadvd/if.c
+++ b/usr.sbin/rtadvd/if.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: if.c,v 1.24 2011/07/05 05:13:04 claudio Exp $	*/
+/*	$OpenBSD: if.c,v 1.25 2013/03/21 04:43:15 deraadt Exp $	*/
 /*	$KAME: if.c,v 1.17 2001/01/21 15:27:30 itojun Exp $	*/
 
 /*
@@ -437,14 +437,20 @@ get_iflist(char **buf, size_t *size)
 	mib[3] = AF_INET6;
 	mib[4] = NET_RT_IFLIST;
 	mib[5] = 0;
-
-	if (sysctl(mib, 6, NULL, size, NULL, 0) < 0)
-		fatal("sysctl: iflist size get failed");
-	if ((*buf = malloc(*size)) == NULL)
-		fatal("malloc");
-	if (sysctl(mib, 6, *buf, size, NULL, 0) < 0)
-		fatal("sysctl: iflist get failed");
-	return;
+	while (1) {
+		if (sysctl(mib, 6, NULL, size, NULL, 0) == -1)
+			fatal("sysctl: iflist size get failed");
+		if (*size == 0)
+			break;
+		if ((*buf = realloc(*buf, *size)) == NULL)
+			fatal("malloc");
+		if (sysctl(mib, 6, *buf, size, NULL, 0) == -1) {
+			if (errno == ENOMEM)
+				continue;
+			fatal("sysctl: iflist get failed");
+		}
+		break;
+	}
 }
 
 /*
diff --git a/usr.sbin/rwhod/rwhod.c b/usr.sbin/rwhod/rwhod.c
index 5a77492d007..61b6c8288a5 100644
--- a/usr.sbin/rwhod/rwhod.c
+++ b/usr.sbin/rwhod/rwhod.c
@@ -469,7 +469,7 @@ configure(void)
 	struct sockaddr_dl *sdl;
 	size_t needed;
 	int mib[6], flags = 0, len;
-	char *buf, *lim, *next;
+	char *buf = NULL, *lim, *next;
 	struct rt_addrinfo info;
 
 	mib[0] = CTL_NET;
@@ -478,13 +478,21 @@ configure(void)
 	mib[3] = AF_INET;
 	mib[4] = NET_RT_IFLIST;
 	mib[5] = 0;
-	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;
+	while (1) {
+		if (sysctl(mib, 6, NULL, &needed, NULL, 0) == -1)
+			quit("route-sysctl-estimate");
+		if (needed == 0)
+			break;
+		if ((buf = realloc(buf, needed)) == NULL)
+			quit("realloc");
+		if (sysctl(mib, 6, buf, &needed, NULL, 0) == -1) {
+			if (errno == ENOMEM)
+				continue;
+			quit("actual retrieval of interface table");
+		}
+		lim = buf + needed;
+		break;
+	}
 
 	sdl = NULL;		/* XXX just to keep gcc -Wall happy */
 	for (next = buf; next < lim; next += ifm->ifm_msglen) {