Use strlcpy() instead of strncpy() when copying ifname to ensure

that it is NUL terminated.  Additional NUL padding is not required
for short names.

Use sizeof(destination) in a few places instead of IFNAMSIZ.

Cast afp->af_ridreq and afp->af_addreq  to make the intent of
the code more obvious.

Reported by:	Coverity
CID:		1009628, 1009630, 1009631, 1009632, 1009633, 1009635, 1009638
CID:		1009639, 1009640, 1009641, 1009642, 1009643, 1009644, 1009645
CID:		1009646, 1009647, 1010049, 1010050, 1010051, 1010052, 1010053
CID:		1010054, 1011293, 1011294, 1011295, 1011296, 1011297, 1011298
CID:		1011299, 1305821, 1351720, 1351721
MFC after:	1 week

1 files changed, 12 insertions, 10 deletions

diff --git a/sbin/ifconfig/ifconfig.c b/sbin/ifconfig/ifconfig.c
index a475139..001850f 100644
--- a/sbin/ifconfig/ifconfig.c
+++ b/sbin/ifconfig/ifconfig.c
@@ -472,7 +472,7 @@ main(int argc, char *argv[])
 	ifindex = 0;
 	for (ifa = sifap; ifa; ifa = ifa->ifa_next) {
 		memset(&paifr, 0, sizeof(paifr));
-		strncpy(paifr.ifr_name, ifa->ifa_name, sizeof(paifr.ifr_name));
+		strlcpy(paifr.ifr_name, ifa->ifa_name, sizeof(paifr.ifr_name));
 		if (sizeof(paifr.ifr_addr) >= ifa->ifa_addr->sa_len) {
 			memcpy(&paifr.ifr_addr, ifa->ifa_addr,
 			    ifa->ifa_addr->sa_len);
@@ -671,7 +671,7 @@ ifconfig(int argc, char *const *argv, int iscreate, const struct afswtch *uafp)
 	struct callback *cb;
 	int s;
 
-	strncpy(ifr.ifr_name, name, sizeof ifr.ifr_name);
+	strlcpy(ifr.ifr_name, name, sizeof ifr.ifr_name);
 	afp = NULL;
 	if (uafp != NULL)
 		afp = uafp;
@@ -792,7 +792,8 @@ top:
 	}
 	if (clearaddr) {
 		int ret;
-		strncpy(afp->af_ridreq, name, sizeof ifr.ifr_name);
+		strlcpy(((struct ifreq *)afp->af_ridreq)->ifr_name, name,
+			sizeof ifr.ifr_name);
 		ret = ioctl(s, afp->af_difaddr, afp->af_ridreq);
 		if (ret < 0) {
 			if (errno == EADDRNOTAVAIL && (doalias >= 0)) {
@@ -809,7 +810,8 @@ top:
 		}
 	}
 	if (newaddr && (setaddr || setmask)) {
-		strncpy(afp->af_addreq, name, sizeof ifr.ifr_name);
+		strlcpy(((struct ifreq *)afp->af_addreq)->ifr_name, name,
+			sizeof ifr.ifr_name);
 		if (ioctl(s, afp->af_aifaddr, afp->af_addreq) < 0)
 			Perror("ioctl (SIOCAIFADDR)");
 	}
@@ -1005,7 +1007,7 @@ static void
 setifmetric(const char *val, int dummy __unused, int s, 
     const struct afswtch *afp)
 {
-	strncpy(ifr.ifr_name, name, sizeof (ifr.ifr_name));
+	strlcpy(ifr.ifr_name, name, sizeof (ifr.ifr_name));
 	ifr.ifr_metric = atoi(val);
 	if (ioctl(s, SIOCSIFMETRIC, (caddr_t)&ifr) < 0)
 		err(1, "ioctl SIOCSIFMETRIC (set metric)");
@@ -1015,7 +1017,7 @@ static void
 setifmtu(const char *val, int dummy __unused, int s, 
     const struct afswtch *afp)
 {
-	strncpy(ifr.ifr_name, name, sizeof (ifr.ifr_name));
+	strlcpy(ifr.ifr_name, name, sizeof (ifr.ifr_name));
 	ifr.ifr_mtu = atoi(val);
 	if (ioctl(s, SIOCSIFMTU, (caddr_t)&ifr) < 0)
 		err(1, "ioctl SIOCSIFMTU (set mtu)");
@@ -1027,7 +1029,7 @@ setifname(const char *val, int dummy __unused, int s,
 {
 	char *newname;
 	
-	strncpy(ifr.ifr_name, name, sizeof(ifr.ifr_name));
+	strlcpy(ifr.ifr_name, name, sizeof(ifr.ifr_name));
 
 	newname = strdup(val);
 	if (newname == NULL)
@@ -1049,7 +1051,7 @@ setifdescr(const char *val, int dummy __unused, int s,
 {
 	char *newdescr;
 
-	strncpy(ifr.ifr_name, name, sizeof(ifr.ifr_name));
+	strlcpy(ifr.ifr_name, name, sizeof(ifr.ifr_name));
 	
 	ifr.ifr_buffer.length = strlen(val) + 1;
 	if (ifr.ifr_buffer.length == 1) {
@@ -1109,7 +1111,7 @@ status(const struct afswtch *afp, const struct sockaddr_dl *sdl,
 		ifr.ifr_addr.sa_family =
 		    afp->af_af == AF_LINK ? AF_LOCAL : afp->af_af;
 	}
-	strncpy(ifr.ifr_name, name, sizeof(ifr.ifr_name));
+	strlcpy(ifr.ifr_name, name, sizeof(ifr.ifr_name));
 
 	s = socket(ifr.ifr_addr.sa_family, SOCK_DGRAM, 0);
 	if (s < 0)
@@ -1191,7 +1193,7 @@ status(const struct afswtch *afp, const struct sockaddr_dl *sdl,
 	else if (afp->af_other_status != NULL)
 		afp->af_other_status(s);
 
-	strncpy(ifs.ifs_name, name, sizeof ifs.ifs_name);
+	strlcpy(ifs.ifs_name, name, sizeof ifs.ifs_name);
 	if (ioctl(s, SIOCGIFSTATUS, &ifs) == 0) 
 		printf("%s", ifs.ascii);