From ee10198a39b9363f3ff122769e8391f4b50d2074 Mon Sep 17 00:00:00 2001
From: Sven Schmitt <sven.schmitt@gmx.net>
Date: Thu, 25 Jun 2015 10:34:04 +0200
Subject: [PATCH] replaced ifr by simple char if_name[IFNAMSIZ] in isotpsniffer
 and null terminated ifr.ifr_name (strncpy doesn't do that for us).

---
 cansend.c      |  3 ++-
 isotpsniffer.c | 16 ++++++----------
 isotptun.c     |  3 ++-
 3 files changed, 10 insertions(+), 12 deletions(-)

diff --git a/cansend.c b/cansend.c
index a0b9bbb..c2629e1 100644
--- a/cansend.c
+++ b/cansend.c
@@ -94,7 +94,8 @@ int main(int argc, char **argv)
 		return 1;
 	}
 
-	strncpy(ifr.ifr_name, argv[1], IFNAMSIZ);
+	strncpy(ifr.ifr_name, argv[1], IFNAMSIZ-1);
+	ifr.ifr_name[IFNAMSIZ-1] = '\0';
 	ifr.ifr_ifindex = if_nametoindex(ifr.ifr_name);
 	if (!ifr.ifr_ifindex) {
 		perror("if_nametoindex");
diff --git a/isotpsniffer.c b/isotpsniffer.c
index 9182fcc..36c5c03 100644
--- a/isotpsniffer.c
+++ b/isotpsniffer.c
@@ -175,7 +175,7 @@ int main(int argc, char **argv)
 	fd_set rdfs;
 	int s, t;
 	struct sockaddr_can addr;
-	struct ifreq ifr;
+	char if_name[IFNAMSIZ];
 	static struct can_isotp_options opts;
 	int opt, quit = 0;
 	int color = 0;
@@ -271,15 +271,11 @@ int main(int argc, char **argv)
 
 	opts.flags |= CAN_ISOTP_LISTEN_MODE;
 
-	strncpy(ifr.ifr_name, argv[optind], IFNAMSIZ);
-	ifr.ifr_ifindex = if_nametoindex(ifr.ifr_name);
-	if (!ifr.ifr_ifindex) {
-		perror("if_nametoindex");
-		return 1;
-	}
+	strncpy(if_name, argv[optind], IFNAMSIZ-1);
+	if_name[IFNAMSIZ-1] = '\0';
 
 	addr.can_family = AF_CAN;
-	addr.can_ifindex = ifr.ifr_ifindex;
+	addr.can_ifindex = if_nametoindex(if_name);
 
 	setsockopt(s, SOL_CAN_ISOTP, CAN_ISOTP_OPTS, &opts, sizeof(opts));
 
@@ -339,7 +335,7 @@ int main(int argc, char **argv)
 			if (nbytes > 4095)
 				return -1;
 			printbuf(buffer, nbytes, color?2:0, timestamp, format,
-				 &tv, &last_tv, dst, s, ifr.ifr_name, head);
+				 &tv, &last_tv, dst, s, if_name, head);
 		}
 
 		if (FD_ISSET(t, &rdfs)) {
@@ -351,7 +347,7 @@ int main(int argc, char **argv)
 			if (nbytes > 4095)
 				return -1;
 			printbuf(buffer, nbytes, color?1:0, timestamp, format,
-				 &tv, &last_tv, src, t, ifr.ifr_name, head);
+				 &tv, &last_tv, src, t, if_name, head);
 		}
 	}
 
diff --git a/isotptun.c b/isotptun.c
index 400e1b7..0c88188 100644
--- a/isotptun.c
+++ b/isotptun.c
@@ -291,7 +291,8 @@ int main(int argc, char **argv)
 
 	memset(&ifr, 0, sizeof(ifr));
 	ifr.ifr_flags = IFF_TUN | IFF_NO_PI;
-	strncpy(ifr.ifr_name, name, IFNAMSIZ);
+	strncpy(ifr.ifr_name, name, IFNAMSIZ-1);
+	ifr.ifr_name[IFNAMSIZ-1] = '\0';
 
 	if (ioctl(t, TUNSETIFF, (void *) &ifr) < 0) {
 		perror("ioctl tunfd");