trafgen: fix NULL pointer dereference in -i option parsing

If trafgen is called with the -i option, it currently crashes due to an
NULL pointer dereference. Fix it.

Fixes Coverity CID 1381809
Fixes: 82a3c204c6f1 ("trafgen: Allow send packets from pcap file")
Signed-off-by: Tobias Klauser <tklauser@distanz.ch>

1 files changed, 3 insertions, 5 deletions

diff --git a/trafgen.c b/trafgen.c
index 9c5a9a6..d2d43bb 100644
--- a/trafgen.c
+++ b/trafgen.c
@@ -1097,15 +1097,13 @@ int main(int argc, char **argv)
 		case 'J':
 			ctx.jumbo_support = true;
 			break;
+		case 'c':
 		case 'i':
 			confname = xstrdup(optarg);
-			if (strstr(confname, ".pcap")) {
+			if (c == 'i' && strstr(confname, ".pcap")) {
 				ctx.sh.type = SHAPER_TSTAMP;
 				ctx.pcap_in = confname;
-				break;
-			}
-		case 'c':
-			if (!strncmp("-", confname, strlen("-")))
+			} else if (!strncmp("-", confname, strlen("-")))
 				ctx.cpus = 1;
 			break;
 		case 'u':