pppoe-discovery: Add check that there is no additional extra argument

Signed-off-by: Pali Rohár <pali@kernel.org>

1 files changed, 6 insertions, 0 deletions

diff --git a/pppd/plugins/pppoe/pppoe-discovery.c b/pppd/plugins/pppoe/pppoe-discovery.c
index 4ac5106..e93d781 100644
--- a/pppd/plugins/pppoe/pppoe-discovery.c
+++ b/pppd/plugins/pppoe/pppoe-discovery.c
@@ -251,6 +251,12 @@ int main(int argc, char *argv[])
 	}
     }
 
+    if (optind != argc) {
+	fprintf(stderr, "%s: extra argument '%s'\n", argv[0], argv[optind]);
+	usage();
+	exit(EXIT_FAILURE);
+    }
+
     if (!conn->ifName) {
 	fprintf(stderr, "Interface was not specified\n");
 	exit(EXIT_FAILURE);