close soc if ioctl fails

src/main.c

@@ -395,6 +395,7 @@ int main(int argc, char **argv) {
                 strcpy(ifr.ifr_name, "can0");
                 if (ioctl(soc, SIOCGIFINDEX, &ifr) < 0) {
                         perror("ioctl error");
+                        close(soc);
                         return 1;
                 }
                 addr.can_family = AF_CAN;