static void prog_attach_iptables(char *file)
{
int ret;
- char rules[100];
+ char rules[256];
if (bpf_obj_pin(prog_fd, file))
error(1, errno, "bpf_obj_pin");
printf("file path too long: %s\n", file);
exit(1);
}
- sprintf(rules, "iptables -A OUTPUT -m bpf --object-pinned %s -j ACCEPT",
- file);
+ ret = snprintf(rules, sizeof(rules),
+ "iptables -A OUTPUT -m bpf --object-pinned %s -j ACCEPT",
+ file);
+ if (ret < 0 || ret >= sizeof(rules)) {
+ printf("error constructing iptables command\n");
+ exit(1);
+ }
ret = system(rules);
if (ret < 0) {
printf("iptables rule update failed: %d/n", WEXITSTATUS(ret));