Re: [PATCH RESEND 3/5] selftests/seccomp: Add test for wait killable notifier

[Tycho Andersen]

On Mon, Apr 26, 2021 at 11:06:08AM -0700, Sargun Dhillon wrote:
> +TEST(user_notification_signal_wait_killable)
> +{
> +	pid_t pid;
> +	long ret;
> +	int status, listener, sk_pair[2];
> +	struct seccomp_notif req = {
> +		.flags = SECCOMP_USER_NOTIF_FLAG_WAIT_KILLABLE,
> +	};
> +	struct seccomp_notif_resp resp = {};
> +	char c;
> +
> +	ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
> +	ASSERT_EQ(0, ret) {
> +		TH_LOG("Kernel does not support PR_SET_NO_NEW_PRIVS!");
> +	}
> +
> +	ASSERT_EQ(socketpair(PF_LOCAL, SOCK_SEQPACKET, 0, sk_pair), 0);
> +	ASSERT_EQ(fcntl(sk_pair[0], F_SETFL, O_NONBLOCK), 0);
> +
> +	listener = user_notif_syscall(__NR_gettid,
> +				      SECCOMP_FILTER_FLAG_NEW_LISTENER);
> +	ASSERT_GE(listener, 0);
> +
> +	pid = fork();
> +	ASSERT_GE(pid, 0);
> +
> +	if (pid == 0) {
> +		close(sk_pair[0]);
> +		handled = sk_pair[1];
> +		if (signal(SIGUSR1, signal_handler) == SIG_ERR) {

I think here you want a write(handled, "x", 1), right?

Tycho