1 files changed, 127 insertions, 35 deletions

diff --git a/tools/testing/selftests/pidfd/pidfd_test.c b/tools/testing/selftests/pidfd/pidfd_test.c
index 7aff2d3b42c0..fcd85cad9f18 100644
--- a/tools/testing/selftests/pidfd/pidfd_test.c
+++ b/tools/testing/selftests/pidfd/pidfd_test.c
@@ -8,6 +8,7 @@
 #include <sched.h>
 #include <signal.h>
 #include <stdio.h>
+#include <stdbool.h>
 #include <stdlib.h>
 #include <string.h>
 #include <syscall.h>
@@ -27,6 +28,8 @@
 
 #define MAX_EVENTS 5
 
+static bool have_pidfd_send_signal;
+
 static pid_t pidfd_clone(int flags, int *pidfd, int (*fn)(void *))
 {
 	size_t stack_size = 1024;
@@ -39,12 +42,41 @@ static pid_t pidfd_clone(int flags, int *pidfd, int (*fn)(void *))
 #endif
 }
 
-static int signal_received;
+static pthread_t signal_received;
 
 static void set_signal_received_on_sigusr1(int sig)
 {
 	if (sig == SIGUSR1)
-		signal_received = 1;
+		signal_received = pthread_self();
+}
+
+static int send_signal(int pidfd)
+{
+	int ret = 0;
+
+	if (sys_pidfd_send_signal(pidfd, SIGUSR1, NULL, 0) < 0) {
+		ret = -EINVAL;
+		goto exit;
+	}
+
+	if (signal_received != pthread_self()) {
+		ret = -EINVAL;
+		goto exit;
+	}
+
+exit:
+	signal_received = 0;
+	return ret;
+}
+
+static void *send_signal_worker(void *arg)
+{
+	int pidfd = (int)(intptr_t)arg;
+	int ret;
+
+	/* We forward any errors for the caller to handle. */
+	ret = send_signal(pidfd);
+	return (void *)(intptr_t)ret;
 }
 
 /*
@@ -53,28 +85,58 @@ static void set_signal_received_on_sigusr1(int sig)
  */
 static int test_pidfd_send_signal_simple_success(void)
 {
-	int pidfd, ret;
+	int pidfd;
 	const char *test_name = "pidfd_send_signal send SIGUSR1";
+	pthread_t thread;
+	void *thread_res;
+	int err;
+
+	if (!have_pidfd_send_signal) {
+		ksft_test_result_skip(
+			"%s test: pidfd_send_signal() syscall not supported\n",
+			test_name);
+		return 0;
+	}
 
+	signal(SIGUSR1, set_signal_received_on_sigusr1);
+
+	/* Try sending a signal to ourselves via /proc/self. */
 	pidfd = open("/proc/self", O_DIRECTORY | O_CLOEXEC);
 	if (pidfd < 0)
 		ksft_exit_fail_msg(
 			"%s test: Failed to open process file descriptor\n",
 			test_name);
+	err = send_signal(pidfd);
+	if (err)
+		ksft_exit_fail_msg(
+			"%s test: Error %d on sending pidfd signal\n",
+			test_name, err);
+	close(pidfd);
 
-	signal(SIGUSR1, set_signal_received_on_sigusr1);
+	/* Now try the same thing only using PIDFD_SELF_THREAD_GROUP. */
+	err = send_signal(PIDFD_SELF_THREAD_GROUP);
+	if (err)
+		ksft_exit_fail_msg(
+			"%s test: Error %d on PIDFD_SELF_THREAD_GROUP signal\n",
+			test_name, err);
 
-	ret = sys_pidfd_send_signal(pidfd, SIGUSR1, NULL, 0);
-	close(pidfd);
-	if (ret < 0)
-		ksft_exit_fail_msg("%s test: Failed to send signal\n",
+	/*
+	 * Now try the same thing in a thread and assert thread ID is equal to
+	 * worker thread ID.
+	 */
+	if (pthread_create(&thread, NULL, send_signal_worker,
+			   (void *)(intptr_t)PIDFD_SELF_THREAD))
+		ksft_exit_fail_msg("%s test: Failed to create thread\n",
 				   test_name);
-
-	if (signal_received != 1)
-		ksft_exit_fail_msg("%s test: Failed to receive signal\n",
+	if (pthread_join(thread, &thread_res))
+		ksft_exit_fail_msg("%s test: Failed to join thread\n",
 				   test_name);
+	err = (int)(intptr_t)thread_res;
+	if (err)
+		ksft_exit_fail_msg(
+			"%s test: Error %d on PIDFD_SELF_THREAD signal\n",
+			test_name, err);
 
-	signal_received = 0;
 	ksft_test_result_pass("%s test: Sent signal\n", test_name);
 	return 0;
 }
@@ -86,6 +148,13 @@ static int test_pidfd_send_signal_exited_fail(void)
 	pid_t pid;
 	const char *test_name = "pidfd_send_signal signal exited process";
 
+	if (!have_pidfd_send_signal) {
+		ksft_test_result_skip(
+			"%s test: pidfd_send_signal() syscall not supported\n",
+			test_name);
+		return 0;
+	}
+
 	pid = fork();
 	if (pid < 0)
 		ksft_exit_fail_msg("%s test: Failed to create new process\n",
@@ -98,7 +167,8 @@ static int test_pidfd_send_signal_exited_fail(void)
 
 	pidfd = open(buf, O_DIRECTORY | O_CLOEXEC);
 
-	(void)wait_for_pid(pid);
+	ret = wait_for_pid(pid);
+	ksft_print_msg("waitpid WEXITSTATUS=%d\n", ret);
 
 	if (pidfd < 0)
 		ksft_exit_fail_msg(
@@ -137,16 +207,34 @@ static int test_pidfd_send_signal_recycled_pid_fail(void)
 	pid_t pid1;
 	const char *test_name = "pidfd_send_signal signal recycled pid";
 
+	if (!have_pidfd_send_signal) {
+		ksft_test_result_skip(
+			"%s test: pidfd_send_signal() syscall not supported\n",
+			test_name);
+		return 0;
+	}
+
 	ret = unshare(CLONE_NEWPID);
-	if (ret < 0)
+	if (ret < 0) {
+		if (errno == EPERM) {
+			ksft_test_result_skip("%s test: Unsharing pid namespace not permitted\n",
+					      test_name);
+			return 0;
+		}
 		ksft_exit_fail_msg("%s test: Failed to unshare pid namespace\n",
 				   test_name);
+	}
 
 	ret = unshare(CLONE_NEWNS);
-	if (ret < 0)
-		ksft_exit_fail_msg(
-			"%s test: Failed to unshare mount namespace\n",
-			test_name);
+	if (ret < 0) {
+		if (errno == EPERM) {
+			ksft_test_result_skip("%s test: Unsharing mount namespace not permitted\n",
+					      test_name);
+			return 0;
+		}
+		ksft_exit_fail_msg("%s test: Failed to unshare mount namespace\n",
+				   test_name);
+	}
 
 	ret = mount(NULL, "/", NULL, MS_REC | MS_PRIVATE, 0);
 	if (ret < 0)
@@ -295,7 +383,7 @@ static int test_pidfd_send_signal_recycled_pid_fail(void)
 		ksft_exit_fail_msg("%s test: Failed to recycle pid %d\n",
 				   test_name, PID_RECYCLE);
 	case PIDFD_SKIP:
-		ksft_print_msg("%s test: Skipping test\n", test_name);
+		ksft_test_result_skip("%s test: Skipping test\n", test_name);
 		ret = 0;
 		break;
 	case PIDFD_XFAIL:
@@ -325,15 +413,17 @@ static int test_pidfd_send_signal_syscall_support(void)
 
 	ret = sys_pidfd_send_signal(pidfd, 0, NULL, 0);
 	if (ret < 0) {
-		if (errno == ENOSYS)
-			ksft_exit_skip(
+		if (errno == ENOSYS) {
+			ksft_test_result_skip(
 				"%s test: pidfd_send_signal() syscall not supported\n",
 				test_name);
-
+			return 0;
+		}
 		ksft_exit_fail_msg("%s test: Failed to send signal\n",
 				   test_name);
 	}
 
+	have_pidfd_send_signal = true;
 	close(pidfd);
 	ksft_test_result_pass(
 		"%s test: pidfd_send_signal() syscall is supported. Tests can be executed\n",
@@ -343,13 +433,13 @@ static int test_pidfd_send_signal_syscall_support(void)
 
 static void *test_pidfd_poll_exec_thread(void *priv)
 {
-	ksft_print_msg("Child Thread: starting. pid %d tid %d ; and sleeping\n",
+	ksft_print_msg("Child Thread: starting. pid %d tid %ld ; and sleeping\n",
 			getpid(), syscall(SYS_gettid));
 	ksft_print_msg("Child Thread: doing exec of sleep\n");
 
 	execl("/bin/sleep", "sleep", str(CHILD_THREAD_MIN_WAIT), (char *)NULL);
 
-	ksft_print_msg("Child Thread: DONE. pid %d tid %d\n",
+	ksft_print_msg("Child Thread: DONE. pid %d tid %ld\n",
 			getpid(), syscall(SYS_gettid));
 	return NULL;
 }
@@ -376,7 +466,7 @@ static void poll_pidfd(const char *test_name, int pidfd)
 
 	c = epoll_wait(epoll_fd, events, MAX_EVENTS, 5000);
 	if (c != 1 || !(events[0].events & EPOLLIN))
-		ksft_exit_fail_msg("%s test: Unexpected epoll_wait result (c=%d, events=%x) ",
+		ksft_exit_fail_msg("%s test: Unexpected epoll_wait result (c=%d, events=%x) "
 				   "(errno %d)\n",
 				   test_name, c, events[0].events, errno);
 
@@ -389,7 +479,7 @@ static int child_poll_exec_test(void *args)
 {
 	pthread_t t1;
 
-	ksft_print_msg("Child (pidfd): starting. pid %d tid %d\n", getpid(),
+	ksft_print_msg("Child (pidfd): starting. pid %d tid %ld\n", getpid(),
 			syscall(SYS_gettid));
 	pthread_create(&t1, NULL, test_pidfd_poll_exec_thread, NULL);
 	/*
@@ -398,13 +488,14 @@ static int child_poll_exec_test(void *args)
 	 */
 	while (1)
 		sleep(1);
+
+	return 0;
 }
 
 static void test_pidfd_poll_exec(int use_waitpid)
 {
 	int pid, pidfd = 0;
 	int status, ret;
-	pthread_t t1;
 	time_t prog_start = time(NULL);
 	const char *test_name = "pidfd_poll check for premature notification on child thread exec";
 
@@ -441,10 +532,10 @@ static void test_pidfd_poll_exec(int use_waitpid)
 
 static void *test_pidfd_poll_leader_exit_thread(void *priv)
 {
-	ksft_print_msg("Child Thread: starting. pid %d tid %d ; and sleeping\n",
+	ksft_print_msg("Child Thread: starting. pid %d tid %ld ; and sleeping\n",
 			getpid(), syscall(SYS_gettid));
 	sleep(CHILD_THREAD_MIN_WAIT);
-	ksft_print_msg("Child Thread: DONE. pid %d tid %d\n", getpid(), syscall(SYS_gettid));
+	ksft_print_msg("Child Thread: DONE. pid %d tid %ld\n", getpid(), syscall(SYS_gettid));
 	return NULL;
 }
 
@@ -453,23 +544,24 @@ static int child_poll_leader_exit_test(void *args)
 {
 	pthread_t t1, t2;
 
-	ksft_print_msg("Child: starting. pid %d tid %d\n", getpid(), syscall(SYS_gettid));
+	ksft_print_msg("Child: starting. pid %d tid %ld\n", getpid(), syscall(SYS_gettid));
 	pthread_create(&t1, NULL, test_pidfd_poll_leader_exit_thread, NULL);
 	pthread_create(&t2, NULL, test_pidfd_poll_leader_exit_thread, NULL);
 
 	/*
-	 * glibc exit calls exit_group syscall, so explicity call exit only
+	 * glibc exit calls exit_group syscall, so explicitly call exit only
 	 * so that only the group leader exits, leaving the threads alone.
 	 */
 	*child_exit_secs = time(NULL);
 	syscall(SYS_exit, 0);
+	/* Never reached, but appeases compiler thinking we should return. */
+	exit(0);
 }
 
 static void test_pidfd_poll_leader_exit(int use_waitpid)
 {
 	int pid, pidfd = 0;
-	int status, ret;
-	time_t prog_start = time(NULL);
+	int status, ret = 0;
 	const char *test_name = "pidfd_poll check for premature notification on non-empty"
 				"group leader exit";
 
@@ -521,7 +613,7 @@ static void test_pidfd_poll_leader_exit(int use_waitpid)
 int main(int argc, char **argv)
 {
 	ksft_print_header();
-	ksft_set_plan(4);
+	ksft_set_plan(8);
 
 	test_pidfd_poll_exec(0);
 	test_pidfd_poll_exec(1);
@@ -532,5 +624,5 @@ int main(int argc, char **argv)
 	test_pidfd_send_signal_exited_fail();
 	test_pidfd_send_signal_recycled_pid_fail();
 
-	return ksft_exit_pass();
+	ksft_exit_pass();
 }