aboutsummaryrefslogtreecommitdiff
diff options
context:
space:
mode:
authorStephen Rothwell <sfr@canb.auug.org.au>2019-01-18 13:51:48 +1100
committerStephen Rothwell <sfr@canb.auug.org.au>2019-01-18 13:51:48 +1100
commit17521429e78bfc6ef558de8e749e65d4bf1aa0bd (patch)
tree6800b6d11d2a72632031dc70d761b9761eeccbfa
parenteda3a65be24912ea9edd6a6b98ae29df020f9cad (diff)
parent4607de57fff546f7ba957ab067dfbc019755d641 (diff)
download96b-common-17521429e78bfc6ef558de8e749e65d4bf1aa0bd.tar.gz
Merge remote-tracking branch 'pidfd/for-next'
-rw-r--r--arch/x86/entry/syscalls/syscall_32.tbl1
-rw-r--r--arch/x86/entry/syscalls/syscall_64.tbl1
-rw-r--r--fs/proc/base.c9
-rw-r--r--include/linux/proc_fs.h6
-rw-r--r--include/linux/syscalls.h3
-rw-r--r--include/uapi/asm-generic/unistd.h4
-rw-r--r--kernel/signal.c133
-rw-r--r--kernel/sys_ni.c1
-rw-r--r--tools/testing/selftests/Makefile1
-rw-r--r--tools/testing/selftests/pidfd/Makefile6
-rw-r--r--tools/testing/selftests/pidfd/pidfd_test.c381
11 files changed, 539 insertions, 7 deletions
diff --git a/arch/x86/entry/syscalls/syscall_32.tbl b/arch/x86/entry/syscalls/syscall_32.tbl
index 3cf7b533b3d1..6804c1e84b36 100644
--- a/arch/x86/entry/syscalls/syscall_32.tbl
+++ b/arch/x86/entry/syscalls/syscall_32.tbl
@@ -398,3 +398,4 @@
384 i386 arch_prctl sys_arch_prctl __ia32_compat_sys_arch_prctl
385 i386 io_pgetevents sys_io_pgetevents __ia32_compat_sys_io_pgetevents
386 i386 rseq sys_rseq __ia32_sys_rseq
+387 i386 pidfd_send_signal sys_pidfd_send_signal __ia32_sys_pidfd_send_signal
diff --git a/arch/x86/entry/syscalls/syscall_64.tbl b/arch/x86/entry/syscalls/syscall_64.tbl
index f0b1709a5ffb..aa4b858fa0f1 100644
--- a/arch/x86/entry/syscalls/syscall_64.tbl
+++ b/arch/x86/entry/syscalls/syscall_64.tbl
@@ -343,6 +343,7 @@
332 common statx __x64_sys_statx
333 common io_pgetevents __x64_sys_io_pgetevents
334 common rseq __x64_sys_rseq
+335 common pidfd_send_signal __x64_sys_pidfd_send_signal
#
# x32-specific system call numbers start at 512 to avoid cache impact
diff --git a/fs/proc/base.c b/fs/proc/base.c
index c9d775fd24ef..02ca5f1d9523 100644
--- a/fs/proc/base.c
+++ b/fs/proc/base.c
@@ -3092,6 +3092,15 @@ static const struct file_operations proc_tgid_base_operations = {
.llseek = generic_file_llseek,
};
+struct pid *tgid_pidfd_to_pid(const struct file *file)
+{
+ if (!d_is_dir(file->f_path.dentry) ||
+ (file->f_op != &proc_tgid_base_operations))
+ return ERR_PTR(-EBADF);
+
+ return proc_pid(file_inode(file));
+}
+
static struct dentry *proc_tgid_base_lookup(struct inode *dir, struct dentry *dentry, unsigned int flags)
{
return proc_pident_lookup(dir, dentry,
diff --git a/include/linux/proc_fs.h b/include/linux/proc_fs.h
index d0e1f1522a78..52a283ba0465 100644
--- a/include/linux/proc_fs.h
+++ b/include/linux/proc_fs.h
@@ -73,6 +73,7 @@ struct proc_dir_entry *proc_create_net_single_write(const char *name, umode_t mo
int (*show)(struct seq_file *, void *),
proc_write_t write,
void *data);
+extern struct pid *tgid_pidfd_to_pid(const struct file *file);
#else /* CONFIG_PROC_FS */
@@ -114,6 +115,11 @@ static inline int remove_proc_subtree(const char *name, struct proc_dir_entry *p
#define proc_create_net(name, mode, parent, state_size, ops) ({NULL;})
#define proc_create_net_single(name, mode, parent, show, data) ({NULL;})
+static inline struct pid *tgid_pidfd_to_pid(const struct file *file)
+{
+ return ERR_PTR(-EBADF);
+}
+
#endif /* CONFIG_PROC_FS */
struct net;
diff --git a/include/linux/syscalls.h b/include/linux/syscalls.h
index 257cccba3062..5eb2e351675e 100644
--- a/include/linux/syscalls.h
+++ b/include/linux/syscalls.h
@@ -926,6 +926,9 @@ asmlinkage long sys_statx(int dfd, const char __user *path, unsigned flags,
unsigned mask, struct statx __user *buffer);
asmlinkage long sys_rseq(struct rseq __user *rseq, uint32_t rseq_len,
int flags, uint32_t sig);
+asmlinkage long sys_pidfd_send_signal(int pidfd, int sig,
+ siginfo_t __user *info,
+ unsigned int flags);
/*
* Architecture-specific system calls
diff --git a/include/uapi/asm-generic/unistd.h b/include/uapi/asm-generic/unistd.h
index d90127298f12..b77538af7aca 100644
--- a/include/uapi/asm-generic/unistd.h
+++ b/include/uapi/asm-generic/unistd.h
@@ -740,9 +740,11 @@ __SC_COMP(__NR_io_pgetevents, sys_io_pgetevents, compat_sys_io_pgetevents)
__SYSCALL(__NR_rseq, sys_rseq)
#define __NR_kexec_file_load 294
__SYSCALL(__NR_kexec_file_load, sys_kexec_file_load)
+#define __NR_pidfd_send_signal 295
+__SYSCALL(__NR_pidfd_send_signal, sys_pidfd_send_signal)
#undef __NR_syscalls
-#define __NR_syscalls 295
+#define __NR_syscalls 296
/*
* 32 bit systems traditionally used different
diff --git a/kernel/signal.c b/kernel/signal.c
index e1d7ad8e6ab1..268bed80244f 100644
--- a/kernel/signal.c
+++ b/kernel/signal.c
@@ -19,7 +19,9 @@
#include <linux/sched/task.h>
#include <linux/sched/task_stack.h>
#include <linux/sched/cputime.h>
+#include <linux/file.h>
#include <linux/fs.h>
+#include <linux/proc_fs.h>
#include <linux/tty.h>
#include <linux/binfmts.h>
#include <linux/coredump.h>
@@ -3429,6 +3431,16 @@ COMPAT_SYSCALL_DEFINE4(rt_sigtimedwait, compat_sigset_t __user *, uthese,
#endif
#endif
+static inline void prepare_kill_siginfo(int sig, struct kernel_siginfo *info)
+{
+ clear_siginfo(info);
+ info->si_signo = sig;
+ info->si_errno = 0;
+ info->si_code = SI_USER;
+ info->si_pid = task_tgid_vnr(current);
+ info->si_uid = from_kuid_munged(current_user_ns(), current_uid());
+}
+
/**
* sys_kill - send a signal to a process
* @pid: the PID of the process
@@ -3438,16 +3450,125 @@ SYSCALL_DEFINE2(kill, pid_t, pid, int, sig)
{
struct kernel_siginfo info;
- clear_siginfo(&info);
- info.si_signo = sig;
- info.si_errno = 0;
- info.si_code = SI_USER;
- info.si_pid = task_tgid_vnr(current);
- info.si_uid = from_kuid_munged(current_user_ns(), current_uid());
+ prepare_kill_siginfo(sig, &info);
return kill_something_info(sig, &info, pid);
}
+#ifdef CONFIG_PROC_FS
+/*
+ * Verify that the signaler and signalee either are in the same pid namespace
+ * or that the signaler's pid namespace is an ancestor of the signalee's pid
+ * namespace.
+ */
+static bool access_pidfd_pidns(struct pid *pid)
+{
+ struct pid_namespace *active = task_active_pid_ns(current);
+ struct pid_namespace *p = ns_of_pid(pid);
+
+ for (;;) {
+ if (!p)
+ return false;
+ if (p == active)
+ break;
+ p = p->parent;
+ }
+
+ return true;
+}
+
+static int copy_siginfo_from_user_any(kernel_siginfo_t *kinfo, siginfo_t *info)
+{
+#ifdef CONFIG_COMPAT
+ /*
+ * Avoid hooking up compat syscalls and instead handle necessary
+ * conversions here. Note, this is a stop-gap measure and should not be
+ * considered a generic solution.
+ */
+ if (in_compat_syscall())
+ return copy_siginfo_from_user32(
+ kinfo, (struct compat_siginfo __user *)info);
+#endif
+ return copy_siginfo_from_user(kinfo, info);
+}
+
+/**
+ * sys_pidfd_send_signal - send a signal to a process through a task file
+ * descriptor
+ * @pidfd: the file descriptor of the process
+ * @sig: signal to be sent
+ * @info: the signal info
+ * @flags: future flags to be passed
+ *
+ * The syscall currently only signals via PIDTYPE_PID which covers
+ * kill(<positive-pid>, <signal>. It does not signal threads or process
+ * groups.
+ * In order to extend the syscall to threads and process groups the @flags
+ * argument should be used. In essence, the @flags argument will determine
+ * what is signaled and not the file descriptor itself. Put in other words,
+ * grouping is a property of the flags argument not a property of the file
+ * descriptor.
+ *
+ * Return: 0 on success, negative errno on failure
+ */
+SYSCALL_DEFINE4(pidfd_send_signal, int, pidfd, int, sig,
+ siginfo_t __user *, info, unsigned int, flags)
+{
+ int ret;
+ struct fd f;
+ struct pid *pid;
+ kernel_siginfo_t kinfo;
+
+ /* Enforce flags be set to 0 until we add an extension. */
+ if (flags)
+ return -EINVAL;
+
+ f = fdget_raw(pidfd);
+ if (!f.file)
+ return -EBADF;
+
+ /* Is this a pidfd? */
+ pid = tgid_pidfd_to_pid(f.file);
+ if (IS_ERR(pid)) {
+ ret = PTR_ERR(pid);
+ goto err;
+ }
+
+ ret = -EINVAL;
+ if (!access_pidfd_pidns(pid))
+ goto err;
+
+ if (info) {
+ ret = copy_siginfo_from_user_any(&kinfo, info);
+ if (unlikely(ret))
+ goto err;
+
+ ret = -EINVAL;
+ if (unlikely(sig != kinfo.si_signo))
+ goto err;
+
+ if ((task_pid(current) != pid) &&
+ (kinfo.si_code >= 0 || kinfo.si_code == SI_TKILL)) {
+ /* Only allow sending arbitrary signals to yourself. */
+ ret = -EPERM;
+ if (kinfo.si_code != SI_USER)
+ goto err;
+
+ /* Turn this into a regular kill signal. */
+ prepare_kill_siginfo(sig, &kinfo);
+ }
+ } else {
+ prepare_kill_siginfo(sig, &kinfo);
+ }
+
+ ret = kill_pid_info(sig, &kinfo, pid);
+
+err:
+ fdput(f);
+ return ret;
+}
+#endif /* CONFIG_PROC_FS */
+
static int
do_send_specific(pid_t tgid, pid_t pid, int sig, struct kernel_siginfo *info)
{
diff --git a/kernel/sys_ni.c b/kernel/sys_ni.c
index ab9d0e3c6d50..f905f4f9f677 100644
--- a/kernel/sys_ni.c
+++ b/kernel/sys_ni.c
@@ -163,6 +163,7 @@ COND_SYSCALL(syslog);
/* kernel/sched/core.c */
/* kernel/signal.c */
+COND_SYSCALL(pidfd_send_signal);
/* kernel/sys.c */
COND_SYSCALL(setregid);
diff --git a/tools/testing/selftests/Makefile b/tools/testing/selftests/Makefile
index a8ba662da827..6aaa596d13e8 100644
--- a/tools/testing/selftests/Makefile
+++ b/tools/testing/selftests/Makefile
@@ -31,6 +31,7 @@ TARGETS += net
TARGETS += netfilter
TARGETS += networking/timestamping
TARGETS += nsfs
+TARGETS += pidfd
TARGETS += powerpc
TARGETS += proc
TARGETS += pstore
diff --git a/tools/testing/selftests/pidfd/Makefile b/tools/testing/selftests/pidfd/Makefile
new file mode 100644
index 000000000000..deaf8073bc06
--- /dev/null
+++ b/tools/testing/selftests/pidfd/Makefile
@@ -0,0 +1,6 @@
+CFLAGS += -g -I../../../../usr/include/
+
+TEST_GEN_PROGS := pidfd_test
+
+include ../lib.mk
+
diff --git a/tools/testing/selftests/pidfd/pidfd_test.c b/tools/testing/selftests/pidfd/pidfd_test.c
new file mode 100644
index 000000000000..d59378a93782
--- /dev/null
+++ b/tools/testing/selftests/pidfd/pidfd_test.c
@@ -0,0 +1,381 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+
+#define _GNU_SOURCE
+#include <errno.h>
+#include <fcntl.h>
+#include <linux/types.h>
+#include <sched.h>
+#include <signal.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <syscall.h>
+#include <sys/mount.h>
+#include <sys/wait.h>
+#include <unistd.h>
+
+#include "../kselftest.h"
+
+static inline int sys_pidfd_send_signal(int pidfd, int sig, siginfo_t *info,
+ unsigned int flags)
+{
+ return syscall(__NR_pidfd_send_signal, pidfd, sig, info, flags);
+}
+
+static int signal_received;
+
+static void set_signal_received_on_sigusr1(int sig)
+{
+ if (sig == SIGUSR1)
+ signal_received = 1;
+}
+
+/*
+ * Straightforward test to see whether pidfd_send_signal() works is to send
+ * a signal to ourself.
+ */
+static int test_pidfd_send_signal_simple_success(void)
+{
+ int pidfd, ret;
+ const char *test_name = "pidfd_send_signal send SIGUSR1";
+
+ 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);
+
+ signal(SIGUSR1, set_signal_received_on_sigusr1);
+
+ 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",
+ test_name);
+
+ if (signal_received != 1)
+ ksft_exit_fail_msg("%s test: Failed to receive signal\n",
+ test_name);
+
+ signal_received = 0;
+ ksft_test_result_pass("%s test: Sent signal\n", test_name);
+ return 0;
+}
+
+static int wait_for_pid(pid_t pid)
+{
+ int status, ret;
+
+again:
+ ret = waitpid(pid, &status, 0);
+ if (ret == -1) {
+ if (errno == EINTR)
+ goto again;
+
+ return -1;
+ }
+
+ if (ret != pid)
+ goto again;
+
+ if (!WIFEXITED(status))
+ return -1;
+
+ return WEXITSTATUS(status);
+}
+
+static int test_pidfd_send_signal_exited_fail(void)
+{
+ int pidfd, ret, saved_errno;
+ char buf[256];
+ pid_t pid;
+ const char *test_name = "pidfd_send_signal signal exited process";
+
+ pid = fork();
+ if (pid < 0)
+ ksft_exit_fail_msg("%s test: Failed to create new process\n",
+ test_name);
+
+ if (pid == 0)
+ _exit(EXIT_SUCCESS);
+
+ snprintf(buf, sizeof(buf), "/proc/%d", pid);
+
+ pidfd = open(buf, O_DIRECTORY | O_CLOEXEC);
+
+ (void)wait_for_pid(pid);
+
+ if (pidfd < 0)
+ ksft_exit_fail_msg(
+ "%s test: Failed to open process file descriptor\n",
+ test_name);
+
+ ret = sys_pidfd_send_signal(pidfd, 0, NULL, 0);
+ saved_errno = errno;
+ close(pidfd);
+ if (ret == 0)
+ ksft_exit_fail_msg(
+ "%s test: Managed to send signal to process even though it should have failed\n",
+ test_name);
+
+ if (saved_errno != ESRCH)
+ ksft_exit_fail_msg(
+ "%s test: Expected to receive ESRCH as errno value but received %d instead\n",
+ test_name, saved_errno);
+
+ ksft_test_result_pass("%s test: Failed to send signal as expected\n",
+ test_name);
+ return 0;
+}
+
+/*
+ * The kernel reserves 300 pids via RESERVED_PIDS in kernel/pid.c
+ * That means, when it wraps around any pid < 300 will be skipped.
+ * So we need to use a pid > 300 in order to test recycling.
+ */
+#define PID_RECYCLE 1000
+
+/*
+ * Maximum number of cycles we allow. This is equivalent to PID_MAX_DEFAULT.
+ * If users set a higher limit or we have cycled PIDFD_MAX_DEFAULT number of
+ * times then we skip the test to not go into an infinite loop or block for a
+ * long time.
+ */
+#define PIDFD_MAX_DEFAULT 0x8000
+
+/*
+ * Define a few custom error codes for the child process to clearly indicate
+ * what is happening. This way we can tell the difference between a system
+ * error, a test error, etc.
+ */
+#define PIDFD_PASS 0
+#define PIDFD_FAIL 1
+#define PIDFD_ERROR 2
+#define PIDFD_SKIP 3
+#define PIDFD_XFAIL 4
+
+static int test_pidfd_send_signal_recycled_pid_fail(void)
+{
+ int i, ret;
+ pid_t pid1;
+ const char *test_name = "pidfd_send_signal signal recycled pid";
+
+ ret = unshare(CLONE_NEWPID);
+ if (ret < 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);
+
+ ret = mount(NULL, "/", NULL, MS_REC | MS_PRIVATE, 0);
+ if (ret < 0)
+ ksft_exit_fail_msg("%s test: Failed to remount / private\n",
+ test_name);
+
+ /* pid 1 in new pid namespace */
+ pid1 = fork();
+ if (pid1 < 0)
+ ksft_exit_fail_msg("%s test: Failed to create new process\n",
+ test_name);
+
+ if (pid1 == 0) {
+ char buf[256];
+ pid_t pid2;
+ int pidfd = -1;
+
+ (void)umount2("/proc", MNT_DETACH);
+ ret = mount("proc", "/proc", "proc", 0, NULL);
+ if (ret < 0)
+ _exit(PIDFD_ERROR);
+
+ /* grab pid PID_RECYCLE */
+ for (i = 0; i <= PIDFD_MAX_DEFAULT; i++) {
+ pid2 = fork();
+ if (pid2 < 0)
+ _exit(PIDFD_ERROR);
+
+ if (pid2 == 0)
+ _exit(PIDFD_PASS);
+
+ if (pid2 == PID_RECYCLE) {
+ snprintf(buf, sizeof(buf), "/proc/%d", pid2);
+ ksft_print_msg("pid to recycle is %d\n", pid2);
+ pidfd = open(buf, O_DIRECTORY | O_CLOEXEC);
+ }
+
+ if (wait_for_pid(pid2))
+ _exit(PIDFD_ERROR);
+
+ if (pid2 >= PID_RECYCLE)
+ break;
+ }
+
+ /*
+ * We want to be as predictable as we can so if we haven't been
+ * able to grab pid PID_RECYCLE skip the test.
+ */
+ if (pid2 != PID_RECYCLE) {
+ /* skip test */
+ close(pidfd);
+ _exit(PIDFD_SKIP);
+ }
+
+ if (pidfd < 0)
+ _exit(PIDFD_ERROR);
+
+ for (i = 0; i <= PIDFD_MAX_DEFAULT; i++) {
+ char c;
+ int pipe_fds[2];
+ pid_t recycled_pid;
+ int child_ret = PIDFD_PASS;
+
+ ret = pipe2(pipe_fds, O_CLOEXEC);
+ if (ret < 0)
+ _exit(PIDFD_ERROR);
+
+ recycled_pid = fork();
+ if (recycled_pid < 0)
+ _exit(PIDFD_ERROR);
+
+ if (recycled_pid == 0) {
+ close(pipe_fds[1]);
+ (void)read(pipe_fds[0], &c, 1);
+ close(pipe_fds[0]);
+
+ _exit(PIDFD_PASS);
+ }
+
+ /*
+ * Stop the child so we can inspect whether we have
+ * recycled pid PID_RECYCLE.
+ */
+ close(pipe_fds[0]);
+ ret = kill(recycled_pid, SIGSTOP);
+ close(pipe_fds[1]);
+ if (ret) {
+ (void)wait_for_pid(recycled_pid);
+ _exit(PIDFD_ERROR);
+ }
+
+ /*
+ * We have recycled the pid. Try to signal it. This
+ * needs to fail since this is a different process than
+ * the one the pidfd refers to.
+ */
+ if (recycled_pid == PID_RECYCLE) {
+ ret = sys_pidfd_send_signal(pidfd, SIGCONT,
+ NULL, 0);
+ if (ret && errno == ESRCH)
+ child_ret = PIDFD_XFAIL;
+ else
+ child_ret = PIDFD_FAIL;
+ }
+
+ /* let the process move on */
+ ret = kill(recycled_pid, SIGCONT);
+ if (ret)
+ (void)kill(recycled_pid, SIGKILL);
+
+ if (wait_for_pid(recycled_pid))
+ _exit(PIDFD_ERROR);
+
+ switch (child_ret) {
+ case PIDFD_FAIL:
+ /* fallthrough */
+ case PIDFD_XFAIL:
+ _exit(child_ret);
+ case PIDFD_PASS:
+ break;
+ default:
+ /* not reached */
+ _exit(PIDFD_ERROR);
+ }
+
+ /*
+ * If the user set a custom pid_max limit we could be
+ * in the millions.
+ * Skip the test in this case.
+ */
+ if (recycled_pid > PIDFD_MAX_DEFAULT)
+ _exit(PIDFD_SKIP);
+ }
+
+ /* failed to recycle pid */
+ _exit(PIDFD_SKIP);
+ }
+
+ ret = wait_for_pid(pid1);
+ switch (ret) {
+ case PIDFD_FAIL:
+ ksft_exit_fail_msg(
+ "%s test: Managed to signal recycled pid %d\n",
+ test_name, PID_RECYCLE);
+ case PIDFD_PASS:
+ 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);
+ ret = 0;
+ break;
+ case PIDFD_XFAIL:
+ ksft_test_result_pass(
+ "%s test: Failed to signal recycled pid as expected\n",
+ test_name);
+ ret = 0;
+ break;
+ default /* PIDFD_ERROR */:
+ ksft_exit_fail_msg("%s test: Error while running tests\n",
+ test_name);
+ }
+
+ return ret;
+}
+
+static int test_pidfd_send_signal_syscall_support(void)
+{
+ int pidfd, ret;
+ const char *test_name = "pidfd_send_signal check for support";
+
+ 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);
+
+ ret = sys_pidfd_send_signal(pidfd, 0, NULL, 0);
+ if (ret < 0) {
+ /*
+ * pidfd_send_signal() will currently return ENOSYS when
+ * CONFIG_PROC_FS is not set.
+ */
+ if (errno == ENOSYS)
+ ksft_exit_skip(
+ "%s test: pidfd_send_signal() syscall not supported (Ensure that CONFIG_PROC_FS=y is set)\n",
+ test_name);
+
+ ksft_exit_fail_msg("%s test: Failed to send signal\n",
+ test_name);
+ }
+
+ close(pidfd);
+ ksft_test_result_pass(
+ "%s test: pidfd_send_signal() syscall is supported. Tests can be executed\n",
+ test_name);
+ return 0;
+}
+
+int main(int argc, char **argv)
+{
+ ksft_print_header();
+
+ test_pidfd_send_signal_syscall_support();
+ test_pidfd_send_signal_simple_success();
+ test_pidfd_send_signal_exited_fail();
+ test_pidfd_send_signal_recycled_pid_fail();
+
+ return ksft_exit_pass();
+}