diff options
Diffstat (limited to 'tools/testing/selftests/pidfd/pidfd_wait.c')
| -rw-r--r-- | tools/testing/selftests/pidfd/pidfd_wait.c | 222 |
1 files changed, 222 insertions, 0 deletions
diff --git a/tools/testing/selftests/pidfd/pidfd_wait.c b/tools/testing/selftests/pidfd/pidfd_wait.c new file mode 100644 index 000000000000..4bf702d62c1c --- /dev/null +++ b/tools/testing/selftests/pidfd/pidfd_wait.c @@ -0,0 +1,222 @@ +/* SPDX-License-Identifier: GPL-2.0 */ + +#define _GNU_SOURCE +#include <errno.h> +#include <linux/sched.h> +#include <linux/types.h> +#include <signal.h> +#include <stdint.h> +#include <stdio.h> +#include <stdlib.h> +#include <sched.h> +#include <string.h> +#include <sys/resource.h> +#include <sys/time.h> +#include <sys/types.h> +#include <sys/wait.h> +#include <unistd.h> + +#include "pidfd.h" +#include "kselftest_harness.h" + +#define ptr_to_u64(ptr) ((__u64)((uintptr_t)(ptr))) + +/* Attempt to de-conflict with the selftests tree. */ +#ifndef SKIP +#define SKIP(s, ...) XFAIL(s, ##__VA_ARGS__) +#endif + +TEST(wait_simple) +{ + int pidfd = -1; + pid_t parent_tid = -1; + struct __clone_args args = { + .parent_tid = ptr_to_u64(&parent_tid), + .pidfd = ptr_to_u64(&pidfd), + .flags = CLONE_PIDFD | CLONE_PARENT_SETTID, + .exit_signal = SIGCHLD, + }; + pid_t pid; + siginfo_t info = { + .si_signo = 0, + }; + + pidfd = open("/proc/self", O_DIRECTORY | O_RDONLY | O_CLOEXEC); + ASSERT_GE(pidfd, 0); + + pid = sys_waitid(P_PIDFD, pidfd, &info, WEXITED); + ASSERT_NE(pid, 0); + EXPECT_EQ(close(pidfd), 0); + pidfd = -1; + + pidfd = open("/dev/null", O_RDONLY | O_CLOEXEC); + ASSERT_GE(pidfd, 0); + + pid = sys_waitid(P_PIDFD, pidfd, &info, WEXITED); + ASSERT_NE(pid, 0); + EXPECT_EQ(close(pidfd), 0); + pidfd = -1; + + pid = sys_clone3(&args, sizeof(args)); + ASSERT_GE(pid, 0); + + if (pid == 0) + exit(EXIT_SUCCESS); + + pid = sys_waitid(P_PIDFD, pidfd, &info, WEXITED); + ASSERT_GE(pid, 0); + ASSERT_EQ(WIFEXITED(info.si_status), true); + ASSERT_EQ(WEXITSTATUS(info.si_status), 0); + EXPECT_EQ(close(pidfd), 0); + + ASSERT_EQ(info.si_signo, SIGCHLD); + ASSERT_EQ(info.si_code, CLD_EXITED); + ASSERT_EQ(info.si_pid, parent_tid); +} + +TEST(wait_states) +{ + int pidfd = -1; + pid_t parent_tid = -1; + struct __clone_args args = { + .parent_tid = ptr_to_u64(&parent_tid), + .pidfd = ptr_to_u64(&pidfd), + .flags = CLONE_PIDFD | CLONE_PARENT_SETTID, + .exit_signal = SIGCHLD, + }; + int pfd[2]; + pid_t pid; + siginfo_t info = { + .si_signo = 0, + }; + + ASSERT_EQ(pipe(pfd), 0); + pid = sys_clone3(&args, sizeof(args)); + ASSERT_GE(pid, 0); + + if (pid == 0) { + char buf[2]; + + close(pfd[1]); + kill(getpid(), SIGSTOP); + ASSERT_EQ(read(pfd[0], buf, 1), 1); + close(pfd[0]); + kill(getpid(), SIGSTOP); + exit(EXIT_SUCCESS); + } + + close(pfd[0]); + ASSERT_EQ(sys_waitid(P_PIDFD, pidfd, &info, WSTOPPED), 0); + ASSERT_EQ(info.si_signo, SIGCHLD); + ASSERT_EQ(info.si_code, CLD_STOPPED); + ASSERT_EQ(info.si_pid, parent_tid); + + ASSERT_EQ(sys_pidfd_send_signal(pidfd, SIGCONT, NULL, 0), 0); + + ASSERT_EQ(sys_waitid(P_PIDFD, pidfd, &info, WCONTINUED), 0); + ASSERT_EQ(write(pfd[1], "C", 1), 1); + close(pfd[1]); + ASSERT_EQ(info.si_signo, SIGCHLD); + ASSERT_EQ(info.si_code, CLD_CONTINUED); + ASSERT_EQ(info.si_pid, parent_tid); + + ASSERT_EQ(sys_waitid(P_PIDFD, pidfd, &info, WUNTRACED), 0); + ASSERT_EQ(info.si_signo, SIGCHLD); + ASSERT_EQ(info.si_code, CLD_STOPPED); + ASSERT_EQ(info.si_pid, parent_tid); + + ASSERT_EQ(sys_pidfd_send_signal(pidfd, SIGKILL, NULL, 0), 0); + + ASSERT_EQ(sys_waitid(P_PIDFD, pidfd, &info, WEXITED), 0); + ASSERT_EQ(info.si_signo, SIGCHLD); + ASSERT_EQ(info.si_code, CLD_KILLED); + ASSERT_EQ(info.si_pid, parent_tid); + + EXPECT_EQ(close(pidfd), 0); +} + +TEST(wait_nonblock) +{ + int pidfd; + unsigned int flags = 0; + pid_t parent_tid = -1; + struct __clone_args args = { + .parent_tid = ptr_to_u64(&parent_tid), + .flags = CLONE_PARENT_SETTID, + .exit_signal = SIGCHLD, + }; + int ret; + pid_t pid; + siginfo_t info = { + .si_signo = 0, + }; + + /* + * Callers need to see ECHILD with non-blocking pidfds when no child + * processes exists. + */ + pidfd = sys_pidfd_open(getpid(), PIDFD_NONBLOCK); + EXPECT_GE(pidfd, 0) { + /* pidfd_open() doesn't support PIDFD_NONBLOCK. */ + ASSERT_EQ(errno, EINVAL); + SKIP(return, "Skipping PIDFD_NONBLOCK test"); + } + + ret = sys_waitid(P_PIDFD, pidfd, &info, WEXITED); + ASSERT_LT(ret, 0); + ASSERT_EQ(errno, ECHILD); + EXPECT_EQ(close(pidfd), 0); + + pid = sys_clone3(&args, sizeof(args)); + ASSERT_GE(pid, 0); + + if (pid == 0) { + kill(getpid(), SIGSTOP); + exit(EXIT_SUCCESS); + } + + pidfd = sys_pidfd_open(pid, PIDFD_NONBLOCK); + EXPECT_GE(pidfd, 0) { + /* pidfd_open() doesn't support PIDFD_NONBLOCK. */ + ASSERT_EQ(errno, EINVAL); + SKIP(return, "Skipping PIDFD_NONBLOCK test"); + } + + flags = fcntl(pidfd, F_GETFL, 0); + ASSERT_GT(flags, 0); + ASSERT_GT((flags & O_NONBLOCK), 0); + + /* + * Callers need to see EAGAIN/EWOULDBLOCK with non-blocking pidfd when + * child processes exist but none have exited. + */ + ret = sys_waitid(P_PIDFD, pidfd, &info, WEXITED); + ASSERT_LT(ret, 0); + ASSERT_EQ(errno, EAGAIN); + + /* + * Callers need to continue seeing 0 with non-blocking pidfd and + * WNOHANG raised explicitly when child processes exist but none have + * exited. + */ + ret = sys_waitid(P_PIDFD, pidfd, &info, WEXITED | WNOHANG); + ASSERT_EQ(ret, 0); + + ASSERT_EQ(fcntl(pidfd, F_SETFL, (flags & ~O_NONBLOCK)), 0); + + ASSERT_EQ(sys_waitid(P_PIDFD, pidfd, &info, WSTOPPED), 0); + ASSERT_EQ(info.si_signo, SIGCHLD); + ASSERT_EQ(info.si_code, CLD_STOPPED); + ASSERT_EQ(info.si_pid, parent_tid); + + ASSERT_EQ(sys_pidfd_send_signal(pidfd, SIGCONT, NULL, 0), 0); + + ASSERT_EQ(sys_waitid(P_PIDFD, pidfd, &info, WEXITED), 0); + ASSERT_EQ(info.si_signo, SIGCHLD); + ASSERT_EQ(info.si_code, CLD_EXITED); + ASSERT_EQ(info.si_pid, parent_tid); + + EXPECT_EQ(close(pidfd), 0); +} + +TEST_HARNESS_MAIN |