Add tests for pidfd_wait() and CLONE_WAIT_PID: - test that pidfd_wait() syscall is supported - test that pidfd_wait() does not accept unknown flags - test that pidfd_wait() can wait on a pidfd - test that pidfd_wait() can wait on a pidfd and return struct rusage - test that pidfd_wait() can wait on a pidfd and return siginfo_t - test that pidfd_wait() works with WEXITED - test that pidfd_wait() works with WSTOPPED - test that pidfd_wait() works with WUNTRACED - test that pidfd_wait() works with WCONTINUED - test that pidfd_wait() works with WNOWAIT - test that pidfd_wait() works with WNOHANG - test that CLONE_WAIT_PID does not appear in waitid(P_ALL) requests - test that CLONE_WAIT_PID does not appear in waitid(P_PGID) requests - test that CLONE_WAIT_PID does not appear in wait4(-1) requests - test that CLONE_WAIT_PID does not appear in wait4(0) requests - test that CLONE_WAIT_PID does appear in waitid(P_PID) requests - test that CLONE_WAIT_PID does appear in wait4(pid) requests
Signed-off-by: Christian Brauner christian@brauner.io Cc: Arnd Bergmann arnd@arndb.de Cc: "Eric W. Biederman" ebiederm@xmission.com Cc: Kees Cook keescook@chromium.org Cc: Joel Fernandes (Google) joel@joelfernandes.org Cc: Thomas Gleixner tglx@linutronix.de Cc: David Howells dhowells@redhat.com Cc: Jann Horn jannh@google.com Cc: Shuah Khan shuah@kernel.org Cc: Andy Lutomirsky luto@kernel.org Cc: Andrew Morton akpm@linux-foundation.org Cc: Oleg Nesterov oleg@redhat.com Cc: Aleksa Sarai cyphar@cyphar.com Cc: Linus Torvalds torvalds@linux-foundation.org Cc: Al Viro viro@zeniv.linux.org.uk Cc: linux-kselftest@vger.kernel.org --- tools/testing/selftests/pidfd/pidfd.h | 25 ++ tools/testing/selftests/pidfd/pidfd_test.c | 14 - tools/testing/selftests/pidfd/pidfd_wait.c | 398 +++++++++++++++++++++ 3 files changed, 423 insertions(+), 14 deletions(-) create mode 100644 tools/testing/selftests/pidfd/pidfd_wait.c
diff --git a/tools/testing/selftests/pidfd/pidfd.h b/tools/testing/selftests/pidfd/pidfd.h index 8452e910463f..d56bca179b9e 100644 --- a/tools/testing/selftests/pidfd/pidfd.h +++ b/tools/testing/selftests/pidfd/pidfd.h @@ -16,6 +16,26 @@
#include "../kselftest.h"
+#ifndef CLONE_PIDFD +#define CLONE_PIDFD 0x00001000 +#endif + +#ifndef CLONE_WAIT_PID +#define CLONE_WAIT_PID 0x200000000ULL +#endif + +#ifndef __NR_pidfd_open +#define __NR_pidfd_open -1 +#endif + +#ifndef __NR_pidfd_send_signal +#define __NR_pidfd_send_signal -1 +#endif + +#ifndef __NR_clone3 +#define __NR_clone3 -1 +#endif + /* * The kernel reserves 300 pids via RESERVED_PIDS in kernel/pid.c * That means, when it wraps around any pid < 300 will be skipped. @@ -53,5 +73,10 @@ int wait_for_pid(pid_t pid) return WEXITSTATUS(status); }
+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); +}
#endif /* __PIDFD_H */ diff --git a/tools/testing/selftests/pidfd/pidfd_test.c b/tools/testing/selftests/pidfd/pidfd_test.c index 7eaa8a3de262..42e3eb494d72 100644 --- a/tools/testing/selftests/pidfd/pidfd_test.c +++ b/tools/testing/selftests/pidfd/pidfd_test.c @@ -21,20 +21,12 @@ #include "pidfd.h" #include "../kselftest.h"
-#ifndef __NR_pidfd_send_signal -#define __NR_pidfd_send_signal -1 -#endif - #define str(s) _str(s) #define _str(s) #s #define CHILD_THREAD_MIN_WAIT 3 /* seconds */
#define MAX_EVENTS 5
-#ifndef CLONE_PIDFD -#define CLONE_PIDFD 0x00001000 -#endif - static pid_t pidfd_clone(int flags, int *pidfd, int (*fn)(void *)) { size_t stack_size = 1024; @@ -47,12 +39,6 @@ static pid_t pidfd_clone(int flags, int *pidfd, int (*fn)(void *)) #endif }
-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) diff --git a/tools/testing/selftests/pidfd/pidfd_wait.c b/tools/testing/selftests/pidfd/pidfd_wait.c new file mode 100644 index 000000000000..fcbd10098067 --- /dev/null +++ b/tools/testing/selftests/pidfd/pidfd_wait.c @@ -0,0 +1,398 @@ +/* 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.h" + +#define ptr_to_u64(ptr) ((__u64)((uintptr_t)(ptr))) + +static pid_t sys_clone3(struct clone_args *args) +{ + return syscall(__NR_clone3, args, sizeof(struct clone_args)); +} + +static pid_t sys_pidfd_wait(int pidfd, int *wstatus, siginfo_t *info, + struct rusage *ru, unsigned int states, + unsigned int flags) +{ + return syscall(__NR_pidfd_wait, pidfd, wstatus, info, ru, states, flags); +} + +static int test_pidfd_wait_syscall_support(void) +{ + int ret; + const char *test_name = "pidfd_wait check for support"; + + ret = sys_pidfd_wait(-EBADF, NULL, NULL, NULL, WEXITED, 0); + if (ret < 0 && errno == ENOSYS) + ksft_exit_skip("%s test: pidfd_wait() syscall not supported\n", + test_name); + + ksft_test_result_pass("%s test: Passed\n", test_name); + return 0; +} + +static int test_pidfd_wait_simple(void) +{ + const char *test_name = "pidfd_wait simple"; + int pidfd = -1, status = 0; + 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; + + pid = sys_clone3(&args); + if (pid < 0) + ksft_exit_fail_msg("%s test: failed to create new process %s", + test_name, strerror(errno)); + + if (pid == 0) + exit(EXIT_SUCCESS); + + pid = sys_pidfd_wait(pidfd, NULL, NULL, NULL, -1, 0); + if (pid > 0) + ksft_exit_fail_msg( + "%s test: succeeded to wait on process with invalid flags passed", + test_name); + + pid = sys_pidfd_wait(pidfd, NULL, NULL, NULL, 0, -1); + if (pid > 0) + ksft_exit_fail_msg( + "%s test: succeeded to wait on process with invalid flags passed", + test_name); + + pid = sys_pidfd_wait(pidfd, NULL, NULL, NULL, 0, 0); + if (pid > 0) + ksft_exit_fail_msg( + "%s test: succeeded to wait on process with invalid flags passed", + test_name); + + pid = sys_pidfd_wait(pidfd, NULL, NULL, NULL, WEXITED, 0); + if (pid < 0) + ksft_exit_fail_msg( + "%s test: failed to wait on process with pid %d and pidfd %d: %s", + test_name, parent_tid, pidfd, strerror(errno)); + close(pidfd); + + pidfd = -1; + parent_tid = -1; + pid = sys_clone3(&args); + if (pid < 0) + ksft_exit_fail_msg("%s test: failed to create new process %s", + test_name, strerror(errno)); + + if (pid == 0) + exit(EXIT_SUCCESS); + + pid = sys_pidfd_wait(pidfd, &status, NULL, NULL, WEXITED, 0); + if (pid < 0) + ksft_exit_fail_msg( + "%s test: failed to wait on process with pid %d and pidfd %d: %s", + test_name, parent_tid, pidfd, strerror(errno)); + + if (!WIFEXITED(status) || WEXITSTATUS(status)) + ksft_exit_fail_msg( + "%s test: unexpected status received after waiting on process with pid %d and pidfd %d: %s", + test_name, parent_tid, pidfd, strerror(errno)); + close(pidfd); + + pidfd = -1; + parent_tid = -1; + pid = sys_clone3(&args); + if (pid < 0) + ksft_exit_fail_msg("%s test: failed to create new process %s", + test_name, strerror(errno)); + + if (pid == 0) + exit(EXIT_FAILURE); + + pid = sys_pidfd_wait(pidfd, &status, NULL, NULL, WEXITED, 0); + if (pid < 0) + ksft_exit_fail_msg( + "%s test: failed to wait on process with pid %d and pidfd %d: %s", + test_name, parent_tid, pidfd, strerror(errno)); + + if (!WIFEXITED(status) || !WEXITSTATUS(status)) + ksft_exit_fail_msg( + "%s test: unexpected status received after waiting on process with pid %d and pidfd %d: %s", + test_name, parent_tid, pidfd, strerror(errno)); + close(pidfd); + + ksft_test_result_pass("%s test: Passed\n", test_name); + return 0; +} + +static int test_pidfd_wait_rusage(void) +{ + const char *test_name = "pidfd_wait rusage"; + int pidfd = -1, status = 0; + 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; + struct rusage rusage = { 0 }; + + pid = sys_clone3(&args); + if (pid < 0) + ksft_exit_fail_msg("%s test: failed to create new process %s", + test_name, strerror(errno)); + + if (pid == 0) + exit(EXIT_SUCCESS); + + pid = sys_pidfd_wait(pidfd, &status, NULL, &rusage, WEXITED, 0); + if (pid < 0) + ksft_exit_fail_msg( + "%s test: failed to wait on process with pid %d and pidfd %d: %s", + test_name, parent_tid, pidfd, strerror(errno)); + + if (!WIFEXITED(status) || WEXITSTATUS(status)) + ksft_exit_fail_msg( + "%s test: unexpected status received after waiting on process with pid %d and pidfd %d: %s", + test_name, parent_tid, pidfd, strerror(errno)); + close(pidfd); + + ksft_test_result_pass("%s test: Passed\n", test_name); + return 0; +} + +static int test_pidfd_wait_siginfo(void) +{ + const char *test_name = "pidfd_wait siginfo"; + int pidfd = -1, status = 0; + 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, + }; + + pid = sys_clone3(&args); + if (pid < 0) + ksft_exit_fail_msg("%s test: failed to create new process %s", + test_name, strerror(errno)); + + if (pid == 0) + exit(EXIT_SUCCESS); + + pid = sys_pidfd_wait(pidfd, &status, &info, NULL, WEXITED, 0); + if (pid < 0) + ksft_exit_fail_msg( + "%s test: failed to wait on process with pid %d and pidfd %d: %s", + test_name, parent_tid, pidfd, strerror(errno)); + + if (!WIFEXITED(status) || WEXITSTATUS(status)) + ksft_exit_fail_msg( + "%s test: unexpected status received after waiting on process with pid %d and pidfd %d: %s", + test_name, parent_tid, pidfd, strerror(errno)); + close(pidfd); + + if (info.si_signo != SIGCHLD) + ksft_exit_fail_msg( + "%s test: unexpected si_signo value %d received after waiting on process with pid %d and pidfd %d: %s", + test_name, info.si_signo, parent_tid, pidfd, + strerror(errno)); + + if (info.si_code != CLD_EXITED) + ksft_exit_fail_msg( + "%s test: unexpected si_code value %d received after waiting on process with pid %d and pidfd %d: %s", + test_name, info.si_code, parent_tid, pidfd, + strerror(errno)); + + ksft_test_result_pass("%s test: Passed\n", test_name); + return 0; +} + +static int test_pidfd_wait_states(void) +{ + const char *test_name = "pidfd_wait states"; + int pidfd = -1, status = 0; + 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 ret; + pid_t pid; + siginfo_t info = { + .si_signo = 0, + }; + + pid = sys_clone3(&args); + if (pid < 0) + ksft_exit_fail_msg("%s test: failed to create new process %s", + test_name, strerror(errno)); + + if (pid == 0) { + kill(getpid(), SIGSTOP); + kill(getpid(), SIGSTOP); + exit(EXIT_SUCCESS); + } + + pid = sys_pidfd_wait(pidfd, &status, &info, NULL, WSTOPPED, 0); + if (pid < 0) + ksft_exit_fail_msg( + "%s test: failed to wait on process with pid %d and pidfd %d: %s", + test_name, parent_tid, pidfd, strerror(errno)); + + ret = sys_pidfd_send_signal(pidfd, SIGCONT, NULL, 0); + if (ret < 0) + ksft_exit_fail_msg( + "%s test: failed to wait on process with pid %d and pidfd %d: %s", + test_name, parent_tid, pidfd, strerror(errno)); + + pid = sys_pidfd_wait(pidfd, &status, &info, NULL, WCONTINUED, 0); + if (pid < 0) + ksft_exit_fail_msg( + "%s test: failed to wait on process with pid %d and pidfd %d: %s", + test_name, parent_tid, pidfd, strerror(errno)); + + pid = sys_pidfd_wait(pidfd, &status, &info, NULL, WUNTRACED, 0); + if (pid < 0) + ksft_exit_fail_msg( + "%s test: failed to wait on process with pid %d and pidfd %d: %s", + test_name, parent_tid, pidfd, strerror(errno)); + + ret = sys_pidfd_send_signal(pidfd, SIGKILL, NULL, 0); + if (ret < 0) + ksft_exit_fail_msg( + "%s test: failed to wait on process with pid %d and pidfd %d: %s", + test_name, parent_tid, pidfd, strerror(errno)); + + pid = sys_pidfd_wait(pidfd, &status, &info, NULL, WEXITED, 0); + if (pid < 0) + ksft_exit_fail_msg( + "%s test: failed to wait on process with pid %d and pidfd %d: %s", + test_name, parent_tid, pidfd, strerror(errno)); + + close(pidfd); + + ksft_test_result_pass("%s test: Passed\n", test_name); + return 0; +} + +static int test_clone_wait_pid(void) +{ + const char *test_name = "CLONE_WAIT_PID"; + int pidfd = -1, status = 0; + pid_t parent_tid = -1; + struct clone_args args = { + .parent_tid = ptr_to_u64(&parent_tid), + .pidfd = ptr_to_u64(&pidfd), + .flags = CLONE_PARENT_SETTID | CLONE_WAIT_PID, + .exit_signal = SIGCHLD, + }; + int ret; + pid_t pid, rpid; + + pid = sys_clone3(&args); + if (pid > 0) + ksft_exit_fail_msg( + "%s test: managed to create new process with CLONE_WAIT_PID but without CLONE_PIDFD", + test_name); + + args.flags |= CLONE_PIDFD; + pid = sys_clone3(&args); + if (pid < 0) + ksft_exit_fail_msg("%s test: failed to create new process %s", + test_name, strerror(errno)); + + if (pid == 0) + exit(EXIT_SUCCESS); + + ret = syscall(__NR_waitid, P_ALL, -1, NULL, WEXITED, NULL); + if (ret == 0) + ksft_exit_fail_msg( + "%s test: managed to wait on process created with CLONE_PIDFD | CLONE_WAIT_PID with pid %d and pidfd %d through waitid(P_ALL) request", + test_name, parent_tid, pidfd); + + ret = syscall(__NR_waitid, P_PGID, getpgid(0), NULL, WEXITED, NULL); + if (ret == 0) + ksft_exit_fail_msg( + "%s test: managed to wait on process created with CLONE_PIDFD | CLONE_WAIT_PID with pid %d and pidfd %d through waitid(P_PGID) request", + test_name, parent_tid, pidfd); + + rpid = syscall(__NR_wait4, -1, NULL, 0, NULL); + if (rpid > 0) + ksft_exit_fail_msg( + "%s test: managed to wait on process created with CLONE_PIDFD | CLONE_WAIT_PID with pid %d and pidfd %d through wait4(-1) request", + test_name, parent_tid, pidfd); + + rpid = syscall(__NR_wait4, 0, NULL, 0, NULL); + if (rpid > 0) + ksft_exit_fail_msg( + "%s test: managed to wait on process created with CLONE_PIDFD | CLONE_WAIT_PID with pid %d and pidfd %d through wait4(0) request", + test_name, parent_tid, pidfd); + + ret = syscall(__NR_waitid, P_PID, pid, NULL, WEXITED | WNOWAIT | WNOHANG, NULL); + if (ret < 0) + ksft_exit_fail_msg( + "%s test: failed to wait on process created with CLONE_PIDFD | CLONE_WAIT_PID with pid %d and pidfd %d through waitid(P_PID) request: %s", + test_name, parent_tid, pidfd, strerror(errno)); + + rpid = sys_pidfd_wait(pidfd, NULL, NULL, NULL, WEXITED, WNOWAIT | WNOHANG); + if (rpid < 0) + ksft_exit_fail_msg( + "%s test: failed to wait on process with pid %d and pidfd %d: %s", + test_name, parent_tid, pidfd, strerror(errno)); + + rpid = syscall(__NR_wait4, pid, &status, 0, NULL); + if (rpid < 0) + ksft_exit_fail_msg( + "%s test: failed to wait on process created with CLONE_PIDFD | CLONE_WAIT_PID with pid %d and pidfd %d through wait4(%d) request: %s", + test_name, parent_tid, pidfd, parent_tid, strerror(errno)); + + if (!WIFEXITED(status) || WEXITSTATUS(status)) + ksft_exit_fail_msg( + "%s test: unexpected status received after waiting on process with pid %d and pidfd %d: %s", + test_name, parent_tid, pidfd, strerror(errno)); + close(pidfd); + + ksft_test_result_pass("%s test: Passed\n", test_name); + return 0; +} + +int main(int argc, char **argv) +{ + ksft_print_header(); + ksft_set_plan(6); + + test_pidfd_wait_syscall_support(); + test_pidfd_wait_simple(); + test_pidfd_wait_rusage(); + test_pidfd_wait_siginfo(); + test_pidfd_wait_states(); + test_clone_wait_pid(); + + return ksft_exit_pass(); +}