diff options
Diffstat (limited to 'tools/testing/selftests')
-rw-r--r-- | tools/testing/selftests/pidfd/.gitignore | 1 | ||||
-rw-r--r-- | tools/testing/selftests/pidfd/Makefile | 4 | ||||
-rw-r--r-- | tools/testing/selftests/pidfd/pidfd.h | 57 | ||||
-rw-r--r-- | tools/testing/selftests/pidfd/pidfd_open_test.c | 169 | ||||
-rw-r--r-- | tools/testing/selftests/pidfd/pidfd_test.c | 248 |
5 files changed, 437 insertions, 42 deletions
diff --git a/tools/testing/selftests/pidfd/.gitignore b/tools/testing/selftests/pidfd/.gitignore index 822a1e63d045..16d84d117bc0 100644 --- a/tools/testing/selftests/pidfd/.gitignore +++ b/tools/testing/selftests/pidfd/.gitignore @@ -1 +1,2 @@ +pidfd_open_test pidfd_test diff --git a/tools/testing/selftests/pidfd/Makefile b/tools/testing/selftests/pidfd/Makefile index 443fedbd6231..720b2d884b3c 100644 --- a/tools/testing/selftests/pidfd/Makefile +++ b/tools/testing/selftests/pidfd/Makefile @@ -1,7 +1,7 @@ # SPDX-License-Identifier: GPL-2.0-only -CFLAGS += -g -I../../../../usr/include/ +CFLAGS += -g -I../../../../usr/include/ -lpthread -TEST_GEN_PROGS := pidfd_test +TEST_GEN_PROGS := pidfd_test pidfd_open_test include ../lib.mk diff --git a/tools/testing/selftests/pidfd/pidfd.h b/tools/testing/selftests/pidfd/pidfd.h new file mode 100644 index 000000000000..8452e910463f --- /dev/null +++ b/tools/testing/selftests/pidfd/pidfd.h @@ -0,0 +1,57 @@ +/* SPDX-License-Identifier: GPL-2.0 */ + +#ifndef __PIDFD_H +#define __PIDFD_H + +#define _GNU_SOURCE +#include <errno.h> +#include <fcntl.h> +#include <sched.h> +#include <signal.h> +#include <stdio.h> +#include <stdlib.h> +#include <string.h> +#include <syscall.h> +#include <sys/mount.h> + +#include "../kselftest.h" + +/* + * 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 + +/* + * 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 + +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 (!WIFEXITED(status)) + return -1; + + return WEXITSTATUS(status); +} + + +#endif /* __PIDFD_H */ diff --git a/tools/testing/selftests/pidfd/pidfd_open_test.c b/tools/testing/selftests/pidfd/pidfd_open_test.c new file mode 100644 index 000000000000..0377133dd6dc --- /dev/null +++ b/tools/testing/selftests/pidfd/pidfd_open_test.c @@ -0,0 +1,169 @@ +// SPDX-License-Identifier: GPL-2.0 + +#define _GNU_SOURCE +#include <errno.h> +#include <fcntl.h> +#include <inttypes.h> +#include <limits.h> +#include <linux/types.h> +#include <linux/wait.h> +#include <sched.h> +#include <signal.h> +#include <stdbool.h> +#include <stdio.h> +#include <stdlib.h> +#include <string.h> +#include <syscall.h> +#include <sys/mount.h> +#include <sys/prctl.h> +#include <sys/wait.h> +#include <unistd.h> + +#include "pidfd.h" +#include "../kselftest.h" + +static inline int sys_pidfd_open(pid_t pid, unsigned int flags) +{ + return syscall(__NR_pidfd_open, pid, flags); +} + +static int safe_int(const char *numstr, int *converted) +{ + char *err = NULL; + long sli; + + errno = 0; + sli = strtol(numstr, &err, 0); + if (errno == ERANGE && (sli == LONG_MAX || sli == LONG_MIN)) + return -ERANGE; + + if (errno != 0 && sli == 0) + return -EINVAL; + + if (err == numstr || *err != '\0') + return -EINVAL; + + if (sli > INT_MAX || sli < INT_MIN) + return -ERANGE; + + *converted = (int)sli; + return 0; +} + +static int char_left_gc(const char *buffer, size_t len) +{ + size_t i; + + for (i = 0; i < len; i++) { + if (buffer[i] == ' ' || + buffer[i] == '\t') + continue; + + return i; + } + + return 0; +} + +static int char_right_gc(const char *buffer, size_t len) +{ + int i; + + for (i = len - 1; i >= 0; i--) { + if (buffer[i] == ' ' || + buffer[i] == '\t' || + buffer[i] == '\n' || + buffer[i] == '\0') + continue; + + return i + 1; + } + + return 0; +} + +static char *trim_whitespace_in_place(char *buffer) +{ + buffer += char_left_gc(buffer, strlen(buffer)); + buffer[char_right_gc(buffer, strlen(buffer))] = '\0'; + return buffer; +} + +static pid_t get_pid_from_fdinfo_file(int pidfd, const char *key, size_t keylen) +{ + int ret; + char path[512]; + FILE *f; + size_t n = 0; + pid_t result = -1; + char *line = NULL; + + snprintf(path, sizeof(path), "/proc/self/fdinfo/%d", pidfd); + + f = fopen(path, "re"); + if (!f) + return -1; + + while (getline(&line, &n, f) != -1) { + char *numstr; + + if (strncmp(line, key, keylen)) + continue; + + numstr = trim_whitespace_in_place(line + 4); + ret = safe_int(numstr, &result); + if (ret < 0) + goto out; + + break; + } + +out: + free(line); + fclose(f); + return result; +} + +int main(int argc, char **argv) +{ + int pidfd = -1, ret = 1; + pid_t pid; + + ksft_set_plan(3); + + pidfd = sys_pidfd_open(-1, 0); + if (pidfd >= 0) { + ksft_print_msg( + "%s - succeeded to open pidfd for invalid pid -1\n", + strerror(errno)); + goto on_error; + } + ksft_test_result_pass("do not allow invalid pid test: passed\n"); + + pidfd = sys_pidfd_open(getpid(), 1); + if (pidfd >= 0) { + ksft_print_msg( + "%s - succeeded to open pidfd with invalid flag value specified\n", + strerror(errno)); + goto on_error; + } + ksft_test_result_pass("do not allow invalid flag test: passed\n"); + + pidfd = sys_pidfd_open(getpid(), 0); + if (pidfd < 0) { + ksft_print_msg("%s - failed to open pidfd\n", strerror(errno)); + goto on_error; + } + ksft_test_result_pass("open a new pidfd test: passed\n"); + + pid = get_pid_from_fdinfo_file(pidfd, "Pid:", sizeof("Pid:") - 1); + ksft_print_msg("pidfd %d refers to process with pid %d\n", pidfd, pid); + + ret = 0; + +on_error: + if (pidfd >= 0) + close(pidfd); + + return !ret ? ksft_exit_pass() : ksft_exit_fail(); +} diff --git a/tools/testing/selftests/pidfd/pidfd_test.c b/tools/testing/selftests/pidfd/pidfd_test.c index 104c75a33882..7eaa8a3de262 100644 --- a/tools/testing/selftests/pidfd/pidfd_test.c +++ b/tools/testing/selftests/pidfd/pidfd_test.c @@ -4,22 +4,49 @@ #include <errno.h> #include <fcntl.h> #include <linux/types.h> +#include <pthread.h> #include <sched.h> #include <signal.h> #include <stdio.h> #include <stdlib.h> #include <string.h> #include <syscall.h> +#include <sys/epoll.h> +#include <sys/mman.h> #include <sys/mount.h> #include <sys/wait.h> +#include <time.h> #include <unistd.h> +#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; + char *stack[1024] = { 0 }; + +#ifdef __ia64__ + return __clone2(fn, stack, stack_size, flags | SIGCHLD, NULL, pidfd); +#else + return clone(fn, stack + stack_size, flags | SIGCHLD, NULL, pidfd); +#endif +} + static inline int sys_pidfd_send_signal(int pidfd, int sig, siginfo_t *info, unsigned int flags) { @@ -66,28 +93,6 @@ static int test_pidfd_send_signal_simple_success(void) 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; @@ -133,13 +138,6 @@ static int test_pidfd_send_signal_exited_fail(void) } /* - * 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 @@ -147,17 +145,6 @@ static int test_pidfd_send_signal_exited_fail(void) */ #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; @@ -372,11 +359,192 @@ static int test_pidfd_send_signal_syscall_support(void) return 0; } +static void *test_pidfd_poll_exec_thread(void *priv) +{ + ksft_print_msg("Child Thread: starting. pid %d tid %d ; 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", + getpid(), syscall(SYS_gettid)); + return NULL; +} + +static void poll_pidfd(const char *test_name, int pidfd) +{ + int c; + int epoll_fd = epoll_create1(EPOLL_CLOEXEC); + struct epoll_event event, events[MAX_EVENTS]; + + if (epoll_fd == -1) + ksft_exit_fail_msg("%s test: Failed to create epoll file descriptor " + "(errno %d)\n", + test_name, errno); + + event.events = EPOLLIN; + event.data.fd = pidfd; + + if (epoll_ctl(epoll_fd, EPOLL_CTL_ADD, pidfd, &event)) { + ksft_exit_fail_msg("%s test: Failed to add epoll file descriptor " + "(errno %d)\n", + test_name, errno); + } + + 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) ", + "(errno %d)\n", + test_name, c, events[0].events, errno); + + close(epoll_fd); + return; + +} + +static int child_poll_exec_test(void *args) +{ + pthread_t t1; + + ksft_print_msg("Child (pidfd): starting. pid %d tid %d\n", getpid(), + syscall(SYS_gettid)); + pthread_create(&t1, NULL, test_pidfd_poll_exec_thread, NULL); + /* + * Exec in the non-leader thread will destroy the leader immediately. + * If the wait in the parent returns too soon, the test fails. + */ + while (1) + sleep(1); +} + +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"; + + ksft_print_msg("Parent: pid: %d\n", getpid()); + pid = pidfd_clone(CLONE_PIDFD, &pidfd, child_poll_exec_test); + if (pid < 0) + ksft_exit_fail_msg("%s test: pidfd_clone failed (ret %d, errno %d)\n", + test_name, pid, errno); + + ksft_print_msg("Parent: Waiting for Child (%d) to complete.\n", pid); + + if (use_waitpid) { + ret = waitpid(pid, &status, 0); + if (ret == -1) + ksft_print_msg("Parent: error\n"); + + if (ret == pid) + ksft_print_msg("Parent: Child process waited for.\n"); + } else { + poll_pidfd(test_name, pidfd); + } + + time_t prog_time = time(NULL) - prog_start; + + ksft_print_msg("Time waited for child: %lu\n", prog_time); + + close(pidfd); + + if (prog_time < CHILD_THREAD_MIN_WAIT || prog_time > CHILD_THREAD_MIN_WAIT + 2) + ksft_exit_fail_msg("%s test: Failed\n", test_name); + else + ksft_test_result_pass("%s test: Passed\n", test_name); +} + +static void *test_pidfd_poll_leader_exit_thread(void *priv) +{ + ksft_print_msg("Child Thread: starting. pid %d tid %d ; 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)); + return NULL; +} + +static time_t *child_exit_secs; +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)); + 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 + * so that only the group leader exits, leaving the threads alone. + */ + *child_exit_secs = time(NULL); + syscall(SYS_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); + const char *test_name = "pidfd_poll check for premature notification on non-empty" + "group leader exit"; + + child_exit_secs = mmap(NULL, sizeof *child_exit_secs, PROT_READ | PROT_WRITE, + MAP_SHARED | MAP_ANONYMOUS, -1, 0); + + if (child_exit_secs == MAP_FAILED) + ksft_exit_fail_msg("%s test: mmap failed (errno %d)\n", + test_name, errno); + + ksft_print_msg("Parent: pid: %d\n", getpid()); + pid = pidfd_clone(CLONE_PIDFD, &pidfd, child_poll_leader_exit_test); + if (pid < 0) + ksft_exit_fail_msg("%s test: pidfd_clone failed (ret %d, errno %d)\n", + test_name, pid, errno); + + ksft_print_msg("Parent: Waiting for Child (%d) to complete.\n", pid); + + if (use_waitpid) { + ret = waitpid(pid, &status, 0); + if (ret == -1) + ksft_print_msg("Parent: error\n"); + } else { + /* + * This sleep tests for the case where if the child exits, and is in + * EXIT_ZOMBIE, but the thread group leader is non-empty, then the poll + * doesn't prematurely return even though there are active threads + */ + sleep(1); + poll_pidfd(test_name, pidfd); + } + + if (ret == pid) + ksft_print_msg("Parent: Child process waited for.\n"); + + time_t since_child_exit = time(NULL) - *child_exit_secs; + + ksft_print_msg("Time since child exit: %lu\n", since_child_exit); + + close(pidfd); + + if (since_child_exit < CHILD_THREAD_MIN_WAIT || + since_child_exit > CHILD_THREAD_MIN_WAIT + 2) + ksft_exit_fail_msg("%s test: Failed\n", test_name); + else + ksft_test_result_pass("%s test: Passed\n", test_name); +} + int main(int argc, char **argv) { ksft_print_header(); ksft_set_plan(4); + test_pidfd_poll_exec(0); + test_pidfd_poll_exec(1); + test_pidfd_poll_leader_exit(0); + test_pidfd_poll_leader_exit(1); test_pidfd_send_signal_syscall_support(); test_pidfd_send_signal_simple_success(); test_pidfd_send_signal_exited_fail(); |