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Note: File does not exist in v4.10.11.
  1// SPDX-License-Identifier: GPL-2.0
  2#define _GNU_SOURCE
  3#include <errno.h>
  4#include <fcntl.h>
  5#include <sched.h>
  6#include <stdio.h>
  7#include <stdbool.h>
  8#include <sys/stat.h>
  9#include <sys/syscall.h>
 10#include <sys/types.h>
 11#include <sys/wait.h>
 12#include <time.h>
 13#include <unistd.h>
 14#include <string.h>
 15#include <pthread.h>
 16
 17#include "log.h"
 18#include "timens.h"
 19
 20#define OFFSET (36000)
 21
 22struct thread_args {
 23	char *tst_name;
 24	struct timespec *now;
 25};
 26
 27static void *tcheck(void *_args)
 28{
 29	struct thread_args *args = _args;
 30	struct timespec *now = args->now, tst;
 31	int i;
 32
 33	for (i = 0; i < 2; i++) {
 34		_gettime(CLOCK_MONOTONIC, &tst, i);
 35		if (abs(tst.tv_sec - now->tv_sec) > 5) {
 36			pr_fail("%s: in-thread: unexpected value: %ld (%ld)\n",
 37				args->tst_name, tst.tv_sec, now->tv_sec);
 38			return (void *)1UL;
 39		}
 40	}
 41	return NULL;
 42}
 43
 44static int check_in_thread(char *tst_name, struct timespec *now)
 45{
 46	struct thread_args args = {
 47		.tst_name = tst_name,
 48		.now = now,
 49	};
 50	pthread_t th;
 51	void *retval;
 52
 53	if (pthread_create(&th, NULL, tcheck, &args))
 54		return pr_perror("thread");
 55	if (pthread_join(th, &retval))
 56		return pr_perror("pthread_join");
 57	return !(retval == NULL);
 58}
 59
 60static int check(char *tst_name, struct timespec *now)
 61{
 62	struct timespec tst;
 63	int i;
 64
 65	for (i = 0; i < 2; i++) {
 66		_gettime(CLOCK_MONOTONIC, &tst, i);
 67		if (abs(tst.tv_sec - now->tv_sec) > 5)
 68			return pr_fail("%s: unexpected value: %ld (%ld)\n",
 69					tst_name, tst.tv_sec, now->tv_sec);
 70	}
 71	if (check_in_thread(tst_name, now))
 72		return 1;
 73	ksft_test_result_pass("%s\n", tst_name);
 74	return 0;
 75}
 76
 77int main(int argc, char *argv[])
 78{
 79	struct timespec now;
 80	int status;
 81	pid_t pid;
 82
 83	if (argc > 1) {
 84		char *endptr;
 85
 86		ksft_cnt.ksft_pass = 1;
 87		now.tv_sec = strtoul(argv[1], &endptr, 0);
 88		if (*endptr != 0)
 89			return pr_perror("strtoul");
 90
 91		return check("child after exec", &now);
 92	}
 93
 94	nscheck();
 95
 96	ksft_set_plan(4);
 97
 98	clock_gettime(CLOCK_MONOTONIC, &now);
 99
100	if (unshare_timens())
101		return 1;
102
103	if (_settime(CLOCK_MONOTONIC, OFFSET))
104		return 1;
105
106	if (check("parent before vfork", &now))
107		return 1;
108
109	pid = vfork();
110	if (pid < 0)
111		return pr_perror("fork");
112
113	if (pid == 0) {
114		char now_str[64];
115		char *cargv[] = {"exec", now_str, NULL};
116		char *cenv[] = {NULL};
117
118		/* Check for proper vvar offsets after execve. */
119		snprintf(now_str, sizeof(now_str), "%ld", now.tv_sec + OFFSET);
120		execve("/proc/self/exe", cargv, cenv);
121		pr_perror("execve");
122		_exit(1);
123	}
124
125	if (waitpid(pid, &status, 0) != pid)
126		return pr_perror("waitpid");
127
128	if (status)
129		ksft_exit_fail();
130	ksft_inc_pass_cnt();
131	ksft_test_result_pass("wait for child\n");
132
133	/* Check that we are still in the source timens. */
134	if (check("parent after vfork", &now))
135		return 1;
136
137	ksft_exit_pass();
138	return 0;
139}