1// SPDX-License-Identifier: GPL-2.0
  2#define _GNU_SOURCE
  3#include <errno.h>
  4#include <fcntl.h>
  5#include <math.h>
  6#include <sched.h>
  7#include <stdio.h>
  8#include <stdbool.h>
  9#include <stdlib.h>
 10#include <sys/stat.h>
 11#include <sys/syscall.h>
 12#include <sys/types.h>
 13#include <time.h>
 14#include <unistd.h>
 15
 16#include "log.h"
 17#include "timens.h"
 18
 19/*
 20 * Test shouldn't be run for a day, so add 10 days to child
 21 * time and check parent's time to be in the same day.
 22 */
 23#define MAX_TEST_TIME_SEC		(60*5)
 24#define DAY_IN_SEC			(60*60*24)
 25#define TEN_DAYS_IN_SEC			(10*DAY_IN_SEC)
 26
 27#define ARRAY_SIZE(arr) (sizeof(arr) / sizeof((arr)[0]))
 28
 29static int child_ns, parent_ns;
 30
 31static int switch_ns(int fd)
 32{
 33	if (setns(fd, CLONE_NEWTIME))
 34		return pr_perror("setns()");
 35
 36	return 0;
 37}
 38
 39static int init_namespaces(void)
 40{
 41	char path[] = "/proc/self/ns/time_for_children";
 42	struct stat st1, st2;
 43
 44	parent_ns = open(path, O_RDONLY);
 45	if (parent_ns <= 0)
 46		return pr_perror("Unable to open %s", path);
 47
 48	if (fstat(parent_ns, &st1))
 49		return pr_perror("Unable to stat the parent timens");
 50
 51	if (unshare_timens())
 52		return -1;
 53
 54	child_ns = open(path, O_RDONLY);
 55	if (child_ns <= 0)
 56		return pr_perror("Unable to open %s", path);
 57
 58	if (fstat(child_ns, &st2))
 59		return pr_perror("Unable to stat the timens");
 60
 61	if (st1.st_ino == st2.st_ino)
 62		return pr_err("The same child_ns after CLONE_NEWTIME");
 63
 64	if (_settime(CLOCK_BOOTTIME, TEN_DAYS_IN_SEC))
 65		return -1;
 66
 67	return 0;
 68}
 69
 70static int read_proc_uptime(struct timespec *uptime)
 71{
 72	unsigned long up_sec, up_nsec;
 73	FILE *proc;
 74
 75	proc = fopen("/proc/uptime", "r");
 76	if (proc == NULL) {
 77		pr_perror("Unable to open /proc/uptime");
 78		return -1;
 79	}
 80
 81	if (fscanf(proc, "%lu.%02lu", &up_sec, &up_nsec) != 2) {
 82		if (errno) {
 83			pr_perror("fscanf");
 84			return -errno;
 85		}
 86		pr_err("failed to parse /proc/uptime");
 87		return -1;
 88	}
 89	fclose(proc);
 90
 91	uptime->tv_sec = up_sec;
 92	uptime->tv_nsec = up_nsec;
 93	return 0;
 94}
 95
 96static int read_proc_stat_btime(unsigned long long *boottime_sec)
 97{
 98	FILE *proc;
 99	char line_buf[2048];
100
101	proc = fopen("/proc/stat", "r");
102	if (proc == NULL) {
103		pr_perror("Unable to open /proc/stat");
104		return -1;
105	}
106
107	while (fgets(line_buf, 2048, proc)) {
108		if (sscanf(line_buf, "btime %llu", boottime_sec) != 1)
109			continue;
110		fclose(proc);
111		return 0;
112	}
113	if (errno) {
114		pr_perror("fscanf");
115		fclose(proc);
116		return -errno;
117	}
118	pr_err("failed to parse /proc/stat");
119	fclose(proc);
120	return -1;
121}
122
123static int check_uptime(void)
124{
125	struct timespec uptime_new, uptime_old;
126	time_t uptime_expected;
127	double prec = MAX_TEST_TIME_SEC;
128
129	if (switch_ns(parent_ns))
130		return pr_err("switch_ns(%d)", parent_ns);
131
132	if (read_proc_uptime(&uptime_old))
133		return 1;
134
135	if (switch_ns(child_ns))
136		return pr_err("switch_ns(%d)", child_ns);
137
138	if (read_proc_uptime(&uptime_new))
139		return 1;
140
141	uptime_expected = uptime_old.tv_sec + TEN_DAYS_IN_SEC;
142	if (fabs(difftime(uptime_new.tv_sec, uptime_expected)) > prec) {
143		pr_fail("uptime in /proc/uptime: old %ld, new %ld [%ld]",
144			uptime_old.tv_sec, uptime_new.tv_sec,
145			uptime_old.tv_sec + TEN_DAYS_IN_SEC);
146		return 1;
147	}
148
149	ksft_test_result_pass("Passed for /proc/uptime\n");
150	return 0;
151}
152
153static int check_stat_btime(void)
154{
155	unsigned long long btime_new, btime_old;
156	unsigned long long btime_expected;
157
158	if (switch_ns(parent_ns))
159		return pr_err("switch_ns(%d)", parent_ns);
160
161	if (read_proc_stat_btime(&btime_old))
162		return 1;
163
164	if (switch_ns(child_ns))
165		return pr_err("switch_ns(%d)", child_ns);
166
167	if (read_proc_stat_btime(&btime_new))
168		return 1;
169
170	btime_expected = btime_old - TEN_DAYS_IN_SEC;
171	if (btime_new != btime_expected) {
172		pr_fail("btime in /proc/stat: old %llu, new %llu [%llu]",
173			btime_old, btime_new, btime_expected);
174		return 1;
175	}
176
177	ksft_test_result_pass("Passed for /proc/stat btime\n");
178	return 0;
179}
180
181int main(int argc, char *argv[])
182{
183	int ret = 0;
184
185	nscheck();
186
187	ksft_set_plan(2);
188
189	if (init_namespaces())
190		return 1;
191
192	ret |= check_uptime();
193	ret |= check_stat_btime();
194
195	if (ret)
196		ksft_exit_fail();
197	ksft_exit_pass();
198	return ret;
199}