Unverified Commit 716e343f authored by Michael Weiß's avatar Michael Weiß Committed by Christian Brauner
Browse files

selftests/timens: added selftest for /proc/stat btime 



Test that btime value of /proc/stat is as expected in the time namespace
using a simple parser to get btime from /proc/stat.

Signed-off-by: default avatarMichael Weiß <michael.weiss@aisec.fraunhofer.de>
Reviewed-by: default avatarAndrei Vagin <avagin@gmail.com>
Acked-by: default avatarThomas Gleixner <tglx@linutronix.de>
Acked-by: default avatarChristian Brauner <christian.brauner@ubuntu.com>
Link: https://lore.kernel.org/r/20201027204258.7869-4-michael.weiss@aisec.fraunhofer.de
parent 3ae700ec

tools/testing/selftests/timens/procfs.c

+57 −1
Original line number Diff line number Diff line
@@ -93,6 +93,33 @@ static int read_proc_uptime(struct timespec *uptime) 
	return 0;

}



static int read_proc_stat_btime(unsigned long long *boottime_sec)

{

	FILE *proc;

	char line_buf[2048];



	proc = fopen("/proc/stat", "r");

	if (proc == NULL) {

		pr_perror("Unable to open /proc/stat");

		return -1;

	}



	while (fgets(line_buf, 2048, proc)) {

		if (sscanf(line_buf, "btime %llu", boottime_sec) != 1)

			continue;

		fclose(proc);

		return 0;

	}

	if (errno) {

		pr_perror("fscanf");

		fclose(proc);

		return -errno;

	}

	pr_err("failed to parse /proc/stat");

	fclose(proc);

	return -1;

}



static int check_uptime(void)

{

	struct timespec uptime_new, uptime_old;
@@ -123,18 +150,47 @@ static int check_uptime(void) 
	return 0;

}



static int check_stat_btime(void)

{

	unsigned long long btime_new, btime_old;

	unsigned long long btime_expected;



	if (switch_ns(parent_ns))

		return pr_err("switch_ns(%d)", parent_ns);



	if (read_proc_stat_btime(&btime_old))

		return 1;



	if (switch_ns(child_ns))

		return pr_err("switch_ns(%d)", child_ns);



	if (read_proc_stat_btime(&btime_new))

		return 1;



	btime_expected = btime_old - TEN_DAYS_IN_SEC;

	if (btime_new != btime_expected) {

		pr_fail("btime in /proc/stat: old %llu, new %llu [%llu]",

			btime_old, btime_new, btime_expected);

		return 1;

	}



	ksft_test_result_pass("Passed for /proc/stat btime\n");

	return 0;

}



int main(int argc, char *argv[])

{

	int ret = 0;



	nscheck();



	ksft_set_plan(1);

	ksft_set_plan(2);



	if (init_namespaces())

		return 1;



	ret |= check_uptime();

	ret |= check_stat_btime();



	if (ret)

		ksft_exit_fail();