Check that /proc/uptime is correct inside a new time namespace. Co-developed-by: Andrei Vagin <avagin@xxxxxxxxx> Signed-off-by: Andrei Vagin <avagin@xxxxxxxxx> Signed-off-by: Dmitry Safonov <dima@xxxxxxxxxx> --- tools/testing/selftests/timens/.gitignore | 1 + tools/testing/selftests/timens/Makefile | 2 +- tools/testing/selftests/timens/procfs.c | 142 ++++++++++++++++++++++ 3 files changed, 144 insertions(+), 1 deletion(-) create mode 100644 tools/testing/selftests/timens/procfs.c diff --git a/tools/testing/selftests/timens/.gitignore b/tools/testing/selftests/timens/.gitignore index 9b6c8ddac2c8..94ffdd9cead7 100644 --- a/tools/testing/selftests/timens/.gitignore +++ b/tools/testing/selftests/timens/.gitignore @@ -1,3 +1,4 @@ clock_nanosleep +procfs timens timerfd diff --git a/tools/testing/selftests/timens/Makefile b/tools/testing/selftests/timens/Makefile index 76a1dc891184..f96f50d1fef8 100644 --- a/tools/testing/selftests/timens/Makefile +++ b/tools/testing/selftests/timens/Makefile @@ -1,4 +1,4 @@ -TEST_GEN_PROGS := timens timerfd clock_nanosleep +TEST_GEN_PROGS := timens timerfd clock_nanosleep procfs CFLAGS := -Wall -Werror diff --git a/tools/testing/selftests/timens/procfs.c b/tools/testing/selftests/timens/procfs.c new file mode 100644 index 000000000000..af839688ecc6 --- /dev/null +++ b/tools/testing/selftests/timens/procfs.c @@ -0,0 +1,142 @@ +// SPDX-License-Identifier: GPL-2.0 +#define _GNU_SOURCE +#include <errno.h> +#include <fcntl.h> +#include <math.h> +#include <sched.h> +#include <stdio.h> +#include <stdbool.h> +#include <stdlib.h> +#include <sys/stat.h> +#include <sys/syscall.h> +#include <sys/types.h> +#include <time.h> +#include <unistd.h> +#include <time.h> + +#include "log.h" +#include "timens.h" + +/* + * Test shouldn't be run for a day, so add 10 days to child + * time and check parent's time to be in the same day. + */ +#define MAX_TEST_TIME_SEC (60*5) +#define DAY_IN_SEC (60*60*24) +#define TEN_DAYS_IN_SEC (10*DAY_IN_SEC) + +#define ARRAY_SIZE(arr) (sizeof(arr) / sizeof((arr)[0])) + +static int child_ns, parent_ns; + +static int switch_ns(int fd) +{ + if (setns(fd, CLONE_NEWTIME)) + return pr_perror("setns()"); + + return 0; +} + +static int init_namespaces(void) +{ + char path[] = "/proc/self/ns/time_for_children"; + struct stat st1, st2; + + parent_ns = open(path, O_RDONLY); + if (parent_ns <= 0) + return pr_perror("Unable to open %s", path); + + if (fstat(parent_ns, &st1)) + return pr_perror("Unable to stat the parent timens"); + + if (unshare(CLONE_NEWTIME)) + return pr_perror("Can't unshare() timens"); + + child_ns = open(path, O_RDONLY); + if (child_ns <= 0) + return pr_perror("Unable to open %s", path); + + if (fstat(child_ns, &st2)) + return pr_perror("Unable to stat the timens"); + + if (st1.st_ino == st2.st_ino) + return pr_err("The same child_ns after CLONE_NEWTIME"); + + if (_settime(CLOCK_BOOTTIME, TEN_DAYS_IN_SEC)) + return -1; + + return 0; +} + +static int read_proc_uptime(struct timespec *uptime) +{ + unsigned long up_sec, up_nsec; + FILE *proc; + + proc = fopen("/proc/uptime", "r"); + if (proc == NULL) { + pr_perror("Unable to open /proc/uptime"); + return -1; + } + + if (fscanf(proc, "%lu.%02lu", &up_sec, &up_nsec) != 2) { + if (errno) { + pr_perror("fscanf"); + return -errno; + } + pr_err("failed to parse /proc/uptime"); + return -1; + } + fclose(proc); + + uptime->tv_sec = up_sec; + uptime->tv_nsec = up_nsec; + return 0; +} + +static int check_uptime(void) +{ + struct timespec uptime_new, uptime_old; + time_t uptime_expected; + double prec = MAX_TEST_TIME_SEC; + + if (switch_ns(parent_ns)) + return pr_err("switch_ns(%d)", parent_ns); + + if (read_proc_uptime(&uptime_old)) + return 1; + + if (switch_ns(child_ns)) + return pr_err("switch_ns(%d)", child_ns); + + if (read_proc_uptime(&uptime_new)) + return 1; + + uptime_expected = uptime_old.tv_sec + TEN_DAYS_IN_SEC; + if (fabs(difftime(uptime_new.tv_sec, uptime_expected)) > prec) { + pr_fail("uptime in /proc/uptime: old %ld, new %ld [%ld]", + uptime_old.tv_sec, uptime_new.tv_sec, + uptime_old.tv_sec + TEN_DAYS_IN_SEC); + return 1; + } + + ksft_test_result_pass("Passed for /proc/uptime"); + return 0; +} + +int main(int argc, char *argv[]) +{ + int ret = 0; + + nscheck(); + + if (init_namespaces()) + return 1; + + ret |= check_uptime(); + + if (ret) + ksft_exit_fail(); + ksft_exit_pass(); + return ret; +} -- 2.20.1