[PATCHv8 34/34] selftests/timens: Check for right timens offsets after fork and exec

Dmitry Safonov
2019-11-12T01:27:23Z

From: Andrei Vagin <avagin@gmail.com>

Output on success:
1..1
ok 1 exec
# Pass 1 Fail 0 Xfail 0 Xpass 0 Skip 0 Error 0

Output on failure:
1..1
not ok 1 36016 16
Bail out!

Output with lack of permissions:
1..1
not ok 1 # SKIP need to run as root

Output without support of time namespaces:
1..1
not ok 1 # SKIP Time namespaces are not supported

Signed-off-by: Andrei Vagin <avagin@gmail.com>
Co-developed-by: Dmitry Safonov <dima@arista.com>
Signed-off-by: Dmitry Safonov <dima@arista.com>
---
tools/testing/selftests/timens/.gitignore | 1 +
tools/testing/selftests/timens/Makefile | 2 +-
tools/testing/selftests/timens/exec.c | 94 +++++++++++++++++++++++
3 files changed, 96 insertions(+), 1 deletion(-)
create mode 100644 tools/testing/selftests/timens/exec.c

diff --git a/tools/testing/selftests/timens/.gitignore b/tools/testing/selftests/timens/.gitignore
index 16292e4d08a5..789f21e81028 100644
--- a/tools/testing/selftests/timens/.gitignore
+++ b/tools/testing/selftests/timens/.gitignore
@@ -1,4 +1,5 @@
clock_nanosleep
+exec
gettime_perf
gettime_perf_cold
procfs
diff --git a/tools/testing/selftests/timens/Makefile b/tools/testing/selftests/timens/Makefile
index 6aefcaccb8f4..e9fb30bd8aeb 100644
--- a/tools/testing/selftests/timens/Makefile
+++ b/tools/testing/selftests/timens/Makefile
@@ -1,4 +1,4 @@
-TEST_GEN_PROGS := timens timerfd timer clock_nanosleep procfs
+TEST_GEN_PROGS := timens timerfd timer clock_nanosleep procfs exec
TEST_GEN_PROGS_EXTENDED := gettime_perf

CFLAGS := -Wall -Werror -pthread
diff --git a/tools/testing/selftests/timens/exec.c b/tools/testing/selftests/timens/exec.c
new file mode 100644
index 000000000000..87b47b557a7a
--- /dev/null
+++ b/tools/testing/selftests/timens/exec.c
@@ -0,0 +1,94 @@
+// SPDX-License-Identifier: GPL-2.0
+#define _GNU_SOURCE
+#include <errno.h>
+#include <fcntl.h>
+#include <sched.h>
+#include <stdio.h>
+#include <stdbool.h>
+#include <sys/stat.h>
+#include <sys/syscall.h>
+#include <sys/types.h>
+#include <sys/wait.h>
+#include <time.h>
+#include <unistd.h>
+#include <time.h>
+#include <string.h>
+
+#include "log.h"
+#include "timens.h"
+
+#define OFFSET (36000)
+
+int main(int argc, char *argv[])
+{
+ struct timespec now, tst;
+ int status, i;
+ pid_t pid;
+
+ if (argc > 1) {
+ if (sscanf(argv[1], "%ld", &now.tv_sec) != 1)
+ return pr_perror("sscanf");
+
+ for (i = 0; i < 2; i++) {
+ _gettime(CLOCK_MONOTONIC, &tst, i);
+ if (abs(tst.tv_sec - now.tv_sec) > 5)
+ return pr_fail("%ld %ld\n", now.tv_sec, tst.tv_sec);
+ }
+ return 0;
+ }
+
+ nscheck();
+
+ ksft_set_plan(1);
+
+ clock_gettime(CLOCK_MONOTONIC, &now);
+
+ if (unshare_timens())
+ return 1;
+
+ if (_settime(CLOCK_MONOTONIC, OFFSET))
+ return 1;
+
+ for (i = 0; i < 2; i++) {
+ _gettime(CLOCK_MONOTONIC, &tst, i);
+ if (abs(tst.tv_sec - now.tv_sec) > 5)
+ return pr_fail("%ld %ld\n",
+ now.tv_sec, tst.tv_sec);
+ }
+
+ if (argc > 1)
+ return 0;
+
+ pid = fork();
+ if (pid < 0)
+ return pr_perror("fork");
+
+ if (pid == 0) {
+ char now_str[64];
+ char *cargv[] = {"exec", now_str, NULL};
+ char *cenv[] = {NULL};
+
+ /* Check that a child process is in the new timens. */
+ for (i = 0; i < 2; i++) {
+ _gettime(CLOCK_MONOTONIC, &tst, i);
+ if (abs(tst.tv_sec - now.tv_sec - OFFSET) > 5)
+ return pr_fail("%ld %ld\n",
+ now.tv_sec + OFFSET, tst.tv_sec);
+ }
+
+ /* Check for proper vvar offsets after execve. */
+ snprintf(now_str, sizeof(now_str), "%ld", now.tv_sec + OFFSET);
+ execve("/proc/self/exe", cargv, cenv);
+ return pr_perror("execve");
+ }
+
+ if (waitpid(pid, &status, 0) != pid)
+ return pr_perror("waitpid");
+
+ if (status)
+ ksft_exit_fail();
+
+ ksft_test_result_pass("exec\n");
+ ksft_exit_pass();
+ return 0;
+}
--
2.24.0