1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3
4 Copyright (c) 2020 Cyril Hrubis <chrubis@suse.cz>
5
6 */
7 /*
8
9 Basic test for timens_offsets error handling.
10
11 After a call to unshare(CLONE_NEWTIME) a new timer namespace is created, the
12 process that has called the unshare() can adjust offsets for CLOCK_MONOTONIC
13 and CLOCK_BOOTTIME for its children by writing to the '/proc/self/timens_offsets'.
14
15 */
16
17 #define _GNU_SOURCE
18 #include "lapi/namespaces_constants.h"
19 #include "lapi/posix_clocks.h"
20 #include "tst_test.h"
21
22 static struct tcase {
23 const char *desc;
24 const char *offsets;
25 int exp_err;
26 } tcases[] = {
27 {"Obvious garbage", "not an offset", EINVAL},
28 {"Missing nanoseconds", "1 10", EINVAL},
29 {"Negative nanoseconds", "1 10 -10", EINVAL},
30 {"Nanoseconds > 1s", "1 10 1000000001", EINVAL},
31 {"Unsupported CLOCK_REALTIME", "0 10 0", EINVAL},
32 {"Mess on the second line", "1 10 0\na", EINVAL},
33 {"Overflow kernel 64bit ns timer", "1 9223372036 0", ERANGE},
34 {"Overflow kernel 64bit ns timer", "1 -9223372036 0", ERANGE},
35 };
36
verify_ns_clock(unsigned int n)37 static void verify_ns_clock(unsigned int n)
38 {
39 struct tcase *tc = &tcases[n];
40 int fd, ret;
41
42 SAFE_UNSHARE(CLONE_NEWTIME);
43
44 fd = SAFE_OPEN("/proc/self/timens_offsets", O_WRONLY);
45 ret = write(fd, tc->offsets, strlen(tc->offsets));
46
47 if (ret != -1) {
48 tst_res(TFAIL, "%s returned %i", tc->desc, ret);
49 return;
50 }
51
52 if (errno != tc->exp_err) {
53 tst_res(TFAIL | TERRNO, "%s should fail with %s, got:",
54 tc->desc, tst_strerrno(tc->exp_err));
55 return;
56 }
57
58 tst_res(TPASS | TERRNO, "%s", tc->desc);
59 }
60
61 static struct tst_test test = {
62 .tcnt = ARRAY_SIZE(tcases),
63 .test = verify_ns_clock,
64 .needs_root = 1,
65 .needs_kconfigs = (const char *[]) {
66 "CONFIG_TIME_NS=y",
67 NULL
68 }
69 };
70