1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
|
// SPDX-License-Identifier: GPL-2.0-or-later
/*
* Copyright (c) Huawei Technologies Co., Ltd., 2015
* Copyright (C) 2022 SUSE LLC Andrea Cervesato <andrea.cervesato@suse.com>
*/
/*\
* [Description]
*
* Verify that if a process created via fork(2) or clone(2) without the
* CLONE_NEWUSER flag is a member of the same user namespace as its parent.
*
* When unshare an user namespace, the calling process is moved into a new user
* namespace which is not shared with any previously existing process.
*/
#define _GNU_SOURCE
#include <stdio.h>
#include "tst_test.h"
#include "lapi/sched.h"
#include "common.h"
static void child_fn1(void)
{
TST_CHECKPOINT_WAIT(0);
}
static unsigned int getusernsidbypid(int pid)
{
char path[BUFSIZ];
char userid[BUFSIZ];
unsigned int id = 0;
sprintf(path, "/proc/%d/ns/user", pid);
SAFE_READLINK(path, userid, BUFSIZ);
if (sscanf(userid, "user:[%u]", &id) < 0)
tst_brk(TBROK | TERRNO, "sscanf failure");
return id;
}
static void run(void)
{
const struct tst_clone_args args1 = { .exit_signal = SIGCHLD };
const struct tst_clone_args args2 = {
.flags = CLONE_NEWUSER,
.exit_signal = SIGCHLD,
};
int cpid1, cpid2, cpid3;
unsigned int parentuserns, cpid1userns, cpid2userns, newparentuserns;
parentuserns = getusernsidbypid(getpid());
cpid1 = SAFE_CLONE(&args1);
if (!cpid1) {
child_fn1();
return;
}
cpid1userns = getusernsidbypid(cpid1);
TST_CHECKPOINT_WAKE(0);
/* A process created via fork(2) or clone(2) without the
* CLONE_NEWUSER flag is a member of the same user namespace as its
* parent
*/
TST_EXP_EQ_LI(parentuserns, cpid1userns);
cpid2 = SAFE_CLONE(&args2);
if (!cpid2) {
child_fn1();
return;
}
cpid2userns = getusernsidbypid(cpid2);
TST_CHECKPOINT_WAKE(0);
TST_EXP_EXPR(parentuserns != cpid2userns,
"parent namespace != child namespace");
cpid3 = SAFE_FORK();
if (!cpid3) {
SAFE_UNSHARE(CLONE_NEWUSER);
newparentuserns = getusernsidbypid(getpid());
/* When unshare an user namespace, the calling process
* is moved into a new user namespace which is not shared
* with any previously existing process
*/
TST_EXP_EXPR(parentuserns != newparentuserns,
"parent namespace != unshared child namespace");
}
}
static struct tst_test test = {
.test_all = run,
.needs_root = 1,
.forks_child = 1,
.needs_checkpoints = 1,
.needs_kconfigs = (const char *[]) {
"CONFIG_USER_NS",
NULL,
},
};
|
