1 /*
2 * Copyright (c) Huawei Technologies Co., Ltd., 2015
3 * This program is free software; you can redistribute it and/or modify
4 * it under the terms of the GNU General Public License as published by
5 * the Free Software Foundation; either version 2 of the License, or
6 * (at your option) any later version.
7 *
8 * This program is distributed in the hope that it will be useful,
9 * but WITHOUT ANY WARRANTY; without even the implied warranty of
10 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See
11 * the GNU General Public License for more details.
12 */
13
14 /*
15 * Verify that:
16 * The kernel imposes a limit of at least 32 nested levels on user namespaces.
17 */
18
19 #define _GNU_SOURCE
20 #include <sys/wait.h>
21 #include <assert.h>
22 #include <stdio.h>
23 #include <stdlib.h>
24 #include <unistd.h>
25 #include <string.h>
26 #include <errno.h>
27 #include "userns_helper.h"
28 #include "test.h"
29
30 #define MAXNEST 32
31
32 char *TCID = "userns07";
33 int TST_TOTAL = 1;
34
setup(void)35 static void setup(void)
36 {
37 check_newuser();
38 tst_tmpdir();
39 TST_CHECKPOINT_INIT(NULL);
40 }
41
cleanup(void)42 static void cleanup(void)
43 {
44 tst_rmdir();
45 }
46
child_fn1(void * arg)47 static int child_fn1(void *arg)
48 {
49 pid_t cpid1;
50 long level = (long)arg;
51 int status;
52 int parentuid;
53 int parentgid;
54
55 TST_SAFE_CHECKPOINT_WAIT(NULL, 0);
56
57 if (level == MAXNEST)
58 return 0;
59 cpid1 = ltp_clone_quick(CLONE_NEWUSER | SIGCHLD,
60 (void *)child_fn1, (void *)(level + 1));
61 if (cpid1 < 0) {
62 printf("level %ld:unexpected error: (%d) %s\n",
63 level, errno, strerror(errno));
64 return 1;
65 }
66
67 parentuid = geteuid();
68 parentgid = getegid();
69
70 updatemap(cpid1, UID_MAP, 0, parentuid, NULL);
71 updatemap(cpid1, GID_MAP, 0, parentgid, NULL);
72
73 TST_SAFE_CHECKPOINT_WAKE(cleanup, 0);
74
75 if (waitpid(cpid1, &status, 0) == -1)
76 return 1;
77
78 if (WIFEXITED(status) && WEXITSTATUS(status) != 0) {
79 printf("child exited abnormally\n");
80 return 1;
81 } else if (WIFSIGNALED(status)) {
82 printf("child was killed with signal = %d", WTERMSIG(status));
83 return 1;
84 }
85 return 0;
86 }
87
test_max_nest(void)88 static void test_max_nest(void)
89 {
90 pid_t cpid1;
91 int parentuid;
92 int parentgid;
93 int fd;
94 char path[BUFSIZ];
95
96 cpid1 = ltp_clone_quick(CLONE_NEWUSER | SIGCHLD,
97 (void *)child_fn1, (void *)0);
98 if (cpid1 < 0)
99 tst_brkm(TBROK | TERRNO, cleanup, "clone failed");
100
101 parentuid = geteuid();
102 parentgid = getegid();
103
104 if (access("/proc/self/setgroups", F_OK) == 0) {
105 sprintf(path, "/proc/%d/setgroups", cpid1);
106 fd = SAFE_OPEN(cleanup, path, O_WRONLY, 0644);
107 SAFE_WRITE(cleanup, 1, fd, "deny", 4);
108 SAFE_CLOSE(cleanup, fd);
109 }
110
111 updatemap(cpid1, UID_MAP, 0, parentuid, cleanup);
112 updatemap(cpid1, GID_MAP, 0, parentgid, cleanup);
113
114 TST_SAFE_CHECKPOINT_WAKE(cleanup, 0);
115 tst_record_childstatus(cleanup, cpid1);
116 }
117
main(int argc,char * argv[])118 int main(int argc, char *argv[])
119 {
120 int lc;
121
122 setup();
123 tst_parse_opts(argc, argv, NULL, NULL);
124
125 for (lc = 0; TEST_LOOPING(lc); lc++) {
126 tst_count = 0;
127 test_max_nest();
128 }
129
130 cleanup();
131 tst_exit();
132 }
133
134