1 | /* Copyright (C) 2014-2024 Free Software Foundation, Inc. |
2 | This file is part of the GNU C Library. |
3 | |
4 | The GNU C Library is free software; you can redistribute it and/or |
5 | modify it under the terms of the GNU Lesser General Public |
6 | License as published by the Free Software Foundation; either |
7 | version 2.1 of the License, or (at your option) any later version. |
8 | |
9 | The GNU C Library is distributed in the hope that it will be useful, |
10 | but WITHOUT ANY WARRANTY; without even the implied warranty of |
11 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
12 | Lesser General Public License for more details. |
13 | |
14 | You should have received a copy of the GNU Lesser General Public |
15 | License along with the GNU C Library; if not, see |
16 | <https://www.gnu.org/licenses/>. */ |
17 | |
18 | #include <errno.h> |
19 | #include <pthread.h> |
20 | #include <signal.h> |
21 | #include <stdbool.h> |
22 | #include <stdio.h> |
23 | #include <support/xthread.h> |
24 | #include <sys/syscall.h> |
25 | #include <unistd.h> |
26 | |
27 | /* Check that a partial setuid failure aborts the process. */ |
28 | |
29 | static pthread_mutex_t mutex = PTHREAD_MUTEX_INITIALIZER; |
30 | static pthread_cond_t cond_send; |
31 | static void (*func_sent) (void); |
32 | static pthread_cond_t cond_recv; |
33 | |
34 | #define FAIL(fmt, ...) \ |
35 | do { printf ("FAIL: " fmt "\n", __VA_ARGS__); _exit (1); } while (0) |
36 | |
37 | static void * |
38 | thread_func (void *ctx __attribute__ ((unused))) |
39 | { |
40 | xpthread_mutex_lock (mutex: &mutex); |
41 | while (true) |
42 | { |
43 | if (func_sent != NULL) |
44 | { |
45 | void (*func) (void) = func_sent; |
46 | xpthread_mutex_unlock (mutex: &mutex); |
47 | |
48 | func (); |
49 | |
50 | xpthread_mutex_lock (mutex: &mutex); |
51 | func_sent = NULL; |
52 | xpthread_cond_signal (cond: &cond_recv); |
53 | } |
54 | xpthread_cond_wait (cond: &cond_send, mutex: &mutex); |
55 | } |
56 | return NULL; |
57 | } |
58 | |
59 | static void |
60 | run_on_thread (void (*func) (void)) |
61 | { |
62 | xpthread_mutex_lock (mutex: &mutex); |
63 | func_sent = func; |
64 | xpthread_mutex_unlock (mutex: &mutex); |
65 | |
66 | xpthread_cond_signal (cond: &cond_send); |
67 | |
68 | xpthread_mutex_lock (mutex: &mutex); |
69 | while (func_sent != NULL) |
70 | { |
71 | xpthread_cond_wait (cond: &cond_recv, mutex: &mutex); |
72 | } |
73 | xpthread_mutex_unlock (mutex: &mutex); |
74 | } |
75 | |
76 | static void |
77 | change_thread_ids (void) |
78 | { |
79 | long ret = syscall (__NR_setresuid, 2001, 2002, 2003); |
80 | if (ret != 0) |
81 | FAIL ("setresuid (2001, 2002, 2003): %ld" , ret); |
82 | } |
83 | |
84 | static uid_t ruid, euid, suid; |
85 | |
86 | static void |
87 | get_thread_ids (void) |
88 | { |
89 | if (getresuid (ruid: &ruid, euid: &euid, suid: &suid) < 0) |
90 | FAIL ("getresuid: %m (%d)" , errno); |
91 | } |
92 | |
93 | static void |
94 | abort_expected (int signal __attribute__ ((unused))) |
95 | { |
96 | _exit (0); |
97 | } |
98 | |
99 | static int |
100 | do_test (void) |
101 | { |
102 | pthread_t thread; |
103 | int ret = pthread_create (newthread: &thread, NULL, start_routine: thread_func, NULL); |
104 | if (ret != 0) |
105 | FAIL ("pthread_create: %d" , ret); |
106 | |
107 | run_on_thread (func: change_thread_ids); |
108 | |
109 | signal (SIGABRT, handler: &abort_expected); |
110 | /* This should abort the process. */ |
111 | if (setresuid (ruid: 1001, euid: 1002, suid: 1003) < 0) |
112 | FAIL ("setresuid: %m (%d)" , errno); |
113 | signal (SIGABRT, SIG_DFL); |
114 | |
115 | /* If we get here, check that the kernel did the right thing. */ |
116 | run_on_thread (func: get_thread_ids); |
117 | if (ruid != 1001 || euid != 1002 || suid != 1003) |
118 | FAIL ("unexpected UIDs after setuid: %ld, %ld, %ld" , |
119 | (long) ruid, (long) euid, (long) suid); |
120 | return 0; |
121 | } |
122 | |
123 | #include <support/test-driver.c> |
124 | |