xref: /aosp_15_r20/external/ltp/testcases/kernel/syscalls/fchmod/fchmod03.c (revision 49cdfc7efb34551c7342be41a7384b9c40d7cab7)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  *   Copyright (c) International Business Machines  Corp., 2001
4  */
5 
6 /*\
7  * [Description]
8  *
9  * Verify that, fchmod(2) will succeed to change the mode of a file
10  * and set the sticky bit on it if invoked by non-root (uid != 0)
11  * process with the following constraints:
12  *
13  * - the process is the owner of the file
14  * - the effective group ID or one of the supplementary group ID's of the
15  *   process is equal to the group ID of the file
16  */
17 
18 #include <pwd.h>
19 #include "fchmod.h"
20 #include "tst_test.h"
21 
22 static int fd;
23 static const char nobody_uid[] = "nobody";
24 static struct passwd *ltpuser;
25 
verify_fchmod(void)26 static void verify_fchmod(void)
27 {
28 	struct stat stat_buf;
29 	mode_t file_mode;
30 
31 	TST_EXP_PASS_SILENT(fchmod(fd, PERMS));
32 
33 	if (fstat(fd, &stat_buf) == -1)
34 		tst_brk(TFAIL | TERRNO, "fstat failed");
35 	file_mode = stat_buf.st_mode;
36 
37 	if ((file_mode & PERMS) != PERMS)
38 		tst_res(TFAIL, "%s: Incorrect modes 0%3o, "
39 			"Expected 0777", TESTFILE, file_mode);
40 	else
41 		tst_res(TPASS, "Functionality of fchmod(%d, "
42 			"%#o) successful", fd, PERMS);
43 }
44 
setup(void)45 static void setup(void)
46 {
47 	ltpuser = SAFE_GETPWNAM(nobody_uid);
48 
49 	SAFE_SETEUID(ltpuser->pw_uid);
50 
51 	fd = SAFE_OPEN(TESTFILE, O_RDWR | O_CREAT, FILE_MODE);
52 }
53 
cleanup(void)54 static void cleanup(void)
55 {
56 	if (fd > 0)
57 		SAFE_CLOSE(fd);
58 }
59 
60 static struct tst_test test = {
61 	.test_all = verify_fchmod,
62 	.setup = setup,
63 	.cleanup = cleanup,
64 	.needs_tmpdir = 1,
65 	.needs_root = 1,
66 };
67