1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  *   Copyright (c) 2013 Wanlong Gao <gaowanlong@cn.fujitsu.com>
4  *   Copyright (c) 2018 Linux Test Project
5  */
6 
7 /*
8  * DESCRIPTION
9  *	Check for the following errors:
10  *	1.	EEXIST
11  *	2.	EISDIR
12  *	3.	ENOTDIR
13  *	4.	ENAMETOOLONG
14  *	5.	EACCES
15  *	6.	EFAULT
16  *
17  * ALGORITHM
18  *	1. Open a file with O_CREAT and O_EXCL, when the file already
19  *	   exists. Check the errno for EEXIST
20  *
21  *	2. Pass a directory as the pathname and request a write access,
22  *	   check for errno for EISDIR
23  *
24  *	3. Specify O_DIRECTORY as a parameter to open and pass a file as the
25  *	   pathname, check errno for ENOTDIR
26  *
27  *	4. Attempt to open() a filename which is more than VFS_MAXNAMLEN, and
28  *	   check for errno to be ENAMETOOLONG.
29  *
30  *	5. Attempt to open a (0600) file owned by different user in WRONLY mode,
31  *	   open(2) should fail with EACCES.
32  *
33  *	6. Attempt to pass an invalid pathname with an address pointing outside
34  *	   the accessible address space of the process, as the argument to open(),
35  *	   and expect to get EFAULT.
36  */
37 
38 #define _GNU_SOURCE		/* for O_DIRECTORY */
39 #include <sys/types.h>
40 #include <sys/stat.h>
41 #include <stdio.h>
42 #include <errno.h>
43 #include <sys/mman.h>
44 #include <fcntl.h>
45 #include <signal.h>
46 #include <pwd.h>
47 #include "tst_test.h"
48 #include "tst_get_bad_addr.h"
49 
50 static char *existing_fname = "open08_testfile";
51 static char *toolong_fname = "abcdefghijklmnopqrstuvwxyzabcdefghijklmnopqrstuvwxyzabcdefghijklmnopqrstmnopqrstuvwxyzabcdefghijklmnopqrstmnopqrstuvwxyzabcdefghijklmnopqrstmnopqrstuvwxyzabcdefghijklmnopqrstmnopqrstuvwxyzabcdefghijklmnopqrstmnopqrstuvwxyzabcdefghijklmnopqrstmnopqrstuvwxyz";
52 static char *dir_fname = "/tmp";
53 static char *user2_fname = "user2_0600";
54 static char *unmapped_fname;
55 
56 struct test_case_t;
57 
58 static struct test_case_t {
59 	char **fname;
60 	int flags;
61 	int error;
62 } tcases[] = {
63 	{&existing_fname, O_CREAT | O_EXCL, EEXIST},
64 	{&dir_fname, O_RDWR, EISDIR},
65 	{&existing_fname, O_DIRECTORY, ENOTDIR},
66 	{&toolong_fname, O_RDWR, ENAMETOOLONG},
67 	{&user2_fname, O_WRONLY, EACCES},
68 	{&unmapped_fname, O_CREAT, EFAULT}
69 };
70 
verify_open(unsigned int i)71 void verify_open(unsigned int i)
72 {
73 	TEST(open(*tcases[i].fname, tcases[i].flags,
74 		S_IRUSR | S_IWUSR | S_IRGRP | S_IROTH));
75 
76 	if (TST_RET != -1) {
77 		tst_res(TFAIL, "call succeeded unexpectedly");
78 		return;
79 	}
80 
81 	if (TST_ERR == tcases[i].error) {
82 		tst_res(TPASS, "expected failure - "
83 				"errno = %d : %s", TST_ERR,
84 				strerror(TST_ERR));
85 	} else {
86 		tst_res(TFAIL, "unexpected error - %d : %s - "
87 				"expected %d", TST_ERR,
88 				strerror(TST_ERR), tcases[i].error);
89 	}
90 }
91 
setup(void)92 static void setup(void)
93 {
94 	int fildes;
95 	char nobody_uid[] = "nobody";
96 	struct passwd *ltpuser;
97 
98 	umask(0);
99 
100 	SAFE_CREAT(user2_fname, 0600);
101 
102 	/* Switch to nobody user for correct error code collection */
103 	ltpuser = getpwnam(nobody_uid);
104 	SAFE_SETGID(ltpuser->pw_gid);
105 	SAFE_SETUID(ltpuser->pw_uid);
106 
107 	fildes = SAFE_CREAT(existing_fname, 0600);
108 	close(fildes);
109 
110 	unmapped_fname = tst_get_bad_addr(NULL);
111 }
112 
113 static struct tst_test test = {
114 	.tcnt = ARRAY_SIZE(tcases),
115 	.needs_tmpdir = 1,
116 	.needs_root = 1,
117 	.setup = setup,
118 	.test = verify_open,
119 };
120