1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  * Copyright (c) 2000 Silicon Graphics, Inc.  All Rights Reserved.
4  */
5 
6 /*
7  * Description:
8  * The testcase checks the various errnos of the unlink(2).
9  * 1) unlink() returns EACCES when deleting file in unwritable directory
10  *    as an unprivileged user.
11  * 2) unlink() returns EACCES when deleting file in "unsearchable directory
12  *    as an unprivileged user.
13  * 3) unlink() returns EISDIR when deleting directory for root
14  * 4) unlink() returns EISDIR when deleting directory for regular user
15  */
16 
17 #include <errno.h>
18 #include <stdlib.h>
19 #include <sys/types.h>
20 #include <pwd.h>
21 #include "tst_test.h"
22 
23 static struct passwd *pw;
24 
25 static struct test_case_t {
26 	char *name;
27 	char *desc;
28 	int exp_errno;
29 	int exp_user;
30 } tcases[] = {
31 	{"unwrite_dir/file", "unwritable directory", EACCES, 1},
32 	{"unsearch_dir/file", "unsearchable directory", EACCES, 1},
33 	{"regdir", "directory", EISDIR, 0},
34 	{"regdir", "directory", EISDIR, 1},
35 };
36 
verify_unlink(struct test_case_t * tc)37 static void verify_unlink(struct test_case_t *tc)
38 {
39 	TEST(unlink(tc->name));
40 	if (TST_RET != -1) {
41 		tst_res(TFAIL, "unlink(<%s>) succeeded unexpectedly",
42 			tc->desc);
43 		return;
44 	}
45 
46 	if (TST_ERR == tc->exp_errno) {
47 		tst_res(TPASS | TTERRNO, "unlink(<%s>) failed as expected",
48 			tc->desc);
49 	} else {
50 		tst_res(TFAIL | TTERRNO,
51 			"unlink(<%s>) failed, expected errno: %s",
52 			tc->desc, tst_strerrno(tc->exp_errno));
53 	}
54 }
55 
do_unlink(unsigned int n)56 static void do_unlink(unsigned int n)
57 {
58 	struct test_case_t *cases = &tcases[n];
59 	pid_t pid;
60 
61 	if (cases->exp_user) {
62 		pid = SAFE_FORK();
63 		if (!pid) {
64 			SAFE_SETUID(pw->pw_uid);
65 			verify_unlink(cases);
66 			exit(0);
67 		}
68 
69 		SAFE_WAITPID(pid, NULL, 0);
70 	} else {
71 		verify_unlink(cases);
72 	}
73 }
74 
setup(void)75 static void setup(void)
76 {
77 	SAFE_MKDIR("unwrite_dir", 0777);
78 	SAFE_TOUCH("unwrite_dir/file", 0777, NULL);
79 	SAFE_CHMOD("unwrite_dir", 0555);
80 
81 	SAFE_MKDIR("unsearch_dir", 0777);
82 	SAFE_TOUCH("unsearch_dir/file", 0777, NULL);
83 	SAFE_CHMOD("unsearch_dir", 0666);
84 
85 	SAFE_MKDIR("regdir", 0777);
86 
87 	pw = SAFE_GETPWNAM("nobody");
88 }
89 
90 static struct tst_test test = {
91 	.needs_root = 1,
92 	.forks_child = 1,
93 	.needs_tmpdir = 1,
94 	.setup = setup,
95 	.tcnt = ARRAY_SIZE(tcases),
96 	.test = do_unlink,
97 };
98