1 /*
2 * Copyright (c) 2026 The FreeBSD Foundation
3 *
4 * This software was written by Mark Johnston under sponsorship from
5 * the FreeBSD Foundation.
6 *
7 * SPDX-License-Identifier: BSD-2-Clause
8 */
9
10 #include <sys/stat.h>
11 #include <sys/mount.h>
12
13 #include <errno.h>
14 #include <fcntl.h>
15 #include <unistd.h>
16
17 #include <atf-c.h>
18
19 /*
20 * Verify that AT_RESOLVE_BENEATH is respected by various system calls.
21 */
22
23 static int
setup(void)24 setup(void)
25 {
26 int fd, tfd;
27
28 ATF_REQUIRE_EQ(0, mkdir("base", 0755));
29 ATF_REQUIRE_EQ(0, mkdir("outside", 0755));
30 ATF_REQUIRE((tfd = open("outside/target", O_CREAT | O_WRONLY, 0644)) >=
31 0);
32 ATF_REQUIRE(close(tfd) == 0);
33 ATF_REQUIRE_EQ(0, mkdir("outside/dir", 0755));
34 ATF_REQUIRE((tfd = open("base/file", O_CREAT | O_WRONLY, 0644)) >= 0);
35 ATF_REQUIRE(close(tfd) == 0);
36 ATF_REQUIRE_EQ(0, mkdir("base/subdir", 0755));
37 ATF_REQUIRE((fd = open("base", O_DIRECTORY | O_RDONLY)) >= 0);
38 return (fd);
39 }
40
41 ATF_TC_WITHOUT_HEAD(faccessat_beneath);
ATF_TC_BODY(faccessat_beneath,tc)42 ATF_TC_BODY(faccessat_beneath, tc)
43 {
44 int fd;
45
46 fd = setup();
47 ATF_REQUIRE_EQ(0,
48 faccessat(fd, "file", F_OK, AT_RESOLVE_BENEATH));
49 ATF_REQUIRE_ERRNO(ENOTCAPABLE,
50 faccessat(fd, "../outside/target", F_OK,
51 AT_RESOLVE_BENEATH) == -1);
52 ATF_REQUIRE(close(fd) == 0);
53 }
54
55 ATF_TC_WITHOUT_HEAD(chflagsat_beneath);
ATF_TC_BODY(chflagsat_beneath,tc)56 ATF_TC_BODY(chflagsat_beneath, tc)
57 {
58 int fd, ret;
59
60 fd = setup();
61 ret = chflagsat(fd, "file", UF_NODUMP, AT_RESOLVE_BENEATH);
62 if (ret != 0)
63 ATF_REQUIRE_EQ(EOPNOTSUPP, errno);
64 ATF_REQUIRE_ERRNO(ENOTCAPABLE,
65 chflagsat(fd, "../outside/target", UF_NODUMP,
66 AT_RESOLVE_BENEATH) == -1);
67 ATF_REQUIRE(close(fd) == 0);
68 }
69
70 ATF_TC_WITHOUT_HEAD(fchmodat_beneath);
ATF_TC_BODY(fchmodat_beneath,tc)71 ATF_TC_BODY(fchmodat_beneath, tc)
72 {
73 int fd;
74
75 fd = setup();
76 ATF_REQUIRE_EQ(0,
77 fchmodat(fd, "file", 0644, AT_RESOLVE_BENEATH));
78 ATF_REQUIRE_ERRNO(ENOTCAPABLE,
79 fchmodat(fd, "../outside/target", 0644,
80 AT_RESOLVE_BENEATH) == -1);
81 ATF_REQUIRE(close(fd) == 0);
82 }
83
84 ATF_TC_WITHOUT_HEAD(fchownat_beneath);
ATF_TC_BODY(fchownat_beneath,tc)85 ATF_TC_BODY(fchownat_beneath, tc)
86 {
87 int fd;
88
89 fd = setup();
90 ATF_REQUIRE_EQ(0,
91 fchownat(fd, "file", -1, -1, AT_RESOLVE_BENEATH));
92 ATF_REQUIRE_ERRNO(ENOTCAPABLE,
93 fchownat(fd, "../outside/target", 0, 0,
94 AT_RESOLVE_BENEATH) == -1);
95 ATF_REQUIRE(close(fd) == 0);
96 }
97
98 ATF_TC_WITHOUT_HEAD(utimensat_beneath);
ATF_TC_BODY(utimensat_beneath,tc)99 ATF_TC_BODY(utimensat_beneath, tc)
100 {
101 int fd;
102
103 fd = setup();
104 ATF_REQUIRE_EQ(0,
105 utimensat(fd, "file", NULL, AT_RESOLVE_BENEATH));
106 ATF_REQUIRE_ERRNO(ENOTCAPABLE,
107 utimensat(fd, "../outside/target", NULL,
108 AT_RESOLVE_BENEATH) == -1);
109 ATF_REQUIRE(close(fd) == 0);
110 }
111
112 ATF_TC_WITHOUT_HEAD(linkat_beneath);
ATF_TC_BODY(linkat_beneath,tc)113 ATF_TC_BODY(linkat_beneath, tc)
114 {
115 int fd;
116
117 fd = setup();
118 ATF_REQUIRE_EQ(0,
119 linkat(fd, "file", fd, "hardlink", AT_RESOLVE_BENEATH));
120 ATF_REQUIRE_ERRNO(ENOTCAPABLE,
121 linkat(fd, "../outside/target", fd, "hardlink2",
122 AT_RESOLVE_BENEATH) == -1);
123 ATF_REQUIRE(close(fd) == 0);
124 }
125
126 ATF_TC_WITHOUT_HEAD(unlinkat_beneath);
ATF_TC_BODY(unlinkat_beneath,tc)127 ATF_TC_BODY(unlinkat_beneath, tc)
128 {
129 int fd;
130
131 fd = setup();
132 ATF_REQUIRE_EQ(0,
133 unlinkat(fd, "file", AT_RESOLVE_BENEATH));
134 ATF_REQUIRE_ERRNO(ENOTCAPABLE,
135 unlinkat(fd, "../outside/target",
136 AT_RESOLVE_BENEATH) == -1);
137 ATF_REQUIRE(close(fd) == 0);
138 }
139
140 ATF_TC_WITHOUT_HEAD(unlinkat_rmdir_beneath);
ATF_TC_BODY(unlinkat_rmdir_beneath,tc)141 ATF_TC_BODY(unlinkat_rmdir_beneath, tc)
142 {
143 int fd;
144
145 fd = setup();
146 ATF_REQUIRE_EQ(0,
147 unlinkat(fd, "subdir",
148 AT_REMOVEDIR | AT_RESOLVE_BENEATH));
149 ATF_REQUIRE_ERRNO(ENOTCAPABLE,
150 unlinkat(fd, "../outside/dir",
151 AT_REMOVEDIR | AT_RESOLVE_BENEATH) == -1);
152 ATF_REQUIRE_EQ(0, access("outside/dir", F_OK));
153 ATF_REQUIRE(close(fd) == 0);
154 }
155
156 ATF_TC_WITHOUT_HEAD(funlinkat_beneath);
ATF_TC_BODY(funlinkat_beneath,tc)157 ATF_TC_BODY(funlinkat_beneath, tc)
158 {
159 int fd;
160
161 fd = setup();
162 ATF_REQUIRE_EQ(0,
163 funlinkat(fd, "file", FD_NONE, AT_RESOLVE_BENEATH));
164 ATF_REQUIRE_ERRNO(ENOTCAPABLE,
165 funlinkat(fd, "../outside/target", FD_NONE,
166 AT_RESOLVE_BENEATH) == -1);
167 ATF_REQUIRE(close(fd) == 0);
168 }
169
170 ATF_TC_WITHOUT_HEAD(funlinkat_rmdir_beneath);
ATF_TC_BODY(funlinkat_rmdir_beneath,tc)171 ATF_TC_BODY(funlinkat_rmdir_beneath, tc)
172 {
173 int fd;
174
175 fd = setup();
176 ATF_REQUIRE_EQ(0, mkdir("base/subdir2", 0755));
177 ATF_REQUIRE_EQ(0,
178 funlinkat(fd, "subdir2", FD_NONE,
179 AT_REMOVEDIR | AT_RESOLVE_BENEATH));
180 ATF_REQUIRE_ERRNO(ENOTCAPABLE,
181 funlinkat(fd, "../outside/dir", FD_NONE,
182 AT_REMOVEDIR | AT_RESOLVE_BENEATH) == -1);
183 ATF_REQUIRE_EQ(0, access("outside/dir", F_OK));
184 ATF_REQUIRE(close(fd) == 0);
185 }
186
187 ATF_TC(getfhat_beneath);
ATF_TC_HEAD(getfhat_beneath,tc)188 ATF_TC_HEAD(getfhat_beneath, tc)
189 {
190 atf_tc_set_md_var(tc, "require.user", "root");
191 }
ATF_TC_BODY(getfhat_beneath,tc)192 ATF_TC_BODY(getfhat_beneath, tc)
193 {
194 fhandle_t fh;
195 int fd;
196
197 fd = setup();
198 ATF_REQUIRE_EQ(0,
199 getfhat(fd, "file", &fh, AT_RESOLVE_BENEATH));
200 ATF_REQUIRE_ERRNO(ENOTCAPABLE,
201 getfhat(fd, "../outside/target", &fh,
202 AT_RESOLVE_BENEATH) == -1);
203 ATF_REQUIRE(close(fd) == 0);
204 }
205
ATF_TP_ADD_TCS(tp)206 ATF_TP_ADD_TCS(tp)
207 {
208 ATF_TP_ADD_TC(tp, faccessat_beneath);
209 ATF_TP_ADD_TC(tp, chflagsat_beneath);
210 ATF_TP_ADD_TC(tp, fchmodat_beneath);
211 ATF_TP_ADD_TC(tp, fchownat_beneath);
212 ATF_TP_ADD_TC(tp, utimensat_beneath);
213 ATF_TP_ADD_TC(tp, linkat_beneath);
214 ATF_TP_ADD_TC(tp, unlinkat_beneath);
215 ATF_TP_ADD_TC(tp, unlinkat_rmdir_beneath);
216 ATF_TP_ADD_TC(tp, funlinkat_beneath);
217 ATF_TP_ADD_TC(tp, funlinkat_rmdir_beneath);
218 ATF_TP_ADD_TC(tp, getfhat_beneath);
219 return (atf_no_error());
220 }
221