1 | /* Basic tests for _dl_find_object. |
2 | Copyright (C) 2021-2024 Free Software Foundation, Inc. |
3 | This file is part of the GNU C Library. |
4 | |
5 | The GNU C Library is free software; you can redistribute it and/or |
6 | modify it under the terms of the GNU Lesser General Public |
7 | License as published by the Free Software Foundation; either |
8 | version 2.1 of the License, or (at your option) any later version. |
9 | |
10 | The GNU C Library is distributed in the hope that it will be useful, |
11 | but WITHOUT ANY WARRANTY; without even the implied warranty of |
12 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
13 | Lesser General Public License for more details. |
14 | |
15 | You should have received a copy of the GNU Lesser General Public |
16 | License along with the GNU C Library; if not, see |
17 | <https://www.gnu.org/licenses/>. */ |
18 | |
19 | #include <dl-find_object.h> |
20 | #include <dlfcn.h> |
21 | #include <gnu/lib-names.h> |
22 | #include <ldsodefs.h> |
23 | #include <link.h> |
24 | #include <stdio.h> |
25 | #include <support/check.h> |
26 | #include <support/xdlfcn.h> |
27 | |
28 | /* Use data objects for testing, so that it is not necessary to decode |
29 | function descriptors on architectures that have them. */ |
30 | static char main_program_data; |
31 | |
32 | /* Computes the expected _dl_find_object result directly from the |
33 | map. */ |
34 | static void |
35 | from_map (struct link_map *l, struct dl_find_object *expected) |
36 | { |
37 | struct dl_find_object_internal internal; |
38 | _dl_find_object_from_map (l, result: &internal); |
39 | _dl_find_object_to_external (internal: &internal, external: expected); |
40 | } |
41 | |
42 | /* Compare _dl_find_object result at ADDRESS with *EXPECTED. */ |
43 | static void |
44 | check (void *address, |
45 | struct dl_find_object *expected, int line) |
46 | { |
47 | struct dl_find_object actual; |
48 | int ret = _dl_find_object (address: address, result: &actual); |
49 | if (expected == NULL) |
50 | { |
51 | if (ret != -1) |
52 | { |
53 | support_record_failure (); |
54 | printf (format: "%s:%d: unexpected success for %p\n" , |
55 | __FILE__, line, address); |
56 | } |
57 | return; |
58 | } |
59 | if (ret != 0) |
60 | { |
61 | support_record_failure (); |
62 | printf (format: "%s:%d: unexpected failure for %p\n" , |
63 | __FILE__, line, address); |
64 | return; |
65 | } |
66 | |
67 | if (actual.dlfo_flags != expected->dlfo_flags) |
68 | { |
69 | support_record_failure (); |
70 | printf (format: "%s:%d: error: %p: flags is %llu, expected %llu\n" , |
71 | __FILE__, line, address, |
72 | actual.dlfo_flags, expected->dlfo_flags); |
73 | } |
74 | if (expected->dlfo_link_map->l_contiguous) |
75 | { |
76 | /* If the mappings are not contiguous, the actual and execpted |
77 | mappings may differ, so this subtest will not work. */ |
78 | if (actual.dlfo_flags != expected->dlfo_flags) |
79 | { |
80 | support_record_failure (); |
81 | printf (format: "%s:%d: error: %p: map start is %p, expected %p\n" , |
82 | __FILE__, line, |
83 | address, actual.dlfo_map_start, expected->dlfo_map_start); |
84 | } |
85 | if (actual.dlfo_map_end != expected->dlfo_map_end) |
86 | { |
87 | support_record_failure (); |
88 | printf (format: "%s:%d: error: %p: map end is %p, expected %p\n" , |
89 | __FILE__, line, |
90 | address, actual.dlfo_map_end, expected->dlfo_map_end); |
91 | } |
92 | } |
93 | if (actual.dlfo_link_map != expected->dlfo_link_map) |
94 | { |
95 | support_record_failure (); |
96 | printf (format: "%s:%d: error: %p: link map is %p, expected %p\n" , |
97 | __FILE__, line, |
98 | address, actual.dlfo_link_map, expected->dlfo_link_map); |
99 | } |
100 | if (actual.dlfo_eh_frame != expected->dlfo_eh_frame) |
101 | { |
102 | support_record_failure (); |
103 | printf (format: "%s:%d: error: %p: EH frame is %p, expected %p\n" , |
104 | __FILE__, line, |
105 | address, actual.dlfo_eh_frame, expected->dlfo_eh_frame); |
106 | } |
107 | #if DLFO_STRUCT_HAS_EH_DBASE |
108 | if (actual.dlfo_eh_dbase != expected->dlfo_eh_dbase) |
109 | { |
110 | support_record_failure (); |
111 | printf ("%s:%d: error: %p: data base is %p, expected %p\n" , |
112 | __FILE__, line, |
113 | address, actual.dlfo_eh_dbase, expected->dlfo_eh_dbase); |
114 | } |
115 | #endif |
116 | #if DLFO_STRUCT_HAS_EH_COUNT |
117 | if (actual.dlfo_eh_count != expected->dlfo_eh_count) |
118 | { |
119 | support_record_failure (); |
120 | printf ("%s:%d: error: %p: count is %d, expected %d\n" , |
121 | __FILE__, line, |
122 | address, actual.dlfo_eh_count, expected->dlfo_eh_count); |
123 | } |
124 | #endif |
125 | } |
126 | |
127 | /* Check that unwind data for the main executable and the dynamic |
128 | linker can be found. */ |
129 | static void |
130 | check_initial (void) |
131 | { |
132 | #ifndef FOR_STATIC |
133 | /* Avoid direct reference, which could lead to copy relocations. */ |
134 | struct r_debug *debug = xdlsym (NULL, "_r_debug" ); |
135 | TEST_VERIFY_EXIT (debug != NULL); |
136 | char **tzname = xdlsym (NULL, "tzname" ); |
137 | |
138 | /* The main executable has an unnamed link map. */ |
139 | struct link_map *main_map = (struct link_map *) debug->r_map; |
140 | TEST_COMPARE_STRING (main_map->l_name, "" ); |
141 | |
142 | /* The link map of the dynamic linker. */ |
143 | struct link_map *rtld_map = xdlopen (LD_SO, RTLD_LAZY | RTLD_NOLOAD); |
144 | TEST_VERIFY_EXIT (rtld_map != NULL); |
145 | |
146 | /* The link map of libc.so. */ |
147 | struct link_map *libc_map = xdlopen (LIBC_SO, RTLD_LAZY | RTLD_NOLOAD); |
148 | TEST_VERIFY_EXIT (libc_map != NULL); |
149 | |
150 | struct dl_find_object expected; |
151 | |
152 | /* Data in the main program. */ |
153 | from_map (main_map, &expected); |
154 | check (&main_program_data, &expected, __LINE__); |
155 | /* Corner cases for the mapping. */ |
156 | check ((void *) main_map->l_map_start, &expected, __LINE__); |
157 | check ((void *) (main_map->l_map_end - 1), &expected, __LINE__); |
158 | |
159 | /* Data in the dynamic loader. */ |
160 | from_map (rtld_map, &expected); |
161 | check (debug, &expected, __LINE__); |
162 | check ((void *) rtld_map->l_map_start, &expected, __LINE__); |
163 | check ((void *) (rtld_map->l_map_end - 1), &expected, __LINE__); |
164 | |
165 | /* Data in libc. */ |
166 | from_map (libc_map, &expected); |
167 | check (tzname, &expected, __LINE__); |
168 | check ((void *) libc_map->l_map_start, &expected, __LINE__); |
169 | check ((void *) (libc_map->l_map_end - 1), &expected, __LINE__); |
170 | #endif |
171 | } |
172 | |
173 | static int |
174 | do_test (void) |
175 | { |
176 | { |
177 | struct dl_find_object dlfo = { }; |
178 | int ret = _dl_find_object (address: &main_program_data, result: &dlfo); |
179 | printf (format: "info: main program unwind data: %p (%d)\n" , |
180 | dlfo.dlfo_eh_frame, ret); |
181 | TEST_COMPARE (ret, 0); |
182 | TEST_VERIFY (dlfo.dlfo_eh_frame != NULL); |
183 | } |
184 | |
185 | check_initial (); |
186 | |
187 | /* dlopen-based test. First an object that can be dlclosed. */ |
188 | struct link_map *mod1 = xdlopen (filename: "tst-dl_find_object-mod1.so" , RTLD_NOW); |
189 | void *mod1_data = xdlsym (handle: mod1, symbol: "mod1_data" ); |
190 | void *map_start = (void *) mod1->l_map_start; |
191 | void *map_end = (void *) (mod1->l_map_end - 1); |
192 | check_initial (); |
193 | |
194 | struct dl_find_object expected; |
195 | from_map (l: mod1, expected: &expected); |
196 | check (address: mod1_data, expected: &expected, __LINE__); |
197 | check (address: map_start, expected: &expected, __LINE__); |
198 | check (address: map_end, expected: &expected, __LINE__); |
199 | |
200 | /* Unloading must make the data unavailable. */ |
201 | xdlclose (handle: mod1); |
202 | check_initial (); |
203 | check (address: mod1_data, NULL, __LINE__); |
204 | check (address: map_start, NULL, __LINE__); |
205 | check (address: map_end, NULL, __LINE__); |
206 | |
207 | /* Now try a NODELETE load. */ |
208 | struct link_map *mod2 = xdlopen (filename: "tst-dl_find_object-mod2.so" , RTLD_NOW); |
209 | void *mod2_data = xdlsym (handle: mod2, symbol: "mod2_data" ); |
210 | map_start = (void *) mod2->l_map_start; |
211 | map_end = (void *) (mod2->l_map_end - 1); |
212 | check_initial (); |
213 | from_map (l: mod2, expected: &expected); |
214 | check (address: mod2_data, expected: &expected, __LINE__); |
215 | check (address: map_start, expected: &expected, __LINE__); |
216 | check (address: map_end, expected: &expected, __LINE__); |
217 | dlclose (handle: mod2); /* Does nothing due to NODELETE. */ |
218 | check_initial (); |
219 | check (address: mod2_data, expected: &expected, __LINE__); |
220 | check (address: map_start, expected: &expected, __LINE__); |
221 | check (address: map_end, expected: &expected, __LINE__); |
222 | |
223 | /* Now load again the first module. */ |
224 | mod1 = xdlopen (filename: "tst-dl_find_object-mod1.so" , RTLD_NOW); |
225 | mod1_data = xdlsym (handle: mod1, symbol: "mod1_data" ); |
226 | map_start = (void *) mod1->l_map_start; |
227 | map_end = (void *) (mod1->l_map_end - 1); |
228 | check_initial (); |
229 | from_map (l: mod1, expected: &expected); |
230 | check (address: mod1_data, expected: &expected, __LINE__); |
231 | check (address: map_start, expected: &expected, __LINE__); |
232 | check (address: map_end, expected: &expected, __LINE__); |
233 | |
234 | /* Check that _dl_find_object works from a shared object (mostly for |
235 | static dlopen). */ |
236 | __typeof (_dl_find_object) *find_object |
237 | = *(void **) xdlsym (handle: mod2, symbol: "find_object" ); |
238 | struct dl_find_object actual; |
239 | TEST_COMPARE (find_object (&main_program_data, &actual), 0); |
240 | check (address: &main_program_data, expected: &actual, __LINE__); /* Reversed check. */ |
241 | |
242 | return 0; |
243 | } |
244 | |
245 | #include <support/test-driver.c> |
246 | |