Commit | Line | Data |
---|---|---|
ab31aa69 | 1 | /* Handle SVR4 shared libraries for GDB, the GNU Debugger. |
2f4950cd | 2 | |
42a4f53d | 3 | Copyright (C) 1990-2019 Free Software Foundation, Inc. |
13437d4b KB |
4 | |
5 | This file is part of GDB. | |
6 | ||
7 | This program is free software; you can redistribute it and/or modify | |
8 | it under the terms of the GNU General Public License as published by | |
a9762ec7 | 9 | the Free Software Foundation; either version 3 of the License, or |
13437d4b KB |
10 | (at your option) any later version. |
11 | ||
12 | This program is distributed in the hope that it will be useful, | |
13 | but WITHOUT ANY WARRANTY; without even the implied warranty of | |
14 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | |
15 | GNU General Public License for more details. | |
16 | ||
17 | You should have received a copy of the GNU General Public License | |
a9762ec7 | 18 | along with this program. If not, see <http://www.gnu.org/licenses/>. */ |
13437d4b | 19 | |
13437d4b KB |
20 | #include "defs.h" |
21 | ||
13437d4b | 22 | #include "elf/external.h" |
21479ded | 23 | #include "elf/common.h" |
f7856c8f | 24 | #include "elf/mips.h" |
13437d4b KB |
25 | |
26 | #include "symtab.h" | |
27 | #include "bfd.h" | |
28 | #include "symfile.h" | |
29 | #include "objfiles.h" | |
30 | #include "gdbcore.h" | |
13437d4b | 31 | #include "target.h" |
13437d4b | 32 | #include "inferior.h" |
45741a9c | 33 | #include "infrun.h" |
fb14de7b | 34 | #include "regcache.h" |
2020b7ab | 35 | #include "gdbthread.h" |
76727919 | 36 | #include "observable.h" |
13437d4b KB |
37 | |
38 | #include "solist.h" | |
bba93f6c | 39 | #include "solib.h" |
13437d4b KB |
40 | #include "solib-svr4.h" |
41 | ||
2f4950cd | 42 | #include "bfd-target.h" |
cc10cae3 | 43 | #include "elf-bfd.h" |
2f4950cd | 44 | #include "exec.h" |
8d4e36ba | 45 | #include "auxv.h" |
695c3173 | 46 | #include "gdb_bfd.h" |
f9e14852 | 47 | #include "probe.h" |
2f4950cd | 48 | |
e5e2b9ff | 49 | static struct link_map_offsets *svr4_fetch_link_map_offsets (void); |
d5a921c9 | 50 | static int svr4_have_link_map_offsets (void); |
9f2982ff | 51 | static void svr4_relocate_main_executable (void); |
f9e14852 | 52 | static void svr4_free_library_list (void *p_list); |
7905fc35 | 53 | static void probes_table_remove_objfile_probes (struct objfile *objfile); |
1c4dcb57 | 54 | |
13437d4b KB |
55 | /* On SVR4 systems, a list of symbols in the dynamic linker where |
56 | GDB can try to place a breakpoint to monitor shared library | |
57 | events. | |
58 | ||
59 | If none of these symbols are found, or other errors occur, then | |
60 | SVR4 systems will fall back to using a symbol as the "startup | |
61 | mapping complete" breakpoint address. */ | |
62 | ||
bc043ef3 | 63 | static const char * const solib_break_names[] = |
13437d4b KB |
64 | { |
65 | "r_debug_state", | |
66 | "_r_debug_state", | |
67 | "_dl_debug_state", | |
68 | "rtld_db_dlactivity", | |
4c7dcb84 | 69 | "__dl_rtld_db_dlactivity", |
1f72e589 | 70 | "_rtld_debug_state", |
4c0122c8 | 71 | |
13437d4b KB |
72 | NULL |
73 | }; | |
13437d4b | 74 | |
bc043ef3 | 75 | static const char * const bkpt_names[] = |
13437d4b | 76 | { |
13437d4b | 77 | "_start", |
ad3dcc5c | 78 | "__start", |
13437d4b KB |
79 | "main", |
80 | NULL | |
81 | }; | |
13437d4b | 82 | |
bc043ef3 | 83 | static const char * const main_name_list[] = |
13437d4b KB |
84 | { |
85 | "main_$main", | |
86 | NULL | |
87 | }; | |
88 | ||
f9e14852 GB |
89 | /* What to do when a probe stop occurs. */ |
90 | ||
91 | enum probe_action | |
92 | { | |
93 | /* Something went seriously wrong. Stop using probes and | |
94 | revert to using the older interface. */ | |
95 | PROBES_INTERFACE_FAILED, | |
96 | ||
97 | /* No action is required. The shared object list is still | |
98 | valid. */ | |
99 | DO_NOTHING, | |
100 | ||
101 | /* The shared object list should be reloaded entirely. */ | |
102 | FULL_RELOAD, | |
103 | ||
104 | /* Attempt to incrementally update the shared object list. If | |
105 | the update fails or is not possible, fall back to reloading | |
106 | the list in full. */ | |
107 | UPDATE_OR_RELOAD, | |
108 | }; | |
109 | ||
110 | /* A probe's name and its associated action. */ | |
111 | ||
112 | struct probe_info | |
113 | { | |
114 | /* The name of the probe. */ | |
115 | const char *name; | |
116 | ||
117 | /* What to do when a probe stop occurs. */ | |
118 | enum probe_action action; | |
119 | }; | |
120 | ||
121 | /* A list of named probes and their associated actions. If all | |
122 | probes are present in the dynamic linker then the probes-based | |
123 | interface will be used. */ | |
124 | ||
125 | static const struct probe_info probe_info[] = | |
126 | { | |
127 | { "init_start", DO_NOTHING }, | |
128 | { "init_complete", FULL_RELOAD }, | |
129 | { "map_start", DO_NOTHING }, | |
130 | { "map_failed", DO_NOTHING }, | |
131 | { "reloc_complete", UPDATE_OR_RELOAD }, | |
132 | { "unmap_start", DO_NOTHING }, | |
133 | { "unmap_complete", FULL_RELOAD }, | |
134 | }; | |
135 | ||
136 | #define NUM_PROBES ARRAY_SIZE (probe_info) | |
137 | ||
4d7b2d5b JB |
138 | /* Return non-zero if GDB_SO_NAME and INFERIOR_SO_NAME represent |
139 | the same shared library. */ | |
140 | ||
141 | static int | |
142 | svr4_same_1 (const char *gdb_so_name, const char *inferior_so_name) | |
143 | { | |
144 | if (strcmp (gdb_so_name, inferior_so_name) == 0) | |
145 | return 1; | |
146 | ||
147 | /* On Solaris, when starting inferior we think that dynamic linker is | |
d989b283 PP |
148 | /usr/lib/ld.so.1, but later on, the table of loaded shared libraries |
149 | contains /lib/ld.so.1. Sometimes one file is a link to another, but | |
4d7b2d5b JB |
150 | sometimes they have identical content, but are not linked to each |
151 | other. We don't restrict this check for Solaris, but the chances | |
152 | of running into this situation elsewhere are very low. */ | |
153 | if (strcmp (gdb_so_name, "/usr/lib/ld.so.1") == 0 | |
154 | && strcmp (inferior_so_name, "/lib/ld.so.1") == 0) | |
155 | return 1; | |
156 | ||
7307a73a | 157 | /* Similarly, we observed the same issue with amd64 and sparcv9, but with |
4d7b2d5b | 158 | different locations. */ |
7307a73a RO |
159 | if (strcmp (gdb_so_name, "/usr/lib/amd64/ld.so.1") == 0 |
160 | && strcmp (inferior_so_name, "/lib/amd64/ld.so.1") == 0) | |
161 | return 1; | |
162 | ||
4d7b2d5b JB |
163 | if (strcmp (gdb_so_name, "/usr/lib/sparcv9/ld.so.1") == 0 |
164 | && strcmp (inferior_so_name, "/lib/sparcv9/ld.so.1") == 0) | |
165 | return 1; | |
166 | ||
167 | return 0; | |
168 | } | |
169 | ||
170 | static int | |
171 | svr4_same (struct so_list *gdb, struct so_list *inferior) | |
172 | { | |
173 | return (svr4_same_1 (gdb->so_original_name, inferior->so_original_name)); | |
174 | } | |
175 | ||
a7961323 | 176 | static std::unique_ptr<lm_info_svr4> |
3957565a | 177 | lm_info_read (CORE_ADDR lm_addr) |
13437d4b | 178 | { |
4b188b9f | 179 | struct link_map_offsets *lmo = svr4_fetch_link_map_offsets (); |
a7961323 | 180 | std::unique_ptr<lm_info_svr4> lm_info; |
3957565a | 181 | |
a7961323 | 182 | gdb::byte_vector lm (lmo->link_map_size); |
3957565a | 183 | |
a7961323 TT |
184 | if (target_read_memory (lm_addr, lm.data (), lmo->link_map_size) != 0) |
185 | warning (_("Error reading shared library list entry at %s"), | |
186 | paddress (target_gdbarch (), lm_addr)); | |
3957565a JK |
187 | else |
188 | { | |
f5656ead | 189 | struct type *ptr_type = builtin_type (target_gdbarch ())->builtin_data_ptr; |
13437d4b | 190 | |
a7961323 | 191 | lm_info.reset (new lm_info_svr4); |
3957565a JK |
192 | lm_info->lm_addr = lm_addr; |
193 | ||
194 | lm_info->l_addr_inferior = extract_typed_address (&lm[lmo->l_addr_offset], | |
195 | ptr_type); | |
196 | lm_info->l_ld = extract_typed_address (&lm[lmo->l_ld_offset], ptr_type); | |
197 | lm_info->l_next = extract_typed_address (&lm[lmo->l_next_offset], | |
198 | ptr_type); | |
199 | lm_info->l_prev = extract_typed_address (&lm[lmo->l_prev_offset], | |
200 | ptr_type); | |
201 | lm_info->l_name = extract_typed_address (&lm[lmo->l_name_offset], | |
202 | ptr_type); | |
203 | } | |
204 | ||
3957565a | 205 | return lm_info; |
13437d4b KB |
206 | } |
207 | ||
cc10cae3 | 208 | static int |
b23518f0 | 209 | has_lm_dynamic_from_link_map (void) |
cc10cae3 AO |
210 | { |
211 | struct link_map_offsets *lmo = svr4_fetch_link_map_offsets (); | |
212 | ||
cfaefc65 | 213 | return lmo->l_ld_offset >= 0; |
cc10cae3 AO |
214 | } |
215 | ||
cc10cae3 | 216 | static CORE_ADDR |
f65ce5fb | 217 | lm_addr_check (const struct so_list *so, bfd *abfd) |
cc10cae3 | 218 | { |
d0e449a1 SM |
219 | lm_info_svr4 *li = (lm_info_svr4 *) so->lm_info; |
220 | ||
221 | if (!li->l_addr_p) | |
cc10cae3 AO |
222 | { |
223 | struct bfd_section *dyninfo_sect; | |
28f34a8f | 224 | CORE_ADDR l_addr, l_dynaddr, dynaddr; |
cc10cae3 | 225 | |
d0e449a1 | 226 | l_addr = li->l_addr_inferior; |
cc10cae3 | 227 | |
b23518f0 | 228 | if (! abfd || ! has_lm_dynamic_from_link_map ()) |
cc10cae3 AO |
229 | goto set_addr; |
230 | ||
d0e449a1 | 231 | l_dynaddr = li->l_ld; |
cc10cae3 AO |
232 | |
233 | dyninfo_sect = bfd_get_section_by_name (abfd, ".dynamic"); | |
234 | if (dyninfo_sect == NULL) | |
235 | goto set_addr; | |
236 | ||
237 | dynaddr = bfd_section_vma (abfd, dyninfo_sect); | |
238 | ||
239 | if (dynaddr + l_addr != l_dynaddr) | |
240 | { | |
28f34a8f | 241 | CORE_ADDR align = 0x1000; |
4e1fc9c9 | 242 | CORE_ADDR minpagesize = align; |
28f34a8f | 243 | |
cc10cae3 AO |
244 | if (bfd_get_flavour (abfd) == bfd_target_elf_flavour) |
245 | { | |
246 | Elf_Internal_Ehdr *ehdr = elf_tdata (abfd)->elf_header; | |
247 | Elf_Internal_Phdr *phdr = elf_tdata (abfd)->phdr; | |
248 | int i; | |
249 | ||
250 | align = 1; | |
251 | ||
252 | for (i = 0; i < ehdr->e_phnum; i++) | |
253 | if (phdr[i].p_type == PT_LOAD && phdr[i].p_align > align) | |
254 | align = phdr[i].p_align; | |
4e1fc9c9 JK |
255 | |
256 | minpagesize = get_elf_backend_data (abfd)->minpagesize; | |
cc10cae3 AO |
257 | } |
258 | ||
259 | /* Turn it into a mask. */ | |
260 | align--; | |
261 | ||
262 | /* If the changes match the alignment requirements, we | |
263 | assume we're using a core file that was generated by the | |
264 | same binary, just prelinked with a different base offset. | |
265 | If it doesn't match, we may have a different binary, the | |
266 | same binary with the dynamic table loaded at an unrelated | |
267 | location, or anything, really. To avoid regressions, | |
268 | don't adjust the base offset in the latter case, although | |
269 | odds are that, if things really changed, debugging won't | |
5c0d192f JK |
270 | quite work. |
271 | ||
272 | One could expect more the condition | |
273 | ((l_addr & align) == 0 && ((l_dynaddr - dynaddr) & align) == 0) | |
274 | but the one below is relaxed for PPC. The PPC kernel supports | |
275 | either 4k or 64k page sizes. To be prepared for 64k pages, | |
276 | PPC ELF files are built using an alignment requirement of 64k. | |
277 | However, when running on a kernel supporting 4k pages, the memory | |
278 | mapping of the library may not actually happen on a 64k boundary! | |
279 | ||
280 | (In the usual case where (l_addr & align) == 0, this check is | |
4e1fc9c9 JK |
281 | equivalent to the possibly expected check above.) |
282 | ||
283 | Even on PPC it must be zero-aligned at least for MINPAGESIZE. */ | |
5c0d192f | 284 | |
02835898 JK |
285 | l_addr = l_dynaddr - dynaddr; |
286 | ||
4e1fc9c9 JK |
287 | if ((l_addr & (minpagesize - 1)) == 0 |
288 | && (l_addr & align) == ((l_dynaddr - dynaddr) & align)) | |
cc10cae3 | 289 | { |
701ed6dc | 290 | if (info_verbose) |
ccf26247 JK |
291 | printf_unfiltered (_("Using PIC (Position Independent Code) " |
292 | "prelink displacement %s for \"%s\".\n"), | |
f5656ead | 293 | paddress (target_gdbarch (), l_addr), |
ccf26247 | 294 | so->so_name); |
cc10cae3 | 295 | } |
79d4c408 | 296 | else |
02835898 JK |
297 | { |
298 | /* There is no way to verify the library file matches. prelink | |
299 | can during prelinking of an unprelinked file (or unprelinking | |
300 | of a prelinked file) shift the DYNAMIC segment by arbitrary | |
301 | offset without any page size alignment. There is no way to | |
302 | find out the ELF header and/or Program Headers for a limited | |
303 | verification if it they match. One could do a verification | |
304 | of the DYNAMIC segment. Still the found address is the best | |
305 | one GDB could find. */ | |
306 | ||
307 | warning (_(".dynamic section for \"%s\" " | |
308 | "is not at the expected address " | |
309 | "(wrong library or version mismatch?)"), so->so_name); | |
310 | } | |
cc10cae3 AO |
311 | } |
312 | ||
313 | set_addr: | |
d0e449a1 SM |
314 | li->l_addr = l_addr; |
315 | li->l_addr_p = 1; | |
cc10cae3 AO |
316 | } |
317 | ||
d0e449a1 | 318 | return li->l_addr; |
cc10cae3 AO |
319 | } |
320 | ||
6c95b8df | 321 | /* Per pspace SVR4 specific data. */ |
13437d4b | 322 | |
1a816a87 PA |
323 | struct svr4_info |
324 | { | |
09232438 TT |
325 | svr4_info () = default; |
326 | ~svr4_info (); | |
327 | ||
328 | /* Base of dynamic linker structures. */ | |
329 | CORE_ADDR debug_base = 0; | |
1a816a87 PA |
330 | |
331 | /* Validity flag for debug_loader_offset. */ | |
09232438 | 332 | int debug_loader_offset_p = 0; |
1a816a87 PA |
333 | |
334 | /* Load address for the dynamic linker, inferred. */ | |
09232438 | 335 | CORE_ADDR debug_loader_offset = 0; |
1a816a87 PA |
336 | |
337 | /* Name of the dynamic linker, valid if debug_loader_offset_p. */ | |
09232438 | 338 | char *debug_loader_name = nullptr; |
1a816a87 PA |
339 | |
340 | /* Load map address for the main executable. */ | |
09232438 | 341 | CORE_ADDR main_lm_addr = 0; |
1a816a87 | 342 | |
09232438 TT |
343 | CORE_ADDR interp_text_sect_low = 0; |
344 | CORE_ADDR interp_text_sect_high = 0; | |
345 | CORE_ADDR interp_plt_sect_low = 0; | |
346 | CORE_ADDR interp_plt_sect_high = 0; | |
f9e14852 GB |
347 | |
348 | /* Nonzero if the list of objects was last obtained from the target | |
349 | via qXfer:libraries-svr4:read. */ | |
09232438 | 350 | int using_xfer = 0; |
f9e14852 GB |
351 | |
352 | /* Table of struct probe_and_action instances, used by the | |
353 | probes-based interface to map breakpoint addresses to probes | |
354 | and their associated actions. Lookup is performed using | |
935676c9 | 355 | probe_and_action->prob->address. */ |
09232438 | 356 | htab_up probes_table; |
f9e14852 GB |
357 | |
358 | /* List of objects loaded into the inferior, used by the probes- | |
359 | based interface. */ | |
09232438 | 360 | struct so_list *solib_list = nullptr; |
6c95b8df | 361 | }; |
1a816a87 | 362 | |
6c95b8df | 363 | /* Per-program-space data key. */ |
09232438 | 364 | static const struct program_space_key<svr4_info> solib_svr4_pspace_data; |
1a816a87 | 365 | |
f9e14852 GB |
366 | /* Free the probes table. */ |
367 | ||
368 | static void | |
369 | free_probes_table (struct svr4_info *info) | |
370 | { | |
09232438 | 371 | info->probes_table.reset (nullptr); |
f9e14852 GB |
372 | } |
373 | ||
374 | /* Free the solib list. */ | |
375 | ||
376 | static void | |
377 | free_solib_list (struct svr4_info *info) | |
378 | { | |
379 | svr4_free_library_list (&info->solib_list); | |
380 | info->solib_list = NULL; | |
381 | } | |
382 | ||
09232438 | 383 | svr4_info::~svr4_info () |
1a816a87 | 384 | { |
09232438 | 385 | free_solib_list (this); |
1a816a87 PA |
386 | } |
387 | ||
d70cc3ba SM |
388 | /* Get the svr4 data for program space PSPACE. If none is found yet, add it now. |
389 | This function always returns a valid object. */ | |
34439770 | 390 | |
6c95b8df | 391 | static struct svr4_info * |
d70cc3ba | 392 | get_svr4_info (program_space *pspace) |
1a816a87 | 393 | { |
09232438 | 394 | struct svr4_info *info = solib_svr4_pspace_data.get (pspace); |
1a816a87 | 395 | |
09232438 TT |
396 | if (info == NULL) |
397 | info = solib_svr4_pspace_data.emplace (pspace); | |
34439770 | 398 | |
6c95b8df | 399 | return info; |
1a816a87 | 400 | } |
93a57060 | 401 | |
13437d4b KB |
402 | /* Local function prototypes */ |
403 | ||
bc043ef3 | 404 | static int match_main (const char *); |
13437d4b | 405 | |
97ec2c2f | 406 | /* Read program header TYPE from inferior memory. The header is found |
17658d46 | 407 | by scanning the OS auxiliary vector. |
97ec2c2f | 408 | |
09919ac2 JK |
409 | If TYPE == -1, return the program headers instead of the contents of |
410 | one program header. | |
411 | ||
17658d46 SM |
412 | Return vector of bytes holding the program header contents, or an empty |
413 | optional on failure. If successful and P_ARCH_SIZE is non-NULL, the target | |
414 | architecture size (32-bit or 64-bit) is returned to *P_ARCH_SIZE. Likewise, | |
415 | the base address of the section is returned in *BASE_ADDR. */ | |
97ec2c2f | 416 | |
17658d46 SM |
417 | static gdb::optional<gdb::byte_vector> |
418 | read_program_header (int type, int *p_arch_size, CORE_ADDR *base_addr) | |
97ec2c2f | 419 | { |
f5656ead | 420 | enum bfd_endian byte_order = gdbarch_byte_order (target_gdbarch ()); |
43136979 | 421 | CORE_ADDR at_phdr, at_phent, at_phnum, pt_phdr = 0; |
97ec2c2f UW |
422 | int arch_size, sect_size; |
423 | CORE_ADDR sect_addr; | |
43136979 | 424 | int pt_phdr_p = 0; |
97ec2c2f UW |
425 | |
426 | /* Get required auxv elements from target. */ | |
8b88a78e | 427 | if (target_auxv_search (current_top_target (), AT_PHDR, &at_phdr) <= 0) |
17658d46 | 428 | return {}; |
8b88a78e | 429 | if (target_auxv_search (current_top_target (), AT_PHENT, &at_phent) <= 0) |
17658d46 | 430 | return {}; |
8b88a78e | 431 | if (target_auxv_search (current_top_target (), AT_PHNUM, &at_phnum) <= 0) |
17658d46 | 432 | return {}; |
97ec2c2f | 433 | if (!at_phdr || !at_phnum) |
17658d46 | 434 | return {}; |
97ec2c2f UW |
435 | |
436 | /* Determine ELF architecture type. */ | |
437 | if (at_phent == sizeof (Elf32_External_Phdr)) | |
438 | arch_size = 32; | |
439 | else if (at_phent == sizeof (Elf64_External_Phdr)) | |
440 | arch_size = 64; | |
441 | else | |
17658d46 | 442 | return {}; |
97ec2c2f | 443 | |
09919ac2 JK |
444 | /* Find the requested segment. */ |
445 | if (type == -1) | |
446 | { | |
447 | sect_addr = at_phdr; | |
448 | sect_size = at_phent * at_phnum; | |
449 | } | |
450 | else if (arch_size == 32) | |
97ec2c2f UW |
451 | { |
452 | Elf32_External_Phdr phdr; | |
453 | int i; | |
454 | ||
455 | /* Search for requested PHDR. */ | |
456 | for (i = 0; i < at_phnum; i++) | |
457 | { | |
43136979 AR |
458 | int p_type; |
459 | ||
97ec2c2f UW |
460 | if (target_read_memory (at_phdr + i * sizeof (phdr), |
461 | (gdb_byte *)&phdr, sizeof (phdr))) | |
17658d46 | 462 | return {}; |
97ec2c2f | 463 | |
43136979 AR |
464 | p_type = extract_unsigned_integer ((gdb_byte *) phdr.p_type, |
465 | 4, byte_order); | |
466 | ||
467 | if (p_type == PT_PHDR) | |
468 | { | |
469 | pt_phdr_p = 1; | |
470 | pt_phdr = extract_unsigned_integer ((gdb_byte *) phdr.p_vaddr, | |
471 | 4, byte_order); | |
472 | } | |
473 | ||
474 | if (p_type == type) | |
97ec2c2f UW |
475 | break; |
476 | } | |
477 | ||
478 | if (i == at_phnum) | |
17658d46 | 479 | return {}; |
97ec2c2f UW |
480 | |
481 | /* Retrieve address and size. */ | |
e17a4113 UW |
482 | sect_addr = extract_unsigned_integer ((gdb_byte *)phdr.p_vaddr, |
483 | 4, byte_order); | |
484 | sect_size = extract_unsigned_integer ((gdb_byte *)phdr.p_memsz, | |
485 | 4, byte_order); | |
97ec2c2f UW |
486 | } |
487 | else | |
488 | { | |
489 | Elf64_External_Phdr phdr; | |
490 | int i; | |
491 | ||
492 | /* Search for requested PHDR. */ | |
493 | for (i = 0; i < at_phnum; i++) | |
494 | { | |
43136979 AR |
495 | int p_type; |
496 | ||
97ec2c2f UW |
497 | if (target_read_memory (at_phdr + i * sizeof (phdr), |
498 | (gdb_byte *)&phdr, sizeof (phdr))) | |
17658d46 | 499 | return {}; |
97ec2c2f | 500 | |
43136979 AR |
501 | p_type = extract_unsigned_integer ((gdb_byte *) phdr.p_type, |
502 | 4, byte_order); | |
503 | ||
504 | if (p_type == PT_PHDR) | |
505 | { | |
506 | pt_phdr_p = 1; | |
507 | pt_phdr = extract_unsigned_integer ((gdb_byte *) phdr.p_vaddr, | |
508 | 8, byte_order); | |
509 | } | |
510 | ||
511 | if (p_type == type) | |
97ec2c2f UW |
512 | break; |
513 | } | |
514 | ||
515 | if (i == at_phnum) | |
17658d46 | 516 | return {}; |
97ec2c2f UW |
517 | |
518 | /* Retrieve address and size. */ | |
e17a4113 UW |
519 | sect_addr = extract_unsigned_integer ((gdb_byte *)phdr.p_vaddr, |
520 | 8, byte_order); | |
521 | sect_size = extract_unsigned_integer ((gdb_byte *)phdr.p_memsz, | |
522 | 8, byte_order); | |
97ec2c2f UW |
523 | } |
524 | ||
43136979 AR |
525 | /* PT_PHDR is optional, but we really need it |
526 | for PIE to make this work in general. */ | |
527 | ||
528 | if (pt_phdr_p) | |
529 | { | |
530 | /* at_phdr is real address in memory. pt_phdr is what pheader says it is. | |
531 | Relocation offset is the difference between the two. */ | |
532 | sect_addr = sect_addr + (at_phdr - pt_phdr); | |
533 | } | |
534 | ||
97ec2c2f | 535 | /* Read in requested program header. */ |
17658d46 SM |
536 | gdb::byte_vector buf (sect_size); |
537 | if (target_read_memory (sect_addr, buf.data (), sect_size)) | |
538 | return {}; | |
97ec2c2f UW |
539 | |
540 | if (p_arch_size) | |
541 | *p_arch_size = arch_size; | |
a738da3a MF |
542 | if (base_addr) |
543 | *base_addr = sect_addr; | |
97ec2c2f UW |
544 | |
545 | return buf; | |
546 | } | |
547 | ||
548 | ||
549 | /* Return program interpreter string. */ | |
17658d46 | 550 | static gdb::optional<gdb::byte_vector> |
97ec2c2f UW |
551 | find_program_interpreter (void) |
552 | { | |
97ec2c2f UW |
553 | /* If we have an exec_bfd, use its section table. */ |
554 | if (exec_bfd | |
555 | && bfd_get_flavour (exec_bfd) == bfd_target_elf_flavour) | |
556 | { | |
557 | struct bfd_section *interp_sect; | |
558 | ||
559 | interp_sect = bfd_get_section_by_name (exec_bfd, ".interp"); | |
560 | if (interp_sect != NULL) | |
561 | { | |
97ec2c2f UW |
562 | int sect_size = bfd_section_size (exec_bfd, interp_sect); |
563 | ||
17658d46 SM |
564 | gdb::byte_vector buf (sect_size); |
565 | bfd_get_section_contents (exec_bfd, interp_sect, buf.data (), 0, | |
566 | sect_size); | |
567 | return buf; | |
97ec2c2f UW |
568 | } |
569 | } | |
570 | ||
17658d46 SM |
571 | /* If we didn't find it, use the target auxiliary vector. */ |
572 | return read_program_header (PT_INTERP, NULL, NULL); | |
97ec2c2f UW |
573 | } |
574 | ||
575 | ||
b6d7a4bf SM |
576 | /* Scan for DESIRED_DYNTAG in .dynamic section of ABFD. If DESIRED_DYNTAG is |
577 | found, 1 is returned and the corresponding PTR is set. */ | |
3a40aaa0 UW |
578 | |
579 | static int | |
a738da3a MF |
580 | scan_dyntag (const int desired_dyntag, bfd *abfd, CORE_ADDR *ptr, |
581 | CORE_ADDR *ptr_addr) | |
3a40aaa0 UW |
582 | { |
583 | int arch_size, step, sect_size; | |
b6d7a4bf | 584 | long current_dyntag; |
b381ea14 | 585 | CORE_ADDR dyn_ptr, dyn_addr; |
65728c26 | 586 | gdb_byte *bufend, *bufstart, *buf; |
3a40aaa0 UW |
587 | Elf32_External_Dyn *x_dynp_32; |
588 | Elf64_External_Dyn *x_dynp_64; | |
589 | struct bfd_section *sect; | |
61f0d762 | 590 | struct target_section *target_section; |
3a40aaa0 UW |
591 | |
592 | if (abfd == NULL) | |
593 | return 0; | |
0763ab81 PA |
594 | |
595 | if (bfd_get_flavour (abfd) != bfd_target_elf_flavour) | |
596 | return 0; | |
597 | ||
3a40aaa0 UW |
598 | arch_size = bfd_get_arch_size (abfd); |
599 | if (arch_size == -1) | |
0763ab81 | 600 | return 0; |
3a40aaa0 UW |
601 | |
602 | /* Find the start address of the .dynamic section. */ | |
603 | sect = bfd_get_section_by_name (abfd, ".dynamic"); | |
604 | if (sect == NULL) | |
605 | return 0; | |
61f0d762 JK |
606 | |
607 | for (target_section = current_target_sections->sections; | |
608 | target_section < current_target_sections->sections_end; | |
609 | target_section++) | |
610 | if (sect == target_section->the_bfd_section) | |
611 | break; | |
b381ea14 JK |
612 | if (target_section < current_target_sections->sections_end) |
613 | dyn_addr = target_section->addr; | |
614 | else | |
615 | { | |
616 | /* ABFD may come from OBJFILE acting only as a symbol file without being | |
617 | loaded into the target (see add_symbol_file_command). This case is | |
618 | such fallback to the file VMA address without the possibility of | |
619 | having the section relocated to its actual in-memory address. */ | |
620 | ||
621 | dyn_addr = bfd_section_vma (abfd, sect); | |
622 | } | |
3a40aaa0 | 623 | |
65728c26 DJ |
624 | /* Read in .dynamic from the BFD. We will get the actual value |
625 | from memory later. */ | |
3a40aaa0 | 626 | sect_size = bfd_section_size (abfd, sect); |
224c3ddb | 627 | buf = bufstart = (gdb_byte *) alloca (sect_size); |
65728c26 DJ |
628 | if (!bfd_get_section_contents (abfd, sect, |
629 | buf, 0, sect_size)) | |
630 | return 0; | |
3a40aaa0 UW |
631 | |
632 | /* Iterate over BUF and scan for DYNTAG. If found, set PTR and return. */ | |
633 | step = (arch_size == 32) ? sizeof (Elf32_External_Dyn) | |
634 | : sizeof (Elf64_External_Dyn); | |
635 | for (bufend = buf + sect_size; | |
636 | buf < bufend; | |
637 | buf += step) | |
638 | { | |
639 | if (arch_size == 32) | |
640 | { | |
641 | x_dynp_32 = (Elf32_External_Dyn *) buf; | |
b6d7a4bf | 642 | current_dyntag = bfd_h_get_32 (abfd, (bfd_byte *) x_dynp_32->d_tag); |
3a40aaa0 UW |
643 | dyn_ptr = bfd_h_get_32 (abfd, (bfd_byte *) x_dynp_32->d_un.d_ptr); |
644 | } | |
65728c26 | 645 | else |
3a40aaa0 UW |
646 | { |
647 | x_dynp_64 = (Elf64_External_Dyn *) buf; | |
b6d7a4bf | 648 | current_dyntag = bfd_h_get_64 (abfd, (bfd_byte *) x_dynp_64->d_tag); |
3a40aaa0 UW |
649 | dyn_ptr = bfd_h_get_64 (abfd, (bfd_byte *) x_dynp_64->d_un.d_ptr); |
650 | } | |
b6d7a4bf | 651 | if (current_dyntag == DT_NULL) |
3a40aaa0 | 652 | return 0; |
b6d7a4bf | 653 | if (current_dyntag == desired_dyntag) |
3a40aaa0 | 654 | { |
65728c26 DJ |
655 | /* If requested, try to read the runtime value of this .dynamic |
656 | entry. */ | |
3a40aaa0 | 657 | if (ptr) |
65728c26 | 658 | { |
b6da22b0 | 659 | struct type *ptr_type; |
65728c26 | 660 | gdb_byte ptr_buf[8]; |
a738da3a | 661 | CORE_ADDR ptr_addr_1; |
65728c26 | 662 | |
f5656ead | 663 | ptr_type = builtin_type (target_gdbarch ())->builtin_data_ptr; |
a738da3a MF |
664 | ptr_addr_1 = dyn_addr + (buf - bufstart) + arch_size / 8; |
665 | if (target_read_memory (ptr_addr_1, ptr_buf, arch_size / 8) == 0) | |
b6da22b0 | 666 | dyn_ptr = extract_typed_address (ptr_buf, ptr_type); |
65728c26 | 667 | *ptr = dyn_ptr; |
a738da3a MF |
668 | if (ptr_addr) |
669 | *ptr_addr = dyn_addr + (buf - bufstart); | |
65728c26 DJ |
670 | } |
671 | return 1; | |
3a40aaa0 UW |
672 | } |
673 | } | |
674 | ||
675 | return 0; | |
676 | } | |
677 | ||
b6d7a4bf SM |
678 | /* Scan for DESIRED_DYNTAG in .dynamic section of the target's main executable, |
679 | found by consulting the OS auxillary vector. If DESIRED_DYNTAG is found, 1 | |
680 | is returned and the corresponding PTR is set. */ | |
97ec2c2f UW |
681 | |
682 | static int | |
a738da3a MF |
683 | scan_dyntag_auxv (const int desired_dyntag, CORE_ADDR *ptr, |
684 | CORE_ADDR *ptr_addr) | |
97ec2c2f | 685 | { |
f5656ead | 686 | enum bfd_endian byte_order = gdbarch_byte_order (target_gdbarch ()); |
17658d46 | 687 | int arch_size, step; |
b6d7a4bf | 688 | long current_dyntag; |
97ec2c2f | 689 | CORE_ADDR dyn_ptr; |
a738da3a | 690 | CORE_ADDR base_addr; |
97ec2c2f UW |
691 | |
692 | /* Read in .dynamic section. */ | |
17658d46 SM |
693 | gdb::optional<gdb::byte_vector> ph_data |
694 | = read_program_header (PT_DYNAMIC, &arch_size, &base_addr); | |
695 | if (!ph_data) | |
97ec2c2f UW |
696 | return 0; |
697 | ||
698 | /* Iterate over BUF and scan for DYNTAG. If found, set PTR and return. */ | |
699 | step = (arch_size == 32) ? sizeof (Elf32_External_Dyn) | |
700 | : sizeof (Elf64_External_Dyn); | |
17658d46 SM |
701 | for (gdb_byte *buf = ph_data->data (), *bufend = buf + ph_data->size (); |
702 | buf < bufend; buf += step) | |
97ec2c2f UW |
703 | { |
704 | if (arch_size == 32) | |
705 | { | |
706 | Elf32_External_Dyn *dynp = (Elf32_External_Dyn *) buf; | |
433759f7 | 707 | |
b6d7a4bf | 708 | current_dyntag = extract_unsigned_integer ((gdb_byte *) dynp->d_tag, |
e17a4113 UW |
709 | 4, byte_order); |
710 | dyn_ptr = extract_unsigned_integer ((gdb_byte *) dynp->d_un.d_ptr, | |
711 | 4, byte_order); | |
97ec2c2f UW |
712 | } |
713 | else | |
714 | { | |
715 | Elf64_External_Dyn *dynp = (Elf64_External_Dyn *) buf; | |
433759f7 | 716 | |
b6d7a4bf | 717 | current_dyntag = extract_unsigned_integer ((gdb_byte *) dynp->d_tag, |
e17a4113 UW |
718 | 8, byte_order); |
719 | dyn_ptr = extract_unsigned_integer ((gdb_byte *) dynp->d_un.d_ptr, | |
720 | 8, byte_order); | |
97ec2c2f | 721 | } |
b6d7a4bf | 722 | if (current_dyntag == DT_NULL) |
97ec2c2f UW |
723 | break; |
724 | ||
b6d7a4bf | 725 | if (current_dyntag == desired_dyntag) |
97ec2c2f UW |
726 | { |
727 | if (ptr) | |
728 | *ptr = dyn_ptr; | |
729 | ||
a738da3a | 730 | if (ptr_addr) |
17658d46 | 731 | *ptr_addr = base_addr + buf - ph_data->data (); |
a738da3a | 732 | |
97ec2c2f UW |
733 | return 1; |
734 | } | |
735 | } | |
736 | ||
97ec2c2f UW |
737 | return 0; |
738 | } | |
739 | ||
7f86f058 PA |
740 | /* Locate the base address of dynamic linker structs for SVR4 elf |
741 | targets. | |
13437d4b KB |
742 | |
743 | For SVR4 elf targets the address of the dynamic linker's runtime | |
744 | structure is contained within the dynamic info section in the | |
745 | executable file. The dynamic section is also mapped into the | |
746 | inferior address space. Because the runtime loader fills in the | |
747 | real address before starting the inferior, we have to read in the | |
748 | dynamic info section from the inferior address space. | |
749 | If there are any errors while trying to find the address, we | |
7f86f058 | 750 | silently return 0, otherwise the found address is returned. */ |
13437d4b KB |
751 | |
752 | static CORE_ADDR | |
753 | elf_locate_base (void) | |
754 | { | |
3b7344d5 | 755 | struct bound_minimal_symbol msymbol; |
a738da3a | 756 | CORE_ADDR dyn_ptr, dyn_ptr_addr; |
13437d4b | 757 | |
65728c26 DJ |
758 | /* Look for DT_MIPS_RLD_MAP first. MIPS executables use this |
759 | instead of DT_DEBUG, although they sometimes contain an unused | |
760 | DT_DEBUG. */ | |
a738da3a MF |
761 | if (scan_dyntag (DT_MIPS_RLD_MAP, exec_bfd, &dyn_ptr, NULL) |
762 | || scan_dyntag_auxv (DT_MIPS_RLD_MAP, &dyn_ptr, NULL)) | |
3a40aaa0 | 763 | { |
f5656ead | 764 | struct type *ptr_type = builtin_type (target_gdbarch ())->builtin_data_ptr; |
3a40aaa0 | 765 | gdb_byte *pbuf; |
b6da22b0 | 766 | int pbuf_size = TYPE_LENGTH (ptr_type); |
433759f7 | 767 | |
224c3ddb | 768 | pbuf = (gdb_byte *) alloca (pbuf_size); |
3a40aaa0 UW |
769 | /* DT_MIPS_RLD_MAP contains a pointer to the address |
770 | of the dynamic link structure. */ | |
771 | if (target_read_memory (dyn_ptr, pbuf, pbuf_size)) | |
e499d0f1 | 772 | return 0; |
b6da22b0 | 773 | return extract_typed_address (pbuf, ptr_type); |
e499d0f1 DJ |
774 | } |
775 | ||
a738da3a MF |
776 | /* Then check DT_MIPS_RLD_MAP_REL. MIPS executables now use this form |
777 | because of needing to support PIE. DT_MIPS_RLD_MAP will also exist | |
778 | in non-PIE. */ | |
779 | if (scan_dyntag (DT_MIPS_RLD_MAP_REL, exec_bfd, &dyn_ptr, &dyn_ptr_addr) | |
780 | || scan_dyntag_auxv (DT_MIPS_RLD_MAP_REL, &dyn_ptr, &dyn_ptr_addr)) | |
781 | { | |
782 | struct type *ptr_type = builtin_type (target_gdbarch ())->builtin_data_ptr; | |
783 | gdb_byte *pbuf; | |
784 | int pbuf_size = TYPE_LENGTH (ptr_type); | |
785 | ||
224c3ddb | 786 | pbuf = (gdb_byte *) alloca (pbuf_size); |
a738da3a MF |
787 | /* DT_MIPS_RLD_MAP_REL contains an offset from the address of the |
788 | DT slot to the address of the dynamic link structure. */ | |
789 | if (target_read_memory (dyn_ptr + dyn_ptr_addr, pbuf, pbuf_size)) | |
790 | return 0; | |
791 | return extract_typed_address (pbuf, ptr_type); | |
792 | } | |
793 | ||
65728c26 | 794 | /* Find DT_DEBUG. */ |
a738da3a MF |
795 | if (scan_dyntag (DT_DEBUG, exec_bfd, &dyn_ptr, NULL) |
796 | || scan_dyntag_auxv (DT_DEBUG, &dyn_ptr, NULL)) | |
65728c26 DJ |
797 | return dyn_ptr; |
798 | ||
3a40aaa0 UW |
799 | /* This may be a static executable. Look for the symbol |
800 | conventionally named _r_debug, as a last resort. */ | |
801 | msymbol = lookup_minimal_symbol ("_r_debug", NULL, symfile_objfile); | |
3b7344d5 | 802 | if (msymbol.minsym != NULL) |
77e371c0 | 803 | return BMSYMBOL_VALUE_ADDRESS (msymbol); |
13437d4b KB |
804 | |
805 | /* DT_DEBUG entry not found. */ | |
806 | return 0; | |
807 | } | |
808 | ||
7f86f058 | 809 | /* Locate the base address of dynamic linker structs. |
13437d4b KB |
810 | |
811 | For both the SunOS and SVR4 shared library implementations, if the | |
812 | inferior executable has been linked dynamically, there is a single | |
813 | address somewhere in the inferior's data space which is the key to | |
814 | locating all of the dynamic linker's runtime structures. This | |
815 | address is the value of the debug base symbol. The job of this | |
816 | function is to find and return that address, or to return 0 if there | |
817 | is no such address (the executable is statically linked for example). | |
818 | ||
819 | For SunOS, the job is almost trivial, since the dynamic linker and | |
820 | all of it's structures are statically linked to the executable at | |
821 | link time. Thus the symbol for the address we are looking for has | |
822 | already been added to the minimal symbol table for the executable's | |
823 | objfile at the time the symbol file's symbols were read, and all we | |
824 | have to do is look it up there. Note that we explicitly do NOT want | |
825 | to find the copies in the shared library. | |
826 | ||
827 | The SVR4 version is a bit more complicated because the address | |
828 | is contained somewhere in the dynamic info section. We have to go | |
829 | to a lot more work to discover the address of the debug base symbol. | |
830 | Because of this complexity, we cache the value we find and return that | |
831 | value on subsequent invocations. Note there is no copy in the | |
7f86f058 | 832 | executable symbol tables. */ |
13437d4b KB |
833 | |
834 | static CORE_ADDR | |
1a816a87 | 835 | locate_base (struct svr4_info *info) |
13437d4b | 836 | { |
13437d4b KB |
837 | /* Check to see if we have a currently valid address, and if so, avoid |
838 | doing all this work again and just return the cached address. If | |
839 | we have no cached address, try to locate it in the dynamic info | |
d5a921c9 KB |
840 | section for ELF executables. There's no point in doing any of this |
841 | though if we don't have some link map offsets to work with. */ | |
13437d4b | 842 | |
1a816a87 | 843 | if (info->debug_base == 0 && svr4_have_link_map_offsets ()) |
0763ab81 | 844 | info->debug_base = elf_locate_base (); |
1a816a87 | 845 | return info->debug_base; |
13437d4b KB |
846 | } |
847 | ||
e4cd0d6a | 848 | /* Find the first element in the inferior's dynamic link map, and |
6f992fbf JB |
849 | return its address in the inferior. Return zero if the address |
850 | could not be determined. | |
13437d4b | 851 | |
e4cd0d6a MK |
852 | FIXME: Perhaps we should validate the info somehow, perhaps by |
853 | checking r_version for a known version number, or r_state for | |
854 | RT_CONSISTENT. */ | |
13437d4b KB |
855 | |
856 | static CORE_ADDR | |
1a816a87 | 857 | solib_svr4_r_map (struct svr4_info *info) |
13437d4b | 858 | { |
4b188b9f | 859 | struct link_map_offsets *lmo = svr4_fetch_link_map_offsets (); |
f5656ead | 860 | struct type *ptr_type = builtin_type (target_gdbarch ())->builtin_data_ptr; |
08597104 | 861 | CORE_ADDR addr = 0; |
13437d4b | 862 | |
a70b8144 | 863 | try |
08597104 JB |
864 | { |
865 | addr = read_memory_typed_address (info->debug_base + lmo->r_map_offset, | |
866 | ptr_type); | |
867 | } | |
230d2906 | 868 | catch (const gdb_exception_error &ex) |
492d29ea PA |
869 | { |
870 | exception_print (gdb_stderr, ex); | |
871 | } | |
492d29ea | 872 | |
08597104 | 873 | return addr; |
e4cd0d6a | 874 | } |
13437d4b | 875 | |
7cd25cfc DJ |
876 | /* Find r_brk from the inferior's debug base. */ |
877 | ||
878 | static CORE_ADDR | |
1a816a87 | 879 | solib_svr4_r_brk (struct svr4_info *info) |
7cd25cfc DJ |
880 | { |
881 | struct link_map_offsets *lmo = svr4_fetch_link_map_offsets (); | |
f5656ead | 882 | struct type *ptr_type = builtin_type (target_gdbarch ())->builtin_data_ptr; |
7cd25cfc | 883 | |
1a816a87 PA |
884 | return read_memory_typed_address (info->debug_base + lmo->r_brk_offset, |
885 | ptr_type); | |
7cd25cfc DJ |
886 | } |
887 | ||
e4cd0d6a MK |
888 | /* Find the link map for the dynamic linker (if it is not in the |
889 | normal list of loaded shared objects). */ | |
13437d4b | 890 | |
e4cd0d6a | 891 | static CORE_ADDR |
1a816a87 | 892 | solib_svr4_r_ldsomap (struct svr4_info *info) |
e4cd0d6a MK |
893 | { |
894 | struct link_map_offsets *lmo = svr4_fetch_link_map_offsets (); | |
f5656ead TT |
895 | struct type *ptr_type = builtin_type (target_gdbarch ())->builtin_data_ptr; |
896 | enum bfd_endian byte_order = gdbarch_byte_order (target_gdbarch ()); | |
416f679e SDJ |
897 | ULONGEST version = 0; |
898 | ||
a70b8144 | 899 | try |
416f679e SDJ |
900 | { |
901 | /* Check version, and return zero if `struct r_debug' doesn't have | |
902 | the r_ldsomap member. */ | |
903 | version | |
904 | = read_memory_unsigned_integer (info->debug_base + lmo->r_version_offset, | |
905 | lmo->r_version_size, byte_order); | |
906 | } | |
230d2906 | 907 | catch (const gdb_exception_error &ex) |
416f679e SDJ |
908 | { |
909 | exception_print (gdb_stderr, ex); | |
910 | } | |
13437d4b | 911 | |
e4cd0d6a MK |
912 | if (version < 2 || lmo->r_ldsomap_offset == -1) |
913 | return 0; | |
13437d4b | 914 | |
1a816a87 | 915 | return read_memory_typed_address (info->debug_base + lmo->r_ldsomap_offset, |
b6da22b0 | 916 | ptr_type); |
13437d4b KB |
917 | } |
918 | ||
de18c1d8 JM |
919 | /* On Solaris systems with some versions of the dynamic linker, |
920 | ld.so's l_name pointer points to the SONAME in the string table | |
921 | rather than into writable memory. So that GDB can find shared | |
922 | libraries when loading a core file generated by gcore, ensure that | |
923 | memory areas containing the l_name string are saved in the core | |
924 | file. */ | |
925 | ||
926 | static int | |
927 | svr4_keep_data_in_core (CORE_ADDR vaddr, unsigned long size) | |
928 | { | |
929 | struct svr4_info *info; | |
930 | CORE_ADDR ldsomap; | |
74de0234 | 931 | CORE_ADDR name_lm; |
de18c1d8 | 932 | |
d70cc3ba | 933 | info = get_svr4_info (current_program_space); |
de18c1d8 JM |
934 | |
935 | info->debug_base = 0; | |
936 | locate_base (info); | |
937 | if (!info->debug_base) | |
938 | return 0; | |
939 | ||
940 | ldsomap = solib_svr4_r_ldsomap (info); | |
941 | if (!ldsomap) | |
942 | return 0; | |
943 | ||
a7961323 | 944 | std::unique_ptr<lm_info_svr4> li = lm_info_read (ldsomap); |
d0e449a1 | 945 | name_lm = li != NULL ? li->l_name : 0; |
de18c1d8 | 946 | |
74de0234 | 947 | return (name_lm >= vaddr && name_lm < vaddr + size); |
de18c1d8 JM |
948 | } |
949 | ||
bf469271 | 950 | /* See solist.h. */ |
13437d4b KB |
951 | |
952 | static int | |
bf469271 | 953 | open_symbol_file_object (int from_tty) |
13437d4b KB |
954 | { |
955 | CORE_ADDR lm, l_name; | |
e83e4e24 | 956 | gdb::unique_xmalloc_ptr<char> filename; |
13437d4b | 957 | int errcode; |
4b188b9f | 958 | struct link_map_offsets *lmo = svr4_fetch_link_map_offsets (); |
f5656ead | 959 | struct type *ptr_type = builtin_type (target_gdbarch ())->builtin_data_ptr; |
b6da22b0 | 960 | int l_name_size = TYPE_LENGTH (ptr_type); |
a7961323 | 961 | gdb::byte_vector l_name_buf (l_name_size); |
d70cc3ba | 962 | struct svr4_info *info = get_svr4_info (current_program_space); |
ecf45d2c SL |
963 | symfile_add_flags add_flags = 0; |
964 | ||
965 | if (from_tty) | |
966 | add_flags |= SYMFILE_VERBOSE; | |
13437d4b KB |
967 | |
968 | if (symfile_objfile) | |
9e2f0ad4 | 969 | if (!query (_("Attempt to reload symbols from process? "))) |
a7961323 | 970 | return 0; |
13437d4b | 971 | |
7cd25cfc | 972 | /* Always locate the debug struct, in case it has moved. */ |
1a816a87 PA |
973 | info->debug_base = 0; |
974 | if (locate_base (info) == 0) | |
a7961323 | 975 | return 0; /* failed somehow... */ |
13437d4b KB |
976 | |
977 | /* First link map member should be the executable. */ | |
1a816a87 | 978 | lm = solib_svr4_r_map (info); |
e4cd0d6a | 979 | if (lm == 0) |
a7961323 | 980 | return 0; /* failed somehow... */ |
13437d4b KB |
981 | |
982 | /* Read address of name from target memory to GDB. */ | |
a7961323 | 983 | read_memory (lm + lmo->l_name_offset, l_name_buf.data (), l_name_size); |
13437d4b | 984 | |
cfaefc65 | 985 | /* Convert the address to host format. */ |
a7961323 | 986 | l_name = extract_typed_address (l_name_buf.data (), ptr_type); |
13437d4b | 987 | |
13437d4b | 988 | if (l_name == 0) |
a7961323 | 989 | return 0; /* No filename. */ |
13437d4b KB |
990 | |
991 | /* Now fetch the filename from target memory. */ | |
992 | target_read_string (l_name, &filename, SO_NAME_MAX_PATH_SIZE - 1, &errcode); | |
993 | ||
994 | if (errcode) | |
995 | { | |
8a3fe4f8 | 996 | warning (_("failed to read exec filename from attached file: %s"), |
13437d4b KB |
997 | safe_strerror (errcode)); |
998 | return 0; | |
999 | } | |
1000 | ||
13437d4b | 1001 | /* Have a pathname: read the symbol file. */ |
e83e4e24 | 1002 | symbol_file_add_main (filename.get (), add_flags); |
13437d4b KB |
1003 | |
1004 | return 1; | |
1005 | } | |
13437d4b | 1006 | |
2268b414 JK |
1007 | /* Data exchange structure for the XML parser as returned by |
1008 | svr4_current_sos_via_xfer_libraries. */ | |
1009 | ||
1010 | struct svr4_library_list | |
1011 | { | |
1012 | struct so_list *head, **tailp; | |
1013 | ||
1014 | /* Inferior address of struct link_map used for the main executable. It is | |
1015 | NULL if not known. */ | |
1016 | CORE_ADDR main_lm; | |
1017 | }; | |
1018 | ||
7905fc35 PA |
1019 | /* This module's 'free_objfile' observer. */ |
1020 | ||
1021 | static void | |
1022 | svr4_free_objfile_observer (struct objfile *objfile) | |
1023 | { | |
1024 | probes_table_remove_objfile_probes (objfile); | |
1025 | } | |
1026 | ||
93f2a35e JK |
1027 | /* Implementation for target_so_ops.free_so. */ |
1028 | ||
1029 | static void | |
1030 | svr4_free_so (struct so_list *so) | |
1031 | { | |
76e75227 SM |
1032 | lm_info_svr4 *li = (lm_info_svr4 *) so->lm_info; |
1033 | ||
1034 | delete li; | |
93f2a35e JK |
1035 | } |
1036 | ||
0892cb63 DE |
1037 | /* Implement target_so_ops.clear_so. */ |
1038 | ||
1039 | static void | |
1040 | svr4_clear_so (struct so_list *so) | |
1041 | { | |
d0e449a1 SM |
1042 | lm_info_svr4 *li = (lm_info_svr4 *) so->lm_info; |
1043 | ||
1044 | if (li != NULL) | |
1045 | li->l_addr_p = 0; | |
0892cb63 DE |
1046 | } |
1047 | ||
93f2a35e JK |
1048 | /* Free so_list built so far (called via cleanup). */ |
1049 | ||
1050 | static void | |
1051 | svr4_free_library_list (void *p_list) | |
1052 | { | |
1053 | struct so_list *list = *(struct so_list **) p_list; | |
1054 | ||
1055 | while (list != NULL) | |
1056 | { | |
1057 | struct so_list *next = list->next; | |
1058 | ||
3756ef7e | 1059 | free_so (list); |
93f2a35e JK |
1060 | list = next; |
1061 | } | |
1062 | } | |
1063 | ||
f9e14852 GB |
1064 | /* Copy library list. */ |
1065 | ||
1066 | static struct so_list * | |
1067 | svr4_copy_library_list (struct so_list *src) | |
1068 | { | |
1069 | struct so_list *dst = NULL; | |
1070 | struct so_list **link = &dst; | |
1071 | ||
1072 | while (src != NULL) | |
1073 | { | |
fe978cb0 | 1074 | struct so_list *newobj; |
f9e14852 | 1075 | |
8d749320 | 1076 | newobj = XNEW (struct so_list); |
fe978cb0 | 1077 | memcpy (newobj, src, sizeof (struct so_list)); |
f9e14852 | 1078 | |
76e75227 SM |
1079 | lm_info_svr4 *src_li = (lm_info_svr4 *) src->lm_info; |
1080 | newobj->lm_info = new lm_info_svr4 (*src_li); | |
f9e14852 | 1081 | |
fe978cb0 PA |
1082 | newobj->next = NULL; |
1083 | *link = newobj; | |
1084 | link = &newobj->next; | |
f9e14852 GB |
1085 | |
1086 | src = src->next; | |
1087 | } | |
1088 | ||
1089 | return dst; | |
1090 | } | |
1091 | ||
2268b414 JK |
1092 | #ifdef HAVE_LIBEXPAT |
1093 | ||
1094 | #include "xml-support.h" | |
1095 | ||
1096 | /* Handle the start of a <library> element. Note: new elements are added | |
1097 | at the tail of the list, keeping the list in order. */ | |
1098 | ||
1099 | static void | |
1100 | library_list_start_library (struct gdb_xml_parser *parser, | |
1101 | const struct gdb_xml_element *element, | |
4d0fdd9b SM |
1102 | void *user_data, |
1103 | std::vector<gdb_xml_value> &attributes) | |
2268b414 | 1104 | { |
19ba03f4 SM |
1105 | struct svr4_library_list *list = (struct svr4_library_list *) user_data; |
1106 | const char *name | |
4d0fdd9b | 1107 | = (const char *) xml_find_attribute (attributes, "name")->value.get (); |
19ba03f4 | 1108 | ULONGEST *lmp |
4d0fdd9b | 1109 | = (ULONGEST *) xml_find_attribute (attributes, "lm")->value.get (); |
19ba03f4 | 1110 | ULONGEST *l_addrp |
4d0fdd9b | 1111 | = (ULONGEST *) xml_find_attribute (attributes, "l_addr")->value.get (); |
19ba03f4 | 1112 | ULONGEST *l_ldp |
4d0fdd9b | 1113 | = (ULONGEST *) xml_find_attribute (attributes, "l_ld")->value.get (); |
2268b414 JK |
1114 | struct so_list *new_elem; |
1115 | ||
41bf6aca | 1116 | new_elem = XCNEW (struct so_list); |
76e75227 | 1117 | lm_info_svr4 *li = new lm_info_svr4; |
d0e449a1 SM |
1118 | new_elem->lm_info = li; |
1119 | li->lm_addr = *lmp; | |
1120 | li->l_addr_inferior = *l_addrp; | |
1121 | li->l_ld = *l_ldp; | |
2268b414 JK |
1122 | |
1123 | strncpy (new_elem->so_name, name, sizeof (new_elem->so_name) - 1); | |
1124 | new_elem->so_name[sizeof (new_elem->so_name) - 1] = 0; | |
1125 | strcpy (new_elem->so_original_name, new_elem->so_name); | |
1126 | ||
1127 | *list->tailp = new_elem; | |
1128 | list->tailp = &new_elem->next; | |
1129 | } | |
1130 | ||
1131 | /* Handle the start of a <library-list-svr4> element. */ | |
1132 | ||
1133 | static void | |
1134 | svr4_library_list_start_list (struct gdb_xml_parser *parser, | |
1135 | const struct gdb_xml_element *element, | |
4d0fdd9b SM |
1136 | void *user_data, |
1137 | std::vector<gdb_xml_value> &attributes) | |
2268b414 | 1138 | { |
19ba03f4 SM |
1139 | struct svr4_library_list *list = (struct svr4_library_list *) user_data; |
1140 | const char *version | |
4d0fdd9b | 1141 | = (const char *) xml_find_attribute (attributes, "version")->value.get (); |
2268b414 JK |
1142 | struct gdb_xml_value *main_lm = xml_find_attribute (attributes, "main-lm"); |
1143 | ||
1144 | if (strcmp (version, "1.0") != 0) | |
1145 | gdb_xml_error (parser, | |
1146 | _("SVR4 Library list has unsupported version \"%s\""), | |
1147 | version); | |
1148 | ||
1149 | if (main_lm) | |
4d0fdd9b | 1150 | list->main_lm = *(ULONGEST *) main_lm->value.get (); |
2268b414 JK |
1151 | } |
1152 | ||
1153 | /* The allowed elements and attributes for an XML library list. | |
1154 | The root element is a <library-list>. */ | |
1155 | ||
1156 | static const struct gdb_xml_attribute svr4_library_attributes[] = | |
1157 | { | |
1158 | { "name", GDB_XML_AF_NONE, NULL, NULL }, | |
1159 | { "lm", GDB_XML_AF_NONE, gdb_xml_parse_attr_ulongest, NULL }, | |
1160 | { "l_addr", GDB_XML_AF_NONE, gdb_xml_parse_attr_ulongest, NULL }, | |
1161 | { "l_ld", GDB_XML_AF_NONE, gdb_xml_parse_attr_ulongest, NULL }, | |
1162 | { NULL, GDB_XML_AF_NONE, NULL, NULL } | |
1163 | }; | |
1164 | ||
1165 | static const struct gdb_xml_element svr4_library_list_children[] = | |
1166 | { | |
1167 | { | |
1168 | "library", svr4_library_attributes, NULL, | |
1169 | GDB_XML_EF_REPEATABLE | GDB_XML_EF_OPTIONAL, | |
1170 | library_list_start_library, NULL | |
1171 | }, | |
1172 | { NULL, NULL, NULL, GDB_XML_EF_NONE, NULL, NULL } | |
1173 | }; | |
1174 | ||
1175 | static const struct gdb_xml_attribute svr4_library_list_attributes[] = | |
1176 | { | |
1177 | { "version", GDB_XML_AF_NONE, NULL, NULL }, | |
1178 | { "main-lm", GDB_XML_AF_OPTIONAL, gdb_xml_parse_attr_ulongest, NULL }, | |
1179 | { NULL, GDB_XML_AF_NONE, NULL, NULL } | |
1180 | }; | |
1181 | ||
1182 | static const struct gdb_xml_element svr4_library_list_elements[] = | |
1183 | { | |
1184 | { "library-list-svr4", svr4_library_list_attributes, svr4_library_list_children, | |
1185 | GDB_XML_EF_NONE, svr4_library_list_start_list, NULL }, | |
1186 | { NULL, NULL, NULL, GDB_XML_EF_NONE, NULL, NULL } | |
1187 | }; | |
1188 | ||
2268b414 JK |
1189 | /* Parse qXfer:libraries:read packet into *SO_LIST_RETURN. Return 1 if |
1190 | ||
1191 | Return 0 if packet not supported, *SO_LIST_RETURN is not modified in such | |
1192 | case. Return 1 if *SO_LIST_RETURN contains the library list, it may be | |
1193 | empty, caller is responsible for freeing all its entries. */ | |
1194 | ||
1195 | static int | |
1196 | svr4_parse_libraries (const char *document, struct svr4_library_list *list) | |
1197 | { | |
2b6ff1c0 TT |
1198 | auto cleanup = make_scope_exit ([&] () |
1199 | { | |
1200 | svr4_free_library_list (&list->head); | |
1201 | }); | |
2268b414 JK |
1202 | |
1203 | memset (list, 0, sizeof (*list)); | |
1204 | list->tailp = &list->head; | |
2eca4a8d | 1205 | if (gdb_xml_parse_quick (_("target library list"), "library-list-svr4.dtd", |
2268b414 JK |
1206 | svr4_library_list_elements, document, list) == 0) |
1207 | { | |
1208 | /* Parsed successfully, keep the result. */ | |
2b6ff1c0 | 1209 | cleanup.release (); |
2268b414 JK |
1210 | return 1; |
1211 | } | |
1212 | ||
2268b414 JK |
1213 | return 0; |
1214 | } | |
1215 | ||
f9e14852 | 1216 | /* Attempt to get so_list from target via qXfer:libraries-svr4:read packet. |
2268b414 JK |
1217 | |
1218 | Return 0 if packet not supported, *SO_LIST_RETURN is not modified in such | |
1219 | case. Return 1 if *SO_LIST_RETURN contains the library list, it may be | |
f9e14852 GB |
1220 | empty, caller is responsible for freeing all its entries. |
1221 | ||
1222 | Note that ANNEX must be NULL if the remote does not explicitly allow | |
1223 | qXfer:libraries-svr4:read packets with non-empty annexes. Support for | |
1224 | this can be checked using target_augmented_libraries_svr4_read (). */ | |
2268b414 JK |
1225 | |
1226 | static int | |
f9e14852 GB |
1227 | svr4_current_sos_via_xfer_libraries (struct svr4_library_list *list, |
1228 | const char *annex) | |
2268b414 | 1229 | { |
f9e14852 GB |
1230 | gdb_assert (annex == NULL || target_augmented_libraries_svr4_read ()); |
1231 | ||
2268b414 | 1232 | /* Fetch the list of shared libraries. */ |
9018be22 | 1233 | gdb::optional<gdb::char_vector> svr4_library_document |
8b88a78e | 1234 | = target_read_stralloc (current_top_target (), TARGET_OBJECT_LIBRARIES_SVR4, |
b7b030ad | 1235 | annex); |
9018be22 | 1236 | if (!svr4_library_document) |
2268b414 JK |
1237 | return 0; |
1238 | ||
9018be22 | 1239 | return svr4_parse_libraries (svr4_library_document->data (), list); |
2268b414 JK |
1240 | } |
1241 | ||
1242 | #else | |
1243 | ||
1244 | static int | |
f9e14852 GB |
1245 | svr4_current_sos_via_xfer_libraries (struct svr4_library_list *list, |
1246 | const char *annex) | |
2268b414 JK |
1247 | { |
1248 | return 0; | |
1249 | } | |
1250 | ||
1251 | #endif | |
1252 | ||
34439770 DJ |
1253 | /* If no shared library information is available from the dynamic |
1254 | linker, build a fallback list from other sources. */ | |
1255 | ||
1256 | static struct so_list * | |
d70cc3ba | 1257 | svr4_default_sos (svr4_info *info) |
34439770 | 1258 | { |
fe978cb0 | 1259 | struct so_list *newobj; |
1a816a87 | 1260 | |
8e5c319d JK |
1261 | if (!info->debug_loader_offset_p) |
1262 | return NULL; | |
34439770 | 1263 | |
fe978cb0 | 1264 | newobj = XCNEW (struct so_list); |
76e75227 | 1265 | lm_info_svr4 *li = new lm_info_svr4; |
d0e449a1 | 1266 | newobj->lm_info = li; |
34439770 | 1267 | |
3957565a | 1268 | /* Nothing will ever check the other fields if we set l_addr_p. */ |
d0e449a1 SM |
1269 | li->l_addr = info->debug_loader_offset; |
1270 | li->l_addr_p = 1; | |
34439770 | 1271 | |
fe978cb0 PA |
1272 | strncpy (newobj->so_name, info->debug_loader_name, SO_NAME_MAX_PATH_SIZE - 1); |
1273 | newobj->so_name[SO_NAME_MAX_PATH_SIZE - 1] = '\0'; | |
1274 | strcpy (newobj->so_original_name, newobj->so_name); | |
34439770 | 1275 | |
fe978cb0 | 1276 | return newobj; |
34439770 DJ |
1277 | } |
1278 | ||
f9e14852 GB |
1279 | /* Read the whole inferior libraries chain starting at address LM. |
1280 | Expect the first entry in the chain's previous entry to be PREV_LM. | |
1281 | Add the entries to the tail referenced by LINK_PTR_PTR. Ignore the | |
1282 | first entry if IGNORE_FIRST and set global MAIN_LM_ADDR according | |
1283 | to it. Returns nonzero upon success. If zero is returned the | |
1284 | entries stored to LINK_PTR_PTR are still valid although they may | |
1285 | represent only part of the inferior library list. */ | |
13437d4b | 1286 | |
f9e14852 | 1287 | static int |
d70cc3ba | 1288 | svr4_read_so_list (svr4_info *info, CORE_ADDR lm, CORE_ADDR prev_lm, |
f9e14852 | 1289 | struct so_list ***link_ptr_ptr, int ignore_first) |
13437d4b | 1290 | { |
c725e7b6 | 1291 | CORE_ADDR first_l_name = 0; |
f9e14852 | 1292 | CORE_ADDR next_lm; |
13437d4b | 1293 | |
cb08cc53 | 1294 | for (; lm != 0; prev_lm = lm, lm = next_lm) |
13437d4b | 1295 | { |
cb08cc53 | 1296 | int errcode; |
e83e4e24 | 1297 | gdb::unique_xmalloc_ptr<char> buffer; |
13437d4b | 1298 | |
b3bc8453 | 1299 | so_list_up newobj (XCNEW (struct so_list)); |
13437d4b | 1300 | |
a7961323 | 1301 | lm_info_svr4 *li = lm_info_read (lm).release (); |
d0e449a1 SM |
1302 | newobj->lm_info = li; |
1303 | if (li == NULL) | |
b3bc8453 | 1304 | return 0; |
13437d4b | 1305 | |
d0e449a1 | 1306 | next_lm = li->l_next; |
492928e4 | 1307 | |
d0e449a1 | 1308 | if (li->l_prev != prev_lm) |
492928e4 | 1309 | { |
2268b414 | 1310 | warning (_("Corrupted shared library list: %s != %s"), |
f5656ead | 1311 | paddress (target_gdbarch (), prev_lm), |
d0e449a1 | 1312 | paddress (target_gdbarch (), li->l_prev)); |
f9e14852 | 1313 | return 0; |
492928e4 | 1314 | } |
13437d4b KB |
1315 | |
1316 | /* For SVR4 versions, the first entry in the link map is for the | |
1317 | inferior executable, so we must ignore it. For some versions of | |
1318 | SVR4, it has no name. For others (Solaris 2.3 for example), it | |
1319 | does have a name, so we can no longer use a missing name to | |
c378eb4e | 1320 | decide when to ignore it. */ |
d0e449a1 | 1321 | if (ignore_first && li->l_prev == 0) |
93a57060 | 1322 | { |
d0e449a1 SM |
1323 | first_l_name = li->l_name; |
1324 | info->main_lm_addr = li->lm_addr; | |
cb08cc53 | 1325 | continue; |
93a57060 | 1326 | } |
13437d4b | 1327 | |
cb08cc53 | 1328 | /* Extract this shared object's name. */ |
d0e449a1 SM |
1329 | target_read_string (li->l_name, &buffer, SO_NAME_MAX_PATH_SIZE - 1, |
1330 | &errcode); | |
cb08cc53 JK |
1331 | if (errcode != 0) |
1332 | { | |
7d760051 UW |
1333 | /* If this entry's l_name address matches that of the |
1334 | inferior executable, then this is not a normal shared | |
1335 | object, but (most likely) a vDSO. In this case, silently | |
1336 | skip it; otherwise emit a warning. */ | |
d0e449a1 | 1337 | if (first_l_name == 0 || li->l_name != first_l_name) |
7d760051 UW |
1338 | warning (_("Can't read pathname for load map: %s."), |
1339 | safe_strerror (errcode)); | |
cb08cc53 | 1340 | continue; |
13437d4b KB |
1341 | } |
1342 | ||
e83e4e24 | 1343 | strncpy (newobj->so_name, buffer.get (), SO_NAME_MAX_PATH_SIZE - 1); |
fe978cb0 PA |
1344 | newobj->so_name[SO_NAME_MAX_PATH_SIZE - 1] = '\0'; |
1345 | strcpy (newobj->so_original_name, newobj->so_name); | |
492928e4 | 1346 | |
cb08cc53 JK |
1347 | /* If this entry has no name, or its name matches the name |
1348 | for the main executable, don't include it in the list. */ | |
fe978cb0 | 1349 | if (! newobj->so_name[0] || match_main (newobj->so_name)) |
b3bc8453 | 1350 | continue; |
e4cd0d6a | 1351 | |
fe978cb0 | 1352 | newobj->next = 0; |
b3bc8453 TT |
1353 | /* Don't free it now. */ |
1354 | **link_ptr_ptr = newobj.release (); | |
1355 | *link_ptr_ptr = &(**link_ptr_ptr)->next; | |
13437d4b | 1356 | } |
f9e14852 GB |
1357 | |
1358 | return 1; | |
cb08cc53 JK |
1359 | } |
1360 | ||
f9e14852 GB |
1361 | /* Read the full list of currently loaded shared objects directly |
1362 | from the inferior, without referring to any libraries read and | |
1363 | stored by the probes interface. Handle special cases relating | |
1364 | to the first elements of the list. */ | |
cb08cc53 JK |
1365 | |
1366 | static struct so_list * | |
f9e14852 | 1367 | svr4_current_sos_direct (struct svr4_info *info) |
cb08cc53 JK |
1368 | { |
1369 | CORE_ADDR lm; | |
1370 | struct so_list *head = NULL; | |
1371 | struct so_list **link_ptr = &head; | |
cb08cc53 | 1372 | int ignore_first; |
2268b414 JK |
1373 | struct svr4_library_list library_list; |
1374 | ||
0c5bf5a9 JK |
1375 | /* Fall back to manual examination of the target if the packet is not |
1376 | supported or gdbserver failed to find DT_DEBUG. gdb.server/solib-list.exp | |
1377 | tests a case where gdbserver cannot find the shared libraries list while | |
1378 | GDB itself is able to find it via SYMFILE_OBJFILE. | |
1379 | ||
1380 | Unfortunately statically linked inferiors will also fall back through this | |
1381 | suboptimal code path. */ | |
1382 | ||
f9e14852 GB |
1383 | info->using_xfer = svr4_current_sos_via_xfer_libraries (&library_list, |
1384 | NULL); | |
1385 | if (info->using_xfer) | |
2268b414 JK |
1386 | { |
1387 | if (library_list.main_lm) | |
f9e14852 | 1388 | info->main_lm_addr = library_list.main_lm; |
2268b414 | 1389 | |
d70cc3ba | 1390 | return library_list.head ? library_list.head : svr4_default_sos (info); |
2268b414 | 1391 | } |
cb08cc53 | 1392 | |
cb08cc53 JK |
1393 | /* Always locate the debug struct, in case it has moved. */ |
1394 | info->debug_base = 0; | |
1395 | locate_base (info); | |
1396 | ||
1397 | /* If we can't find the dynamic linker's base structure, this | |
1398 | must not be a dynamically linked executable. Hmm. */ | |
1399 | if (! info->debug_base) | |
d70cc3ba | 1400 | return svr4_default_sos (info); |
cb08cc53 JK |
1401 | |
1402 | /* Assume that everything is a library if the dynamic loader was loaded | |
1403 | late by a static executable. */ | |
1404 | if (exec_bfd && bfd_get_section_by_name (exec_bfd, ".dynamic") == NULL) | |
1405 | ignore_first = 0; | |
1406 | else | |
1407 | ignore_first = 1; | |
1408 | ||
2b6ff1c0 TT |
1409 | auto cleanup = make_scope_exit ([&] () |
1410 | { | |
1411 | svr4_free_library_list (&head); | |
1412 | }); | |
cb08cc53 JK |
1413 | |
1414 | /* Walk the inferior's link map list, and build our list of | |
1415 | `struct so_list' nodes. */ | |
1416 | lm = solib_svr4_r_map (info); | |
1417 | if (lm) | |
d70cc3ba | 1418 | svr4_read_so_list (info, lm, 0, &link_ptr, ignore_first); |
cb08cc53 JK |
1419 | |
1420 | /* On Solaris, the dynamic linker is not in the normal list of | |
1421 | shared objects, so make sure we pick it up too. Having | |
1422 | symbol information for the dynamic linker is quite crucial | |
1423 | for skipping dynamic linker resolver code. */ | |
1424 | lm = solib_svr4_r_ldsomap (info); | |
1425 | if (lm) | |
d70cc3ba | 1426 | svr4_read_so_list (info, lm, 0, &link_ptr, 0); |
cb08cc53 | 1427 | |
2b6ff1c0 | 1428 | cleanup.release (); |
13437d4b | 1429 | |
34439770 | 1430 | if (head == NULL) |
d70cc3ba | 1431 | return svr4_default_sos (info); |
34439770 | 1432 | |
13437d4b KB |
1433 | return head; |
1434 | } | |
1435 | ||
8b9a549d PA |
1436 | /* Implement the main part of the "current_sos" target_so_ops |
1437 | method. */ | |
f9e14852 GB |
1438 | |
1439 | static struct so_list * | |
d70cc3ba | 1440 | svr4_current_sos_1 (svr4_info *info) |
f9e14852 | 1441 | { |
f9e14852 GB |
1442 | /* If the solib list has been read and stored by the probes |
1443 | interface then we return a copy of the stored list. */ | |
1444 | if (info->solib_list != NULL) | |
1445 | return svr4_copy_library_list (info->solib_list); | |
1446 | ||
1447 | /* Otherwise obtain the solib list directly from the inferior. */ | |
1448 | return svr4_current_sos_direct (info); | |
1449 | } | |
1450 | ||
8b9a549d PA |
1451 | /* Implement the "current_sos" target_so_ops method. */ |
1452 | ||
1453 | static struct so_list * | |
1454 | svr4_current_sos (void) | |
1455 | { | |
d70cc3ba SM |
1456 | svr4_info *info = get_svr4_info (current_program_space); |
1457 | struct so_list *so_head = svr4_current_sos_1 (info); | |
8b9a549d PA |
1458 | struct mem_range vsyscall_range; |
1459 | ||
1460 | /* Filter out the vDSO module, if present. Its symbol file would | |
1461 | not be found on disk. The vDSO/vsyscall's OBJFILE is instead | |
1462 | managed by symfile-mem.c:add_vsyscall_page. */ | |
1463 | if (gdbarch_vsyscall_range (target_gdbarch (), &vsyscall_range) | |
1464 | && vsyscall_range.length != 0) | |
1465 | { | |
1466 | struct so_list **sop; | |
1467 | ||
1468 | sop = &so_head; | |
1469 | while (*sop != NULL) | |
1470 | { | |
1471 | struct so_list *so = *sop; | |
1472 | ||
1473 | /* We can't simply match the vDSO by starting address alone, | |
1474 | because lm_info->l_addr_inferior (and also l_addr) do not | |
1475 | necessarily represent the real starting address of the | |
1476 | ELF if the vDSO's ELF itself is "prelinked". The l_ld | |
1477 | field (the ".dynamic" section of the shared object) | |
1478 | always points at the absolute/resolved address though. | |
1479 | So check whether that address is inside the vDSO's | |
1480 | mapping instead. | |
1481 | ||
1482 | E.g., on Linux 3.16 (x86_64) the vDSO is a regular | |
1483 | 0-based ELF, and we see: | |
1484 | ||
1485 | (gdb) info auxv | |
1486 | 33 AT_SYSINFO_EHDR System-supplied DSO's ELF header 0x7ffff7ffb000 | |
1487 | (gdb) p/x *_r_debug.r_map.l_next | |
1488 | $1 = {l_addr = 0x7ffff7ffb000, ..., l_ld = 0x7ffff7ffb318, ...} | |
1489 | ||
1490 | And on Linux 2.6.32 (x86_64) we see: | |
1491 | ||
1492 | (gdb) info auxv | |
1493 | 33 AT_SYSINFO_EHDR System-supplied DSO's ELF header 0x7ffff7ffe000 | |
1494 | (gdb) p/x *_r_debug.r_map.l_next | |
1495 | $5 = {l_addr = 0x7ffff88fe000, ..., l_ld = 0x7ffff7ffe580, ... } | |
1496 | ||
1497 | Dumping that vDSO shows: | |
1498 | ||
1499 | (gdb) info proc mappings | |
1500 | 0x7ffff7ffe000 0x7ffff7fff000 0x1000 0 [vdso] | |
1501 | (gdb) dump memory vdso.bin 0x7ffff7ffe000 0x7ffff7fff000 | |
1502 | # readelf -Wa vdso.bin | |
1503 | [...] | |
1504 | Entry point address: 0xffffffffff700700 | |
1505 | [...] | |
1506 | Section Headers: | |
1507 | [Nr] Name Type Address Off Size | |
1508 | [ 0] NULL 0000000000000000 000000 000000 | |
1509 | [ 1] .hash HASH ffffffffff700120 000120 000038 | |
1510 | [ 2] .dynsym DYNSYM ffffffffff700158 000158 0000d8 | |
1511 | [...] | |
1512 | [ 9] .dynamic DYNAMIC ffffffffff700580 000580 0000f0 | |
1513 | */ | |
d0e449a1 SM |
1514 | |
1515 | lm_info_svr4 *li = (lm_info_svr4 *) so->lm_info; | |
1516 | ||
1517 | if (address_in_mem_range (li->l_ld, &vsyscall_range)) | |
8b9a549d PA |
1518 | { |
1519 | *sop = so->next; | |
1520 | free_so (so); | |
1521 | break; | |
1522 | } | |
1523 | ||
1524 | sop = &so->next; | |
1525 | } | |
1526 | } | |
1527 | ||
1528 | return so_head; | |
1529 | } | |
1530 | ||
93a57060 | 1531 | /* Get the address of the link_map for a given OBJFILE. */ |
bc4a16ae EZ |
1532 | |
1533 | CORE_ADDR | |
1534 | svr4_fetch_objfile_link_map (struct objfile *objfile) | |
1535 | { | |
93a57060 | 1536 | struct so_list *so; |
d70cc3ba | 1537 | struct svr4_info *info = get_svr4_info (objfile->pspace); |
bc4a16ae | 1538 | |
93a57060 | 1539 | /* Cause svr4_current_sos() to be run if it hasn't been already. */ |
1a816a87 | 1540 | if (info->main_lm_addr == 0) |
e696b3ad | 1541 | solib_add (NULL, 0, auto_solib_add); |
bc4a16ae | 1542 | |
93a57060 DJ |
1543 | /* svr4_current_sos() will set main_lm_addr for the main executable. */ |
1544 | if (objfile == symfile_objfile) | |
1a816a87 | 1545 | return info->main_lm_addr; |
93a57060 | 1546 | |
df22c1e5 JB |
1547 | /* If OBJFILE is a separate debug object file, look for the |
1548 | original object file. */ | |
1549 | if (objfile->separate_debug_objfile_backlink != NULL) | |
1550 | objfile = objfile->separate_debug_objfile_backlink; | |
1551 | ||
93a57060 DJ |
1552 | /* The other link map addresses may be found by examining the list |
1553 | of shared libraries. */ | |
1554 | for (so = master_so_list (); so; so = so->next) | |
1555 | if (so->objfile == objfile) | |
d0e449a1 SM |
1556 | { |
1557 | lm_info_svr4 *li = (lm_info_svr4 *) so->lm_info; | |
1558 | ||
1559 | return li->lm_addr; | |
1560 | } | |
93a57060 DJ |
1561 | |
1562 | /* Not found! */ | |
bc4a16ae EZ |
1563 | return 0; |
1564 | } | |
13437d4b KB |
1565 | |
1566 | /* On some systems, the only way to recognize the link map entry for | |
1567 | the main executable file is by looking at its name. Return | |
1568 | non-zero iff SONAME matches one of the known main executable names. */ | |
1569 | ||
1570 | static int | |
bc043ef3 | 1571 | match_main (const char *soname) |
13437d4b | 1572 | { |
bc043ef3 | 1573 | const char * const *mainp; |
13437d4b KB |
1574 | |
1575 | for (mainp = main_name_list; *mainp != NULL; mainp++) | |
1576 | { | |
1577 | if (strcmp (soname, *mainp) == 0) | |
1578 | return (1); | |
1579 | } | |
1580 | ||
1581 | return (0); | |
1582 | } | |
1583 | ||
13437d4b KB |
1584 | /* Return 1 if PC lies in the dynamic symbol resolution code of the |
1585 | SVR4 run time loader. */ | |
13437d4b | 1586 | |
7d522c90 | 1587 | int |
d7fa2ae2 | 1588 | svr4_in_dynsym_resolve_code (CORE_ADDR pc) |
13437d4b | 1589 | { |
d70cc3ba | 1590 | struct svr4_info *info = get_svr4_info (current_program_space); |
6c95b8df PA |
1591 | |
1592 | return ((pc >= info->interp_text_sect_low | |
1593 | && pc < info->interp_text_sect_high) | |
1594 | || (pc >= info->interp_plt_sect_low | |
1595 | && pc < info->interp_plt_sect_high) | |
3e5d3a5a | 1596 | || in_plt_section (pc) |
0875794a | 1597 | || in_gnu_ifunc_stub (pc)); |
13437d4b | 1598 | } |
13437d4b | 1599 | |
2f4950cd AC |
1600 | /* Given an executable's ABFD and target, compute the entry-point |
1601 | address. */ | |
1602 | ||
1603 | static CORE_ADDR | |
1604 | exec_entry_point (struct bfd *abfd, struct target_ops *targ) | |
1605 | { | |
8c2b9656 YQ |
1606 | CORE_ADDR addr; |
1607 | ||
2f4950cd AC |
1608 | /* KevinB wrote ... for most targets, the address returned by |
1609 | bfd_get_start_address() is the entry point for the start | |
1610 | function. But, for some targets, bfd_get_start_address() returns | |
1611 | the address of a function descriptor from which the entry point | |
1612 | address may be extracted. This address is extracted by | |
1613 | gdbarch_convert_from_func_ptr_addr(). The method | |
1614 | gdbarch_convert_from_func_ptr_addr() is the merely the identify | |
1615 | function for targets which don't use function descriptors. */ | |
8c2b9656 | 1616 | addr = gdbarch_convert_from_func_ptr_addr (target_gdbarch (), |
2f4950cd AC |
1617 | bfd_get_start_address (abfd), |
1618 | targ); | |
8c2b9656 | 1619 | return gdbarch_addr_bits_remove (target_gdbarch (), addr); |
2f4950cd | 1620 | } |
13437d4b | 1621 | |
f9e14852 GB |
1622 | /* A probe and its associated action. */ |
1623 | ||
1624 | struct probe_and_action | |
1625 | { | |
1626 | /* The probe. */ | |
935676c9 | 1627 | probe *prob; |
f9e14852 | 1628 | |
729662a5 TT |
1629 | /* The relocated address of the probe. */ |
1630 | CORE_ADDR address; | |
1631 | ||
f9e14852 GB |
1632 | /* The action. */ |
1633 | enum probe_action action; | |
7905fc35 PA |
1634 | |
1635 | /* The objfile where this probe was found. */ | |
1636 | struct objfile *objfile; | |
f9e14852 GB |
1637 | }; |
1638 | ||
1639 | /* Returns a hash code for the probe_and_action referenced by p. */ | |
1640 | ||
1641 | static hashval_t | |
1642 | hash_probe_and_action (const void *p) | |
1643 | { | |
19ba03f4 | 1644 | const struct probe_and_action *pa = (const struct probe_and_action *) p; |
f9e14852 | 1645 | |
729662a5 | 1646 | return (hashval_t) pa->address; |
f9e14852 GB |
1647 | } |
1648 | ||
1649 | /* Returns non-zero if the probe_and_actions referenced by p1 and p2 | |
1650 | are equal. */ | |
1651 | ||
1652 | static int | |
1653 | equal_probe_and_action (const void *p1, const void *p2) | |
1654 | { | |
19ba03f4 SM |
1655 | const struct probe_and_action *pa1 = (const struct probe_and_action *) p1; |
1656 | const struct probe_and_action *pa2 = (const struct probe_and_action *) p2; | |
f9e14852 | 1657 | |
729662a5 | 1658 | return pa1->address == pa2->address; |
f9e14852 GB |
1659 | } |
1660 | ||
7905fc35 PA |
1661 | /* Traversal function for probes_table_remove_objfile_probes. */ |
1662 | ||
1663 | static int | |
1664 | probes_table_htab_remove_objfile_probes (void **slot, void *info) | |
1665 | { | |
1666 | probe_and_action *pa = (probe_and_action *) *slot; | |
1667 | struct objfile *objfile = (struct objfile *) info; | |
1668 | ||
1669 | if (pa->objfile == objfile) | |
09232438 TT |
1670 | htab_clear_slot (get_svr4_info (objfile->pspace)->probes_table.get (), |
1671 | slot); | |
7905fc35 PA |
1672 | |
1673 | return 1; | |
1674 | } | |
1675 | ||
1676 | /* Remove all probes that belong to OBJFILE from the probes table. */ | |
1677 | ||
1678 | static void | |
1679 | probes_table_remove_objfile_probes (struct objfile *objfile) | |
1680 | { | |
d70cc3ba | 1681 | svr4_info *info = get_svr4_info (objfile->pspace); |
7905fc35 | 1682 | if (info->probes_table != nullptr) |
09232438 | 1683 | htab_traverse_noresize (info->probes_table.get (), |
7905fc35 PA |
1684 | probes_table_htab_remove_objfile_probes, objfile); |
1685 | } | |
1686 | ||
f9e14852 GB |
1687 | /* Register a solib event probe and its associated action in the |
1688 | probes table. */ | |
1689 | ||
1690 | static void | |
d70cc3ba | 1691 | register_solib_event_probe (svr4_info *info, struct objfile *objfile, |
7905fc35 | 1692 | probe *prob, CORE_ADDR address, |
729662a5 | 1693 | enum probe_action action) |
f9e14852 | 1694 | { |
f9e14852 GB |
1695 | struct probe_and_action lookup, *pa; |
1696 | void **slot; | |
1697 | ||
1698 | /* Create the probes table, if necessary. */ | |
1699 | if (info->probes_table == NULL) | |
09232438 TT |
1700 | info->probes_table.reset (htab_create_alloc (1, hash_probe_and_action, |
1701 | equal_probe_and_action, | |
1702 | xfree, xcalloc, xfree)); | |
f9e14852 | 1703 | |
729662a5 | 1704 | lookup.address = address; |
09232438 | 1705 | slot = htab_find_slot (info->probes_table.get (), &lookup, INSERT); |
f9e14852 GB |
1706 | gdb_assert (*slot == HTAB_EMPTY_ENTRY); |
1707 | ||
1708 | pa = XCNEW (struct probe_and_action); | |
935676c9 | 1709 | pa->prob = prob; |
729662a5 | 1710 | pa->address = address; |
f9e14852 | 1711 | pa->action = action; |
7905fc35 | 1712 | pa->objfile = objfile; |
f9e14852 GB |
1713 | |
1714 | *slot = pa; | |
1715 | } | |
1716 | ||
1717 | /* Get the solib event probe at the specified location, and the | |
1718 | action associated with it. Returns NULL if no solib event probe | |
1719 | was found. */ | |
1720 | ||
1721 | static struct probe_and_action * | |
1722 | solib_event_probe_at (struct svr4_info *info, CORE_ADDR address) | |
1723 | { | |
f9e14852 GB |
1724 | struct probe_and_action lookup; |
1725 | void **slot; | |
1726 | ||
729662a5 | 1727 | lookup.address = address; |
09232438 | 1728 | slot = htab_find_slot (info->probes_table.get (), &lookup, NO_INSERT); |
f9e14852 GB |
1729 | |
1730 | if (slot == NULL) | |
1731 | return NULL; | |
1732 | ||
1733 | return (struct probe_and_action *) *slot; | |
1734 | } | |
1735 | ||
1736 | /* Decide what action to take when the specified solib event probe is | |
1737 | hit. */ | |
1738 | ||
1739 | static enum probe_action | |
1740 | solib_event_probe_action (struct probe_and_action *pa) | |
1741 | { | |
1742 | enum probe_action action; | |
73c6b475 | 1743 | unsigned probe_argc = 0; |
08a6411c | 1744 | struct frame_info *frame = get_current_frame (); |
f9e14852 GB |
1745 | |
1746 | action = pa->action; | |
1747 | if (action == DO_NOTHING || action == PROBES_INTERFACE_FAILED) | |
1748 | return action; | |
1749 | ||
1750 | gdb_assert (action == FULL_RELOAD || action == UPDATE_OR_RELOAD); | |
1751 | ||
1752 | /* Check that an appropriate number of arguments has been supplied. | |
1753 | We expect: | |
1754 | arg0: Lmid_t lmid (mandatory) | |
1755 | arg1: struct r_debug *debug_base (mandatory) | |
1756 | arg2: struct link_map *new (optional, for incremental updates) */ | |
a70b8144 | 1757 | try |
3bd7e5b7 | 1758 | { |
935676c9 | 1759 | probe_argc = pa->prob->get_argument_count (frame); |
3bd7e5b7 | 1760 | } |
230d2906 | 1761 | catch (const gdb_exception_error &ex) |
3bd7e5b7 SDJ |
1762 | { |
1763 | exception_print (gdb_stderr, ex); | |
1764 | probe_argc = 0; | |
1765 | } | |
3bd7e5b7 | 1766 | |
935676c9 SDJ |
1767 | /* If get_argument_count throws an exception, probe_argc will be set |
1768 | to zero. However, if pa->prob does not have arguments, then | |
1769 | get_argument_count will succeed but probe_argc will also be zero. | |
1770 | Both cases happen because of different things, but they are | |
1771 | treated equally here: action will be set to | |
3bd7e5b7 | 1772 | PROBES_INTERFACE_FAILED. */ |
f9e14852 GB |
1773 | if (probe_argc == 2) |
1774 | action = FULL_RELOAD; | |
1775 | else if (probe_argc < 2) | |
1776 | action = PROBES_INTERFACE_FAILED; | |
1777 | ||
1778 | return action; | |
1779 | } | |
1780 | ||
1781 | /* Populate the shared object list by reading the entire list of | |
1782 | shared objects from the inferior. Handle special cases relating | |
1783 | to the first elements of the list. Returns nonzero on success. */ | |
1784 | ||
1785 | static int | |
1786 | solist_update_full (struct svr4_info *info) | |
1787 | { | |
1788 | free_solib_list (info); | |
1789 | info->solib_list = svr4_current_sos_direct (info); | |
1790 | ||
1791 | return 1; | |
1792 | } | |
1793 | ||
1794 | /* Update the shared object list starting from the link-map entry | |
1795 | passed by the linker in the probe's third argument. Returns | |
1796 | nonzero if the list was successfully updated, or zero to indicate | |
1797 | failure. */ | |
1798 | ||
1799 | static int | |
1800 | solist_update_incremental (struct svr4_info *info, CORE_ADDR lm) | |
1801 | { | |
1802 | struct so_list *tail; | |
1803 | CORE_ADDR prev_lm; | |
1804 | ||
1805 | /* svr4_current_sos_direct contains logic to handle a number of | |
1806 | special cases relating to the first elements of the list. To | |
1807 | avoid duplicating this logic we defer to solist_update_full | |
1808 | if the list is empty. */ | |
1809 | if (info->solib_list == NULL) | |
1810 | return 0; | |
1811 | ||
1812 | /* Fall back to a full update if we are using a remote target | |
1813 | that does not support incremental transfers. */ | |
1814 | if (info->using_xfer && !target_augmented_libraries_svr4_read ()) | |
1815 | return 0; | |
1816 | ||
1817 | /* Walk to the end of the list. */ | |
1818 | for (tail = info->solib_list; tail->next != NULL; tail = tail->next) | |
1819 | /* Nothing. */; | |
d0e449a1 SM |
1820 | |
1821 | lm_info_svr4 *li = (lm_info_svr4 *) tail->lm_info; | |
1822 | prev_lm = li->lm_addr; | |
f9e14852 GB |
1823 | |
1824 | /* Read the new objects. */ | |
1825 | if (info->using_xfer) | |
1826 | { | |
1827 | struct svr4_library_list library_list; | |
1828 | char annex[64]; | |
1829 | ||
1830 | xsnprintf (annex, sizeof (annex), "start=%s;prev=%s", | |
1831 | phex_nz (lm, sizeof (lm)), | |
1832 | phex_nz (prev_lm, sizeof (prev_lm))); | |
1833 | if (!svr4_current_sos_via_xfer_libraries (&library_list, annex)) | |
1834 | return 0; | |
1835 | ||
1836 | tail->next = library_list.head; | |
1837 | } | |
1838 | else | |
1839 | { | |
1840 | struct so_list **link = &tail->next; | |
1841 | ||
1842 | /* IGNORE_FIRST may safely be set to zero here because the | |
1843 | above check and deferral to solist_update_full ensures | |
1844 | that this call to svr4_read_so_list will never see the | |
1845 | first element. */ | |
d70cc3ba | 1846 | if (!svr4_read_so_list (info, lm, prev_lm, &link, 0)) |
f9e14852 GB |
1847 | return 0; |
1848 | } | |
1849 | ||
1850 | return 1; | |
1851 | } | |
1852 | ||
1853 | /* Disable the probes-based linker interface and revert to the | |
1854 | original interface. We don't reset the breakpoints as the | |
1855 | ones set up for the probes-based interface are adequate. */ | |
1856 | ||
1857 | static void | |
d70cc3ba | 1858 | disable_probes_interface (svr4_info *info) |
f9e14852 | 1859 | { |
f9e14852 | 1860 | warning (_("Probes-based dynamic linker interface failed.\n" |
422186a9 | 1861 | "Reverting to original interface.")); |
f9e14852 GB |
1862 | |
1863 | free_probes_table (info); | |
1864 | free_solib_list (info); | |
1865 | } | |
1866 | ||
1867 | /* Update the solib list as appropriate when using the | |
1868 | probes-based linker interface. Do nothing if using the | |
1869 | standard interface. */ | |
1870 | ||
1871 | static void | |
1872 | svr4_handle_solib_event (void) | |
1873 | { | |
d70cc3ba | 1874 | struct svr4_info *info = get_svr4_info (current_program_space); |
f9e14852 GB |
1875 | struct probe_and_action *pa; |
1876 | enum probe_action action; | |
ad1c917a | 1877 | struct value *val = NULL; |
f9e14852 | 1878 | CORE_ADDR pc, debug_base, lm = 0; |
08a6411c | 1879 | struct frame_info *frame = get_current_frame (); |
f9e14852 GB |
1880 | |
1881 | /* Do nothing if not using the probes interface. */ | |
1882 | if (info->probes_table == NULL) | |
1883 | return; | |
1884 | ||
1885 | /* If anything goes wrong we revert to the original linker | |
1886 | interface. */ | |
d70cc3ba SM |
1887 | auto cleanup = make_scope_exit ([info] () |
1888 | { | |
1889 | disable_probes_interface (info); | |
1890 | }); | |
f9e14852 GB |
1891 | |
1892 | pc = regcache_read_pc (get_current_regcache ()); | |
1893 | pa = solib_event_probe_at (info, pc); | |
1894 | if (pa == NULL) | |
d01c5877 | 1895 | return; |
f9e14852 GB |
1896 | |
1897 | action = solib_event_probe_action (pa); | |
1898 | if (action == PROBES_INTERFACE_FAILED) | |
d01c5877 | 1899 | return; |
f9e14852 GB |
1900 | |
1901 | if (action == DO_NOTHING) | |
1902 | { | |
d01c5877 | 1903 | cleanup.release (); |
f9e14852 GB |
1904 | return; |
1905 | } | |
1906 | ||
935676c9 | 1907 | /* evaluate_argument looks up symbols in the dynamic linker |
f9e14852 GB |
1908 | using find_pc_section. find_pc_section is accelerated by a cache |
1909 | called the section map. The section map is invalidated every | |
1910 | time a shared library is loaded or unloaded, and if the inferior | |
1911 | is generating a lot of shared library events then the section map | |
1912 | will be updated every time svr4_handle_solib_event is called. | |
1913 | We called find_pc_section in svr4_create_solib_event_breakpoints, | |
1914 | so we can guarantee that the dynamic linker's sections are in the | |
1915 | section map. We can therefore inhibit section map updates across | |
935676c9 | 1916 | these calls to evaluate_argument and save a lot of time. */ |
06424eac TT |
1917 | { |
1918 | scoped_restore inhibit_updates | |
1919 | = inhibit_section_map_updates (current_program_space); | |
f9e14852 | 1920 | |
a70b8144 | 1921 | try |
06424eac TT |
1922 | { |
1923 | val = pa->prob->evaluate_argument (1, frame); | |
1924 | } | |
230d2906 | 1925 | catch (const gdb_exception_error &ex) |
06424eac TT |
1926 | { |
1927 | exception_print (gdb_stderr, ex); | |
1928 | val = NULL; | |
1929 | } | |
f9e14852 | 1930 | |
06424eac | 1931 | if (val == NULL) |
d01c5877 | 1932 | return; |
f9e14852 | 1933 | |
06424eac TT |
1934 | debug_base = value_as_address (val); |
1935 | if (debug_base == 0) | |
d01c5877 | 1936 | return; |
f9e14852 | 1937 | |
06424eac TT |
1938 | /* Always locate the debug struct, in case it moved. */ |
1939 | info->debug_base = 0; | |
1940 | if (locate_base (info) == 0) | |
d01c5877 | 1941 | return; |
3bd7e5b7 | 1942 | |
06424eac TT |
1943 | /* GDB does not currently support libraries loaded via dlmopen |
1944 | into namespaces other than the initial one. We must ignore | |
1945 | any namespace other than the initial namespace here until | |
1946 | support for this is added to GDB. */ | |
1947 | if (debug_base != info->debug_base) | |
1948 | action = DO_NOTHING; | |
f9e14852 | 1949 | |
06424eac TT |
1950 | if (action == UPDATE_OR_RELOAD) |
1951 | { | |
a70b8144 | 1952 | try |
06424eac TT |
1953 | { |
1954 | val = pa->prob->evaluate_argument (2, frame); | |
1955 | } | |
230d2906 | 1956 | catch (const gdb_exception_error &ex) |
06424eac TT |
1957 | { |
1958 | exception_print (gdb_stderr, ex); | |
06424eac TT |
1959 | return; |
1960 | } | |
06424eac TT |
1961 | |
1962 | if (val != NULL) | |
1963 | lm = value_as_address (val); | |
1964 | ||
1965 | if (lm == 0) | |
1966 | action = FULL_RELOAD; | |
1967 | } | |
f9e14852 | 1968 | |
06424eac TT |
1969 | /* Resume section map updates. Closing the scope is |
1970 | sufficient. */ | |
1971 | } | |
f9e14852 GB |
1972 | |
1973 | if (action == UPDATE_OR_RELOAD) | |
1974 | { | |
1975 | if (!solist_update_incremental (info, lm)) | |
1976 | action = FULL_RELOAD; | |
1977 | } | |
1978 | ||
1979 | if (action == FULL_RELOAD) | |
1980 | { | |
1981 | if (!solist_update_full (info)) | |
d01c5877 | 1982 | return; |
f9e14852 GB |
1983 | } |
1984 | ||
d01c5877 | 1985 | cleanup.release (); |
f9e14852 GB |
1986 | } |
1987 | ||
1988 | /* Helper function for svr4_update_solib_event_breakpoints. */ | |
1989 | ||
1990 | static int | |
1991 | svr4_update_solib_event_breakpoint (struct breakpoint *b, void *arg) | |
1992 | { | |
1993 | struct bp_location *loc; | |
1994 | ||
1995 | if (b->type != bp_shlib_event) | |
1996 | { | |
1997 | /* Continue iterating. */ | |
1998 | return 0; | |
1999 | } | |
2000 | ||
2001 | for (loc = b->loc; loc != NULL; loc = loc->next) | |
2002 | { | |
2003 | struct svr4_info *info; | |
2004 | struct probe_and_action *pa; | |
2005 | ||
09232438 | 2006 | info = solib_svr4_pspace_data.get (loc->pspace); |
f9e14852 GB |
2007 | if (info == NULL || info->probes_table == NULL) |
2008 | continue; | |
2009 | ||
2010 | pa = solib_event_probe_at (info, loc->address); | |
2011 | if (pa == NULL) | |
2012 | continue; | |
2013 | ||
2014 | if (pa->action == DO_NOTHING) | |
2015 | { | |
2016 | if (b->enable_state == bp_disabled && stop_on_solib_events) | |
2017 | enable_breakpoint (b); | |
2018 | else if (b->enable_state == bp_enabled && !stop_on_solib_events) | |
2019 | disable_breakpoint (b); | |
2020 | } | |
2021 | ||
2022 | break; | |
2023 | } | |
2024 | ||
2025 | /* Continue iterating. */ | |
2026 | return 0; | |
2027 | } | |
2028 | ||
2029 | /* Enable or disable optional solib event breakpoints as appropriate. | |
2030 | Called whenever stop_on_solib_events is changed. */ | |
2031 | ||
2032 | static void | |
2033 | svr4_update_solib_event_breakpoints (void) | |
2034 | { | |
2035 | iterate_over_breakpoints (svr4_update_solib_event_breakpoint, NULL); | |
2036 | } | |
2037 | ||
2038 | /* Create and register solib event breakpoints. PROBES is an array | |
2039 | of NUM_PROBES elements, each of which is vector of probes. A | |
2040 | solib event breakpoint will be created and registered for each | |
2041 | probe. */ | |
2042 | ||
2043 | static void | |
d70cc3ba | 2044 | svr4_create_probe_breakpoints (svr4_info *info, struct gdbarch *gdbarch, |
45461e0d | 2045 | const std::vector<probe *> *probes, |
729662a5 | 2046 | struct objfile *objfile) |
f9e14852 | 2047 | { |
45461e0d | 2048 | for (int i = 0; i < NUM_PROBES; i++) |
f9e14852 GB |
2049 | { |
2050 | enum probe_action action = probe_info[i].action; | |
f9e14852 | 2051 | |
45461e0d | 2052 | for (probe *p : probes[i]) |
f9e14852 | 2053 | { |
935676c9 | 2054 | CORE_ADDR address = p->get_relocated_address (objfile); |
729662a5 TT |
2055 | |
2056 | create_solib_event_breakpoint (gdbarch, address); | |
d70cc3ba | 2057 | register_solib_event_probe (info, objfile, p, address, action); |
f9e14852 GB |
2058 | } |
2059 | } | |
2060 | ||
2061 | svr4_update_solib_event_breakpoints (); | |
2062 | } | |
2063 | ||
2064 | /* Both the SunOS and the SVR4 dynamic linkers call a marker function | |
2065 | before and after mapping and unmapping shared libraries. The sole | |
2066 | purpose of this method is to allow debuggers to set a breakpoint so | |
2067 | they can track these changes. | |
2068 | ||
2069 | Some versions of the glibc dynamic linker contain named probes | |
2070 | to allow more fine grained stopping. Given the address of the | |
2071 | original marker function, this function attempts to find these | |
2072 | probes, and if found, sets breakpoints on those instead. If the | |
2073 | probes aren't found, a single breakpoint is set on the original | |
2074 | marker function. */ | |
2075 | ||
2076 | static void | |
d70cc3ba | 2077 | svr4_create_solib_event_breakpoints (svr4_info *info, struct gdbarch *gdbarch, |
f9e14852 GB |
2078 | CORE_ADDR address) |
2079 | { | |
2080 | struct obj_section *os; | |
2081 | ||
2082 | os = find_pc_section (address); | |
2083 | if (os != NULL) | |
2084 | { | |
2085 | int with_prefix; | |
2086 | ||
2087 | for (with_prefix = 0; with_prefix <= 1; with_prefix++) | |
2088 | { | |
45461e0d | 2089 | std::vector<probe *> probes[NUM_PROBES]; |
f9e14852 | 2090 | int all_probes_found = 1; |
25f9533e | 2091 | int checked_can_use_probe_arguments = 0; |
f9e14852 | 2092 | |
45461e0d | 2093 | for (int i = 0; i < NUM_PROBES; i++) |
f9e14852 GB |
2094 | { |
2095 | const char *name = probe_info[i].name; | |
935676c9 | 2096 | probe *p; |
f9e14852 GB |
2097 | char buf[32]; |
2098 | ||
2099 | /* Fedora 17 and Red Hat Enterprise Linux 6.2-6.4 | |
2100 | shipped with an early version of the probes code in | |
2101 | which the probes' names were prefixed with "rtld_" | |
2102 | and the "map_failed" probe did not exist. The | |
2103 | locations of the probes are otherwise the same, so | |
2104 | we check for probes with prefixed names if probes | |
2105 | with unprefixed names are not present. */ | |
2106 | if (with_prefix) | |
2107 | { | |
2108 | xsnprintf (buf, sizeof (buf), "rtld_%s", name); | |
2109 | name = buf; | |
2110 | } | |
2111 | ||
2112 | probes[i] = find_probes_in_objfile (os->objfile, "rtld", name); | |
2113 | ||
2114 | /* The "map_failed" probe did not exist in early | |
2115 | versions of the probes code in which the probes' | |
2116 | names were prefixed with "rtld_". */ | |
2117 | if (strcmp (name, "rtld_map_failed") == 0) | |
2118 | continue; | |
2119 | ||
45461e0d | 2120 | if (probes[i].empty ()) |
f9e14852 GB |
2121 | { |
2122 | all_probes_found = 0; | |
2123 | break; | |
2124 | } | |
25f9533e SDJ |
2125 | |
2126 | /* Ensure probe arguments can be evaluated. */ | |
2127 | if (!checked_can_use_probe_arguments) | |
2128 | { | |
45461e0d | 2129 | p = probes[i][0]; |
935676c9 | 2130 | if (!p->can_evaluate_arguments ()) |
25f9533e SDJ |
2131 | { |
2132 | all_probes_found = 0; | |
2133 | break; | |
2134 | } | |
2135 | checked_can_use_probe_arguments = 1; | |
2136 | } | |
f9e14852 GB |
2137 | } |
2138 | ||
2139 | if (all_probes_found) | |
d70cc3ba | 2140 | svr4_create_probe_breakpoints (info, gdbarch, probes, os->objfile); |
f9e14852 | 2141 | |
f9e14852 GB |
2142 | if (all_probes_found) |
2143 | return; | |
2144 | } | |
2145 | } | |
2146 | ||
2147 | create_solib_event_breakpoint (gdbarch, address); | |
2148 | } | |
2149 | ||
cb457ae2 YQ |
2150 | /* Helper function for gdb_bfd_lookup_symbol. */ |
2151 | ||
2152 | static int | |
3953f15c | 2153 | cmp_name_and_sec_flags (const asymbol *sym, const void *data) |
cb457ae2 YQ |
2154 | { |
2155 | return (strcmp (sym->name, (const char *) data) == 0 | |
2156 | && (sym->section->flags & (SEC_CODE | SEC_DATA)) != 0); | |
2157 | } | |
7f86f058 | 2158 | /* Arrange for dynamic linker to hit breakpoint. |
13437d4b KB |
2159 | |
2160 | Both the SunOS and the SVR4 dynamic linkers have, as part of their | |
2161 | debugger interface, support for arranging for the inferior to hit | |
2162 | a breakpoint after mapping in the shared libraries. This function | |
2163 | enables that breakpoint. | |
2164 | ||
2165 | For SunOS, there is a special flag location (in_debugger) which we | |
2166 | set to 1. When the dynamic linker sees this flag set, it will set | |
2167 | a breakpoint at a location known only to itself, after saving the | |
2168 | original contents of that place and the breakpoint address itself, | |
2169 | in it's own internal structures. When we resume the inferior, it | |
2170 | will eventually take a SIGTRAP when it runs into the breakpoint. | |
2171 | We handle this (in a different place) by restoring the contents of | |
2172 | the breakpointed location (which is only known after it stops), | |
2173 | chasing around to locate the shared libraries that have been | |
2174 | loaded, then resuming. | |
2175 | ||
2176 | For SVR4, the debugger interface structure contains a member (r_brk) | |
2177 | which is statically initialized at the time the shared library is | |
2178 | built, to the offset of a function (_r_debug_state) which is guaran- | |
2179 | teed to be called once before mapping in a library, and again when | |
2180 | the mapping is complete. At the time we are examining this member, | |
2181 | it contains only the unrelocated offset of the function, so we have | |
2182 | to do our own relocation. Later, when the dynamic linker actually | |
2183 | runs, it relocates r_brk to be the actual address of _r_debug_state(). | |
2184 | ||
2185 | The debugger interface structure also contains an enumeration which | |
2186 | is set to either RT_ADD or RT_DELETE prior to changing the mapping, | |
2187 | depending upon whether or not the library is being mapped or unmapped, | |
7f86f058 | 2188 | and then set to RT_CONSISTENT after the library is mapped/unmapped. */ |
13437d4b KB |
2189 | |
2190 | static int | |
268a4a75 | 2191 | enable_break (struct svr4_info *info, int from_tty) |
13437d4b | 2192 | { |
3b7344d5 | 2193 | struct bound_minimal_symbol msymbol; |
bc043ef3 | 2194 | const char * const *bkpt_namep; |
13437d4b | 2195 | asection *interp_sect; |
7cd25cfc | 2196 | CORE_ADDR sym_addr; |
13437d4b | 2197 | |
6c95b8df PA |
2198 | info->interp_text_sect_low = info->interp_text_sect_high = 0; |
2199 | info->interp_plt_sect_low = info->interp_plt_sect_high = 0; | |
13437d4b | 2200 | |
7cd25cfc DJ |
2201 | /* If we already have a shared library list in the target, and |
2202 | r_debug contains r_brk, set the breakpoint there - this should | |
2203 | mean r_brk has already been relocated. Assume the dynamic linker | |
2204 | is the object containing r_brk. */ | |
2205 | ||
e696b3ad | 2206 | solib_add (NULL, from_tty, auto_solib_add); |
7cd25cfc | 2207 | sym_addr = 0; |
1a816a87 PA |
2208 | if (info->debug_base && solib_svr4_r_map (info) != 0) |
2209 | sym_addr = solib_svr4_r_brk (info); | |
7cd25cfc DJ |
2210 | |
2211 | if (sym_addr != 0) | |
2212 | { | |
2213 | struct obj_section *os; | |
2214 | ||
b36ec657 | 2215 | sym_addr = gdbarch_addr_bits_remove |
8b88a78e PA |
2216 | (target_gdbarch (), |
2217 | gdbarch_convert_from_func_ptr_addr (target_gdbarch (), | |
2218 | sym_addr, | |
2219 | current_top_target ())); | |
b36ec657 | 2220 | |
48379de6 DE |
2221 | /* On at least some versions of Solaris there's a dynamic relocation |
2222 | on _r_debug.r_brk and SYM_ADDR may not be relocated yet, e.g., if | |
2223 | we get control before the dynamic linker has self-relocated. | |
2224 | Check if SYM_ADDR is in a known section, if it is assume we can | |
2225 | trust its value. This is just a heuristic though, it could go away | |
2226 | or be replaced if it's getting in the way. | |
2227 | ||
2228 | On ARM we need to know whether the ISA of rtld_db_dlactivity (or | |
2229 | however it's spelled in your particular system) is ARM or Thumb. | |
2230 | That knowledge is encoded in the address, if it's Thumb the low bit | |
2231 | is 1. However, we've stripped that info above and it's not clear | |
2232 | what all the consequences are of passing a non-addr_bits_remove'd | |
f9e14852 | 2233 | address to svr4_create_solib_event_breakpoints. The call to |
48379de6 DE |
2234 | find_pc_section verifies we know about the address and have some |
2235 | hope of computing the right kind of breakpoint to use (via | |
2236 | symbol info). It does mean that GDB needs to be pointed at a | |
2237 | non-stripped version of the dynamic linker in order to obtain | |
2238 | information it already knows about. Sigh. */ | |
2239 | ||
7cd25cfc DJ |
2240 | os = find_pc_section (sym_addr); |
2241 | if (os != NULL) | |
2242 | { | |
2243 | /* Record the relocated start and end address of the dynamic linker | |
2244 | text and plt section for svr4_in_dynsym_resolve_code. */ | |
2245 | bfd *tmp_bfd; | |
2246 | CORE_ADDR load_addr; | |
2247 | ||
2248 | tmp_bfd = os->objfile->obfd; | |
2249 | load_addr = ANOFFSET (os->objfile->section_offsets, | |
e03e6279 | 2250 | SECT_OFF_TEXT (os->objfile)); |
7cd25cfc DJ |
2251 | |
2252 | interp_sect = bfd_get_section_by_name (tmp_bfd, ".text"); | |
2253 | if (interp_sect) | |
2254 | { | |
6c95b8df | 2255 | info->interp_text_sect_low = |
7cd25cfc | 2256 | bfd_section_vma (tmp_bfd, interp_sect) + load_addr; |
6c95b8df PA |
2257 | info->interp_text_sect_high = |
2258 | info->interp_text_sect_low | |
2259 | + bfd_section_size (tmp_bfd, interp_sect); | |
7cd25cfc DJ |
2260 | } |
2261 | interp_sect = bfd_get_section_by_name (tmp_bfd, ".plt"); | |
2262 | if (interp_sect) | |
2263 | { | |
6c95b8df | 2264 | info->interp_plt_sect_low = |
7cd25cfc | 2265 | bfd_section_vma (tmp_bfd, interp_sect) + load_addr; |
6c95b8df PA |
2266 | info->interp_plt_sect_high = |
2267 | info->interp_plt_sect_low | |
2268 | + bfd_section_size (tmp_bfd, interp_sect); | |
7cd25cfc DJ |
2269 | } |
2270 | ||
d70cc3ba | 2271 | svr4_create_solib_event_breakpoints (info, target_gdbarch (), sym_addr); |
7cd25cfc DJ |
2272 | return 1; |
2273 | } | |
2274 | } | |
2275 | ||
97ec2c2f | 2276 | /* Find the program interpreter; if not found, warn the user and drop |
13437d4b | 2277 | into the old breakpoint at symbol code. */ |
17658d46 SM |
2278 | gdb::optional<gdb::byte_vector> interp_name_holder |
2279 | = find_program_interpreter (); | |
2280 | if (interp_name_holder) | |
13437d4b | 2281 | { |
17658d46 | 2282 | const char *interp_name = (const char *) interp_name_holder->data (); |
8ad2fcde KB |
2283 | CORE_ADDR load_addr = 0; |
2284 | int load_addr_found = 0; | |
2ec9a4f8 | 2285 | int loader_found_in_list = 0; |
f8766ec1 | 2286 | struct so_list *so; |
2f4950cd | 2287 | struct target_ops *tmp_bfd_target; |
13437d4b | 2288 | |
7cd25cfc | 2289 | sym_addr = 0; |
13437d4b KB |
2290 | |
2291 | /* Now we need to figure out where the dynamic linker was | |
2292 | loaded so that we can load its symbols and place a breakpoint | |
2293 | in the dynamic linker itself. | |
2294 | ||
2295 | This address is stored on the stack. However, I've been unable | |
2296 | to find any magic formula to find it for Solaris (appears to | |
2297 | be trivial on GNU/Linux). Therefore, we have to try an alternate | |
2298 | mechanism to find the dynamic linker's base address. */ | |
e4f7b8c8 | 2299 | |
192b62ce | 2300 | gdb_bfd_ref_ptr tmp_bfd; |
a70b8144 | 2301 | try |
f1838a98 | 2302 | { |
97ec2c2f | 2303 | tmp_bfd = solib_bfd_open (interp_name); |
f1838a98 | 2304 | } |
230d2906 | 2305 | catch (const gdb_exception &ex) |
492d29ea PA |
2306 | { |
2307 | } | |
492d29ea | 2308 | |
13437d4b KB |
2309 | if (tmp_bfd == NULL) |
2310 | goto bkpt_at_symbol; | |
2311 | ||
2f4950cd | 2312 | /* Now convert the TMP_BFD into a target. That way target, as |
192b62ce TT |
2313 | well as BFD operations can be used. target_bfd_reopen |
2314 | acquires its own reference. */ | |
2315 | tmp_bfd_target = target_bfd_reopen (tmp_bfd.get ()); | |
2f4950cd | 2316 | |
f8766ec1 KB |
2317 | /* On a running target, we can get the dynamic linker's base |
2318 | address from the shared library table. */ | |
f8766ec1 KB |
2319 | so = master_so_list (); |
2320 | while (so) | |
8ad2fcde | 2321 | { |
97ec2c2f | 2322 | if (svr4_same_1 (interp_name, so->so_original_name)) |
8ad2fcde KB |
2323 | { |
2324 | load_addr_found = 1; | |
2ec9a4f8 | 2325 | loader_found_in_list = 1; |
192b62ce | 2326 | load_addr = lm_addr_check (so, tmp_bfd.get ()); |
8ad2fcde KB |
2327 | break; |
2328 | } | |
f8766ec1 | 2329 | so = so->next; |
8ad2fcde KB |
2330 | } |
2331 | ||
8d4e36ba JB |
2332 | /* If we were not able to find the base address of the loader |
2333 | from our so_list, then try using the AT_BASE auxilliary entry. */ | |
2334 | if (!load_addr_found) | |
8b88a78e | 2335 | if (target_auxv_search (current_top_target (), AT_BASE, &load_addr) > 0) |
ad3a0e5b | 2336 | { |
f5656ead | 2337 | int addr_bit = gdbarch_addr_bit (target_gdbarch ()); |
ad3a0e5b JK |
2338 | |
2339 | /* Ensure LOAD_ADDR has proper sign in its possible upper bits so | |
2340 | that `+ load_addr' will overflow CORE_ADDR width not creating | |
2341 | invalid addresses like 0x101234567 for 32bit inferiors on 64bit | |
2342 | GDB. */ | |
2343 | ||
d182d057 | 2344 | if (addr_bit < (sizeof (CORE_ADDR) * HOST_CHAR_BIT)) |
ad3a0e5b | 2345 | { |
d182d057 | 2346 | CORE_ADDR space_size = (CORE_ADDR) 1 << addr_bit; |
192b62ce | 2347 | CORE_ADDR tmp_entry_point = exec_entry_point (tmp_bfd.get (), |
ad3a0e5b JK |
2348 | tmp_bfd_target); |
2349 | ||
2350 | gdb_assert (load_addr < space_size); | |
2351 | ||
2352 | /* TMP_ENTRY_POINT exceeding SPACE_SIZE would be for prelinked | |
2353 | 64bit ld.so with 32bit executable, it should not happen. */ | |
2354 | ||
2355 | if (tmp_entry_point < space_size | |
2356 | && tmp_entry_point + load_addr >= space_size) | |
2357 | load_addr -= space_size; | |
2358 | } | |
2359 | ||
2360 | load_addr_found = 1; | |
2361 | } | |
8d4e36ba | 2362 | |
8ad2fcde KB |
2363 | /* Otherwise we find the dynamic linker's base address by examining |
2364 | the current pc (which should point at the entry point for the | |
8d4e36ba JB |
2365 | dynamic linker) and subtracting the offset of the entry point. |
2366 | ||
2367 | This is more fragile than the previous approaches, but is a good | |
2368 | fallback method because it has actually been working well in | |
2369 | most cases. */ | |
8ad2fcde | 2370 | if (!load_addr_found) |
fb14de7b | 2371 | { |
c2250ad1 | 2372 | struct regcache *regcache |
f5656ead | 2373 | = get_thread_arch_regcache (inferior_ptid, target_gdbarch ()); |
433759f7 | 2374 | |
fb14de7b | 2375 | load_addr = (regcache_read_pc (regcache) |
192b62ce | 2376 | - exec_entry_point (tmp_bfd.get (), tmp_bfd_target)); |
fb14de7b | 2377 | } |
2ec9a4f8 DJ |
2378 | |
2379 | if (!loader_found_in_list) | |
34439770 | 2380 | { |
1a816a87 PA |
2381 | info->debug_loader_name = xstrdup (interp_name); |
2382 | info->debug_loader_offset_p = 1; | |
2383 | info->debug_loader_offset = load_addr; | |
e696b3ad | 2384 | solib_add (NULL, from_tty, auto_solib_add); |
34439770 | 2385 | } |
13437d4b KB |
2386 | |
2387 | /* Record the relocated start and end address of the dynamic linker | |
d7fa2ae2 | 2388 | text and plt section for svr4_in_dynsym_resolve_code. */ |
192b62ce | 2389 | interp_sect = bfd_get_section_by_name (tmp_bfd.get (), ".text"); |
13437d4b KB |
2390 | if (interp_sect) |
2391 | { | |
6c95b8df | 2392 | info->interp_text_sect_low = |
192b62ce | 2393 | bfd_section_vma (tmp_bfd.get (), interp_sect) + load_addr; |
6c95b8df PA |
2394 | info->interp_text_sect_high = |
2395 | info->interp_text_sect_low | |
192b62ce | 2396 | + bfd_section_size (tmp_bfd.get (), interp_sect); |
13437d4b | 2397 | } |
192b62ce | 2398 | interp_sect = bfd_get_section_by_name (tmp_bfd.get (), ".plt"); |
13437d4b KB |
2399 | if (interp_sect) |
2400 | { | |
6c95b8df | 2401 | info->interp_plt_sect_low = |
192b62ce | 2402 | bfd_section_vma (tmp_bfd.get (), interp_sect) + load_addr; |
6c95b8df PA |
2403 | info->interp_plt_sect_high = |
2404 | info->interp_plt_sect_low | |
192b62ce | 2405 | + bfd_section_size (tmp_bfd.get (), interp_sect); |
13437d4b KB |
2406 | } |
2407 | ||
2408 | /* Now try to set a breakpoint in the dynamic linker. */ | |
2409 | for (bkpt_namep = solib_break_names; *bkpt_namep != NULL; bkpt_namep++) | |
2410 | { | |
192b62ce TT |
2411 | sym_addr = gdb_bfd_lookup_symbol (tmp_bfd.get (), |
2412 | cmp_name_and_sec_flags, | |
3953f15c | 2413 | *bkpt_namep); |
13437d4b KB |
2414 | if (sym_addr != 0) |
2415 | break; | |
2416 | } | |
2417 | ||
2bbe3cc1 DJ |
2418 | if (sym_addr != 0) |
2419 | /* Convert 'sym_addr' from a function pointer to an address. | |
2420 | Because we pass tmp_bfd_target instead of the current | |
2421 | target, this will always produce an unrelocated value. */ | |
f5656ead | 2422 | sym_addr = gdbarch_convert_from_func_ptr_addr (target_gdbarch (), |
2bbe3cc1 DJ |
2423 | sym_addr, |
2424 | tmp_bfd_target); | |
2425 | ||
695c3173 TT |
2426 | /* We're done with both the temporary bfd and target. Closing |
2427 | the target closes the underlying bfd, because it holds the | |
2428 | only remaining reference. */ | |
460014f5 | 2429 | target_close (tmp_bfd_target); |
13437d4b KB |
2430 | |
2431 | if (sym_addr != 0) | |
2432 | { | |
d70cc3ba | 2433 | svr4_create_solib_event_breakpoints (info, target_gdbarch (), |
f9e14852 | 2434 | load_addr + sym_addr); |
13437d4b KB |
2435 | return 1; |
2436 | } | |
2437 | ||
2438 | /* For whatever reason we couldn't set a breakpoint in the dynamic | |
2439 | linker. Warn and drop into the old code. */ | |
2440 | bkpt_at_symbol: | |
82d03102 PG |
2441 | warning (_("Unable to find dynamic linker breakpoint function.\n" |
2442 | "GDB will be unable to debug shared library initializers\n" | |
2443 | "and track explicitly loaded dynamic code.")); | |
13437d4b | 2444 | } |
13437d4b | 2445 | |
e499d0f1 DJ |
2446 | /* Scan through the lists of symbols, trying to look up the symbol and |
2447 | set a breakpoint there. Terminate loop when we/if we succeed. */ | |
2448 | ||
2449 | for (bkpt_namep = solib_break_names; *bkpt_namep != NULL; bkpt_namep++) | |
2450 | { | |
2451 | msymbol = lookup_minimal_symbol (*bkpt_namep, NULL, symfile_objfile); | |
3b7344d5 | 2452 | if ((msymbol.minsym != NULL) |
77e371c0 | 2453 | && (BMSYMBOL_VALUE_ADDRESS (msymbol) != 0)) |
e499d0f1 | 2454 | { |
77e371c0 | 2455 | sym_addr = BMSYMBOL_VALUE_ADDRESS (msymbol); |
f5656ead | 2456 | sym_addr = gdbarch_convert_from_func_ptr_addr (target_gdbarch (), |
de64a9ac | 2457 | sym_addr, |
8b88a78e | 2458 | current_top_target ()); |
d70cc3ba SM |
2459 | svr4_create_solib_event_breakpoints (info, target_gdbarch (), |
2460 | sym_addr); | |
e499d0f1 DJ |
2461 | return 1; |
2462 | } | |
2463 | } | |
13437d4b | 2464 | |
17658d46 | 2465 | if (interp_name_holder && !current_inferior ()->attach_flag) |
13437d4b | 2466 | { |
c6490bf2 | 2467 | for (bkpt_namep = bkpt_names; *bkpt_namep != NULL; bkpt_namep++) |
13437d4b | 2468 | { |
c6490bf2 | 2469 | msymbol = lookup_minimal_symbol (*bkpt_namep, NULL, symfile_objfile); |
3b7344d5 | 2470 | if ((msymbol.minsym != NULL) |
77e371c0 | 2471 | && (BMSYMBOL_VALUE_ADDRESS (msymbol) != 0)) |
c6490bf2 | 2472 | { |
77e371c0 | 2473 | sym_addr = BMSYMBOL_VALUE_ADDRESS (msymbol); |
f5656ead | 2474 | sym_addr = gdbarch_convert_from_func_ptr_addr (target_gdbarch (), |
c6490bf2 | 2475 | sym_addr, |
8b88a78e | 2476 | current_top_target ()); |
d70cc3ba SM |
2477 | svr4_create_solib_event_breakpoints (info, target_gdbarch (), |
2478 | sym_addr); | |
c6490bf2 KB |
2479 | return 1; |
2480 | } | |
13437d4b KB |
2481 | } |
2482 | } | |
542c95c2 | 2483 | return 0; |
13437d4b KB |
2484 | } |
2485 | ||
d1012b8e | 2486 | /* Read the ELF program headers from ABFD. */ |
e2a44558 | 2487 | |
d1012b8e SM |
2488 | static gdb::optional<gdb::byte_vector> |
2489 | read_program_headers_from_bfd (bfd *abfd) | |
e2a44558 | 2490 | { |
d1012b8e SM |
2491 | Elf_Internal_Ehdr *ehdr = elf_elfheader (abfd); |
2492 | int phdrs_size = ehdr->e_phnum * ehdr->e_phentsize; | |
2493 | if (phdrs_size == 0) | |
2494 | return {}; | |
09919ac2 | 2495 | |
d1012b8e | 2496 | gdb::byte_vector buf (phdrs_size); |
09919ac2 | 2497 | if (bfd_seek (abfd, ehdr->e_phoff, SEEK_SET) != 0 |
d1012b8e SM |
2498 | || bfd_bread (buf.data (), phdrs_size, abfd) != phdrs_size) |
2499 | return {}; | |
09919ac2 JK |
2500 | |
2501 | return buf; | |
b8040f19 JK |
2502 | } |
2503 | ||
01c30d6e JK |
2504 | /* Return 1 and fill *DISPLACEMENTP with detected PIE offset of inferior |
2505 | exec_bfd. Otherwise return 0. | |
2506 | ||
2507 | We relocate all of the sections by the same amount. This | |
c378eb4e | 2508 | behavior is mandated by recent editions of the System V ABI. |
b8040f19 JK |
2509 | According to the System V Application Binary Interface, |
2510 | Edition 4.1, page 5-5: | |
2511 | ||
2512 | ... Though the system chooses virtual addresses for | |
2513 | individual processes, it maintains the segments' relative | |
2514 | positions. Because position-independent code uses relative | |
2515 | addressesing between segments, the difference between | |
2516 | virtual addresses in memory must match the difference | |
2517 | between virtual addresses in the file. The difference | |
2518 | between the virtual address of any segment in memory and | |
2519 | the corresponding virtual address in the file is thus a | |
2520 | single constant value for any one executable or shared | |
2521 | object in a given process. This difference is the base | |
2522 | address. One use of the base address is to relocate the | |
2523 | memory image of the program during dynamic linking. | |
2524 | ||
2525 | The same language also appears in Edition 4.0 of the System V | |
09919ac2 JK |
2526 | ABI and is left unspecified in some of the earlier editions. |
2527 | ||
2528 | Decide if the objfile needs to be relocated. As indicated above, we will | |
2529 | only be here when execution is stopped. But during attachment PC can be at | |
2530 | arbitrary address therefore regcache_read_pc can be misleading (contrary to | |
2531 | the auxv AT_ENTRY value). Moreover for executable with interpreter section | |
2532 | regcache_read_pc would point to the interpreter and not the main executable. | |
2533 | ||
2534 | So, to summarize, relocations are necessary when the start address obtained | |
2535 | from the executable is different from the address in auxv AT_ENTRY entry. | |
d989b283 | 2536 | |
09919ac2 JK |
2537 | [ The astute reader will note that we also test to make sure that |
2538 | the executable in question has the DYNAMIC flag set. It is my | |
2539 | opinion that this test is unnecessary (undesirable even). It | |
2540 | was added to avoid inadvertent relocation of an executable | |
2541 | whose e_type member in the ELF header is not ET_DYN. There may | |
2542 | be a time in the future when it is desirable to do relocations | |
2543 | on other types of files as well in which case this condition | |
2544 | should either be removed or modified to accomodate the new file | |
2545 | type. - Kevin, Nov 2000. ] */ | |
b8040f19 | 2546 | |
01c30d6e JK |
2547 | static int |
2548 | svr4_exec_displacement (CORE_ADDR *displacementp) | |
b8040f19 | 2549 | { |
41752192 JK |
2550 | /* ENTRY_POINT is a possible function descriptor - before |
2551 | a call to gdbarch_convert_from_func_ptr_addr. */ | |
8f61baf8 | 2552 | CORE_ADDR entry_point, exec_displacement; |
b8040f19 JK |
2553 | |
2554 | if (exec_bfd == NULL) | |
2555 | return 0; | |
2556 | ||
09919ac2 JK |
2557 | /* Therefore for ELF it is ET_EXEC and not ET_DYN. Both shared libraries |
2558 | being executed themselves and PIE (Position Independent Executable) | |
2559 | executables are ET_DYN. */ | |
2560 | ||
2561 | if ((bfd_get_file_flags (exec_bfd) & DYNAMIC) == 0) | |
2562 | return 0; | |
2563 | ||
8b88a78e | 2564 | if (target_auxv_search (current_top_target (), AT_ENTRY, &entry_point) <= 0) |
09919ac2 JK |
2565 | return 0; |
2566 | ||
8f61baf8 | 2567 | exec_displacement = entry_point - bfd_get_start_address (exec_bfd); |
09919ac2 | 2568 | |
8f61baf8 | 2569 | /* Verify the EXEC_DISPLACEMENT candidate complies with the required page |
09919ac2 JK |
2570 | alignment. It is cheaper than the program headers comparison below. */ |
2571 | ||
2572 | if (bfd_get_flavour (exec_bfd) == bfd_target_elf_flavour) | |
2573 | { | |
2574 | const struct elf_backend_data *elf = get_elf_backend_data (exec_bfd); | |
2575 | ||
2576 | /* p_align of PT_LOAD segments does not specify any alignment but | |
2577 | only congruency of addresses: | |
2578 | p_offset % p_align == p_vaddr % p_align | |
2579 | Kernel is free to load the executable with lower alignment. */ | |
2580 | ||
8f61baf8 | 2581 | if ((exec_displacement & (elf->minpagesize - 1)) != 0) |
09919ac2 JK |
2582 | return 0; |
2583 | } | |
2584 | ||
2585 | /* Verify that the auxilliary vector describes the same file as exec_bfd, by | |
2586 | comparing their program headers. If the program headers in the auxilliary | |
2587 | vector do not match the program headers in the executable, then we are | |
2588 | looking at a different file than the one used by the kernel - for | |
2589 | instance, "gdb program" connected to "gdbserver :PORT ld.so program". */ | |
2590 | ||
2591 | if (bfd_get_flavour (exec_bfd) == bfd_target_elf_flavour) | |
2592 | { | |
d1012b8e | 2593 | /* Be optimistic and return 0 only if GDB was able to verify the headers |
09919ac2 | 2594 | really do not match. */ |
0a1e94c7 | 2595 | int arch_size; |
09919ac2 | 2596 | |
17658d46 SM |
2597 | gdb::optional<gdb::byte_vector> phdrs_target |
2598 | = read_program_header (-1, &arch_size, NULL); | |
d1012b8e SM |
2599 | gdb::optional<gdb::byte_vector> phdrs_binary |
2600 | = read_program_headers_from_bfd (exec_bfd); | |
2601 | if (phdrs_target && phdrs_binary) | |
0a1e94c7 | 2602 | { |
f5656ead | 2603 | enum bfd_endian byte_order = gdbarch_byte_order (target_gdbarch ()); |
0a1e94c7 JK |
2604 | |
2605 | /* We are dealing with three different addresses. EXEC_BFD | |
2606 | represents current address in on-disk file. target memory content | |
2607 | may be different from EXEC_BFD as the file may have been prelinked | |
2608 | to a different address after the executable has been loaded. | |
2609 | Moreover the address of placement in target memory can be | |
3e43a32a MS |
2610 | different from what the program headers in target memory say - |
2611 | this is the goal of PIE. | |
0a1e94c7 JK |
2612 | |
2613 | Detected DISPLACEMENT covers both the offsets of PIE placement and | |
2614 | possible new prelink performed after start of the program. Here | |
2615 | relocate BUF and BUF2 just by the EXEC_BFD vs. target memory | |
2616 | content offset for the verification purpose. */ | |
2617 | ||
d1012b8e | 2618 | if (phdrs_target->size () != phdrs_binary->size () |
0a1e94c7 | 2619 | || bfd_get_arch_size (exec_bfd) != arch_size) |
d1012b8e | 2620 | return 0; |
3e43a32a | 2621 | else if (arch_size == 32 |
17658d46 SM |
2622 | && phdrs_target->size () >= sizeof (Elf32_External_Phdr) |
2623 | && phdrs_target->size () % sizeof (Elf32_External_Phdr) == 0) | |
0a1e94c7 JK |
2624 | { |
2625 | Elf_Internal_Ehdr *ehdr2 = elf_tdata (exec_bfd)->elf_header; | |
2626 | Elf_Internal_Phdr *phdr2 = elf_tdata (exec_bfd)->phdr; | |
2627 | CORE_ADDR displacement = 0; | |
2628 | int i; | |
2629 | ||
2630 | /* DISPLACEMENT could be found more easily by the difference of | |
2631 | ehdr2->e_entry. But we haven't read the ehdr yet, and we | |
2632 | already have enough information to compute that displacement | |
2633 | with what we've read. */ | |
2634 | ||
2635 | for (i = 0; i < ehdr2->e_phnum; i++) | |
2636 | if (phdr2[i].p_type == PT_LOAD) | |
2637 | { | |
2638 | Elf32_External_Phdr *phdrp; | |
2639 | gdb_byte *buf_vaddr_p, *buf_paddr_p; | |
2640 | CORE_ADDR vaddr, paddr; | |
2641 | CORE_ADDR displacement_vaddr = 0; | |
2642 | CORE_ADDR displacement_paddr = 0; | |
2643 | ||
17658d46 | 2644 | phdrp = &((Elf32_External_Phdr *) phdrs_target->data ())[i]; |
0a1e94c7 JK |
2645 | buf_vaddr_p = (gdb_byte *) &phdrp->p_vaddr; |
2646 | buf_paddr_p = (gdb_byte *) &phdrp->p_paddr; | |
2647 | ||
2648 | vaddr = extract_unsigned_integer (buf_vaddr_p, 4, | |
2649 | byte_order); | |
2650 | displacement_vaddr = vaddr - phdr2[i].p_vaddr; | |
2651 | ||
2652 | paddr = extract_unsigned_integer (buf_paddr_p, 4, | |
2653 | byte_order); | |
2654 | displacement_paddr = paddr - phdr2[i].p_paddr; | |
2655 | ||
2656 | if (displacement_vaddr == displacement_paddr) | |
2657 | displacement = displacement_vaddr; | |
2658 | ||
2659 | break; | |
2660 | } | |
2661 | ||
17658d46 SM |
2662 | /* Now compare program headers from the target and the binary |
2663 | with optional DISPLACEMENT. */ | |
0a1e94c7 | 2664 | |
17658d46 SM |
2665 | for (i = 0; |
2666 | i < phdrs_target->size () / sizeof (Elf32_External_Phdr); | |
2667 | i++) | |
0a1e94c7 JK |
2668 | { |
2669 | Elf32_External_Phdr *phdrp; | |
2670 | Elf32_External_Phdr *phdr2p; | |
2671 | gdb_byte *buf_vaddr_p, *buf_paddr_p; | |
2672 | CORE_ADDR vaddr, paddr; | |
43b8e241 | 2673 | asection *plt2_asect; |
0a1e94c7 | 2674 | |
17658d46 | 2675 | phdrp = &((Elf32_External_Phdr *) phdrs_target->data ())[i]; |
0a1e94c7 JK |
2676 | buf_vaddr_p = (gdb_byte *) &phdrp->p_vaddr; |
2677 | buf_paddr_p = (gdb_byte *) &phdrp->p_paddr; | |
d1012b8e | 2678 | phdr2p = &((Elf32_External_Phdr *) phdrs_binary->data ())[i]; |
0a1e94c7 JK |
2679 | |
2680 | /* PT_GNU_STACK is an exception by being never relocated by | |
2681 | prelink as its addresses are always zero. */ | |
2682 | ||
2683 | if (memcmp (phdrp, phdr2p, sizeof (*phdrp)) == 0) | |
2684 | continue; | |
2685 | ||
2686 | /* Check also other adjustment combinations - PR 11786. */ | |
2687 | ||
3e43a32a MS |
2688 | vaddr = extract_unsigned_integer (buf_vaddr_p, 4, |
2689 | byte_order); | |
0a1e94c7 JK |
2690 | vaddr -= displacement; |
2691 | store_unsigned_integer (buf_vaddr_p, 4, byte_order, vaddr); | |
2692 | ||
3e43a32a MS |
2693 | paddr = extract_unsigned_integer (buf_paddr_p, 4, |
2694 | byte_order); | |
0a1e94c7 JK |
2695 | paddr -= displacement; |
2696 | store_unsigned_integer (buf_paddr_p, 4, byte_order, paddr); | |
2697 | ||
2698 | if (memcmp (phdrp, phdr2p, sizeof (*phdrp)) == 0) | |
2699 | continue; | |
2700 | ||
204b5331 DE |
2701 | /* Strip modifies the flags and alignment of PT_GNU_RELRO. |
2702 | CentOS-5 has problems with filesz, memsz as well. | |
be2d111a | 2703 | Strip also modifies memsz of PT_TLS. |
204b5331 | 2704 | See PR 11786. */ |
c44deb73 SM |
2705 | if (phdr2[i].p_type == PT_GNU_RELRO |
2706 | || phdr2[i].p_type == PT_TLS) | |
204b5331 DE |
2707 | { |
2708 | Elf32_External_Phdr tmp_phdr = *phdrp; | |
2709 | Elf32_External_Phdr tmp_phdr2 = *phdr2p; | |
2710 | ||
2711 | memset (tmp_phdr.p_filesz, 0, 4); | |
2712 | memset (tmp_phdr.p_memsz, 0, 4); | |
2713 | memset (tmp_phdr.p_flags, 0, 4); | |
2714 | memset (tmp_phdr.p_align, 0, 4); | |
2715 | memset (tmp_phdr2.p_filesz, 0, 4); | |
2716 | memset (tmp_phdr2.p_memsz, 0, 4); | |
2717 | memset (tmp_phdr2.p_flags, 0, 4); | |
2718 | memset (tmp_phdr2.p_align, 0, 4); | |
2719 | ||
2720 | if (memcmp (&tmp_phdr, &tmp_phdr2, sizeof (tmp_phdr)) | |
2721 | == 0) | |
2722 | continue; | |
2723 | } | |
2724 | ||
43b8e241 JK |
2725 | /* prelink can convert .plt SHT_NOBITS to SHT_PROGBITS. */ |
2726 | plt2_asect = bfd_get_section_by_name (exec_bfd, ".plt"); | |
2727 | if (plt2_asect) | |
2728 | { | |
2729 | int content2; | |
2730 | gdb_byte *buf_filesz_p = (gdb_byte *) &phdrp->p_filesz; | |
2731 | CORE_ADDR filesz; | |
2732 | ||
2733 | content2 = (bfd_get_section_flags (exec_bfd, plt2_asect) | |
2734 | & SEC_HAS_CONTENTS) != 0; | |
2735 | ||
2736 | filesz = extract_unsigned_integer (buf_filesz_p, 4, | |
2737 | byte_order); | |
2738 | ||
2739 | /* PLT2_ASECT is from on-disk file (exec_bfd) while | |
2740 | FILESZ is from the in-memory image. */ | |
2741 | if (content2) | |
2742 | filesz += bfd_get_section_size (plt2_asect); | |
2743 | else | |
2744 | filesz -= bfd_get_section_size (plt2_asect); | |
2745 | ||
2746 | store_unsigned_integer (buf_filesz_p, 4, byte_order, | |
2747 | filesz); | |
2748 | ||
2749 | if (memcmp (phdrp, phdr2p, sizeof (*phdrp)) == 0) | |
2750 | continue; | |
2751 | } | |
2752 | ||
d1012b8e | 2753 | return 0; |
0a1e94c7 JK |
2754 | } |
2755 | } | |
3e43a32a | 2756 | else if (arch_size == 64 |
17658d46 SM |
2757 | && phdrs_target->size () >= sizeof (Elf64_External_Phdr) |
2758 | && phdrs_target->size () % sizeof (Elf64_External_Phdr) == 0) | |
0a1e94c7 JK |
2759 | { |
2760 | Elf_Internal_Ehdr *ehdr2 = elf_tdata (exec_bfd)->elf_header; | |
2761 | Elf_Internal_Phdr *phdr2 = elf_tdata (exec_bfd)->phdr; | |
2762 | CORE_ADDR displacement = 0; | |
2763 | int i; | |
2764 | ||
2765 | /* DISPLACEMENT could be found more easily by the difference of | |
2766 | ehdr2->e_entry. But we haven't read the ehdr yet, and we | |
2767 | already have enough information to compute that displacement | |
2768 | with what we've read. */ | |
2769 | ||
2770 | for (i = 0; i < ehdr2->e_phnum; i++) | |
2771 | if (phdr2[i].p_type == PT_LOAD) | |
2772 | { | |
2773 | Elf64_External_Phdr *phdrp; | |
2774 | gdb_byte *buf_vaddr_p, *buf_paddr_p; | |
2775 | CORE_ADDR vaddr, paddr; | |
2776 | CORE_ADDR displacement_vaddr = 0; | |
2777 | CORE_ADDR displacement_paddr = 0; | |
2778 | ||
17658d46 | 2779 | phdrp = &((Elf64_External_Phdr *) phdrs_target->data ())[i]; |
0a1e94c7 JK |
2780 | buf_vaddr_p = (gdb_byte *) &phdrp->p_vaddr; |
2781 | buf_paddr_p = (gdb_byte *) &phdrp->p_paddr; | |
2782 | ||
2783 | vaddr = extract_unsigned_integer (buf_vaddr_p, 8, | |
2784 | byte_order); | |
2785 | displacement_vaddr = vaddr - phdr2[i].p_vaddr; | |
2786 | ||
2787 | paddr = extract_unsigned_integer (buf_paddr_p, 8, | |
2788 | byte_order); | |
2789 | displacement_paddr = paddr - phdr2[i].p_paddr; | |
2790 | ||
2791 | if (displacement_vaddr == displacement_paddr) | |
2792 | displacement = displacement_vaddr; | |
2793 | ||
2794 | break; | |
2795 | } | |
2796 | ||
2797 | /* Now compare BUF and BUF2 with optional DISPLACEMENT. */ | |
2798 | ||
17658d46 SM |
2799 | for (i = 0; |
2800 | i < phdrs_target->size () / sizeof (Elf64_External_Phdr); | |
2801 | i++) | |
0a1e94c7 JK |
2802 | { |
2803 | Elf64_External_Phdr *phdrp; | |
2804 | Elf64_External_Phdr *phdr2p; | |
2805 | gdb_byte *buf_vaddr_p, *buf_paddr_p; | |
2806 | CORE_ADDR vaddr, paddr; | |
43b8e241 | 2807 | asection *plt2_asect; |
0a1e94c7 | 2808 | |
17658d46 | 2809 | phdrp = &((Elf64_External_Phdr *) phdrs_target->data ())[i]; |
0a1e94c7 JK |
2810 | buf_vaddr_p = (gdb_byte *) &phdrp->p_vaddr; |
2811 | buf_paddr_p = (gdb_byte *) &phdrp->p_paddr; | |
d1012b8e | 2812 | phdr2p = &((Elf64_External_Phdr *) phdrs_binary->data ())[i]; |
0a1e94c7 JK |
2813 | |
2814 | /* PT_GNU_STACK is an exception by being never relocated by | |
2815 | prelink as its addresses are always zero. */ | |
2816 | ||
2817 | if (memcmp (phdrp, phdr2p, sizeof (*phdrp)) == 0) | |
2818 | continue; | |
2819 | ||
2820 | /* Check also other adjustment combinations - PR 11786. */ | |
2821 | ||
3e43a32a MS |
2822 | vaddr = extract_unsigned_integer (buf_vaddr_p, 8, |
2823 | byte_order); | |
0a1e94c7 JK |
2824 | vaddr -= displacement; |
2825 | store_unsigned_integer (buf_vaddr_p, 8, byte_order, vaddr); | |
2826 | ||
3e43a32a MS |
2827 | paddr = extract_unsigned_integer (buf_paddr_p, 8, |
2828 | byte_order); | |
0a1e94c7 JK |
2829 | paddr -= displacement; |
2830 | store_unsigned_integer (buf_paddr_p, 8, byte_order, paddr); | |
2831 | ||
2832 | if (memcmp (phdrp, phdr2p, sizeof (*phdrp)) == 0) | |
2833 | continue; | |
2834 | ||
204b5331 DE |
2835 | /* Strip modifies the flags and alignment of PT_GNU_RELRO. |
2836 | CentOS-5 has problems with filesz, memsz as well. | |
be2d111a | 2837 | Strip also modifies memsz of PT_TLS. |
204b5331 | 2838 | See PR 11786. */ |
c44deb73 SM |
2839 | if (phdr2[i].p_type == PT_GNU_RELRO |
2840 | || phdr2[i].p_type == PT_TLS) | |
204b5331 DE |
2841 | { |
2842 | Elf64_External_Phdr tmp_phdr = *phdrp; | |
2843 | Elf64_External_Phdr tmp_phdr2 = *phdr2p; | |
2844 | ||
2845 | memset (tmp_phdr.p_filesz, 0, 8); | |
2846 | memset (tmp_phdr.p_memsz, 0, 8); | |
2847 | memset (tmp_phdr.p_flags, 0, 4); | |
2848 | memset (tmp_phdr.p_align, 0, 8); | |
2849 | memset (tmp_phdr2.p_filesz, 0, 8); | |
2850 | memset (tmp_phdr2.p_memsz, 0, 8); | |
2851 | memset (tmp_phdr2.p_flags, 0, 4); | |
2852 | memset (tmp_phdr2.p_align, 0, 8); | |
2853 | ||
2854 | if (memcmp (&tmp_phdr, &tmp_phdr2, sizeof (tmp_phdr)) | |
2855 | == 0) | |
2856 | continue; | |
2857 | } | |
2858 | ||
43b8e241 JK |
2859 | /* prelink can convert .plt SHT_NOBITS to SHT_PROGBITS. */ |
2860 | plt2_asect = bfd_get_section_by_name (exec_bfd, ".plt"); | |
2861 | if (plt2_asect) | |
2862 | { | |
2863 | int content2; | |
2864 | gdb_byte *buf_filesz_p = (gdb_byte *) &phdrp->p_filesz; | |
2865 | CORE_ADDR filesz; | |
2866 | ||
2867 | content2 = (bfd_get_section_flags (exec_bfd, plt2_asect) | |
2868 | & SEC_HAS_CONTENTS) != 0; | |
2869 | ||
2870 | filesz = extract_unsigned_integer (buf_filesz_p, 8, | |
2871 | byte_order); | |
2872 | ||
2873 | /* PLT2_ASECT is from on-disk file (exec_bfd) while | |
2874 | FILESZ is from the in-memory image. */ | |
2875 | if (content2) | |
2876 | filesz += bfd_get_section_size (plt2_asect); | |
2877 | else | |
2878 | filesz -= bfd_get_section_size (plt2_asect); | |
2879 | ||
2880 | store_unsigned_integer (buf_filesz_p, 8, byte_order, | |
2881 | filesz); | |
2882 | ||
2883 | if (memcmp (phdrp, phdr2p, sizeof (*phdrp)) == 0) | |
2884 | continue; | |
2885 | } | |
2886 | ||
d1012b8e | 2887 | return 0; |
0a1e94c7 JK |
2888 | } |
2889 | } | |
2890 | else | |
d1012b8e | 2891 | return 0; |
0a1e94c7 | 2892 | } |
09919ac2 | 2893 | } |
b8040f19 | 2894 | |
ccf26247 JK |
2895 | if (info_verbose) |
2896 | { | |
2897 | /* It can be printed repeatedly as there is no easy way to check | |
2898 | the executable symbols/file has been already relocated to | |
2899 | displacement. */ | |
2900 | ||
2901 | printf_unfiltered (_("Using PIE (Position Independent Executable) " | |
2902 | "displacement %s for \"%s\".\n"), | |
8f61baf8 | 2903 | paddress (target_gdbarch (), exec_displacement), |
ccf26247 JK |
2904 | bfd_get_filename (exec_bfd)); |
2905 | } | |
2906 | ||
8f61baf8 | 2907 | *displacementp = exec_displacement; |
01c30d6e | 2908 | return 1; |
b8040f19 JK |
2909 | } |
2910 | ||
2911 | /* Relocate the main executable. This function should be called upon | |
c378eb4e | 2912 | stopping the inferior process at the entry point to the program. |
b8040f19 JK |
2913 | The entry point from BFD is compared to the AT_ENTRY of AUXV and if they are |
2914 | different, the main executable is relocated by the proper amount. */ | |
2915 | ||
2916 | static void | |
2917 | svr4_relocate_main_executable (void) | |
2918 | { | |
01c30d6e JK |
2919 | CORE_ADDR displacement; |
2920 | ||
4e5799b6 JK |
2921 | /* If we are re-running this executable, SYMFILE_OBJFILE->SECTION_OFFSETS |
2922 | probably contains the offsets computed using the PIE displacement | |
2923 | from the previous run, which of course are irrelevant for this run. | |
2924 | So we need to determine the new PIE displacement and recompute the | |
2925 | section offsets accordingly, even if SYMFILE_OBJFILE->SECTION_OFFSETS | |
2926 | already contains pre-computed offsets. | |
01c30d6e | 2927 | |
4e5799b6 | 2928 | If we cannot compute the PIE displacement, either: |
01c30d6e | 2929 | |
4e5799b6 JK |
2930 | - The executable is not PIE. |
2931 | ||
2932 | - SYMFILE_OBJFILE does not match the executable started in the target. | |
2933 | This can happen for main executable symbols loaded at the host while | |
2934 | `ld.so --ld-args main-executable' is loaded in the target. | |
2935 | ||
2936 | Then we leave the section offsets untouched and use them as is for | |
2937 | this run. Either: | |
2938 | ||
2939 | - These section offsets were properly reset earlier, and thus | |
2940 | already contain the correct values. This can happen for instance | |
2941 | when reconnecting via the remote protocol to a target that supports | |
2942 | the `qOffsets' packet. | |
2943 | ||
2944 | - The section offsets were not reset earlier, and the best we can | |
c378eb4e | 2945 | hope is that the old offsets are still applicable to the new run. */ |
01c30d6e JK |
2946 | |
2947 | if (! svr4_exec_displacement (&displacement)) | |
2948 | return; | |
b8040f19 | 2949 | |
01c30d6e JK |
2950 | /* Even DISPLACEMENT 0 is a valid new difference of in-memory vs. in-file |
2951 | addresses. */ | |
b8040f19 JK |
2952 | |
2953 | if (symfile_objfile) | |
e2a44558 | 2954 | { |
e2a44558 | 2955 | struct section_offsets *new_offsets; |
b8040f19 | 2956 | int i; |
e2a44558 | 2957 | |
224c3ddb SM |
2958 | new_offsets = XALLOCAVEC (struct section_offsets, |
2959 | symfile_objfile->num_sections); | |
e2a44558 | 2960 | |
b8040f19 JK |
2961 | for (i = 0; i < symfile_objfile->num_sections; i++) |
2962 | new_offsets->offsets[i] = displacement; | |
e2a44558 | 2963 | |
b8040f19 | 2964 | objfile_relocate (symfile_objfile, new_offsets); |
e2a44558 | 2965 | } |
51bee8e9 JK |
2966 | else if (exec_bfd) |
2967 | { | |
2968 | asection *asect; | |
2969 | ||
2970 | for (asect = exec_bfd->sections; asect != NULL; asect = asect->next) | |
2971 | exec_set_section_address (bfd_get_filename (exec_bfd), asect->index, | |
2972 | (bfd_section_vma (exec_bfd, asect) | |
2973 | + displacement)); | |
2974 | } | |
e2a44558 KB |
2975 | } |
2976 | ||
7f86f058 | 2977 | /* Implement the "create_inferior_hook" target_solib_ops method. |
13437d4b KB |
2978 | |
2979 | For SVR4 executables, this first instruction is either the first | |
2980 | instruction in the dynamic linker (for dynamically linked | |
2981 | executables) or the instruction at "start" for statically linked | |
2982 | executables. For dynamically linked executables, the system | |
2983 | first exec's /lib/libc.so.N, which contains the dynamic linker, | |
2984 | and starts it running. The dynamic linker maps in any needed | |
2985 | shared libraries, maps in the actual user executable, and then | |
2986 | jumps to "start" in the user executable. | |
2987 | ||
7f86f058 PA |
2988 | We can arrange to cooperate with the dynamic linker to discover the |
2989 | names of shared libraries that are dynamically linked, and the base | |
2990 | addresses to which they are linked. | |
13437d4b KB |
2991 | |
2992 | This function is responsible for discovering those names and | |
2993 | addresses, and saving sufficient information about them to allow | |
d2e5c99a | 2994 | their symbols to be read at a later time. */ |
13437d4b | 2995 | |
e2a44558 | 2996 | static void |
268a4a75 | 2997 | svr4_solib_create_inferior_hook (int from_tty) |
13437d4b | 2998 | { |
1a816a87 PA |
2999 | struct svr4_info *info; |
3000 | ||
d70cc3ba | 3001 | info = get_svr4_info (current_program_space); |
2020b7ab | 3002 | |
f9e14852 GB |
3003 | /* Clear the probes-based interface's state. */ |
3004 | free_probes_table (info); | |
3005 | free_solib_list (info); | |
3006 | ||
e2a44558 | 3007 | /* Relocate the main executable if necessary. */ |
86e4bafc | 3008 | svr4_relocate_main_executable (); |
e2a44558 | 3009 | |
c91c8c16 PA |
3010 | /* No point setting a breakpoint in the dynamic linker if we can't |
3011 | hit it (e.g., a core file, or a trace file). */ | |
3012 | if (!target_has_execution) | |
3013 | return; | |
3014 | ||
d5a921c9 | 3015 | if (!svr4_have_link_map_offsets ()) |
513f5903 | 3016 | return; |
d5a921c9 | 3017 | |
268a4a75 | 3018 | if (!enable_break (info, from_tty)) |
542c95c2 | 3019 | return; |
13437d4b KB |
3020 | } |
3021 | ||
3022 | static void | |
3023 | svr4_clear_solib (void) | |
3024 | { | |
6c95b8df PA |
3025 | struct svr4_info *info; |
3026 | ||
d70cc3ba | 3027 | info = get_svr4_info (current_program_space); |
6c95b8df PA |
3028 | info->debug_base = 0; |
3029 | info->debug_loader_offset_p = 0; | |
3030 | info->debug_loader_offset = 0; | |
3031 | xfree (info->debug_loader_name); | |
3032 | info->debug_loader_name = NULL; | |
13437d4b KB |
3033 | } |
3034 | ||
6bb7be43 JB |
3035 | /* Clear any bits of ADDR that wouldn't fit in a target-format |
3036 | data pointer. "Data pointer" here refers to whatever sort of | |
3037 | address the dynamic linker uses to manage its sections. At the | |
3038 | moment, we don't support shared libraries on any processors where | |
3039 | code and data pointers are different sizes. | |
3040 | ||
3041 | This isn't really the right solution. What we really need here is | |
3042 | a way to do arithmetic on CORE_ADDR values that respects the | |
3043 | natural pointer/address correspondence. (For example, on the MIPS, | |
3044 | converting a 32-bit pointer to a 64-bit CORE_ADDR requires you to | |
3045 | sign-extend the value. There, simply truncating the bits above | |
819844ad | 3046 | gdbarch_ptr_bit, as we do below, is no good.) This should probably |
6bb7be43 JB |
3047 | be a new gdbarch method or something. */ |
3048 | static CORE_ADDR | |
3049 | svr4_truncate_ptr (CORE_ADDR addr) | |
3050 | { | |
f5656ead | 3051 | if (gdbarch_ptr_bit (target_gdbarch ()) == sizeof (CORE_ADDR) * 8) |
6bb7be43 JB |
3052 | /* We don't need to truncate anything, and the bit twiddling below |
3053 | will fail due to overflow problems. */ | |
3054 | return addr; | |
3055 | else | |
f5656ead | 3056 | return addr & (((CORE_ADDR) 1 << gdbarch_ptr_bit (target_gdbarch ())) - 1); |
6bb7be43 JB |
3057 | } |
3058 | ||
3059 | ||
749499cb KB |
3060 | static void |
3061 | svr4_relocate_section_addresses (struct so_list *so, | |
0542c86d | 3062 | struct target_section *sec) |
749499cb | 3063 | { |
2b2848e2 DE |
3064 | bfd *abfd = sec->the_bfd_section->owner; |
3065 | ||
3066 | sec->addr = svr4_truncate_ptr (sec->addr + lm_addr_check (so, abfd)); | |
3067 | sec->endaddr = svr4_truncate_ptr (sec->endaddr + lm_addr_check (so, abfd)); | |
749499cb | 3068 | } |
4b188b9f | 3069 | \f |
749499cb | 3070 | |
4b188b9f | 3071 | /* Architecture-specific operations. */ |
6bb7be43 | 3072 | |
4b188b9f MK |
3073 | /* Per-architecture data key. */ |
3074 | static struct gdbarch_data *solib_svr4_data; | |
e5e2b9ff | 3075 | |
4b188b9f | 3076 | struct solib_svr4_ops |
e5e2b9ff | 3077 | { |
4b188b9f MK |
3078 | /* Return a description of the layout of `struct link_map'. */ |
3079 | struct link_map_offsets *(*fetch_link_map_offsets)(void); | |
3080 | }; | |
e5e2b9ff | 3081 | |
4b188b9f | 3082 | /* Return a default for the architecture-specific operations. */ |
e5e2b9ff | 3083 | |
4b188b9f MK |
3084 | static void * |
3085 | solib_svr4_init (struct obstack *obstack) | |
e5e2b9ff | 3086 | { |
4b188b9f | 3087 | struct solib_svr4_ops *ops; |
e5e2b9ff | 3088 | |
4b188b9f | 3089 | ops = OBSTACK_ZALLOC (obstack, struct solib_svr4_ops); |
8d005789 | 3090 | ops->fetch_link_map_offsets = NULL; |
4b188b9f | 3091 | return ops; |
e5e2b9ff KB |
3092 | } |
3093 | ||
4b188b9f | 3094 | /* Set the architecture-specific `struct link_map_offsets' fetcher for |
7e3cb44c | 3095 | GDBARCH to FLMO. Also, install SVR4 solib_ops into GDBARCH. */ |
1c4dcb57 | 3096 | |
21479ded | 3097 | void |
e5e2b9ff KB |
3098 | set_solib_svr4_fetch_link_map_offsets (struct gdbarch *gdbarch, |
3099 | struct link_map_offsets *(*flmo) (void)) | |
21479ded | 3100 | { |
19ba03f4 SM |
3101 | struct solib_svr4_ops *ops |
3102 | = (struct solib_svr4_ops *) gdbarch_data (gdbarch, solib_svr4_data); | |
4b188b9f MK |
3103 | |
3104 | ops->fetch_link_map_offsets = flmo; | |
7e3cb44c UW |
3105 | |
3106 | set_solib_ops (gdbarch, &svr4_so_ops); | |
21479ded KB |
3107 | } |
3108 | ||
4b188b9f MK |
3109 | /* Fetch a link_map_offsets structure using the architecture-specific |
3110 | `struct link_map_offsets' fetcher. */ | |
1c4dcb57 | 3111 | |
4b188b9f MK |
3112 | static struct link_map_offsets * |
3113 | svr4_fetch_link_map_offsets (void) | |
21479ded | 3114 | { |
19ba03f4 SM |
3115 | struct solib_svr4_ops *ops |
3116 | = (struct solib_svr4_ops *) gdbarch_data (target_gdbarch (), | |
3117 | solib_svr4_data); | |
4b188b9f MK |
3118 | |
3119 | gdb_assert (ops->fetch_link_map_offsets); | |
3120 | return ops->fetch_link_map_offsets (); | |
21479ded KB |
3121 | } |
3122 | ||
4b188b9f MK |
3123 | /* Return 1 if a link map offset fetcher has been defined, 0 otherwise. */ |
3124 | ||
3125 | static int | |
3126 | svr4_have_link_map_offsets (void) | |
3127 | { | |
19ba03f4 SM |
3128 | struct solib_svr4_ops *ops |
3129 | = (struct solib_svr4_ops *) gdbarch_data (target_gdbarch (), | |
3130 | solib_svr4_data); | |
433759f7 | 3131 | |
4b188b9f MK |
3132 | return (ops->fetch_link_map_offsets != NULL); |
3133 | } | |
3134 | \f | |
3135 | ||
e4bbbda8 MK |
3136 | /* Most OS'es that have SVR4-style ELF dynamic libraries define a |
3137 | `struct r_debug' and a `struct link_map' that are binary compatible | |
3138 | with the origional SVR4 implementation. */ | |
3139 | ||
3140 | /* Fetch (and possibly build) an appropriate `struct link_map_offsets' | |
3141 | for an ILP32 SVR4 system. */ | |
d989b283 | 3142 | |
e4bbbda8 MK |
3143 | struct link_map_offsets * |
3144 | svr4_ilp32_fetch_link_map_offsets (void) | |
3145 | { | |
3146 | static struct link_map_offsets lmo; | |
3147 | static struct link_map_offsets *lmp = NULL; | |
3148 | ||
3149 | if (lmp == NULL) | |
3150 | { | |
3151 | lmp = &lmo; | |
3152 | ||
e4cd0d6a MK |
3153 | lmo.r_version_offset = 0; |
3154 | lmo.r_version_size = 4; | |
e4bbbda8 | 3155 | lmo.r_map_offset = 4; |
7cd25cfc | 3156 | lmo.r_brk_offset = 8; |
e4cd0d6a | 3157 | lmo.r_ldsomap_offset = 20; |
e4bbbda8 MK |
3158 | |
3159 | /* Everything we need is in the first 20 bytes. */ | |
3160 | lmo.link_map_size = 20; | |
3161 | lmo.l_addr_offset = 0; | |
e4bbbda8 | 3162 | lmo.l_name_offset = 4; |
cc10cae3 | 3163 | lmo.l_ld_offset = 8; |
e4bbbda8 | 3164 | lmo.l_next_offset = 12; |
e4bbbda8 | 3165 | lmo.l_prev_offset = 16; |
e4bbbda8 MK |
3166 | } |
3167 | ||
3168 | return lmp; | |
3169 | } | |
3170 | ||
3171 | /* Fetch (and possibly build) an appropriate `struct link_map_offsets' | |
3172 | for an LP64 SVR4 system. */ | |
d989b283 | 3173 | |
e4bbbda8 MK |
3174 | struct link_map_offsets * |
3175 | svr4_lp64_fetch_link_map_offsets (void) | |
3176 | { | |
3177 | static struct link_map_offsets lmo; | |
3178 | static struct link_map_offsets *lmp = NULL; | |
3179 | ||
3180 | if (lmp == NULL) | |
3181 | { | |
3182 | lmp = &lmo; | |
3183 | ||
e4cd0d6a MK |
3184 | lmo.r_version_offset = 0; |
3185 | lmo.r_version_size = 4; | |
e4bbbda8 | 3186 | lmo.r_map_offset = 8; |
7cd25cfc | 3187 | lmo.r_brk_offset = 16; |
e4cd0d6a | 3188 | lmo.r_ldsomap_offset = 40; |
e4bbbda8 MK |
3189 | |
3190 | /* Everything we need is in the first 40 bytes. */ | |
3191 | lmo.link_map_size = 40; | |
3192 | lmo.l_addr_offset = 0; | |
e4bbbda8 | 3193 | lmo.l_name_offset = 8; |
cc10cae3 | 3194 | lmo.l_ld_offset = 16; |
e4bbbda8 | 3195 | lmo.l_next_offset = 24; |
e4bbbda8 | 3196 | lmo.l_prev_offset = 32; |
e4bbbda8 MK |
3197 | } |
3198 | ||
3199 | return lmp; | |
3200 | } | |
3201 | \f | |
3202 | ||
7d522c90 | 3203 | struct target_so_ops svr4_so_ops; |
13437d4b | 3204 | |
c378eb4e | 3205 | /* Lookup global symbol for ELF DSOs linked with -Bsymbolic. Those DSOs have a |
3a40aaa0 UW |
3206 | different rule for symbol lookup. The lookup begins here in the DSO, not in |
3207 | the main executable. */ | |
3208 | ||
d12307c1 | 3209 | static struct block_symbol |
efad9b6a | 3210 | elf_lookup_lib_symbol (struct objfile *objfile, |
3a40aaa0 | 3211 | const char *name, |
21b556f4 | 3212 | const domain_enum domain) |
3a40aaa0 | 3213 | { |
61f0d762 JK |
3214 | bfd *abfd; |
3215 | ||
3216 | if (objfile == symfile_objfile) | |
3217 | abfd = exec_bfd; | |
3218 | else | |
3219 | { | |
3220 | /* OBJFILE should have been passed as the non-debug one. */ | |
3221 | gdb_assert (objfile->separate_debug_objfile_backlink == NULL); | |
3222 | ||
3223 | abfd = objfile->obfd; | |
3224 | } | |
3225 | ||
a738da3a | 3226 | if (abfd == NULL || scan_dyntag (DT_SYMBOLIC, abfd, NULL, NULL) != 1) |
6640a367 | 3227 | return {}; |
3a40aaa0 | 3228 | |
94af9270 | 3229 | return lookup_global_symbol_from_objfile (objfile, name, domain); |
3a40aaa0 UW |
3230 | } |
3231 | ||
13437d4b KB |
3232 | void |
3233 | _initialize_svr4_solib (void) | |
3234 | { | |
4b188b9f MK |
3235 | solib_svr4_data = gdbarch_data_register_pre_init (solib_svr4_init); |
3236 | ||
749499cb | 3237 | svr4_so_ops.relocate_section_addresses = svr4_relocate_section_addresses; |
13437d4b | 3238 | svr4_so_ops.free_so = svr4_free_so; |
0892cb63 | 3239 | svr4_so_ops.clear_so = svr4_clear_so; |
13437d4b KB |
3240 | svr4_so_ops.clear_solib = svr4_clear_solib; |
3241 | svr4_so_ops.solib_create_inferior_hook = svr4_solib_create_inferior_hook; | |
13437d4b KB |
3242 | svr4_so_ops.current_sos = svr4_current_sos; |
3243 | svr4_so_ops.open_symbol_file_object = open_symbol_file_object; | |
d7fa2ae2 | 3244 | svr4_so_ops.in_dynsym_resolve_code = svr4_in_dynsym_resolve_code; |
831a0c44 | 3245 | svr4_so_ops.bfd_open = solib_bfd_open; |
3a40aaa0 | 3246 | svr4_so_ops.lookup_lib_global_symbol = elf_lookup_lib_symbol; |
a7c02bc8 | 3247 | svr4_so_ops.same = svr4_same; |
de18c1d8 | 3248 | svr4_so_ops.keep_data_in_core = svr4_keep_data_in_core; |
f9e14852 GB |
3249 | svr4_so_ops.update_breakpoints = svr4_update_solib_event_breakpoints; |
3250 | svr4_so_ops.handle_event = svr4_handle_solib_event; | |
7905fc35 PA |
3251 | |
3252 | gdb::observers::free_objfile.attach (svr4_free_objfile_observer); | |
13437d4b | 3253 | } |