1 /* Intel 80386/80486-specific support for 32-bit ELF
2 Copyright 1993, 1994, 1995, 1996, 1997, 1998, 1999, 2000, 2001, 2002,
3 2003, 2004 Free Software Foundation, Inc.
4
5 This file is part of BFD, the Binary File Descriptor library.
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
9 the Free Software Foundation; either version 2 of the License, or
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
18 along with this program; if not, write to the Free Software
19 Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. */
20
21 #include "bfd.h"
22 #include "sysdep.h"
23 #include "bfdlink.h"
24 #include "libbfd.h"
25 #include "elf-bfd.h"
26
27 /* 386 uses REL relocations instead of RELA. */
28 #define USE_REL 1
29
30 #include "elf/i386.h"
31
32 static reloc_howto_type elf_howto_table[]=
33 {
34 HOWTO(R_386_NONE, 0, 0, 0, FALSE, 0, complain_overflow_bitfield,
35 bfd_elf_generic_reloc, "R_386_NONE",
36 TRUE, 0x00000000, 0x00000000, FALSE),
37 HOWTO(R_386_32, 0, 2, 32, FALSE, 0, complain_overflow_bitfield,
38 bfd_elf_generic_reloc, "R_386_32",
39 TRUE, 0xffffffff, 0xffffffff, FALSE),
40 HOWTO(R_386_PC32, 0, 2, 32, TRUE, 0, complain_overflow_bitfield,
41 bfd_elf_generic_reloc, "R_386_PC32",
42 TRUE, 0xffffffff, 0xffffffff, TRUE),
43 HOWTO(R_386_GOT32, 0, 2, 32, FALSE, 0, complain_overflow_bitfield,
44 bfd_elf_generic_reloc, "R_386_GOT32",
45 TRUE, 0xffffffff, 0xffffffff, FALSE),
46 HOWTO(R_386_PLT32, 0, 2, 32, TRUE, 0, complain_overflow_bitfield,
47 bfd_elf_generic_reloc, "R_386_PLT32",
48 TRUE, 0xffffffff, 0xffffffff, TRUE),
49 HOWTO(R_386_COPY, 0, 2, 32, FALSE, 0, complain_overflow_bitfield,
50 bfd_elf_generic_reloc, "R_386_COPY",
51 TRUE, 0xffffffff, 0xffffffff, FALSE),
52 HOWTO(R_386_GLOB_DAT, 0, 2, 32, FALSE, 0, complain_overflow_bitfield,
53 bfd_elf_generic_reloc, "R_386_GLOB_DAT",
54 TRUE, 0xffffffff, 0xffffffff, FALSE),
55 HOWTO(R_386_JUMP_SLOT, 0, 2, 32, FALSE, 0, complain_overflow_bitfield,
56 bfd_elf_generic_reloc, "R_386_JUMP_SLOT",
57 TRUE, 0xffffffff, 0xffffffff, FALSE),
58 HOWTO(R_386_RELATIVE, 0, 2, 32, FALSE, 0, complain_overflow_bitfield,
59 bfd_elf_generic_reloc, "R_386_RELATIVE",
60 TRUE, 0xffffffff, 0xffffffff, FALSE),
61 HOWTO(R_386_GOTOFF, 0, 2, 32, FALSE, 0, complain_overflow_bitfield,
62 bfd_elf_generic_reloc, "R_386_GOTOFF",
63 TRUE, 0xffffffff, 0xffffffff, FALSE),
64 HOWTO(R_386_GOTPC, 0, 2, 32, TRUE, 0, complain_overflow_bitfield,
65 bfd_elf_generic_reloc, "R_386_GOTPC",
66 TRUE, 0xffffffff, 0xffffffff, TRUE),
67
68 /* We have a gap in the reloc numbers here.
69 R_386_standard counts the number up to this point, and
70 R_386_ext_offset is the value to subtract from a reloc type of
71 R_386_16 thru R_386_PC8 to form an index into this table. */
72 #define R_386_standard (R_386_GOTPC + 1)
73 #define R_386_ext_offset (R_386_TLS_TPOFF - R_386_standard)
74
75 /* These relocs are a GNU extension. */
76 HOWTO(R_386_TLS_TPOFF, 0, 2, 32, FALSE, 0, complain_overflow_bitfield,
77 bfd_elf_generic_reloc, "R_386_TLS_TPOFF",
78 TRUE, 0xffffffff, 0xffffffff, FALSE),
79 HOWTO(R_386_TLS_IE, 0, 2, 32, FALSE, 0, complain_overflow_bitfield,
80 bfd_elf_generic_reloc, "R_386_TLS_IE",
81 TRUE, 0xffffffff, 0xffffffff, FALSE),
82 HOWTO(R_386_TLS_GOTIE, 0, 2, 32, FALSE, 0, complain_overflow_bitfield,
83 bfd_elf_generic_reloc, "R_386_TLS_GOTIE",
84 TRUE, 0xffffffff, 0xffffffff, FALSE),
85 HOWTO(R_386_TLS_LE, 0, 2, 32, FALSE, 0, complain_overflow_bitfield,
86 bfd_elf_generic_reloc, "R_386_TLS_LE",
87 TRUE, 0xffffffff, 0xffffffff, FALSE),
88 HOWTO(R_386_TLS_GD, 0, 2, 32, FALSE, 0, complain_overflow_bitfield,
89 bfd_elf_generic_reloc, "R_386_TLS_GD",
90 TRUE, 0xffffffff, 0xffffffff, FALSE),
91 HOWTO(R_386_TLS_LDM, 0, 2, 32, FALSE, 0, complain_overflow_bitfield,
92 bfd_elf_generic_reloc, "R_386_TLS_LDM",
93 TRUE, 0xffffffff, 0xffffffff, FALSE),
94 HOWTO(R_386_16, 0, 1, 16, FALSE, 0, complain_overflow_bitfield,
95 bfd_elf_generic_reloc, "R_386_16",
96 TRUE, 0xffff, 0xffff, FALSE),
97 HOWTO(R_386_PC16, 0, 1, 16, TRUE, 0, complain_overflow_bitfield,
98 bfd_elf_generic_reloc, "R_386_PC16",
99 TRUE, 0xffff, 0xffff, TRUE),
100 HOWTO(R_386_8, 0, 0, 8, FALSE, 0, complain_overflow_bitfield,
101 bfd_elf_generic_reloc, "R_386_8",
102 TRUE, 0xff, 0xff, FALSE),
103 HOWTO(R_386_PC8, 0, 0, 8, TRUE, 0, complain_overflow_signed,
104 bfd_elf_generic_reloc, "R_386_PC8",
105 TRUE, 0xff, 0xff, TRUE),
106
107 #define R_386_ext (R_386_PC8 + 1 - R_386_ext_offset)
108 #define R_386_tls_offset (R_386_TLS_LDO_32 - R_386_ext)
109 /* These are common with Solaris TLS implementation. */
110 HOWTO(R_386_TLS_LDO_32, 0, 2, 32, FALSE, 0, complain_overflow_bitfield,
111 bfd_elf_generic_reloc, "R_386_TLS_LDO_32",
112 TRUE, 0xffffffff, 0xffffffff, FALSE),
113 HOWTO(R_386_TLS_IE_32, 0, 2, 32, FALSE, 0, complain_overflow_bitfield,
114 bfd_elf_generic_reloc, "R_386_TLS_IE_32",
115 TRUE, 0xffffffff, 0xffffffff, FALSE),
116 HOWTO(R_386_TLS_LE_32, 0, 2, 32, FALSE, 0, complain_overflow_bitfield,
117 bfd_elf_generic_reloc, "R_386_TLS_LE_32",
118 TRUE, 0xffffffff, 0xffffffff, FALSE),
119 HOWTO(R_386_TLS_DTPMOD32, 0, 2, 32, FALSE, 0, complain_overflow_bitfield,
120 bfd_elf_generic_reloc, "R_386_TLS_DTPMOD32",
121 TRUE, 0xffffffff, 0xffffffff, FALSE),
122 HOWTO(R_386_TLS_DTPOFF32, 0, 2, 32, FALSE, 0, complain_overflow_bitfield,
123 bfd_elf_generic_reloc, "R_386_TLS_DTPOFF32",
124 TRUE, 0xffffffff, 0xffffffff, FALSE),
125 HOWTO(R_386_TLS_TPOFF32, 0, 2, 32, FALSE, 0, complain_overflow_bitfield,
126 bfd_elf_generic_reloc, "R_386_TLS_TPOFF32",
127 TRUE, 0xffffffff, 0xffffffff, FALSE),
128
129 /* Another gap. */
130 #define R_386_tls (R_386_TLS_TPOFF32 + 1 - R_386_tls_offset)
131 #define R_386_vt_offset (R_386_GNU_VTINHERIT - R_386_tls)
132
133 /* GNU extension to record C++ vtable hierarchy. */
134 HOWTO (R_386_GNU_VTINHERIT, /* type */
135 0, /* rightshift */
136 2, /* size (0 = byte, 1 = short, 2 = long) */
137 0, /* bitsize */
138 FALSE, /* pc_relative */
139 0, /* bitpos */
140 complain_overflow_dont, /* complain_on_overflow */
141 NULL, /* special_function */
142 "R_386_GNU_VTINHERIT", /* name */
143 FALSE, /* partial_inplace */
144 0, /* src_mask */
145 0, /* dst_mask */
146 FALSE), /* pcrel_offset */
147
148 /* GNU extension to record C++ vtable member usage. */
149 HOWTO (R_386_GNU_VTENTRY, /* type */
150 0, /* rightshift */
151 2, /* size (0 = byte, 1 = short, 2 = long) */
152 0, /* bitsize */
153 FALSE, /* pc_relative */
154 0, /* bitpos */
155 complain_overflow_dont, /* complain_on_overflow */
156 _bfd_elf_rel_vtable_reloc_fn, /* special_function */
157 "R_386_GNU_VTENTRY", /* name */
158 FALSE, /* partial_inplace */
159 0, /* src_mask */
160 0, /* dst_mask */
161 FALSE) /* pcrel_offset */
162
163 #define R_386_vt (R_386_GNU_VTENTRY + 1 - R_386_vt_offset)
164
165 };
166
167 #ifdef DEBUG_GEN_RELOC
168 #define TRACE(str) \
169 fprintf (stderr, "i386 bfd reloc lookup %d (%s)\n", code, str)
170 #else
171 #define TRACE(str)
172 #endif
173
174 static reloc_howto_type *
elf_i386_reloc_type_lookup(bfd * abfd ATTRIBUTE_UNUSED,bfd_reloc_code_real_type code)175 elf_i386_reloc_type_lookup (bfd *abfd ATTRIBUTE_UNUSED,
176 bfd_reloc_code_real_type code)
177 {
178 switch (code)
179 {
180 case BFD_RELOC_NONE:
181 TRACE ("BFD_RELOC_NONE");
182 return &elf_howto_table[R_386_NONE];
183
184 case BFD_RELOC_32:
185 TRACE ("BFD_RELOC_32");
186 return &elf_howto_table[R_386_32];
187
188 case BFD_RELOC_CTOR:
189 TRACE ("BFD_RELOC_CTOR");
190 return &elf_howto_table[R_386_32];
191
192 case BFD_RELOC_32_PCREL:
193 TRACE ("BFD_RELOC_PC32");
194 return &elf_howto_table[R_386_PC32];
195
196 case BFD_RELOC_386_GOT32:
197 TRACE ("BFD_RELOC_386_GOT32");
198 return &elf_howto_table[R_386_GOT32];
199
200 case BFD_RELOC_386_PLT32:
201 TRACE ("BFD_RELOC_386_PLT32");
202 return &elf_howto_table[R_386_PLT32];
203
204 case BFD_RELOC_386_COPY:
205 TRACE ("BFD_RELOC_386_COPY");
206 return &elf_howto_table[R_386_COPY];
207
208 case BFD_RELOC_386_GLOB_DAT:
209 TRACE ("BFD_RELOC_386_GLOB_DAT");
210 return &elf_howto_table[R_386_GLOB_DAT];
211
212 case BFD_RELOC_386_JUMP_SLOT:
213 TRACE ("BFD_RELOC_386_JUMP_SLOT");
214 return &elf_howto_table[R_386_JUMP_SLOT];
215
216 case BFD_RELOC_386_RELATIVE:
217 TRACE ("BFD_RELOC_386_RELATIVE");
218 return &elf_howto_table[R_386_RELATIVE];
219
220 case BFD_RELOC_386_GOTOFF:
221 TRACE ("BFD_RELOC_386_GOTOFF");
222 return &elf_howto_table[R_386_GOTOFF];
223
224 case BFD_RELOC_386_GOTPC:
225 TRACE ("BFD_RELOC_386_GOTPC");
226 return &elf_howto_table[R_386_GOTPC];
227
228 /* These relocs are a GNU extension. */
229 case BFD_RELOC_386_TLS_TPOFF:
230 TRACE ("BFD_RELOC_386_TLS_TPOFF");
231 return &elf_howto_table[R_386_TLS_TPOFF - R_386_ext_offset];
232
233 case BFD_RELOC_386_TLS_IE:
234 TRACE ("BFD_RELOC_386_TLS_IE");
235 return &elf_howto_table[R_386_TLS_IE - R_386_ext_offset];
236
237 case BFD_RELOC_386_TLS_GOTIE:
238 TRACE ("BFD_RELOC_386_TLS_GOTIE");
239 return &elf_howto_table[R_386_TLS_GOTIE - R_386_ext_offset];
240
241 case BFD_RELOC_386_TLS_LE:
242 TRACE ("BFD_RELOC_386_TLS_LE");
243 return &elf_howto_table[R_386_TLS_LE - R_386_ext_offset];
244
245 case BFD_RELOC_386_TLS_GD:
246 TRACE ("BFD_RELOC_386_TLS_GD");
247 return &elf_howto_table[R_386_TLS_GD - R_386_ext_offset];
248
249 case BFD_RELOC_386_TLS_LDM:
250 TRACE ("BFD_RELOC_386_TLS_LDM");
251 return &elf_howto_table[R_386_TLS_LDM - R_386_ext_offset];
252
253 case BFD_RELOC_16:
254 TRACE ("BFD_RELOC_16");
255 return &elf_howto_table[R_386_16 - R_386_ext_offset];
256
257 case BFD_RELOC_16_PCREL:
258 TRACE ("BFD_RELOC_16_PCREL");
259 return &elf_howto_table[R_386_PC16 - R_386_ext_offset];
260
261 case BFD_RELOC_8:
262 TRACE ("BFD_RELOC_8");
263 return &elf_howto_table[R_386_8 - R_386_ext_offset];
264
265 case BFD_RELOC_8_PCREL:
266 TRACE ("BFD_RELOC_8_PCREL");
267 return &elf_howto_table[R_386_PC8 - R_386_ext_offset];
268
269 /* Common with Sun TLS implementation. */
270 case BFD_RELOC_386_TLS_LDO_32:
271 TRACE ("BFD_RELOC_386_TLS_LDO_32");
272 return &elf_howto_table[R_386_TLS_LDO_32 - R_386_tls_offset];
273
274 case BFD_RELOC_386_TLS_IE_32:
275 TRACE ("BFD_RELOC_386_TLS_IE_32");
276 return &elf_howto_table[R_386_TLS_IE_32 - R_386_tls_offset];
277
278 case BFD_RELOC_386_TLS_LE_32:
279 TRACE ("BFD_RELOC_386_TLS_LE_32");
280 return &elf_howto_table[R_386_TLS_LE_32 - R_386_tls_offset];
281
282 case BFD_RELOC_386_TLS_DTPMOD32:
283 TRACE ("BFD_RELOC_386_TLS_DTPMOD32");
284 return &elf_howto_table[R_386_TLS_DTPMOD32 - R_386_tls_offset];
285
286 case BFD_RELOC_386_TLS_DTPOFF32:
287 TRACE ("BFD_RELOC_386_TLS_DTPOFF32");
288 return &elf_howto_table[R_386_TLS_DTPOFF32 - R_386_tls_offset];
289
290 case BFD_RELOC_386_TLS_TPOFF32:
291 TRACE ("BFD_RELOC_386_TLS_TPOFF32");
292 return &elf_howto_table[R_386_TLS_TPOFF32 - R_386_tls_offset];
293
294 case BFD_RELOC_VTABLE_INHERIT:
295 TRACE ("BFD_RELOC_VTABLE_INHERIT");
296 return &elf_howto_table[R_386_GNU_VTINHERIT - R_386_vt_offset];
297
298 case BFD_RELOC_VTABLE_ENTRY:
299 TRACE ("BFD_RELOC_VTABLE_ENTRY");
300 return &elf_howto_table[R_386_GNU_VTENTRY - R_386_vt_offset];
301
302 default:
303 break;
304 }
305
306 TRACE ("Unknown");
307 return 0;
308 }
309
310 static void
elf_i386_info_to_howto_rel(bfd * abfd ATTRIBUTE_UNUSED,arelent * cache_ptr,Elf_Internal_Rela * dst)311 elf_i386_info_to_howto_rel (bfd *abfd ATTRIBUTE_UNUSED,
312 arelent *cache_ptr,
313 Elf_Internal_Rela *dst)
314 {
315 unsigned int r_type = ELF32_R_TYPE (dst->r_info);
316 unsigned int indx;
317
318 if ((indx = r_type) >= R_386_standard
319 && ((indx = r_type - R_386_ext_offset) - R_386_standard
320 >= R_386_ext - R_386_standard)
321 && ((indx = r_type - R_386_tls_offset) - R_386_ext
322 >= R_386_tls - R_386_ext)
323 && ((indx = r_type - R_386_vt_offset) - R_386_tls
324 >= R_386_vt - R_386_tls))
325 {
326 (*_bfd_error_handler) (_("%s: invalid relocation type %d"),
327 bfd_archive_filename (abfd), (int) r_type);
328 indx = R_386_NONE;
329 }
330 cache_ptr->howto = &elf_howto_table[indx];
331 }
332
333 /* Return whether a symbol name implies a local label. The UnixWare
334 2.1 cc generates temporary symbols that start with .X, so we
335 recognize them here. FIXME: do other SVR4 compilers also use .X?.
336 If so, we should move the .X recognition into
337 _bfd_elf_is_local_label_name. */
338
339 static bfd_boolean
elf_i386_is_local_label_name(bfd * abfd,const char * name)340 elf_i386_is_local_label_name (bfd *abfd, const char *name)
341 {
342 if (name[0] == '.' && name[1] == 'X')
343 return TRUE;
344
345 return _bfd_elf_is_local_label_name (abfd, name);
346 }
347
348 /* Support for core dump NOTE sections. */
349
350 static bfd_boolean
elf_i386_grok_prstatus(bfd * abfd,Elf_Internal_Note * note)351 elf_i386_grok_prstatus (bfd *abfd, Elf_Internal_Note *note)
352 {
353 int offset;
354 size_t raw_size;
355
356 if (note->namesz == 8 && strcmp (note->namedata, "FreeBSD") == 0)
357 {
358 int pr_version = bfd_get_32 (abfd, note->descdata);
359
360 if (pr_version != 1)
361 return FALSE;
362
363 /* pr_cursig */
364 elf_tdata (abfd)->core_signal = bfd_get_32 (abfd, note->descdata + 20);
365
366 /* pr_pid */
367 elf_tdata (abfd)->core_pid = bfd_get_32 (abfd, note->descdata + 24);
368
369 /* pr_reg */
370 offset = 28;
371 raw_size = bfd_get_32 (abfd, note->descdata + 8);
372 }
373 else
374 {
375 switch (note->descsz)
376 {
377 default:
378 return FALSE;
379
380 case 144: /* Linux/i386 */
381 /* pr_cursig */
382 elf_tdata (abfd)->core_signal = bfd_get_16 (abfd, note->descdata + 12);
383
384 /* pr_pid */
385 elf_tdata (abfd)->core_pid = bfd_get_32 (abfd, note->descdata + 24);
386
387 /* pr_reg */
388 offset = 72;
389 raw_size = 68;
390
391 break;
392 }
393 }
394
395 /* Make a ".reg/999" section. */
396 return _bfd_elfcore_make_pseudosection (abfd, ".reg",
397 raw_size, note->descpos + offset);
398 }
399
400 static bfd_boolean
elf_i386_grok_psinfo(bfd * abfd,Elf_Internal_Note * note)401 elf_i386_grok_psinfo (bfd *abfd, Elf_Internal_Note *note)
402 {
403 if (note->namesz == 8 && strcmp (note->namedata, "FreeBSD") == 0)
404 {
405 int pr_version = bfd_get_32 (abfd, note->descdata);
406
407 if (pr_version != 1)
408 return FALSE;
409
410 elf_tdata (abfd)->core_program
411 = _bfd_elfcore_strndup (abfd, note->descdata + 8, 17);
412 elf_tdata (abfd)->core_command
413 = _bfd_elfcore_strndup (abfd, note->descdata + 25, 81);
414 }
415 else
416 {
417 switch (note->descsz)
418 {
419 default:
420 return FALSE;
421
422 case 124: /* Linux/i386 elf_prpsinfo. */
423 elf_tdata (abfd)->core_program
424 = _bfd_elfcore_strndup (abfd, note->descdata + 28, 16);
425 elf_tdata (abfd)->core_command
426 = _bfd_elfcore_strndup (abfd, note->descdata + 44, 80);
427 }
428 }
429
430 /* Note that for some reason, a spurious space is tacked
431 onto the end of the args in some (at least one anyway)
432 implementations, so strip it off if it exists. */
433 {
434 char *command = elf_tdata (abfd)->core_command;
435 int n = strlen (command);
436
437 if (0 < n && command[n - 1] == ' ')
438 command[n - 1] = '\0';
439 }
440
441 return TRUE;
442 }
443
444 /* Functions for the i386 ELF linker.
445
446 In order to gain some understanding of code in this file without
447 knowing all the intricate details of the linker, note the
448 following:
449
450 Functions named elf_i386_* are called by external routines, other
451 functions are only called locally. elf_i386_* functions appear
452 in this file more or less in the order in which they are called
453 from external routines. eg. elf_i386_check_relocs is called
454 early in the link process, elf_i386_finish_dynamic_sections is
455 one of the last functions. */
456
457
458 /* The name of the dynamic interpreter. This is put in the .interp
459 section. */
460
461 #define ELF_DYNAMIC_INTERPRETER "/usr/lib/libc.so.1"
462
463 /* If ELIMINATE_COPY_RELOCS is non-zero, the linker will try to avoid
464 copying dynamic variables from a shared lib into an app's dynbss
465 section, and instead use a dynamic relocation to point into the
466 shared lib. */
467 #define ELIMINATE_COPY_RELOCS 1
468
469 /* The size in bytes of an entry in the procedure linkage table. */
470
471 #define PLT_ENTRY_SIZE 16
472
473 /* The first entry in an absolute procedure linkage table looks like
474 this. See the SVR4 ABI i386 supplement to see how this works. */
475
476 static const bfd_byte elf_i386_plt0_entry[PLT_ENTRY_SIZE] =
477 {
478 0xff, 0x35, /* pushl contents of address */
479 0, 0, 0, 0, /* replaced with address of .got + 4. */
480 0xff, 0x25, /* jmp indirect */
481 0, 0, 0, 0, /* replaced with address of .got + 8. */
482 0, 0, 0, 0 /* pad out to 16 bytes. */
483 };
484
485 /* Subsequent entries in an absolute procedure linkage table look like
486 this. */
487
488 static const bfd_byte elf_i386_plt_entry[PLT_ENTRY_SIZE] =
489 {
490 0xff, 0x25, /* jmp indirect */
491 0, 0, 0, 0, /* replaced with address of this symbol in .got. */
492 0x68, /* pushl immediate */
493 0, 0, 0, 0, /* replaced with offset into relocation table. */
494 0xe9, /* jmp relative */
495 0, 0, 0, 0 /* replaced with offset to start of .plt. */
496 };
497
498 /* The first entry in a PIC procedure linkage table look like this. */
499
500 static const bfd_byte elf_i386_pic_plt0_entry[PLT_ENTRY_SIZE] =
501 {
502 0xff, 0xb3, 4, 0, 0, 0, /* pushl 4(%ebx) */
503 0xff, 0xa3, 8, 0, 0, 0, /* jmp *8(%ebx) */
504 0, 0, 0, 0 /* pad out to 16 bytes. */
505 };
506
507 /* Subsequent entries in a PIC procedure linkage table look like this. */
508
509 static const bfd_byte elf_i386_pic_plt_entry[PLT_ENTRY_SIZE] =
510 {
511 0xff, 0xa3, /* jmp *offset(%ebx) */
512 0, 0, 0, 0, /* replaced with offset of this symbol in .got. */
513 0x68, /* pushl immediate */
514 0, 0, 0, 0, /* replaced with offset into relocation table. */
515 0xe9, /* jmp relative */
516 0, 0, 0, 0 /* replaced with offset to start of .plt. */
517 };
518
519 /* The i386 linker needs to keep track of the number of relocs that it
520 decides to copy as dynamic relocs in check_relocs for each symbol.
521 This is so that it can later discard them if they are found to be
522 unnecessary. We store the information in a field extending the
523 regular ELF linker hash table. */
524
525 struct elf_i386_dyn_relocs
526 {
527 struct elf_i386_dyn_relocs *next;
528
529 /* The input section of the reloc. */
530 asection *sec;
531
532 /* Total number of relocs copied for the input section. */
533 bfd_size_type count;
534
535 /* Number of pc-relative relocs copied for the input section. */
536 bfd_size_type pc_count;
537 };
538
539 /* i386 ELF linker hash entry. */
540
541 struct elf_i386_link_hash_entry
542 {
543 struct elf_link_hash_entry elf;
544
545 /* Track dynamic relocs copied for this symbol. */
546 struct elf_i386_dyn_relocs *dyn_relocs;
547
548 #define GOT_UNKNOWN 0
549 #define GOT_NORMAL 1
550 #define GOT_TLS_GD 2
551 #define GOT_TLS_IE 4
552 #define GOT_TLS_IE_POS 5
553 #define GOT_TLS_IE_NEG 6
554 #define GOT_TLS_IE_BOTH 7
555 unsigned char tls_type;
556 };
557
558 #define elf_i386_hash_entry(ent) ((struct elf_i386_link_hash_entry *)(ent))
559
560 struct elf_i386_obj_tdata
561 {
562 struct elf_obj_tdata root;
563
564 /* tls_type for each local got entry. */
565 char *local_got_tls_type;
566 };
567
568 #define elf_i386_tdata(abfd) \
569 ((struct elf_i386_obj_tdata *) (abfd)->tdata.any)
570
571 #define elf_i386_local_got_tls_type(abfd) \
572 (elf_i386_tdata (abfd)->local_got_tls_type)
573
574 static bfd_boolean
elf_i386_mkobject(bfd * abfd)575 elf_i386_mkobject (bfd *abfd)
576 {
577 bfd_size_type amt = sizeof (struct elf_i386_obj_tdata);
578 abfd->tdata.any = bfd_zalloc (abfd, amt);
579 if (abfd->tdata.any == NULL)
580 return FALSE;
581 return TRUE;
582 }
583
584 /* i386 ELF linker hash table. */
585
586 struct elf_i386_link_hash_table
587 {
588 struct elf_link_hash_table elf;
589
590 /* Short-cuts to get to dynamic linker sections. */
591 asection *sgot;
592 asection *sgotplt;
593 asection *srelgot;
594 asection *splt;
595 asection *srelplt;
596 asection *sdynbss;
597 asection *srelbss;
598
599 union {
600 bfd_signed_vma refcount;
601 bfd_vma offset;
602 } tls_ldm_got;
603
604 /* Small local sym to section mapping cache. */
605 struct sym_sec_cache sym_sec;
606 };
607
608 /* Get the i386 ELF linker hash table from a link_info structure. */
609
610 #define elf_i386_hash_table(p) \
611 ((struct elf_i386_link_hash_table *) ((p)->hash))
612
613 /* Create an entry in an i386 ELF linker hash table. */
614
615 static struct bfd_hash_entry *
link_hash_newfunc(struct bfd_hash_entry * entry,struct bfd_hash_table * table,const char * string)616 link_hash_newfunc (struct bfd_hash_entry *entry,
617 struct bfd_hash_table *table,
618 const char *string)
619 {
620 /* Allocate the structure if it has not already been allocated by a
621 subclass. */
622 if (entry == NULL)
623 {
624 entry = bfd_hash_allocate (table,
625 sizeof (struct elf_i386_link_hash_entry));
626 if (entry == NULL)
627 return entry;
628 }
629
630 /* Call the allocation method of the superclass. */
631 entry = _bfd_elf_link_hash_newfunc (entry, table, string);
632 if (entry != NULL)
633 {
634 struct elf_i386_link_hash_entry *eh;
635
636 eh = (struct elf_i386_link_hash_entry *) entry;
637 eh->dyn_relocs = NULL;
638 eh->tls_type = GOT_UNKNOWN;
639 }
640
641 return entry;
642 }
643
644 /* Create an i386 ELF linker hash table. */
645
646 static struct bfd_link_hash_table *
elf_i386_link_hash_table_create(bfd * abfd)647 elf_i386_link_hash_table_create (bfd *abfd)
648 {
649 struct elf_i386_link_hash_table *ret;
650 bfd_size_type amt = sizeof (struct elf_i386_link_hash_table);
651
652 ret = bfd_malloc (amt);
653 if (ret == NULL)
654 return NULL;
655
656 if (! _bfd_elf_link_hash_table_init (&ret->elf, abfd, link_hash_newfunc))
657 {
658 free (ret);
659 return NULL;
660 }
661
662 ret->sgot = NULL;
663 ret->sgotplt = NULL;
664 ret->srelgot = NULL;
665 ret->splt = NULL;
666 ret->srelplt = NULL;
667 ret->sdynbss = NULL;
668 ret->srelbss = NULL;
669 ret->tls_ldm_got.refcount = 0;
670 ret->sym_sec.abfd = NULL;
671
672 return &ret->elf.root;
673 }
674
675 /* Create .got, .gotplt, and .rel.got sections in DYNOBJ, and set up
676 shortcuts to them in our hash table. */
677
678 static bfd_boolean
create_got_section(bfd * dynobj,struct bfd_link_info * info)679 create_got_section (bfd *dynobj, struct bfd_link_info *info)
680 {
681 struct elf_i386_link_hash_table *htab;
682
683 if (! _bfd_elf_create_got_section (dynobj, info))
684 return FALSE;
685
686 htab = elf_i386_hash_table (info);
687 htab->sgot = bfd_get_section_by_name (dynobj, ".got");
688 htab->sgotplt = bfd_get_section_by_name (dynobj, ".got.plt");
689 if (!htab->sgot || !htab->sgotplt)
690 abort ();
691
692 htab->srelgot = bfd_make_section (dynobj, ".rel.got");
693 if (htab->srelgot == NULL
694 || ! bfd_set_section_flags (dynobj, htab->srelgot,
695 (SEC_ALLOC | SEC_LOAD | SEC_HAS_CONTENTS
696 | SEC_IN_MEMORY | SEC_LINKER_CREATED
697 | SEC_READONLY))
698 || ! bfd_set_section_alignment (dynobj, htab->srelgot, 2))
699 return FALSE;
700 return TRUE;
701 }
702
703 /* Create .plt, .rel.plt, .got, .got.plt, .rel.got, .dynbss, and
704 .rel.bss sections in DYNOBJ, and set up shortcuts to them in our
705 hash table. */
706
707 static bfd_boolean
elf_i386_create_dynamic_sections(bfd * dynobj,struct bfd_link_info * info)708 elf_i386_create_dynamic_sections (bfd *dynobj, struct bfd_link_info *info)
709 {
710 struct elf_i386_link_hash_table *htab;
711
712 htab = elf_i386_hash_table (info);
713 if (!htab->sgot && !create_got_section (dynobj, info))
714 return FALSE;
715
716 if (!_bfd_elf_create_dynamic_sections (dynobj, info))
717 return FALSE;
718
719 htab->splt = bfd_get_section_by_name (dynobj, ".plt");
720 htab->srelplt = bfd_get_section_by_name (dynobj, ".rel.plt");
721 htab->sdynbss = bfd_get_section_by_name (dynobj, ".dynbss");
722 if (!info->shared)
723 htab->srelbss = bfd_get_section_by_name (dynobj, ".rel.bss");
724
725 if (!htab->splt || !htab->srelplt || !htab->sdynbss
726 || (!info->shared && !htab->srelbss))
727 abort ();
728
729 return TRUE;
730 }
731
732 /* Copy the extra info we tack onto an elf_link_hash_entry. */
733
734 static void
elf_i386_copy_indirect_symbol(const struct elf_backend_data * bed,struct elf_link_hash_entry * dir,struct elf_link_hash_entry * ind)735 elf_i386_copy_indirect_symbol (const struct elf_backend_data *bed,
736 struct elf_link_hash_entry *dir,
737 struct elf_link_hash_entry *ind)
738 {
739 struct elf_i386_link_hash_entry *edir, *eind;
740
741 edir = (struct elf_i386_link_hash_entry *) dir;
742 eind = (struct elf_i386_link_hash_entry *) ind;
743
744 if (eind->dyn_relocs != NULL)
745 {
746 if (edir->dyn_relocs != NULL)
747 {
748 struct elf_i386_dyn_relocs **pp;
749 struct elf_i386_dyn_relocs *p;
750
751 if (ind->root.type == bfd_link_hash_indirect)
752 abort ();
753
754 /* Add reloc counts against the weak sym to the strong sym
755 list. Merge any entries against the same section. */
756 for (pp = &eind->dyn_relocs; (p = *pp) != NULL; )
757 {
758 struct elf_i386_dyn_relocs *q;
759
760 for (q = edir->dyn_relocs; q != NULL; q = q->next)
761 if (q->sec == p->sec)
762 {
763 q->pc_count += p->pc_count;
764 q->count += p->count;
765 *pp = p->next;
766 break;
767 }
768 if (q == NULL)
769 pp = &p->next;
770 }
771 *pp = edir->dyn_relocs;
772 }
773
774 edir->dyn_relocs = eind->dyn_relocs;
775 eind->dyn_relocs = NULL;
776 }
777
778 if (ind->root.type == bfd_link_hash_indirect
779 && dir->got.refcount <= 0)
780 {
781 edir->tls_type = eind->tls_type;
782 eind->tls_type = GOT_UNKNOWN;
783 }
784
785 if (ELIMINATE_COPY_RELOCS
786 && ind->root.type != bfd_link_hash_indirect
787 && (dir->elf_link_hash_flags & ELF_LINK_HASH_DYNAMIC_ADJUSTED) != 0)
788 /* If called to transfer flags for a weakdef during processing
789 of elf_adjust_dynamic_symbol, don't copy ELF_LINK_NON_GOT_REF.
790 We clear it ourselves for ELIMINATE_COPY_RELOCS. */
791 dir->elf_link_hash_flags |=
792 (ind->elf_link_hash_flags & (ELF_LINK_HASH_REF_DYNAMIC
793 | ELF_LINK_HASH_REF_REGULAR
794 | ELF_LINK_HASH_REF_REGULAR_NONWEAK
795 | ELF_LINK_HASH_NEEDS_PLT
796 | ELF_LINK_POINTER_EQUALITY_NEEDED));
797 else
798 _bfd_elf_link_hash_copy_indirect (bed, dir, ind);
799 }
800
801 static int
elf_i386_tls_transition(struct bfd_link_info * info,int r_type,int is_local)802 elf_i386_tls_transition (struct bfd_link_info *info, int r_type, int is_local)
803 {
804 if (info->shared)
805 return r_type;
806
807 switch (r_type)
808 {
809 case R_386_TLS_GD:
810 case R_386_TLS_IE_32:
811 if (is_local)
812 return R_386_TLS_LE_32;
813 return R_386_TLS_IE_32;
814 case R_386_TLS_IE:
815 case R_386_TLS_GOTIE:
816 if (is_local)
817 return R_386_TLS_LE_32;
818 return r_type;
819 case R_386_TLS_LDM:
820 return R_386_TLS_LE_32;
821 }
822
823 return r_type;
824 }
825
826 /* Look through the relocs for a section during the first phase, and
827 calculate needed space in the global offset table, procedure linkage
828 table, and dynamic reloc sections. */
829
830 static bfd_boolean
elf_i386_check_relocs(bfd * abfd,struct bfd_link_info * info,asection * sec,const Elf_Internal_Rela * relocs)831 elf_i386_check_relocs (bfd *abfd,
832 struct bfd_link_info *info,
833 asection *sec,
834 const Elf_Internal_Rela *relocs)
835 {
836 struct elf_i386_link_hash_table *htab;
837 Elf_Internal_Shdr *symtab_hdr;
838 struct elf_link_hash_entry **sym_hashes;
839 const Elf_Internal_Rela *rel;
840 const Elf_Internal_Rela *rel_end;
841 asection *sreloc;
842
843 if (info->relocatable)
844 return TRUE;
845
846 htab = elf_i386_hash_table (info);
847 symtab_hdr = &elf_tdata (abfd)->symtab_hdr;
848 sym_hashes = elf_sym_hashes (abfd);
849
850 sreloc = NULL;
851
852 rel_end = relocs + sec->reloc_count;
853 for (rel = relocs; rel < rel_end; rel++)
854 {
855 unsigned int r_type;
856 unsigned long r_symndx;
857 struct elf_link_hash_entry *h;
858
859 r_symndx = ELF32_R_SYM (rel->r_info);
860 r_type = ELF32_R_TYPE (rel->r_info);
861
862 if (r_symndx >= NUM_SHDR_ENTRIES (symtab_hdr))
863 {
864 (*_bfd_error_handler) (_("%s: bad symbol index: %d"),
865 bfd_archive_filename (abfd),
866 r_symndx);
867 return FALSE;
868 }
869
870 if (r_symndx < symtab_hdr->sh_info)
871 h = NULL;
872 else
873 h = sym_hashes[r_symndx - symtab_hdr->sh_info];
874
875 r_type = elf_i386_tls_transition (info, r_type, h == NULL);
876
877 switch (r_type)
878 {
879 case R_386_TLS_LDM:
880 htab->tls_ldm_got.refcount += 1;
881 goto create_got;
882
883 case R_386_PLT32:
884 /* This symbol requires a procedure linkage table entry. We
885 actually build the entry in adjust_dynamic_symbol,
886 because this might be a case of linking PIC code which is
887 never referenced by a dynamic object, in which case we
888 don't need to generate a procedure linkage table entry
889 after all. */
890
891 /* If this is a local symbol, we resolve it directly without
892 creating a procedure linkage table entry. */
893 if (h == NULL)
894 continue;
895
896 h->elf_link_hash_flags |= ELF_LINK_HASH_NEEDS_PLT;
897 h->plt.refcount += 1;
898 break;
899
900 case R_386_TLS_IE_32:
901 case R_386_TLS_IE:
902 case R_386_TLS_GOTIE:
903 if (info->shared)
904 info->flags |= DF_STATIC_TLS;
905 /* Fall through */
906
907 case R_386_GOT32:
908 case R_386_TLS_GD:
909 /* This symbol requires a global offset table entry. */
910 {
911 int tls_type, old_tls_type;
912
913 switch (r_type)
914 {
915 default:
916 case R_386_GOT32: tls_type = GOT_NORMAL; break;
917 case R_386_TLS_GD: tls_type = GOT_TLS_GD; break;
918 case R_386_TLS_IE_32:
919 if (ELF32_R_TYPE (rel->r_info) == r_type)
920 tls_type = GOT_TLS_IE_NEG;
921 else
922 /* If this is a GD->IE transition, we may use either of
923 R_386_TLS_TPOFF and R_386_TLS_TPOFF32. */
924 tls_type = GOT_TLS_IE;
925 break;
926 case R_386_TLS_IE:
927 case R_386_TLS_GOTIE:
928 tls_type = GOT_TLS_IE_POS; break;
929 }
930
931 if (h != NULL)
932 {
933 h->got.refcount += 1;
934 old_tls_type = elf_i386_hash_entry(h)->tls_type;
935 }
936 else
937 {
938 bfd_signed_vma *local_got_refcounts;
939
940 /* This is a global offset table entry for a local symbol. */
941 local_got_refcounts = elf_local_got_refcounts (abfd);
942 if (local_got_refcounts == NULL)
943 {
944 bfd_size_type size;
945
946 size = symtab_hdr->sh_info;
947 size *= (sizeof (bfd_signed_vma) + sizeof(char));
948 local_got_refcounts = bfd_zalloc (abfd, size);
949 if (local_got_refcounts == NULL)
950 return FALSE;
951 elf_local_got_refcounts (abfd) = local_got_refcounts;
952 elf_i386_local_got_tls_type (abfd)
953 = (char *) (local_got_refcounts + symtab_hdr->sh_info);
954 }
955 local_got_refcounts[r_symndx] += 1;
956 old_tls_type = elf_i386_local_got_tls_type (abfd) [r_symndx];
957 }
958
959 if ((old_tls_type & GOT_TLS_IE) && (tls_type & GOT_TLS_IE))
960 tls_type |= old_tls_type;
961 /* If a TLS symbol is accessed using IE at least once,
962 there is no point to use dynamic model for it. */
963 else if (old_tls_type != tls_type && old_tls_type != GOT_UNKNOWN
964 && (old_tls_type != GOT_TLS_GD
965 || (tls_type & GOT_TLS_IE) == 0))
966 {
967 if ((old_tls_type & GOT_TLS_IE) && tls_type == GOT_TLS_GD)
968 tls_type = old_tls_type;
969 else
970 {
971 (*_bfd_error_handler)
972 (_("%s: `%s' accessed both as normal and "
973 "thread local symbol"),
974 bfd_archive_filename (abfd),
975 h ? h->root.root.string : "<local>");
976 return FALSE;
977 }
978 }
979
980 if (old_tls_type != tls_type)
981 {
982 if (h != NULL)
983 elf_i386_hash_entry (h)->tls_type = tls_type;
984 else
985 elf_i386_local_got_tls_type (abfd) [r_symndx] = tls_type;
986 }
987 }
988 /* Fall through */
989
990 case R_386_GOTOFF:
991 case R_386_GOTPC:
992 create_got:
993 if (htab->sgot == NULL)
994 {
995 if (htab->elf.dynobj == NULL)
996 htab->elf.dynobj = abfd;
997 if (!create_got_section (htab->elf.dynobj, info))
998 return FALSE;
999 }
1000 if (r_type != R_386_TLS_IE)
1001 break;
1002 /* Fall through */
1003
1004 case R_386_TLS_LE_32:
1005 case R_386_TLS_LE:
1006 if (!info->shared)
1007 break;
1008 info->flags |= DF_STATIC_TLS;
1009 /* Fall through */
1010
1011 case R_386_32:
1012 case R_386_PC32:
1013 if (h != NULL && !info->shared)
1014 {
1015 /* If this reloc is in a read-only section, we might
1016 need a copy reloc. We can't check reliably at this
1017 stage whether the section is read-only, as input
1018 sections have not yet been mapped to output sections.
1019 Tentatively set the flag for now, and correct in
1020 adjust_dynamic_symbol. */
1021 h->elf_link_hash_flags |= ELF_LINK_NON_GOT_REF;
1022
1023 /* We may need a .plt entry if the function this reloc
1024 refers to is in a shared lib. */
1025 h->plt.refcount += 1;
1026 if (r_type != R_386_PC32)
1027 h->elf_link_hash_flags |= ELF_LINK_POINTER_EQUALITY_NEEDED;
1028 }
1029
1030 /* If we are creating a shared library, and this is a reloc
1031 against a global symbol, or a non PC relative reloc
1032 against a local symbol, then we need to copy the reloc
1033 into the shared library. However, if we are linking with
1034 -Bsymbolic, we do not need to copy a reloc against a
1035 global symbol which is defined in an object we are
1036 including in the link (i.e., DEF_REGULAR is set). At
1037 this point we have not seen all the input files, so it is
1038 possible that DEF_REGULAR is not set now but will be set
1039 later (it is never cleared). In case of a weak definition,
1040 DEF_REGULAR may be cleared later by a strong definition in
1041 a shared library. We account for that possibility below by
1042 storing information in the relocs_copied field of the hash
1043 table entry. A similar situation occurs when creating
1044 shared libraries and symbol visibility changes render the
1045 symbol local.
1046
1047 If on the other hand, we are creating an executable, we
1048 may need to keep relocations for symbols satisfied by a
1049 dynamic library if we manage to avoid copy relocs for the
1050 symbol. */
1051 if ((info->shared
1052 && (sec->flags & SEC_ALLOC) != 0
1053 && (r_type != R_386_PC32
1054 || (h != NULL
1055 && (! info->symbolic
1056 || h->root.type == bfd_link_hash_defweak
1057 || (h->elf_link_hash_flags
1058 & ELF_LINK_HASH_DEF_REGULAR) == 0))))
1059 || (ELIMINATE_COPY_RELOCS
1060 && !info->shared
1061 && (sec->flags & SEC_ALLOC) != 0
1062 && h != NULL
1063 && (h->root.type == bfd_link_hash_defweak
1064 || (h->elf_link_hash_flags
1065 & ELF_LINK_HASH_DEF_REGULAR) == 0)))
1066 {
1067 struct elf_i386_dyn_relocs *p;
1068 struct elf_i386_dyn_relocs **head;
1069
1070 /* We must copy these reloc types into the output file.
1071 Create a reloc section in dynobj and make room for
1072 this reloc. */
1073 if (sreloc == NULL)
1074 {
1075 const char *name;
1076 bfd *dynobj;
1077 unsigned int strndx = elf_elfheader (abfd)->e_shstrndx;
1078 unsigned int shnam = elf_section_data (sec)->rel_hdr.sh_name;
1079
1080 name = bfd_elf_string_from_elf_section (abfd, strndx, shnam);
1081 if (name == NULL)
1082 return FALSE;
1083
1084 if (strncmp (name, ".rel", 4) != 0
1085 || strcmp (bfd_get_section_name (abfd, sec),
1086 name + 4) != 0)
1087 {
1088 (*_bfd_error_handler)
1089 (_("%s: bad relocation section name `%s\'"),
1090 bfd_archive_filename (abfd), name);
1091 }
1092
1093 if (htab->elf.dynobj == NULL)
1094 htab->elf.dynobj = abfd;
1095
1096 dynobj = htab->elf.dynobj;
1097 sreloc = bfd_get_section_by_name (dynobj, name);
1098 if (sreloc == NULL)
1099 {
1100 flagword flags;
1101
1102 sreloc = bfd_make_section (dynobj, name);
1103 flags = (SEC_HAS_CONTENTS | SEC_READONLY
1104 | SEC_IN_MEMORY | SEC_LINKER_CREATED);
1105 if ((sec->flags & SEC_ALLOC) != 0)
1106 flags |= SEC_ALLOC | SEC_LOAD;
1107 if (sreloc == NULL
1108 || ! bfd_set_section_flags (dynobj, sreloc, flags)
1109 || ! bfd_set_section_alignment (dynobj, sreloc, 2))
1110 return FALSE;
1111 }
1112 elf_section_data (sec)->sreloc = sreloc;
1113 }
1114
1115 /* If this is a global symbol, we count the number of
1116 relocations we need for this symbol. */
1117 if (h != NULL)
1118 {
1119 head = &((struct elf_i386_link_hash_entry *) h)->dyn_relocs;
1120 }
1121 else
1122 {
1123 /* Track dynamic relocs needed for local syms too.
1124 We really need local syms available to do this
1125 easily. Oh well. */
1126
1127 asection *s;
1128 s = bfd_section_from_r_symndx (abfd, &htab->sym_sec,
1129 sec, r_symndx);
1130 if (s == NULL)
1131 return FALSE;
1132
1133 head = ((struct elf_i386_dyn_relocs **)
1134 &elf_section_data (s)->local_dynrel);
1135 }
1136
1137 p = *head;
1138 if (p == NULL || p->sec != sec)
1139 {
1140 bfd_size_type amt = sizeof *p;
1141 p = bfd_alloc (htab->elf.dynobj, amt);
1142 if (p == NULL)
1143 return FALSE;
1144 p->next = *head;
1145 *head = p;
1146 p->sec = sec;
1147 p->count = 0;
1148 p->pc_count = 0;
1149 }
1150
1151 p->count += 1;
1152 if (r_type == R_386_PC32)
1153 p->pc_count += 1;
1154 }
1155 break;
1156
1157 /* This relocation describes the C++ object vtable hierarchy.
1158 Reconstruct it for later use during GC. */
1159 case R_386_GNU_VTINHERIT:
1160 if (!bfd_elf_gc_record_vtinherit (abfd, sec, h, rel->r_offset))
1161 return FALSE;
1162 break;
1163
1164 /* This relocation describes which C++ vtable entries are actually
1165 used. Record for later use during GC. */
1166 case R_386_GNU_VTENTRY:
1167 if (!bfd_elf_gc_record_vtentry (abfd, sec, h, rel->r_offset))
1168 return FALSE;
1169 break;
1170
1171 default:
1172 break;
1173 }
1174 }
1175
1176 return TRUE;
1177 }
1178
1179 /* Return the section that should be marked against GC for a given
1180 relocation. */
1181
1182 static asection *
elf_i386_gc_mark_hook(asection * sec,struct bfd_link_info * info ATTRIBUTE_UNUSED,Elf_Internal_Rela * rel,struct elf_link_hash_entry * h,Elf_Internal_Sym * sym)1183 elf_i386_gc_mark_hook (asection *sec,
1184 struct bfd_link_info *info ATTRIBUTE_UNUSED,
1185 Elf_Internal_Rela *rel,
1186 struct elf_link_hash_entry *h,
1187 Elf_Internal_Sym *sym)
1188 {
1189 if (h != NULL)
1190 {
1191 switch (ELF32_R_TYPE (rel->r_info))
1192 {
1193 case R_386_GNU_VTINHERIT:
1194 case R_386_GNU_VTENTRY:
1195 break;
1196
1197 default:
1198 switch (h->root.type)
1199 {
1200 case bfd_link_hash_defined:
1201 case bfd_link_hash_defweak:
1202 return h->root.u.def.section;
1203
1204 case bfd_link_hash_common:
1205 return h->root.u.c.p->section;
1206
1207 default:
1208 break;
1209 }
1210 }
1211 }
1212 else
1213 return bfd_section_from_elf_index (sec->owner, sym->st_shndx);
1214
1215 return NULL;
1216 }
1217
1218 /* Update the got entry reference counts for the section being removed. */
1219
1220 static bfd_boolean
elf_i386_gc_sweep_hook(bfd * abfd,struct bfd_link_info * info,asection * sec,const Elf_Internal_Rela * relocs)1221 elf_i386_gc_sweep_hook (bfd *abfd,
1222 struct bfd_link_info *info,
1223 asection *sec,
1224 const Elf_Internal_Rela *relocs)
1225 {
1226 Elf_Internal_Shdr *symtab_hdr;
1227 struct elf_link_hash_entry **sym_hashes;
1228 bfd_signed_vma *local_got_refcounts;
1229 const Elf_Internal_Rela *rel, *relend;
1230
1231 elf_section_data (sec)->local_dynrel = NULL;
1232
1233 symtab_hdr = &elf_tdata (abfd)->symtab_hdr;
1234 sym_hashes = elf_sym_hashes (abfd);
1235 local_got_refcounts = elf_local_got_refcounts (abfd);
1236
1237 relend = relocs + sec->reloc_count;
1238 for (rel = relocs; rel < relend; rel++)
1239 {
1240 unsigned long r_symndx;
1241 unsigned int r_type;
1242 struct elf_link_hash_entry *h = NULL;
1243
1244 r_symndx = ELF32_R_SYM (rel->r_info);
1245 if (r_symndx >= symtab_hdr->sh_info)
1246 {
1247 struct elf_i386_link_hash_entry *eh;
1248 struct elf_i386_dyn_relocs **pp;
1249 struct elf_i386_dyn_relocs *p;
1250
1251 h = sym_hashes[r_symndx - symtab_hdr->sh_info];
1252 eh = (struct elf_i386_link_hash_entry *) h;
1253
1254 for (pp = &eh->dyn_relocs; (p = *pp) != NULL; pp = &p->next)
1255 if (p->sec == sec)
1256 {
1257 /* Everything must go for SEC. */
1258 *pp = p->next;
1259 break;
1260 }
1261 }
1262
1263 r_type = ELF32_R_TYPE (rel->r_info);
1264 r_type = elf_i386_tls_transition (info, r_type, h != NULL);
1265 switch (r_type)
1266 {
1267 case R_386_TLS_LDM:
1268 if (elf_i386_hash_table (info)->tls_ldm_got.refcount > 0)
1269 elf_i386_hash_table (info)->tls_ldm_got.refcount -= 1;
1270 break;
1271
1272 case R_386_TLS_GD:
1273 case R_386_TLS_IE_32:
1274 case R_386_TLS_IE:
1275 case R_386_TLS_GOTIE:
1276 case R_386_GOT32:
1277 if (h != NULL)
1278 {
1279 if (h->got.refcount > 0)
1280 h->got.refcount -= 1;
1281 }
1282 else if (local_got_refcounts != NULL)
1283 {
1284 if (local_got_refcounts[r_symndx] > 0)
1285 local_got_refcounts[r_symndx] -= 1;
1286 }
1287 break;
1288
1289 case R_386_32:
1290 case R_386_PC32:
1291 if (info->shared)
1292 break;
1293 /* Fall through */
1294
1295 case R_386_PLT32:
1296 if (h != NULL)
1297 {
1298 if (h->plt.refcount > 0)
1299 h->plt.refcount -= 1;
1300 }
1301 break;
1302
1303 default:
1304 break;
1305 }
1306 }
1307
1308 return TRUE;
1309 }
1310
1311 /* Adjust a symbol defined by a dynamic object and referenced by a
1312 regular object. The current definition is in some section of the
1313 dynamic object, but we're not including those sections. We have to
1314 change the definition to something the rest of the link can
1315 understand. */
1316
1317 static bfd_boolean
elf_i386_adjust_dynamic_symbol(struct bfd_link_info * info,struct elf_link_hash_entry * h)1318 elf_i386_adjust_dynamic_symbol (struct bfd_link_info *info,
1319 struct elf_link_hash_entry *h)
1320 {
1321 struct elf_i386_link_hash_table *htab;
1322 asection *s;
1323 unsigned int power_of_two;
1324
1325 /* If this is a function, put it in the procedure linkage table. We
1326 will fill in the contents of the procedure linkage table later,
1327 when we know the address of the .got section. */
1328 if (h->type == STT_FUNC
1329 || (h->elf_link_hash_flags & ELF_LINK_HASH_NEEDS_PLT) != 0)
1330 {
1331 if (h->plt.refcount <= 0
1332 || SYMBOL_CALLS_LOCAL (info, h)
1333 || (ELF_ST_VISIBILITY (h->other) != STV_DEFAULT
1334 && h->root.type == bfd_link_hash_undefweak))
1335 {
1336 /* This case can occur if we saw a PLT32 reloc in an input
1337 file, but the symbol was never referred to by a dynamic
1338 object, or if all references were garbage collected. In
1339 such a case, we don't actually need to build a procedure
1340 linkage table, and we can just do a PC32 reloc instead. */
1341 h->plt.offset = (bfd_vma) -1;
1342 h->elf_link_hash_flags &= ~ELF_LINK_HASH_NEEDS_PLT;
1343 }
1344
1345 return TRUE;
1346 }
1347 else
1348 /* It's possible that we incorrectly decided a .plt reloc was
1349 needed for an R_386_PC32 reloc to a non-function sym in
1350 check_relocs. We can't decide accurately between function and
1351 non-function syms in check-relocs; Objects loaded later in
1352 the link may change h->type. So fix it now. */
1353 h->plt.offset = (bfd_vma) -1;
1354
1355 /* If this is a weak symbol, and there is a real definition, the
1356 processor independent code will have arranged for us to see the
1357 real definition first, and we can just use the same value. */
1358 if (h->weakdef != NULL)
1359 {
1360 BFD_ASSERT (h->weakdef->root.type == bfd_link_hash_defined
1361 || h->weakdef->root.type == bfd_link_hash_defweak);
1362 h->root.u.def.section = h->weakdef->root.u.def.section;
1363 h->root.u.def.value = h->weakdef->root.u.def.value;
1364 if (ELIMINATE_COPY_RELOCS || info->nocopyreloc)
1365 h->elf_link_hash_flags
1366 = ((h->elf_link_hash_flags & ~ELF_LINK_NON_GOT_REF)
1367 | (h->weakdef->elf_link_hash_flags & ELF_LINK_NON_GOT_REF));
1368 return TRUE;
1369 }
1370
1371 /* This is a reference to a symbol defined by a dynamic object which
1372 is not a function. */
1373
1374 /* If we are creating a shared library, we must presume that the
1375 only references to the symbol are via the global offset table.
1376 For such cases we need not do anything here; the relocations will
1377 be handled correctly by relocate_section. */
1378 if (info->shared)
1379 return TRUE;
1380
1381 /* If there are no references to this symbol that do not use the
1382 GOT, we don't need to generate a copy reloc. */
1383 if ((h->elf_link_hash_flags & ELF_LINK_NON_GOT_REF) == 0)
1384 return TRUE;
1385
1386 /* If -z nocopyreloc was given, we won't generate them either. */
1387 if (info->nocopyreloc)
1388 {
1389 h->elf_link_hash_flags &= ~ELF_LINK_NON_GOT_REF;
1390 return TRUE;
1391 }
1392
1393 if (ELIMINATE_COPY_RELOCS)
1394 {
1395 struct elf_i386_link_hash_entry * eh;
1396 struct elf_i386_dyn_relocs *p;
1397
1398 eh = (struct elf_i386_link_hash_entry *) h;
1399 for (p = eh->dyn_relocs; p != NULL; p = p->next)
1400 {
1401 s = p->sec->output_section;
1402 if (s != NULL && (s->flags & SEC_READONLY) != 0)
1403 break;
1404 }
1405
1406 /* If we didn't find any dynamic relocs in read-only sections, then
1407 we'll be keeping the dynamic relocs and avoiding the copy reloc. */
1408 if (p == NULL)
1409 {
1410 h->elf_link_hash_flags &= ~ELF_LINK_NON_GOT_REF;
1411 return TRUE;
1412 }
1413 }
1414
1415 /* We must allocate the symbol in our .dynbss section, which will
1416 become part of the .bss section of the executable. There will be
1417 an entry for this symbol in the .dynsym section. The dynamic
1418 object will contain position independent code, so all references
1419 from the dynamic object to this symbol will go through the global
1420 offset table. The dynamic linker will use the .dynsym entry to
1421 determine the address it must put in the global offset table, so
1422 both the dynamic object and the regular object will refer to the
1423 same memory location for the variable. */
1424
1425 htab = elf_i386_hash_table (info);
1426
1427 /* We must generate a R_386_COPY reloc to tell the dynamic linker to
1428 copy the initial value out of the dynamic object and into the
1429 runtime process image. */
1430 if ((h->root.u.def.section->flags & SEC_ALLOC) != 0)
1431 {
1432 htab->srelbss->_raw_size += sizeof (Elf32_External_Rel);
1433 h->elf_link_hash_flags |= ELF_LINK_HASH_NEEDS_COPY;
1434 }
1435
1436 /* We need to figure out the alignment required for this symbol. I
1437 have no idea how ELF linkers handle this. */
1438 power_of_two = bfd_log2 (h->size);
1439 if (power_of_two > 3)
1440 power_of_two = 3;
1441
1442 /* Apply the required alignment. */
1443 s = htab->sdynbss;
1444 s->_raw_size = BFD_ALIGN (s->_raw_size, (bfd_size_type) (1 << power_of_two));
1445 if (power_of_two > bfd_get_section_alignment (htab->elf.dynobj, s))
1446 {
1447 if (! bfd_set_section_alignment (htab->elf.dynobj, s, power_of_two))
1448 return FALSE;
1449 }
1450
1451 /* Define the symbol as being at this point in the section. */
1452 h->root.u.def.section = s;
1453 h->root.u.def.value = s->_raw_size;
1454
1455 /* Increment the section size to make room for the symbol. */
1456 s->_raw_size += h->size;
1457
1458 return TRUE;
1459 }
1460
1461 /* Allocate space in .plt, .got and associated reloc sections for
1462 dynamic relocs. */
1463
1464 static bfd_boolean
allocate_dynrelocs(struct elf_link_hash_entry * h,void * inf)1465 allocate_dynrelocs (struct elf_link_hash_entry *h, void *inf)
1466 {
1467 struct bfd_link_info *info;
1468 struct elf_i386_link_hash_table *htab;
1469 struct elf_i386_link_hash_entry *eh;
1470 struct elf_i386_dyn_relocs *p;
1471
1472 if (h->root.type == bfd_link_hash_indirect)
1473 return TRUE;
1474
1475 if (h->root.type == bfd_link_hash_warning)
1476 /* When warning symbols are created, they **replace** the "real"
1477 entry in the hash table, thus we never get to see the real
1478 symbol in a hash traversal. So look at it now. */
1479 h = (struct elf_link_hash_entry *) h->root.u.i.link;
1480
1481 info = (struct bfd_link_info *) inf;
1482 htab = elf_i386_hash_table (info);
1483
1484 if (htab->elf.dynamic_sections_created
1485 && h->plt.refcount > 0)
1486 {
1487 /* Make sure this symbol is output as a dynamic symbol.
1488 Undefined weak syms won't yet be marked as dynamic. */
1489 if (h->dynindx == -1
1490 && (h->elf_link_hash_flags & ELF_LINK_FORCED_LOCAL) == 0)
1491 {
1492 if (! bfd_elf_link_record_dynamic_symbol (info, h))
1493 return FALSE;
1494 }
1495
1496 if (info->shared
1497 || WILL_CALL_FINISH_DYNAMIC_SYMBOL (1, 0, h))
1498 {
1499 asection *s = htab->splt;
1500
1501 /* If this is the first .plt entry, make room for the special
1502 first entry. */
1503 if (s->_raw_size == 0)
1504 s->_raw_size += PLT_ENTRY_SIZE;
1505
1506 h->plt.offset = s->_raw_size;
1507
1508 /* If this symbol is not defined in a regular file, and we are
1509 not generating a shared library, then set the symbol to this
1510 location in the .plt. This is required to make function
1511 pointers compare as equal between the normal executable and
1512 the shared library. */
1513 if (! info->shared
1514 && (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR) == 0)
1515 {
1516 h->root.u.def.section = s;
1517 h->root.u.def.value = h->plt.offset;
1518 }
1519
1520 /* Make room for this entry. */
1521 s->_raw_size += PLT_ENTRY_SIZE;
1522
1523 /* We also need to make an entry in the .got.plt section, which
1524 will be placed in the .got section by the linker script. */
1525 htab->sgotplt->_raw_size += 4;
1526
1527 /* We also need to make an entry in the .rel.plt section. */
1528 htab->srelplt->_raw_size += sizeof (Elf32_External_Rel);
1529 }
1530 else
1531 {
1532 h->plt.offset = (bfd_vma) -1;
1533 h->elf_link_hash_flags &= ~ELF_LINK_HASH_NEEDS_PLT;
1534 }
1535 }
1536 else
1537 {
1538 h->plt.offset = (bfd_vma) -1;
1539 h->elf_link_hash_flags &= ~ELF_LINK_HASH_NEEDS_PLT;
1540 }
1541
1542 /* If R_386_TLS_{IE_32,IE,GOTIE} symbol is now local to the binary,
1543 make it a R_386_TLS_LE_32 requiring no TLS entry. */
1544 if (h->got.refcount > 0
1545 && !info->shared
1546 && h->dynindx == -1
1547 && (elf_i386_hash_entry(h)->tls_type & GOT_TLS_IE))
1548 h->got.offset = (bfd_vma) -1;
1549 else if (h->got.refcount > 0)
1550 {
1551 asection *s;
1552 bfd_boolean dyn;
1553 int tls_type = elf_i386_hash_entry(h)->tls_type;
1554
1555 /* Make sure this symbol is output as a dynamic symbol.
1556 Undefined weak syms won't yet be marked as dynamic. */
1557 if (h->dynindx == -1
1558 && (h->elf_link_hash_flags & ELF_LINK_FORCED_LOCAL) == 0)
1559 {
1560 if (! bfd_elf_link_record_dynamic_symbol (info, h))
1561 return FALSE;
1562 }
1563
1564 s = htab->sgot;
1565 h->got.offset = s->_raw_size;
1566 s->_raw_size += 4;
1567 /* R_386_TLS_GD needs 2 consecutive GOT slots. */
1568 if (tls_type == GOT_TLS_GD || tls_type == GOT_TLS_IE_BOTH)
1569 s->_raw_size += 4;
1570 dyn = htab->elf.dynamic_sections_created;
1571 /* R_386_TLS_IE_32 needs one dynamic relocation,
1572 R_386_TLS_IE resp. R_386_TLS_GOTIE needs one dynamic relocation,
1573 (but if both R_386_TLS_IE_32 and R_386_TLS_IE is present, we
1574 need two), R_386_TLS_GD needs one if local symbol and two if
1575 global. */
1576 if (tls_type == GOT_TLS_IE_BOTH)
1577 htab->srelgot->_raw_size += 2 * sizeof (Elf32_External_Rel);
1578 else if ((tls_type == GOT_TLS_GD && h->dynindx == -1)
1579 || (tls_type & GOT_TLS_IE))
1580 htab->srelgot->_raw_size += sizeof (Elf32_External_Rel);
1581 else if (tls_type == GOT_TLS_GD)
1582 htab->srelgot->_raw_size += 2 * sizeof (Elf32_External_Rel);
1583 else if ((ELF_ST_VISIBILITY (h->other) == STV_DEFAULT
1584 || h->root.type != bfd_link_hash_undefweak)
1585 && (info->shared
1586 || WILL_CALL_FINISH_DYNAMIC_SYMBOL (dyn, 0, h)))
1587 htab->srelgot->_raw_size += sizeof (Elf32_External_Rel);
1588 }
1589 else
1590 h->got.offset = (bfd_vma) -1;
1591
1592 eh = (struct elf_i386_link_hash_entry *) h;
1593 if (eh->dyn_relocs == NULL)
1594 return TRUE;
1595
1596 /* In the shared -Bsymbolic case, discard space allocated for
1597 dynamic pc-relative relocs against symbols which turn out to be
1598 defined in regular objects. For the normal shared case, discard
1599 space for pc-relative relocs that have become local due to symbol
1600 visibility changes. */
1601
1602 if (info->shared)
1603 {
1604 /* The only reloc that uses pc_count is R_386_PC32, which will
1605 appear on a call or on something like ".long foo - .". We
1606 want calls to protected symbols to resolve directly to the
1607 function rather than going via the plt. If people want
1608 function pointer comparisons to work as expected then they
1609 should avoid writing assembly like ".long foo - .". */
1610 if (SYMBOL_CALLS_LOCAL (info, h))
1611 {
1612 struct elf_i386_dyn_relocs **pp;
1613
1614 for (pp = &eh->dyn_relocs; (p = *pp) != NULL; )
1615 {
1616 p->count -= p->pc_count;
1617 p->pc_count = 0;
1618 if (p->count == 0)
1619 *pp = p->next;
1620 else
1621 pp = &p->next;
1622 }
1623 }
1624
1625 /* Also discard relocs on undefined weak syms with non-default
1626 visibility. */
1627 if (ELF_ST_VISIBILITY (h->other) != STV_DEFAULT
1628 && h->root.type == bfd_link_hash_undefweak)
1629 eh->dyn_relocs = NULL;
1630 }
1631 else if (ELIMINATE_COPY_RELOCS)
1632 {
1633 /* For the non-shared case, discard space for relocs against
1634 symbols which turn out to need copy relocs or are not
1635 dynamic. */
1636
1637 if ((h->elf_link_hash_flags & ELF_LINK_NON_GOT_REF) == 0
1638 && (((h->elf_link_hash_flags & ELF_LINK_HASH_DEF_DYNAMIC) != 0
1639 && (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR) == 0)
1640 || (htab->elf.dynamic_sections_created
1641 && (h->root.type == bfd_link_hash_undefweak
1642 || h->root.type == bfd_link_hash_undefined))))
1643 {
1644 /* Make sure this symbol is output as a dynamic symbol.
1645 Undefined weak syms won't yet be marked as dynamic. */
1646 if (h->dynindx == -1
1647 && (h->elf_link_hash_flags & ELF_LINK_FORCED_LOCAL) == 0)
1648 {
1649 if (! bfd_elf_link_record_dynamic_symbol (info, h))
1650 return FALSE;
1651 }
1652
1653 /* If that succeeded, we know we'll be keeping all the
1654 relocs. */
1655 if (h->dynindx != -1)
1656 goto keep;
1657 }
1658
1659 eh->dyn_relocs = NULL;
1660
1661 keep: ;
1662 }
1663
1664 /* Finally, allocate space. */
1665 for (p = eh->dyn_relocs; p != NULL; p = p->next)
1666 {
1667 asection *sreloc = elf_section_data (p->sec)->sreloc;
1668 sreloc->_raw_size += p->count * sizeof (Elf32_External_Rel);
1669 }
1670
1671 return TRUE;
1672 }
1673
1674 /* Find any dynamic relocs that apply to read-only sections. */
1675
1676 static bfd_boolean
readonly_dynrelocs(struct elf_link_hash_entry * h,void * inf)1677 readonly_dynrelocs (struct elf_link_hash_entry *h, void *inf)
1678 {
1679 struct elf_i386_link_hash_entry *eh;
1680 struct elf_i386_dyn_relocs *p;
1681
1682 if (h->root.type == bfd_link_hash_warning)
1683 h = (struct elf_link_hash_entry *) h->root.u.i.link;
1684
1685 eh = (struct elf_i386_link_hash_entry *) h;
1686 for (p = eh->dyn_relocs; p != NULL; p = p->next)
1687 {
1688 asection *s = p->sec->output_section;
1689
1690 if (s != NULL && (s->flags & SEC_READONLY) != 0)
1691 {
1692 struct bfd_link_info *info = (struct bfd_link_info *) inf;
1693
1694 info->flags |= DF_TEXTREL;
1695
1696 /* Not an error, just cut short the traversal. */
1697 return FALSE;
1698 }
1699 }
1700 return TRUE;
1701 }
1702
1703 /* Set the sizes of the dynamic sections. */
1704
1705 static bfd_boolean
elf_i386_size_dynamic_sections(bfd * output_bfd ATTRIBUTE_UNUSED,struct bfd_link_info * info)1706 elf_i386_size_dynamic_sections (bfd *output_bfd ATTRIBUTE_UNUSED,
1707 struct bfd_link_info *info)
1708 {
1709 struct elf_i386_link_hash_table *htab;
1710 bfd *dynobj;
1711 asection *s;
1712 bfd_boolean relocs;
1713 bfd *ibfd;
1714
1715 htab = elf_i386_hash_table (info);
1716 dynobj = htab->elf.dynobj;
1717 if (dynobj == NULL)
1718 abort ();
1719
1720 if (htab->elf.dynamic_sections_created)
1721 {
1722 /* Set the contents of the .interp section to the interpreter. */
1723 if (info->executable)
1724 {
1725 s = bfd_get_section_by_name (dynobj, ".interp");
1726 if (s == NULL)
1727 abort ();
1728 s->_raw_size = sizeof ELF_DYNAMIC_INTERPRETER;
1729 s->contents = (unsigned char *) ELF_DYNAMIC_INTERPRETER;
1730 }
1731 }
1732
1733 /* Set up .got offsets for local syms, and space for local dynamic
1734 relocs. */
1735 for (ibfd = info->input_bfds; ibfd != NULL; ibfd = ibfd->link_next)
1736 {
1737 bfd_signed_vma *local_got;
1738 bfd_signed_vma *end_local_got;
1739 char *local_tls_type;
1740 bfd_size_type locsymcount;
1741 Elf_Internal_Shdr *symtab_hdr;
1742 asection *srel;
1743
1744 if (bfd_get_flavour (ibfd) != bfd_target_elf_flavour)
1745 continue;
1746
1747 for (s = ibfd->sections; s != NULL; s = s->next)
1748 {
1749 struct elf_i386_dyn_relocs *p;
1750
1751 for (p = *((struct elf_i386_dyn_relocs **)
1752 &elf_section_data (s)->local_dynrel);
1753 p != NULL;
1754 p = p->next)
1755 {
1756 if (!bfd_is_abs_section (p->sec)
1757 && bfd_is_abs_section (p->sec->output_section))
1758 {
1759 /* Input section has been discarded, either because
1760 it is a copy of a linkonce section or due to
1761 linker script /DISCARD/, so we'll be discarding
1762 the relocs too. */
1763 }
1764 else if (p->count != 0)
1765 {
1766 srel = elf_section_data (p->sec)->sreloc;
1767 srel->_raw_size += p->count * sizeof (Elf32_External_Rel);
1768 if ((p->sec->output_section->flags & SEC_READONLY) != 0)
1769 info->flags |= DF_TEXTREL;
1770 }
1771 }
1772 }
1773
1774 local_got = elf_local_got_refcounts (ibfd);
1775 if (!local_got)
1776 continue;
1777
1778 symtab_hdr = &elf_tdata (ibfd)->symtab_hdr;
1779 locsymcount = symtab_hdr->sh_info;
1780 end_local_got = local_got + locsymcount;
1781 local_tls_type = elf_i386_local_got_tls_type (ibfd);
1782 s = htab->sgot;
1783 srel = htab->srelgot;
1784 for (; local_got < end_local_got; ++local_got, ++local_tls_type)
1785 {
1786 if (*local_got > 0)
1787 {
1788 *local_got = s->_raw_size;
1789 s->_raw_size += 4;
1790 if (*local_tls_type == GOT_TLS_GD
1791 || *local_tls_type == GOT_TLS_IE_BOTH)
1792 s->_raw_size += 4;
1793 if (info->shared
1794 || *local_tls_type == GOT_TLS_GD
1795 || (*local_tls_type & GOT_TLS_IE))
1796 {
1797 if (*local_tls_type == GOT_TLS_IE_BOTH)
1798 srel->_raw_size += 2 * sizeof (Elf32_External_Rel);
1799 else
1800 srel->_raw_size += sizeof (Elf32_External_Rel);
1801 }
1802 }
1803 else
1804 *local_got = (bfd_vma) -1;
1805 }
1806 }
1807
1808 if (htab->tls_ldm_got.refcount > 0)
1809 {
1810 /* Allocate 2 got entries and 1 dynamic reloc for R_386_TLS_LDM
1811 relocs. */
1812 htab->tls_ldm_got.offset = htab->sgot->_raw_size;
1813 htab->sgot->_raw_size += 8;
1814 htab->srelgot->_raw_size += sizeof (Elf32_External_Rel);
1815 }
1816 else
1817 htab->tls_ldm_got.offset = -1;
1818
1819 /* Allocate global sym .plt and .got entries, and space for global
1820 sym dynamic relocs. */
1821 elf_link_hash_traverse (&htab->elf, allocate_dynrelocs, (PTR) info);
1822
1823 /* We now have determined the sizes of the various dynamic sections.
1824 Allocate memory for them. */
1825 relocs = FALSE;
1826 for (s = dynobj->sections; s != NULL; s = s->next)
1827 {
1828 if ((s->flags & SEC_LINKER_CREATED) == 0)
1829 continue;
1830
1831 if (s == htab->splt
1832 || s == htab->sgot
1833 || s == htab->sgotplt)
1834 {
1835 /* Strip this section if we don't need it; see the
1836 comment below. */
1837 }
1838 else if (strncmp (bfd_get_section_name (dynobj, s), ".rel", 4) == 0)
1839 {
1840 if (s->_raw_size != 0 && s != htab->srelplt)
1841 relocs = TRUE;
1842
1843 /* We use the reloc_count field as a counter if we need
1844 to copy relocs into the output file. */
1845 s->reloc_count = 0;
1846 }
1847 else
1848 {
1849 /* It's not one of our sections, so don't allocate space. */
1850 continue;
1851 }
1852
1853 if (s->_raw_size == 0)
1854 {
1855 /* If we don't need this section, strip it from the
1856 output file. This is mostly to handle .rel.bss and
1857 .rel.plt. We must create both sections in
1858 create_dynamic_sections, because they must be created
1859 before the linker maps input sections to output
1860 sections. The linker does that before
1861 adjust_dynamic_symbol is called, and it is that
1862 function which decides whether anything needs to go
1863 into these sections. */
1864
1865 _bfd_strip_section_from_output (info, s);
1866 continue;
1867 }
1868
1869 /* Allocate memory for the section contents. We use bfd_zalloc
1870 here in case unused entries are not reclaimed before the
1871 section's contents are written out. This should not happen,
1872 but this way if it does, we get a R_386_NONE reloc instead
1873 of garbage. */
1874 s->contents = bfd_zalloc (dynobj, s->_raw_size);
1875 if (s->contents == NULL)
1876 return FALSE;
1877 }
1878
1879 if (htab->elf.dynamic_sections_created)
1880 {
1881 /* Add some entries to the .dynamic section. We fill in the
1882 values later, in elf_i386_finish_dynamic_sections, but we
1883 must add the entries now so that we get the correct size for
1884 the .dynamic section. The DT_DEBUG entry is filled in by the
1885 dynamic linker and used by the debugger. */
1886 #define add_dynamic_entry(TAG, VAL) \
1887 _bfd_elf_add_dynamic_entry (info, TAG, VAL)
1888
1889 if (info->executable)
1890 {
1891 if (!add_dynamic_entry (DT_DEBUG, 0))
1892 return FALSE;
1893 }
1894
1895 if (htab->splt->_raw_size != 0)
1896 {
1897 if (!add_dynamic_entry (DT_PLTGOT, 0)
1898 || !add_dynamic_entry (DT_PLTRELSZ, 0)
1899 || !add_dynamic_entry (DT_PLTREL, DT_REL)
1900 || !add_dynamic_entry (DT_JMPREL, 0))
1901 return FALSE;
1902 }
1903
1904 if (relocs)
1905 {
1906 if (!add_dynamic_entry (DT_REL, 0)
1907 || !add_dynamic_entry (DT_RELSZ, 0)
1908 || !add_dynamic_entry (DT_RELENT, sizeof (Elf32_External_Rel)))
1909 return FALSE;
1910
1911 /* If any dynamic relocs apply to a read-only section,
1912 then we need a DT_TEXTREL entry. */
1913 if ((info->flags & DF_TEXTREL) == 0)
1914 elf_link_hash_traverse (&htab->elf, readonly_dynrelocs,
1915 (PTR) info);
1916
1917 if ((info->flags & DF_TEXTREL) != 0)
1918 {
1919 if (!add_dynamic_entry (DT_TEXTREL, 0))
1920 return FALSE;
1921 }
1922 }
1923 }
1924 #undef add_dynamic_entry
1925
1926 return TRUE;
1927 }
1928
1929 /* Set the correct type for an x86 ELF section. We do this by the
1930 section name, which is a hack, but ought to work. */
1931
1932 static bfd_boolean
elf_i386_fake_sections(bfd * abfd ATTRIBUTE_UNUSED,Elf_Internal_Shdr * hdr,asection * sec)1933 elf_i386_fake_sections (bfd *abfd ATTRIBUTE_UNUSED,
1934 Elf_Internal_Shdr *hdr,
1935 asection *sec)
1936 {
1937 register const char *name;
1938
1939 name = bfd_get_section_name (abfd, sec);
1940
1941 /* This is an ugly, but unfortunately necessary hack that is
1942 needed when producing EFI binaries on x86. It tells
1943 elf.c:elf_fake_sections() not to consider ".reloc" as a section
1944 containing ELF relocation info. We need this hack in order to
1945 be able to generate ELF binaries that can be translated into
1946 EFI applications (which are essentially COFF objects). Those
1947 files contain a COFF ".reloc" section inside an ELFNN object,
1948 which would normally cause BFD to segfault because it would
1949 attempt to interpret this section as containing relocation
1950 entries for section "oc". With this hack enabled, ".reloc"
1951 will be treated as a normal data section, which will avoid the
1952 segfault. However, you won't be able to create an ELFNN binary
1953 with a section named "oc" that needs relocations, but that's
1954 the kind of ugly side-effects you get when detecting section
1955 types based on their names... In practice, this limitation is
1956 unlikely to bite. */
1957 if (strcmp (name, ".reloc") == 0)
1958 hdr->sh_type = SHT_PROGBITS;
1959
1960 return TRUE;
1961 }
1962
1963 /* Return the base VMA address which should be subtracted from real addresses
1964 when resolving @dtpoff relocation.
1965 This is PT_TLS segment p_vaddr. */
1966
1967 static bfd_vma
dtpoff_base(struct bfd_link_info * info)1968 dtpoff_base (struct bfd_link_info *info)
1969 {
1970 /* If tls_sec is NULL, we should have signalled an error already. */
1971 if (elf_hash_table (info)->tls_sec == NULL)
1972 return 0;
1973 return elf_hash_table (info)->tls_sec->vma;
1974 }
1975
1976 /* Return the relocation value for @tpoff relocation
1977 if STT_TLS virtual address is ADDRESS. */
1978
1979 static bfd_vma
tpoff(struct bfd_link_info * info,bfd_vma address)1980 tpoff (struct bfd_link_info *info, bfd_vma address)
1981 {
1982 struct elf_link_hash_table *htab = elf_hash_table (info);
1983
1984 /* If tls_sec is NULL, we should have signalled an error already. */
1985 if (htab->tls_sec == NULL)
1986 return 0;
1987 return htab->tls_size + htab->tls_sec->vma - address;
1988 }
1989
1990 /* Relocate an i386 ELF section. */
1991
1992 static bfd_boolean
elf_i386_relocate_section(bfd * output_bfd,struct bfd_link_info * info,bfd * input_bfd,asection * input_section,bfd_byte * contents,Elf_Internal_Rela * relocs,Elf_Internal_Sym * local_syms,asection ** local_sections)1993 elf_i386_relocate_section (bfd *output_bfd,
1994 struct bfd_link_info *info,
1995 bfd *input_bfd,
1996 asection *input_section,
1997 bfd_byte *contents,
1998 Elf_Internal_Rela *relocs,
1999 Elf_Internal_Sym *local_syms,
2000 asection **local_sections)
2001 {
2002 struct elf_i386_link_hash_table *htab;
2003 Elf_Internal_Shdr *symtab_hdr;
2004 struct elf_link_hash_entry **sym_hashes;
2005 bfd_vma *local_got_offsets;
2006 Elf_Internal_Rela *rel;
2007 Elf_Internal_Rela *relend;
2008
2009 htab = elf_i386_hash_table (info);
2010 symtab_hdr = &elf_tdata (input_bfd)->symtab_hdr;
2011 sym_hashes = elf_sym_hashes (input_bfd);
2012 local_got_offsets = elf_local_got_offsets (input_bfd);
2013
2014 rel = relocs;
2015 relend = relocs + input_section->reloc_count;
2016 for (; rel < relend; rel++)
2017 {
2018 unsigned int r_type;
2019 reloc_howto_type *howto;
2020 unsigned long r_symndx;
2021 struct elf_link_hash_entry *h;
2022 Elf_Internal_Sym *sym;
2023 asection *sec;
2024 bfd_vma off;
2025 bfd_vma relocation;
2026 bfd_boolean unresolved_reloc;
2027 bfd_reloc_status_type r;
2028 unsigned int indx;
2029 int tls_type;
2030
2031 r_type = ELF32_R_TYPE (rel->r_info);
2032 if (r_type == R_386_GNU_VTINHERIT
2033 || r_type == R_386_GNU_VTENTRY)
2034 continue;
2035
2036 if ((indx = r_type) >= R_386_standard
2037 && ((indx = r_type - R_386_ext_offset) - R_386_standard
2038 >= R_386_ext - R_386_standard)
2039 && ((indx = r_type - R_386_tls_offset) - R_386_ext
2040 >= R_386_tls - R_386_ext))
2041 {
2042 bfd_set_error (bfd_error_bad_value);
2043 return FALSE;
2044 }
2045 howto = elf_howto_table + indx;
2046
2047 r_symndx = ELF32_R_SYM (rel->r_info);
2048
2049 if (info->relocatable)
2050 {
2051 bfd_vma val;
2052 bfd_byte *where;
2053
2054 /* This is a relocatable link. We don't have to change
2055 anything, unless the reloc is against a section symbol,
2056 in which case we have to adjust according to where the
2057 section symbol winds up in the output section. */
2058 if (r_symndx >= symtab_hdr->sh_info)
2059 continue;
2060
2061 sym = local_syms + r_symndx;
2062 if (ELF_ST_TYPE (sym->st_info) != STT_SECTION)
2063 continue;
2064
2065 sec = local_sections[r_symndx];
2066 val = sec->output_offset;
2067 if (val == 0)
2068 continue;
2069
2070 where = contents + rel->r_offset;
2071 switch (howto->size)
2072 {
2073 /* FIXME: overflow checks. */
2074 case 0:
2075 val += bfd_get_8 (input_bfd, where);
2076 bfd_put_8 (input_bfd, val, where);
2077 break;
2078 case 1:
2079 val += bfd_get_16 (input_bfd, where);
2080 bfd_put_16 (input_bfd, val, where);
2081 break;
2082 case 2:
2083 val += bfd_get_32 (input_bfd, where);
2084 bfd_put_32 (input_bfd, val, where);
2085 break;
2086 default:
2087 abort ();
2088 }
2089 continue;
2090 }
2091
2092 /* This is a final link. */
2093 h = NULL;
2094 sym = NULL;
2095 sec = NULL;
2096 unresolved_reloc = FALSE;
2097 if (r_symndx < symtab_hdr->sh_info)
2098 {
2099 sym = local_syms + r_symndx;
2100 sec = local_sections[r_symndx];
2101 relocation = (sec->output_section->vma
2102 + sec->output_offset
2103 + sym->st_value);
2104 if ((sec->flags & SEC_MERGE)
2105 && ELF_ST_TYPE (sym->st_info) == STT_SECTION)
2106 {
2107 asection *msec;
2108 bfd_vma addend;
2109 bfd_byte *where = contents + rel->r_offset;
2110
2111 switch (howto->size)
2112 {
2113 case 0:
2114 addend = bfd_get_8 (input_bfd, where);
2115 if (howto->pc_relative)
2116 {
2117 addend = (addend ^ 0x80) - 0x80;
2118 addend += 1;
2119 }
2120 break;
2121 case 1:
2122 addend = bfd_get_16 (input_bfd, where);
2123 if (howto->pc_relative)
2124 {
2125 addend = (addend ^ 0x8000) - 0x8000;
2126 addend += 2;
2127 }
2128 break;
2129 case 2:
2130 addend = bfd_get_32 (input_bfd, where);
2131 if (howto->pc_relative)
2132 {
2133 addend = (addend ^ 0x80000000) - 0x80000000;
2134 addend += 4;
2135 }
2136 break;
2137 default:
2138 abort ();
2139 }
2140
2141 msec = sec;
2142 addend = _bfd_elf_rel_local_sym (output_bfd, sym, &msec, addend);
2143 addend -= relocation;
2144 addend += msec->output_section->vma + msec->output_offset;
2145
2146 switch (howto->size)
2147 {
2148 case 0:
2149 /* FIXME: overflow checks. */
2150 if (howto->pc_relative)
2151 addend -= 1;
2152 bfd_put_8 (input_bfd, addend, where);
2153 break;
2154 case 1:
2155 if (howto->pc_relative)
2156 addend -= 2;
2157 bfd_put_16 (input_bfd, addend, where);
2158 break;
2159 case 2:
2160 if (howto->pc_relative)
2161 addend -= 4;
2162 bfd_put_32 (input_bfd, addend, where);
2163 break;
2164 }
2165 }
2166 }
2167 else
2168 {
2169 bfd_boolean warned;
2170
2171 RELOC_FOR_GLOBAL_SYMBOL (info, input_bfd, input_section, rel,
2172 r_symndx, symtab_hdr, sym_hashes,
2173 h, sec, relocation,
2174 unresolved_reloc, warned);
2175 }
2176
2177 switch (r_type)
2178 {
2179 case R_386_GOT32:
2180 /* Relocation is to the entry for this symbol in the global
2181 offset table. */
2182 if (htab->sgot == NULL)
2183 abort ();
2184
2185 if (h != NULL)
2186 {
2187 bfd_boolean dyn;
2188
2189 off = h->got.offset;
2190 dyn = htab->elf.dynamic_sections_created;
2191 if (! WILL_CALL_FINISH_DYNAMIC_SYMBOL (dyn, info->shared, h)
2192 || (info->shared
2193 && SYMBOL_REFERENCES_LOCAL (info, h))
2194 || (ELF_ST_VISIBILITY (h->other)
2195 && h->root.type == bfd_link_hash_undefweak))
2196 {
2197 /* This is actually a static link, or it is a
2198 -Bsymbolic link and the symbol is defined
2199 locally, or the symbol was forced to be local
2200 because of a version file. We must initialize
2201 this entry in the global offset table. Since the
2202 offset must always be a multiple of 4, we use the
2203 least significant bit to record whether we have
2204 initialized it already.
2205
2206 When doing a dynamic link, we create a .rel.got
2207 relocation entry to initialize the value. This
2208 is done in the finish_dynamic_symbol routine. */
2209 if ((off & 1) != 0)
2210 off &= ~1;
2211 else
2212 {
2213 bfd_put_32 (output_bfd, relocation,
2214 htab->sgot->contents + off);
2215 h->got.offset |= 1;
2216 }
2217 }
2218 else
2219 unresolved_reloc = FALSE;
2220 }
2221 else
2222 {
2223 if (local_got_offsets == NULL)
2224 abort ();
2225
2226 off = local_got_offsets[r_symndx];
2227
2228 /* The offset must always be a multiple of 4. We use
2229 the least significant bit to record whether we have
2230 already generated the necessary reloc. */
2231 if ((off & 1) != 0)
2232 off &= ~1;
2233 else
2234 {
2235 bfd_put_32 (output_bfd, relocation,
2236 htab->sgot->contents + off);
2237
2238 if (info->shared)
2239 {
2240 asection *s;
2241 Elf_Internal_Rela outrel;
2242 bfd_byte *loc;
2243
2244 s = htab->srelgot;
2245 if (s == NULL)
2246 abort ();
2247
2248 outrel.r_offset = (htab->sgot->output_section->vma
2249 + htab->sgot->output_offset
2250 + off);
2251 outrel.r_info = ELF32_R_INFO (0, R_386_RELATIVE);
2252 loc = s->contents;
2253 loc += s->reloc_count++ * sizeof (Elf32_External_Rel);
2254 bfd_elf32_swap_reloc_out (output_bfd, &outrel, loc);
2255 }
2256
2257 local_got_offsets[r_symndx] |= 1;
2258 }
2259 }
2260
2261 if (off >= (bfd_vma) -2)
2262 abort ();
2263
2264 relocation = htab->sgot->output_offset + off;
2265 break;
2266
2267 case R_386_GOTOFF:
2268 /* Relocation is relative to the start of the global offset
2269 table. */
2270
2271 /* Note that sgot->output_offset is not involved in this
2272 calculation. We always want the start of .got. If we
2273 defined _GLOBAL_OFFSET_TABLE in a different way, as is
2274 permitted by the ABI, we might have to change this
2275 calculation. */
2276 relocation -= htab->sgot->output_section->vma;
2277 break;
2278
2279 case R_386_GOTPC:
2280 /* Use global offset table as symbol value. */
2281 relocation = htab->sgot->output_section->vma;
2282 unresolved_reloc = FALSE;
2283 break;
2284
2285 case R_386_PLT32:
2286 /* Relocation is to the entry for this symbol in the
2287 procedure linkage table. */
2288
2289 /* Resolve a PLT32 reloc against a local symbol directly,
2290 without using the procedure linkage table. */
2291 if (h == NULL)
2292 break;
2293
2294 if (h->plt.offset == (bfd_vma) -1
2295 || htab->splt == NULL)
2296 {
2297 /* We didn't make a PLT entry for this symbol. This
2298 happens when statically linking PIC code, or when
2299 using -Bsymbolic. */
2300 break;
2301 }
2302
2303 relocation = (htab->splt->output_section->vma
2304 + htab->splt->output_offset
2305 + h->plt.offset);
2306 unresolved_reloc = FALSE;
2307 break;
2308
2309 case R_386_32:
2310 case R_386_PC32:
2311 /* r_symndx will be zero only for relocs against symbols
2312 from removed linkonce sections, or sections discarded by
2313 a linker script. */
2314 if (r_symndx == 0
2315 || (input_section->flags & SEC_ALLOC) == 0)
2316 break;
2317
2318 if ((info->shared
2319 && (h == NULL
2320 || ELF_ST_VISIBILITY (h->other) == STV_DEFAULT
2321 || h->root.type != bfd_link_hash_undefweak)
2322 && (r_type != R_386_PC32
2323 || !SYMBOL_CALLS_LOCAL (info, h)))
2324 || (ELIMINATE_COPY_RELOCS
2325 && !info->shared
2326 && h != NULL
2327 && h->dynindx != -1
2328 && (h->elf_link_hash_flags & ELF_LINK_NON_GOT_REF) == 0
2329 && (((h->elf_link_hash_flags
2330 & ELF_LINK_HASH_DEF_DYNAMIC) != 0
2331 && (h->elf_link_hash_flags
2332 & ELF_LINK_HASH_DEF_REGULAR) == 0)
2333 || h->root.type == bfd_link_hash_undefweak
2334 || h->root.type == bfd_link_hash_undefined)))
2335 {
2336 Elf_Internal_Rela outrel;
2337 bfd_byte *loc;
2338 bfd_boolean skip, relocate;
2339 asection *sreloc;
2340
2341 /* When generating a shared object, these relocations
2342 are copied into the output file to be resolved at run
2343 time. */
2344
2345 skip = FALSE;
2346 relocate = FALSE;
2347
2348 outrel.r_offset =
2349 _bfd_elf_section_offset (output_bfd, info, input_section,
2350 rel->r_offset);
2351 if (outrel.r_offset == (bfd_vma) -1)
2352 skip = TRUE;
2353 else if (outrel.r_offset == (bfd_vma) -2)
2354 skip = TRUE, relocate = TRUE;
2355 outrel.r_offset += (input_section->output_section->vma
2356 + input_section->output_offset);
2357
2358 if (skip)
2359 memset (&outrel, 0, sizeof outrel);
2360 else if (h != NULL
2361 && h->dynindx != -1
2362 && (r_type == R_386_PC32
2363 || !info->shared
2364 || !info->symbolic
2365 || (h->elf_link_hash_flags
2366 & ELF_LINK_HASH_DEF_REGULAR) == 0))
2367 outrel.r_info = ELF32_R_INFO (h->dynindx, r_type);
2368 else
2369 {
2370 /* This symbol is local, or marked to become local. */
2371 relocate = TRUE;
2372 outrel.r_info = ELF32_R_INFO (0, R_386_RELATIVE);
2373 }
2374
2375 sreloc = elf_section_data (input_section)->sreloc;
2376 if (sreloc == NULL)
2377 abort ();
2378
2379 loc = sreloc->contents;
2380 loc += sreloc->reloc_count++ * sizeof (Elf32_External_Rel);
2381 bfd_elf32_swap_reloc_out (output_bfd, &outrel, loc);
2382
2383 /* If this reloc is against an external symbol, we do
2384 not want to fiddle with the addend. Otherwise, we
2385 need to include the symbol value so that it becomes
2386 an addend for the dynamic reloc. */
2387 if (! relocate)
2388 continue;
2389 }
2390 break;
2391
2392 case R_386_TLS_IE:
2393 if (info->shared)
2394 {
2395 Elf_Internal_Rela outrel;
2396 bfd_byte *loc;
2397 asection *sreloc;
2398
2399 outrel.r_offset = rel->r_offset
2400 + input_section->output_section->vma
2401 + input_section->output_offset;
2402 outrel.r_info = ELF32_R_INFO (0, R_386_RELATIVE);
2403 sreloc = elf_section_data (input_section)->sreloc;
2404 if (sreloc == NULL)
2405 abort ();
2406 loc = sreloc->contents;
2407 loc += sreloc->reloc_count++ * sizeof (Elf32_External_Rel);
2408 bfd_elf32_swap_reloc_out (output_bfd, &outrel, loc);
2409 }
2410 /* Fall through */
2411
2412 case R_386_TLS_GD:
2413 case R_386_TLS_IE_32:
2414 case R_386_TLS_GOTIE:
2415 r_type = elf_i386_tls_transition (info, r_type, h == NULL);
2416 tls_type = GOT_UNKNOWN;
2417 if (h == NULL && local_got_offsets)
2418 tls_type = elf_i386_local_got_tls_type (input_bfd) [r_symndx];
2419 else if (h != NULL)
2420 {
2421 tls_type = elf_i386_hash_entry(h)->tls_type;
2422 if (!info->shared && h->dynindx == -1 && (tls_type & GOT_TLS_IE))
2423 r_type = R_386_TLS_LE_32;
2424 }
2425 if (tls_type == GOT_TLS_IE)
2426 tls_type = GOT_TLS_IE_NEG;
2427 if (r_type == R_386_TLS_GD)
2428 {
2429 if (tls_type == GOT_TLS_IE_POS)
2430 r_type = R_386_TLS_GOTIE;
2431 else if (tls_type & GOT_TLS_IE)
2432 r_type = R_386_TLS_IE_32;
2433 }
2434
2435 if (r_type == R_386_TLS_LE_32)
2436 {
2437 BFD_ASSERT (! unresolved_reloc);
2438 if (ELF32_R_TYPE (rel->r_info) == R_386_TLS_GD)
2439 {
2440 unsigned int val, type;
2441 bfd_vma roff;
2442
2443 /* GD->LE transition. */
2444 BFD_ASSERT (rel->r_offset >= 2);
2445 type = bfd_get_8 (input_bfd, contents + rel->r_offset - 2);
2446 BFD_ASSERT (type == 0x8d || type == 0x04);
2447 BFD_ASSERT (rel->r_offset + 9 <= input_section->_raw_size);
2448 BFD_ASSERT (bfd_get_8 (input_bfd,
2449 contents + rel->r_offset + 4)
2450 == 0xe8);
2451 BFD_ASSERT (rel + 1 < relend);
2452 BFD_ASSERT (ELF32_R_TYPE (rel[1].r_info) == R_386_PLT32);
2453 roff = rel->r_offset + 5;
2454 val = bfd_get_8 (input_bfd,
2455 contents + rel->r_offset - 1);
2456 if (type == 0x04)
2457 {
2458 /* leal foo(,%reg,1), %eax; call ___tls_get_addr
2459 Change it into:
2460 movl %gs:0, %eax; subl $foo@tpoff, %eax
2461 (6 byte form of subl). */
2462 BFD_ASSERT (rel->r_offset >= 3);
2463 BFD_ASSERT (bfd_get_8 (input_bfd,
2464 contents + rel->r_offset - 3)
2465 == 0x8d);
2466 BFD_ASSERT ((val & 0xc7) == 0x05 && val != (4 << 3));
2467 memcpy (contents + rel->r_offset - 3,
2468 "\x65\xa1\0\0\0\0\x81\xe8\0\0\0", 12);
2469 }
2470 else
2471 {
2472 BFD_ASSERT ((val & 0xf8) == 0x80 && (val & 7) != 4);
2473 if (rel->r_offset + 10 <= input_section->_raw_size
2474 && bfd_get_8 (input_bfd,
2475 contents + rel->r_offset + 9) == 0x90)
2476 {
2477 /* leal foo(%reg), %eax; call ___tls_get_addr; nop
2478 Change it into:
2479 movl %gs:0, %eax; subl $foo@tpoff, %eax
2480 (6 byte form of subl). */
2481 memcpy (contents + rel->r_offset - 2,
2482 "\x65\xa1\0\0\0\0\x81\xe8\0\0\0", 12);
2483 roff = rel->r_offset + 6;
2484 }
2485 else
2486 {
2487 /* leal foo(%reg), %eax; call ___tls_get_addr
2488 Change it into:
2489 movl %gs:0, %eax; subl $foo@tpoff, %eax
2490 (5 byte form of subl). */
2491 memcpy (contents + rel->r_offset - 2,
2492 "\x65\xa1\0\0\0\0\x2d\0\0\0", 11);
2493 }
2494 }
2495 bfd_put_32 (output_bfd, tpoff (info, relocation),
2496 contents + roff);
2497 /* Skip R_386_PLT32. */
2498 rel++;
2499 continue;
2500 }
2501 else if (ELF32_R_TYPE (rel->r_info) == R_386_TLS_IE)
2502 {
2503 unsigned int val, type;
2504
2505 /* IE->LE transition:
2506 Originally it can be one of:
2507 movl foo, %eax
2508 movl foo, %reg
2509 addl foo, %reg
2510 We change it into:
2511 movl $foo, %eax
2512 movl $foo, %reg
2513 addl $foo, %reg. */
2514 BFD_ASSERT (rel->r_offset >= 1);
2515 val = bfd_get_8 (input_bfd, contents + rel->r_offset - 1);
2516 BFD_ASSERT (rel->r_offset + 4 <= input_section->_raw_size);
2517 if (val == 0xa1)
2518 {
2519 /* movl foo, %eax. */
2520 bfd_put_8 (output_bfd, 0xb8,
2521 contents + rel->r_offset - 1);
2522 }
2523 else
2524 {
2525 BFD_ASSERT (rel->r_offset >= 2);
2526 type = bfd_get_8 (input_bfd,
2527 contents + rel->r_offset - 2);
2528 switch (type)
2529 {
2530 case 0x8b:
2531 /* movl */
2532 BFD_ASSERT ((val & 0xc7) == 0x05);
2533 bfd_put_8 (output_bfd, 0xc7,
2534 contents + rel->r_offset - 2);
2535 bfd_put_8 (output_bfd,
2536 0xc0 | ((val >> 3) & 7),
2537 contents + rel->r_offset - 1);
2538 break;
2539 case 0x03:
2540 /* addl */
2541 BFD_ASSERT ((val & 0xc7) == 0x05);
2542 bfd_put_8 (output_bfd, 0x81,
2543 contents + rel->r_offset - 2);
2544 bfd_put_8 (output_bfd,
2545 0xc0 | ((val >> 3) & 7),
2546 contents + rel->r_offset - 1);
2547 break;
2548 default:
2549 BFD_FAIL ();
2550 break;
2551 }
2552 }
2553 bfd_put_32 (output_bfd, -tpoff (info, relocation),
2554 contents + rel->r_offset);
2555 continue;
2556 }
2557 else
2558 {
2559 unsigned int val, type;
2560
2561 /* {IE_32,GOTIE}->LE transition:
2562 Originally it can be one of:
2563 subl foo(%reg1), %reg2
2564 movl foo(%reg1), %reg2
2565 addl foo(%reg1), %reg2
2566 We change it into:
2567 subl $foo, %reg2
2568 movl $foo, %reg2 (6 byte form)
2569 addl $foo, %reg2. */
2570 BFD_ASSERT (rel->r_offset >= 2);
2571 type = bfd_get_8 (input_bfd, contents + rel->r_offset - 2);
2572 val = bfd_get_8 (input_bfd, contents + rel->r_offset - 1);
2573 BFD_ASSERT (rel->r_offset + 4 <= input_section->_raw_size);
2574 BFD_ASSERT ((val & 0xc0) == 0x80 && (val & 7) != 4);
2575 if (type == 0x8b)
2576 {
2577 /* movl */
2578 bfd_put_8 (output_bfd, 0xc7,
2579 contents + rel->r_offset - 2);
2580 bfd_put_8 (output_bfd, 0xc0 | ((val >> 3) & 7),
2581 contents + rel->r_offset - 1);
2582 }
2583 else if (type == 0x2b)
2584 {
2585 /* subl */
2586 bfd_put_8 (output_bfd, 0x81,
2587 contents + rel->r_offset - 2);
2588 bfd_put_8 (output_bfd, 0xe8 | ((val >> 3) & 7),
2589 contents + rel->r_offset - 1);
2590 }
2591 else if (type == 0x03)
2592 {
2593 /* addl */
2594 bfd_put_8 (output_bfd, 0x81,
2595 contents + rel->r_offset - 2);
2596 bfd_put_8 (output_bfd, 0xc0 | ((val >> 3) & 7),
2597 contents + rel->r_offset - 1);
2598 }
2599 else
2600 BFD_FAIL ();
2601 if (ELF32_R_TYPE (rel->r_info) == R_386_TLS_GOTIE)
2602 bfd_put_32 (output_bfd, -tpoff (info, relocation),
2603 contents + rel->r_offset);
2604 else
2605 bfd_put_32 (output_bfd, tpoff (info, relocation),
2606 contents + rel->r_offset);
2607 continue;
2608 }
2609 }
2610
2611 if (htab->sgot == NULL)
2612 abort ();
2613
2614 if (h != NULL)
2615 off = h->got.offset;
2616 else
2617 {
2618 if (local_got_offsets == NULL)
2619 abort ();
2620
2621 off = local_got_offsets[r_symndx];
2622 }
2623
2624 if ((off & 1) != 0)
2625 off &= ~1;
2626 else
2627 {
2628 Elf_Internal_Rela outrel;
2629 bfd_byte *loc;
2630 int dr_type, indx;
2631
2632 if (htab->srelgot == NULL)
2633 abort ();
2634
2635 outrel.r_offset = (htab->sgot->output_section->vma
2636 + htab->sgot->output_offset + off);
2637
2638 indx = h && h->dynindx != -1 ? h->dynindx : 0;
2639 if (r_type == R_386_TLS_GD)
2640 dr_type = R_386_TLS_DTPMOD32;
2641 else if (tls_type == GOT_TLS_IE_POS)
2642 dr_type = R_386_TLS_TPOFF;
2643 else
2644 dr_type = R_386_TLS_TPOFF32;
2645 if (dr_type == R_386_TLS_TPOFF && indx == 0)
2646 bfd_put_32 (output_bfd, relocation - dtpoff_base (info),
2647 htab->sgot->contents + off);
2648 else if (dr_type == R_386_TLS_TPOFF32 && indx == 0)
2649 bfd_put_32 (output_bfd, dtpoff_base (info) - relocation,
2650 htab->sgot->contents + off);
2651 else
2652 bfd_put_32 (output_bfd, 0,
2653 htab->sgot->contents + off);
2654 outrel.r_info = ELF32_R_INFO (indx, dr_type);
2655 loc = htab->srelgot->contents;
2656 loc += htab->srelgot->reloc_count++ * sizeof (Elf32_External_Rel);
2657 bfd_elf32_swap_reloc_out (output_bfd, &outrel, loc);
2658
2659 if (r_type == R_386_TLS_GD)
2660 {
2661 if (indx == 0)
2662 {
2663 BFD_ASSERT (! unresolved_reloc);
2664 bfd_put_32 (output_bfd,
2665 relocation - dtpoff_base (info),
2666 htab->sgot->contents + off + 4);
2667 }
2668 else
2669 {
2670 bfd_put_32 (output_bfd, 0,
2671 htab->sgot->contents + off + 4);
2672 outrel.r_info = ELF32_R_INFO (indx,
2673 R_386_TLS_DTPOFF32);
2674 outrel.r_offset += 4;
2675 htab->srelgot->reloc_count++;
2676 loc += sizeof (Elf32_External_Rel);
2677 bfd_elf32_swap_reloc_out (output_bfd, &outrel, loc);
2678 }
2679 }
2680 else if (tls_type == GOT_TLS_IE_BOTH)
2681 {
2682 bfd_put_32 (output_bfd,
2683 indx == 0 ? relocation - dtpoff_base (info) : 0,
2684 htab->sgot->contents + off + 4);
2685 outrel.r_info = ELF32_R_INFO (indx, R_386_TLS_TPOFF);
2686 outrel.r_offset += 4;
2687 htab->srelgot->reloc_count++;
2688 loc += sizeof (Elf32_External_Rel);
2689 bfd_elf32_swap_reloc_out (output_bfd, &outrel, loc);
2690 }
2691
2692 if (h != NULL)
2693 h->got.offset |= 1;
2694 else
2695 local_got_offsets[r_symndx] |= 1;
2696 }
2697
2698 if (off >= (bfd_vma) -2)
2699 abort ();
2700 if (r_type == ELF32_R_TYPE (rel->r_info))
2701 {
2702 relocation = htab->sgot->output_offset + off;
2703 if ((r_type == R_386_TLS_IE || r_type == R_386_TLS_GOTIE)
2704 && tls_type == GOT_TLS_IE_BOTH)
2705 relocation += 4;
2706 if (r_type == R_386_TLS_IE)
2707 relocation += htab->sgot->output_section->vma;
2708 unresolved_reloc = FALSE;
2709 }
2710 else
2711 {
2712 unsigned int val, type;
2713 bfd_vma roff;
2714
2715 /* GD->IE transition. */
2716 BFD_ASSERT (rel->r_offset >= 2);
2717 type = bfd_get_8 (input_bfd, contents + rel->r_offset - 2);
2718 BFD_ASSERT (type == 0x8d || type == 0x04);
2719 BFD_ASSERT (rel->r_offset + 9 <= input_section->_raw_size);
2720 BFD_ASSERT (bfd_get_8 (input_bfd, contents + rel->r_offset + 4)
2721 == 0xe8);
2722 BFD_ASSERT (rel + 1 < relend);
2723 BFD_ASSERT (ELF32_R_TYPE (rel[1].r_info) == R_386_PLT32);
2724 roff = rel->r_offset - 3;
2725 val = bfd_get_8 (input_bfd, contents + rel->r_offset - 1);
2726 if (type == 0x04)
2727 {
2728 /* leal foo(,%reg,1), %eax; call ___tls_get_addr
2729 Change it into:
2730 movl %gs:0, %eax; subl $foo@gottpoff(%reg), %eax. */
2731 BFD_ASSERT (rel->r_offset >= 3);
2732 BFD_ASSERT (bfd_get_8 (input_bfd,
2733 contents + rel->r_offset - 3)
2734 == 0x8d);
2735 BFD_ASSERT ((val & 0xc7) == 0x05 && val != (4 << 3));
2736 val >>= 3;
2737 }
2738 else
2739 {
2740 /* leal foo(%reg), %eax; call ___tls_get_addr; nop
2741 Change it into:
2742 movl %gs:0, %eax; subl $foo@gottpoff(%reg), %eax. */
2743 BFD_ASSERT (rel->r_offset + 10 <= input_section->_raw_size);
2744 BFD_ASSERT ((val & 0xf8) == 0x80 && (val & 7) != 4);
2745 BFD_ASSERT (bfd_get_8 (input_bfd,
2746 contents + rel->r_offset + 9)
2747 == 0x90);
2748 roff = rel->r_offset - 2;
2749 }
2750 memcpy (contents + roff,
2751 "\x65\xa1\0\0\0\0\x2b\x80\0\0\0", 12);
2752 contents[roff + 7] = 0x80 | (val & 7);
2753 /* If foo is used only with foo@gotntpoff(%reg) and
2754 foo@indntpoff, but not with foo@gottpoff(%reg), change
2755 subl $foo@gottpoff(%reg), %eax
2756 into:
2757 addl $foo@gotntpoff(%reg), %eax. */
2758 if (r_type == R_386_TLS_GOTIE)
2759 {
2760 contents[roff + 6] = 0x03;
2761 if (tls_type == GOT_TLS_IE_BOTH)
2762 off += 4;
2763 }
2764 bfd_put_32 (output_bfd, htab->sgot->output_offset + off,
2765 contents + roff + 8);
2766 /* Skip R_386_PLT32. */
2767 rel++;
2768 continue;
2769 }
2770 break;
2771
2772 case R_386_TLS_LDM:
2773 if (! info->shared)
2774 {
2775 unsigned int val;
2776
2777 /* LD->LE transition:
2778 Ensure it is:
2779 leal foo(%reg), %eax; call ___tls_get_addr.
2780 We change it into:
2781 movl %gs:0, %eax; nop; leal 0(%esi,1), %esi. */
2782 BFD_ASSERT (rel->r_offset >= 2);
2783 BFD_ASSERT (bfd_get_8 (input_bfd, contents + rel->r_offset - 2)
2784 == 0x8d);
2785 val = bfd_get_8 (input_bfd, contents + rel->r_offset - 1);
2786 BFD_ASSERT ((val & 0xf8) == 0x80 && (val & 7) != 4);
2787 BFD_ASSERT (rel->r_offset + 9 <= input_section->_raw_size);
2788 BFD_ASSERT (bfd_get_8 (input_bfd, contents + rel->r_offset + 4)
2789 == 0xe8);
2790 BFD_ASSERT (rel + 1 < relend);
2791 BFD_ASSERT (ELF32_R_TYPE (rel[1].r_info) == R_386_PLT32);
2792 memcpy (contents + rel->r_offset - 2,
2793 "\x65\xa1\0\0\0\0\x90\x8d\x74\x26", 11);
2794 /* Skip R_386_PLT32. */
2795 rel++;
2796 continue;
2797 }
2798
2799 if (htab->sgot == NULL)
2800 abort ();
2801
2802 off = htab->tls_ldm_got.offset;
2803 if (off & 1)
2804 off &= ~1;
2805 else
2806 {
2807 Elf_Internal_Rela outrel;
2808 bfd_byte *loc;
2809
2810 if (htab->srelgot == NULL)
2811 abort ();
2812
2813 outrel.r_offset = (htab->sgot->output_section->vma
2814 + htab->sgot->output_offset + off);
2815
2816 bfd_put_32 (output_bfd, 0,
2817 htab->sgot->contents + off);
2818 bfd_put_32 (output_bfd, 0,
2819 htab->sgot->contents + off + 4);
2820 outrel.r_info = ELF32_R_INFO (0, R_386_TLS_DTPMOD32);
2821 loc = htab->srelgot->contents;
2822 loc += htab->srelgot->reloc_count++ * sizeof (Elf32_External_Rel);
2823 bfd_elf32_swap_reloc_out (output_bfd, &outrel, loc);
2824 htab->tls_ldm_got.offset |= 1;
2825 }
2826 relocation = htab->sgot->output_offset + off;
2827 unresolved_reloc = FALSE;
2828 break;
2829
2830 case R_386_TLS_LDO_32:
2831 if (info->shared || (input_section->flags & SEC_CODE) == 0)
2832 relocation -= dtpoff_base (info);
2833 else
2834 /* When converting LDO to LE, we must negate. */
2835 relocation = -tpoff (info, relocation);
2836 break;
2837
2838 case R_386_TLS_LE_32:
2839 case R_386_TLS_LE:
2840 if (info->shared)
2841 {
2842 Elf_Internal_Rela outrel;
2843 asection *sreloc;
2844 bfd_byte *loc;
2845 int indx;
2846
2847 outrel.r_offset = rel->r_offset
2848 + input_section->output_section->vma
2849 + input_section->output_offset;
2850 if (h != NULL && h->dynindx != -1)
2851 indx = h->dynindx;
2852 else
2853 indx = 0;
2854 if (r_type == R_386_TLS_LE_32)
2855 outrel.r_info = ELF32_R_INFO (indx, R_386_TLS_TPOFF32);
2856 else
2857 outrel.r_info = ELF32_R_INFO (indx, R_386_TLS_TPOFF);
2858 sreloc = elf_section_data (input_section)->sreloc;
2859 if (sreloc == NULL)
2860 abort ();
2861 loc = sreloc->contents;
2862 loc += sreloc->reloc_count++ * sizeof (Elf32_External_Rel);
2863 bfd_elf32_swap_reloc_out (output_bfd, &outrel, loc);
2864 if (indx)
2865 continue;
2866 else if (r_type == R_386_TLS_LE_32)
2867 relocation = dtpoff_base (info) - relocation;
2868 else
2869 relocation -= dtpoff_base (info);
2870 }
2871 else if (r_type == R_386_TLS_LE_32)
2872 relocation = tpoff (info, relocation);
2873 else
2874 relocation = -tpoff (info, relocation);
2875 break;
2876
2877 default:
2878 break;
2879 }
2880
2881 /* Dynamic relocs are not propagated for SEC_DEBUGGING sections
2882 because such sections are not SEC_ALLOC and thus ld.so will
2883 not process them. */
2884 if (unresolved_reloc
2885 && !((input_section->flags & SEC_DEBUGGING) != 0
2886 && (h->elf_link_hash_flags & ELF_LINK_HASH_DEF_DYNAMIC) != 0))
2887 {
2888 (*_bfd_error_handler)
2889 (_("%s(%s+0x%lx): unresolvable relocation against symbol `%s'"),
2890 bfd_archive_filename (input_bfd),
2891 bfd_get_section_name (input_bfd, input_section),
2892 (long) rel->r_offset,
2893 h->root.root.string);
2894 return FALSE;
2895 }
2896
2897 r = _bfd_final_link_relocate (howto, input_bfd, input_section,
2898 contents, rel->r_offset,
2899 relocation, 0);
2900
2901 if (r != bfd_reloc_ok)
2902 {
2903 const char *name;
2904
2905 if (h != NULL)
2906 name = h->root.root.string;
2907 else
2908 {
2909 name = bfd_elf_string_from_elf_section (input_bfd,
2910 symtab_hdr->sh_link,
2911 sym->st_name);
2912 if (name == NULL)
2913 return FALSE;
2914 if (*name == '\0')
2915 name = bfd_section_name (input_bfd, sec);
2916 }
2917
2918 if (r == bfd_reloc_overflow)
2919 {
2920 if (! ((*info->callbacks->reloc_overflow)
2921 (info, name, howto->name, 0,
2922 input_bfd, input_section, rel->r_offset)))
2923 return FALSE;
2924 }
2925 else
2926 {
2927 (*_bfd_error_handler)
2928 (_("%s(%s+0x%lx): reloc against `%s': error %d"),
2929 bfd_archive_filename (input_bfd),
2930 bfd_get_section_name (input_bfd, input_section),
2931 (long) rel->r_offset, name, (int) r);
2932 return FALSE;
2933 }
2934 }
2935 }
2936
2937 return TRUE;
2938 }
2939
2940 /* Finish up dynamic symbol handling. We set the contents of various
2941 dynamic sections here. */
2942
2943 static bfd_boolean
elf_i386_finish_dynamic_symbol(bfd * output_bfd,struct bfd_link_info * info,struct elf_link_hash_entry * h,Elf_Internal_Sym * sym)2944 elf_i386_finish_dynamic_symbol (bfd *output_bfd,
2945 struct bfd_link_info *info,
2946 struct elf_link_hash_entry *h,
2947 Elf_Internal_Sym *sym)
2948 {
2949 struct elf_i386_link_hash_table *htab;
2950
2951 htab = elf_i386_hash_table (info);
2952
2953 if (h->plt.offset != (bfd_vma) -1)
2954 {
2955 bfd_vma plt_index;
2956 bfd_vma got_offset;
2957 Elf_Internal_Rela rel;
2958 bfd_byte *loc;
2959
2960 /* This symbol has an entry in the procedure linkage table. Set
2961 it up. */
2962
2963 if (h->dynindx == -1
2964 || htab->splt == NULL
2965 || htab->sgotplt == NULL
2966 || htab->srelplt == NULL)
2967 abort ();
2968
2969 /* Get the index in the procedure linkage table which
2970 corresponds to this symbol. This is the index of this symbol
2971 in all the symbols for which we are making plt entries. The
2972 first entry in the procedure linkage table is reserved. */
2973 plt_index = h->plt.offset / PLT_ENTRY_SIZE - 1;
2974
2975 /* Get the offset into the .got table of the entry that
2976 corresponds to this function. Each .got entry is 4 bytes.
2977 The first three are reserved. */
2978 got_offset = (plt_index + 3) * 4;
2979
2980 /* Fill in the entry in the procedure linkage table. */
2981 if (! info->shared)
2982 {
2983 memcpy (htab->splt->contents + h->plt.offset, elf_i386_plt_entry,
2984 PLT_ENTRY_SIZE);
2985 bfd_put_32 (output_bfd,
2986 (htab->sgotplt->output_section->vma
2987 + htab->sgotplt->output_offset
2988 + got_offset),
2989 htab->splt->contents + h->plt.offset + 2);
2990 }
2991 else
2992 {
2993 memcpy (htab->splt->contents + h->plt.offset, elf_i386_pic_plt_entry,
2994 PLT_ENTRY_SIZE);
2995 bfd_put_32 (output_bfd, got_offset,
2996 htab->splt->contents + h->plt.offset + 2);
2997 }
2998
2999 bfd_put_32 (output_bfd, plt_index * sizeof (Elf32_External_Rel),
3000 htab->splt->contents + h->plt.offset + 7);
3001 bfd_put_32 (output_bfd, - (h->plt.offset + PLT_ENTRY_SIZE),
3002 htab->splt->contents + h->plt.offset + 12);
3003
3004 /* Fill in the entry in the global offset table. */
3005 bfd_put_32 (output_bfd,
3006 (htab->splt->output_section->vma
3007 + htab->splt->output_offset
3008 + h->plt.offset
3009 + 6),
3010 htab->sgotplt->contents + got_offset);
3011
3012 /* Fill in the entry in the .rel.plt section. */
3013 rel.r_offset = (htab->sgotplt->output_section->vma
3014 + htab->sgotplt->output_offset
3015 + got_offset);
3016 rel.r_info = ELF32_R_INFO (h->dynindx, R_386_JUMP_SLOT);
3017 loc = htab->srelplt->contents + plt_index * sizeof (Elf32_External_Rel);
3018 bfd_elf32_swap_reloc_out (output_bfd, &rel, loc);
3019
3020 if ((h->elf_link_hash_flags & ELF_LINK_HASH_DEF_REGULAR) == 0)
3021 {
3022 /* Mark the symbol as undefined, rather than as defined in
3023 the .plt section. Leave the value if there were any
3024 relocations where pointer equality matters (this is a clue
3025 for the dynamic linker, to make function pointer
3026 comparisons work between an application and shared
3027 library), otherwise set it to zero. If a function is only
3028 called from a binary, there is no need to slow down
3029 shared libraries because of that. */
3030 sym->st_shndx = SHN_UNDEF;
3031 if ((h->elf_link_hash_flags & ELF_LINK_POINTER_EQUALITY_NEEDED) == 0)
3032 sym->st_value = 0;
3033 }
3034 }
3035
3036 if (h->got.offset != (bfd_vma) -1
3037 && elf_i386_hash_entry(h)->tls_type != GOT_TLS_GD
3038 && (elf_i386_hash_entry(h)->tls_type & GOT_TLS_IE) == 0)
3039 {
3040 Elf_Internal_Rela rel;
3041 bfd_byte *loc;
3042
3043 /* This symbol has an entry in the global offset table. Set it
3044 up. */
3045
3046 if (htab->sgot == NULL || htab->srelgot == NULL)
3047 abort ();
3048
3049 rel.r_offset = (htab->sgot->output_section->vma
3050 + htab->sgot->output_offset
3051 + (h->got.offset & ~(bfd_vma) 1));
3052
3053 /* If this is a static link, or it is a -Bsymbolic link and the
3054 symbol is defined locally or was forced to be local because
3055 of a version file, we just want to emit a RELATIVE reloc.
3056 The entry in the global offset table will already have been
3057 initialized in the relocate_section function. */
3058 if (info->shared
3059 && SYMBOL_REFERENCES_LOCAL (info, h))
3060 {
3061 BFD_ASSERT((h->got.offset & 1) != 0);
3062 rel.r_info = ELF32_R_INFO (0, R_386_RELATIVE);
3063 }
3064 else
3065 {
3066 BFD_ASSERT((h->got.offset & 1) == 0);
3067 bfd_put_32 (output_bfd, (bfd_vma) 0,
3068 htab->sgot->contents + h->got.offset);
3069 rel.r_info = ELF32_R_INFO (h->dynindx, R_386_GLOB_DAT);
3070 }
3071
3072 loc = htab->srelgot->contents;
3073 loc += htab->srelgot->reloc_count++ * sizeof (Elf32_External_Rel);
3074 bfd_elf32_swap_reloc_out (output_bfd, &rel, loc);
3075 }
3076
3077 if ((h->elf_link_hash_flags & ELF_LINK_HASH_NEEDS_COPY) != 0)
3078 {
3079 Elf_Internal_Rela rel;
3080 bfd_byte *loc;
3081
3082 /* This symbol needs a copy reloc. Set it up. */
3083
3084 if (h->dynindx == -1
3085 || (h->root.type != bfd_link_hash_defined
3086 && h->root.type != bfd_link_hash_defweak)
3087 || htab->srelbss == NULL)
3088 abort ();
3089
3090 rel.r_offset = (h->root.u.def.value
3091 + h->root.u.def.section->output_section->vma
3092 + h->root.u.def.section->output_offset);
3093 rel.r_info = ELF32_R_INFO (h->dynindx, R_386_COPY);
3094 loc = htab->srelbss->contents;
3095 loc += htab->srelbss->reloc_count++ * sizeof (Elf32_External_Rel);
3096 bfd_elf32_swap_reloc_out (output_bfd, &rel, loc);
3097 }
3098
3099 /* Mark _DYNAMIC and _GLOBAL_OFFSET_TABLE_ as absolute. */
3100 if (strcmp (h->root.root.string, "_DYNAMIC") == 0
3101 || strcmp (h->root.root.string, "_GLOBAL_OFFSET_TABLE_") == 0)
3102 sym->st_shndx = SHN_ABS;
3103
3104 return TRUE;
3105 }
3106
3107 /* Used to decide how to sort relocs in an optimal manner for the
3108 dynamic linker, before writing them out. */
3109
3110 static enum elf_reloc_type_class
elf_i386_reloc_type_class(const Elf_Internal_Rela * rela)3111 elf_i386_reloc_type_class (const Elf_Internal_Rela *rela)
3112 {
3113 switch (ELF32_R_TYPE (rela->r_info))
3114 {
3115 case R_386_RELATIVE:
3116 return reloc_class_relative;
3117 case R_386_JUMP_SLOT:
3118 return reloc_class_plt;
3119 case R_386_COPY:
3120 return reloc_class_copy;
3121 default:
3122 return reloc_class_normal;
3123 }
3124 }
3125
3126 /* Finish up the dynamic sections. */
3127
3128 static bfd_boolean
elf_i386_finish_dynamic_sections(bfd * output_bfd,struct bfd_link_info * info)3129 elf_i386_finish_dynamic_sections (bfd *output_bfd,
3130 struct bfd_link_info *info)
3131 {
3132 struct elf_i386_link_hash_table *htab;
3133 bfd *dynobj;
3134 asection *sdyn;
3135
3136 htab = elf_i386_hash_table (info);
3137 dynobj = htab->elf.dynobj;
3138 sdyn = bfd_get_section_by_name (dynobj, ".dynamic");
3139
3140 if (htab->elf.dynamic_sections_created)
3141 {
3142 Elf32_External_Dyn *dyncon, *dynconend;
3143
3144 if (sdyn == NULL || htab->sgot == NULL)
3145 abort ();
3146
3147 dyncon = (Elf32_External_Dyn *) sdyn->contents;
3148 dynconend = (Elf32_External_Dyn *) (sdyn->contents + sdyn->_raw_size);
3149 for (; dyncon < dynconend; dyncon++)
3150 {
3151 Elf_Internal_Dyn dyn;
3152 asection *s;
3153
3154 bfd_elf32_swap_dyn_in (dynobj, dyncon, &dyn);
3155
3156 switch (dyn.d_tag)
3157 {
3158 default:
3159 continue;
3160
3161 case DT_PLTGOT:
3162 dyn.d_un.d_ptr = htab->sgot->output_section->vma;
3163 break;
3164
3165 case DT_JMPREL:
3166 s = htab->srelplt;
3167 dyn.d_un.d_ptr = s->output_section->vma + s->output_offset;
3168 break;
3169
3170 case DT_PLTRELSZ:
3171 s = htab->srelplt;
3172 dyn.d_un.d_val = s->_raw_size;
3173 break;
3174
3175 case DT_RELSZ:
3176 /* My reading of the SVR4 ABI indicates that the
3177 procedure linkage table relocs (DT_JMPREL) should be
3178 included in the overall relocs (DT_REL). This is
3179 what Solaris does. However, UnixWare can not handle
3180 that case. Therefore, we override the DT_RELSZ entry
3181 here to make it not include the JMPREL relocs. */
3182 s = htab->srelplt;
3183 if (s == NULL)
3184 continue;
3185 dyn.d_un.d_val -= s->_raw_size;
3186 break;
3187
3188 case DT_REL:
3189 /* We may not be using the standard ELF linker script.
3190 If .rel.plt is the first .rel section, we adjust
3191 DT_REL to not include it. */
3192 s = htab->srelplt;
3193 if (s == NULL)
3194 continue;
3195 if (dyn.d_un.d_ptr != s->output_section->vma + s->output_offset)
3196 continue;
3197 dyn.d_un.d_ptr += s->_raw_size;
3198 break;
3199 }
3200
3201 bfd_elf32_swap_dyn_out (output_bfd, &dyn, dyncon);
3202 }
3203
3204 /* Fill in the first entry in the procedure linkage table. */
3205 if (htab->splt && htab->splt->_raw_size > 0)
3206 {
3207 if (info->shared)
3208 memcpy (htab->splt->contents,
3209 elf_i386_pic_plt0_entry, PLT_ENTRY_SIZE);
3210 else
3211 {
3212 memcpy (htab->splt->contents,
3213 elf_i386_plt0_entry, PLT_ENTRY_SIZE);
3214 bfd_put_32 (output_bfd,
3215 (htab->sgotplt->output_section->vma
3216 + htab->sgotplt->output_offset
3217 + 4),
3218 htab->splt->contents + 2);
3219 bfd_put_32 (output_bfd,
3220 (htab->sgotplt->output_section->vma
3221 + htab->sgotplt->output_offset
3222 + 8),
3223 htab->splt->contents + 8);
3224 }
3225
3226 /* UnixWare sets the entsize of .plt to 4, although that doesn't
3227 really seem like the right value. */
3228 elf_section_data (htab->splt->output_section)
3229 ->this_hdr.sh_entsize = 4;
3230 }
3231 }
3232
3233 if (htab->sgotplt)
3234 {
3235 /* Fill in the first three entries in the global offset table. */
3236 if (htab->sgotplt->_raw_size > 0)
3237 {
3238 bfd_put_32 (output_bfd,
3239 (sdyn == NULL ? 0
3240 : sdyn->output_section->vma + sdyn->output_offset),
3241 htab->sgotplt->contents);
3242 bfd_put_32 (output_bfd, 0, htab->sgotplt->contents + 4);
3243 bfd_put_32 (output_bfd, 0, htab->sgotplt->contents + 8);
3244 }
3245
3246 elf_section_data (htab->sgotplt->output_section)->this_hdr.sh_entsize = 4;
3247 }
3248 return TRUE;
3249 }
3250
3251 #define TARGET_LITTLE_SYM bfd_elf32_i386_vec
3252 #define TARGET_LITTLE_NAME "elf32-i386"
3253 #define ELF_ARCH bfd_arch_i386
3254 #define ELF_MACHINE_CODE EM_386
3255 #define ELF_MAXPAGESIZE 0x1000
3256
3257 #define elf_backend_can_gc_sections 1
3258 #define elf_backend_can_refcount 1
3259 #define elf_backend_want_got_plt 1
3260 #define elf_backend_plt_readonly 1
3261 #define elf_backend_want_plt_sym 0
3262 #define elf_backend_got_header_size 12
3263
3264 /* Support RELA for objdump of prelink objects. */
3265 #define elf_info_to_howto elf_i386_info_to_howto_rel
3266 #define elf_info_to_howto_rel elf_i386_info_to_howto_rel
3267
3268 #define bfd_elf32_mkobject elf_i386_mkobject
3269
3270 #define bfd_elf32_bfd_is_local_label_name elf_i386_is_local_label_name
3271 #define bfd_elf32_bfd_link_hash_table_create elf_i386_link_hash_table_create
3272 #define bfd_elf32_bfd_reloc_type_lookup elf_i386_reloc_type_lookup
3273
3274 #define elf_backend_adjust_dynamic_symbol elf_i386_adjust_dynamic_symbol
3275 #define elf_backend_check_relocs elf_i386_check_relocs
3276 #define elf_backend_copy_indirect_symbol elf_i386_copy_indirect_symbol
3277 #define elf_backend_create_dynamic_sections elf_i386_create_dynamic_sections
3278 #define elf_backend_fake_sections elf_i386_fake_sections
3279 #define elf_backend_finish_dynamic_sections elf_i386_finish_dynamic_sections
3280 #define elf_backend_finish_dynamic_symbol elf_i386_finish_dynamic_symbol
3281 #define elf_backend_gc_mark_hook elf_i386_gc_mark_hook
3282 #define elf_backend_gc_sweep_hook elf_i386_gc_sweep_hook
3283 #define elf_backend_grok_prstatus elf_i386_grok_prstatus
3284 #define elf_backend_grok_psinfo elf_i386_grok_psinfo
3285 #define elf_backend_reloc_type_class elf_i386_reloc_type_class
3286 #define elf_backend_relocate_section elf_i386_relocate_section
3287 #define elf_backend_size_dynamic_sections elf_i386_size_dynamic_sections
3288
3289 #include "elf32-target.h"
3290
3291 /* FreeBSD support. */
3292
3293 #undef TARGET_LITTLE_SYM
3294 #define TARGET_LITTLE_SYM bfd_elf32_i386_freebsd_vec
3295 #undef TARGET_LITTLE_NAME
3296 #define TARGET_LITTLE_NAME "elf32-i386-freebsd"
3297
3298 /* The kernel recognizes executables as valid only if they carry a
3299 "FreeBSD" label in the ELF header. So we put this label on all
3300 executables and (for simplicity) also all other object files. */
3301
3302 static void
elf_i386_post_process_headers(bfd * abfd,struct bfd_link_info * info ATTRIBUTE_UNUSED)3303 elf_i386_post_process_headers (bfd *abfd,
3304 struct bfd_link_info *info ATTRIBUTE_UNUSED)
3305 {
3306 Elf_Internal_Ehdr *i_ehdrp;
3307
3308 i_ehdrp = elf_elfheader (abfd);
3309
3310 /* Put an ABI label supported by FreeBSD >= 4.1. */
3311 i_ehdrp->e_ident[EI_OSABI] = ELFOSABI_FREEBSD;
3312 #ifdef OLD_FREEBSD_ABI_LABEL
3313 /* The ABI label supported by FreeBSD <= 4.0 is quite nonstandard. */
3314 memcpy (&i_ehdrp->e_ident[EI_ABIVERSION], "FreeBSD", 8);
3315 #endif
3316 }
3317
3318 #undef elf_backend_post_process_headers
3319 #define elf_backend_post_process_headers elf_i386_post_process_headers
3320 #undef elf32_bed
3321 #define elf32_bed elf32_i386_fbsd_bed
3322
3323 #include "elf32-target.h"
3324