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1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * linux/arch/arm/kernel/module.c
4 *
5 * Copyright (C) 2002 Russell King.
6 * Modified for nommu by Hyok S. Choi
7 *
8 * Module allocation method suggested by Andi Kleen.
9 */
10#include <linux/module.h>
11#include <linux/moduleloader.h>
12#include <linux/kernel.h>
13#include <linux/mm.h>
14#include <linux/elf.h>
15#include <linux/vmalloc.h>
16#include <linux/fs.h>
17#include <linux/string.h>
18#include <linux/gfp.h>
19
20#include <asm/sections.h>
21#include <asm/smp_plat.h>
22#include <asm/unwind.h>
23#include <asm/opcodes.h>
24
25#ifdef CONFIG_XIP_KERNEL
26/*
27 * The XIP kernel text is mapped in the module area for modules and
28 * some other stuff to work without any indirect relocations.
29 * MODULES_VADDR is redefined here and not in asm/memory.h to avoid
30 * recompiling the whole kernel when CONFIG_XIP_KERNEL is turned on/off.
31 */
32#undef MODULES_VADDR
33#define MODULES_VADDR (((unsigned long)_exiprom + ~PMD_MASK) & PMD_MASK)
34#endif
35
36#ifdef CONFIG_MMU
37void *module_alloc(unsigned long size)
38{
39 gfp_t gfp_mask = GFP_KERNEL;
40 void *p;
41
42 /* Silence the initial allocation */
43 if (IS_ENABLED(CONFIG_ARM_MODULE_PLTS))
44 gfp_mask |= __GFP_NOWARN;
45
46 p = __vmalloc_node_range(size, 1, MODULES_VADDR, MODULES_END,
47 gfp_mask, PAGE_KERNEL_EXEC, 0, NUMA_NO_NODE,
48 __builtin_return_address(0));
49 if (!IS_ENABLED(CONFIG_ARM_MODULE_PLTS) || p)
50 return p;
51 return __vmalloc_node_range(size, 1, VMALLOC_START, VMALLOC_END,
52 GFP_KERNEL, PAGE_KERNEL_EXEC, 0, NUMA_NO_NODE,
53 __builtin_return_address(0));
54}
55#endif
56
57bool module_init_section(const char *name)
58{
59 return strstarts(name, ".init") ||
60 strstarts(name, ".ARM.extab.init") ||
61 strstarts(name, ".ARM.exidx.init");
62}
63
64bool module_exit_section(const char *name)
65{
66 return strstarts(name, ".exit") ||
67 strstarts(name, ".ARM.extab.exit") ||
68 strstarts(name, ".ARM.exidx.exit");
69}
70
71#ifdef CONFIG_ARM_HAS_GROUP_RELOCS
72/*
73 * This implements the partitioning algorithm for group relocations as
74 * documented in the ARM AArch32 ELF psABI (IHI 0044).
75 *
76 * A single PC-relative symbol reference is divided in up to 3 add or subtract
77 * operations, where the final one could be incorporated into a load/store
78 * instruction with immediate offset. E.g.,
79 *
80 * ADD Rd, PC, #... or ADD Rd, PC, #...
81 * ADD Rd, Rd, #... ADD Rd, Rd, #...
82 * LDR Rd, [Rd, #...] ADD Rd, Rd, #...
83 *
84 * The latter has a guaranteed range of only 16 MiB (3x8 == 24 bits), so it is
85 * of limited use in the kernel. However, the ADD/ADD/LDR combo has a range of
86 * -/+ 256 MiB, (2x8 + 12 == 28 bits), which means it has sufficient range for
87 * any in-kernel symbol reference (unless module PLTs are being used).
88 *
89 * The main advantage of this approach over the typical pattern using a literal
90 * load is that literal loads may miss in the D-cache, and generally lead to
91 * lower cache efficiency for variables that are referenced often from many
92 * different places in the code.
93 */
94static u32 get_group_rem(u32 group, u32 *offset)
95{
96 u32 val = *offset;
97 u32 shift;
98 do {
99 shift = val ? (31 - __fls(val)) & ~1 : 32;
100 *offset = val;
101 if (!val)
102 break;
103 val &= 0xffffff >> shift;
104 } while (group--);
105 return shift;
106}
107#endif
108
109int
110apply_relocate(Elf32_Shdr *sechdrs, const char *strtab, unsigned int symindex,
111 unsigned int relindex, struct module *module)
112{
113 Elf32_Shdr *symsec = sechdrs + symindex;
114 Elf32_Shdr *relsec = sechdrs + relindex;
115 Elf32_Shdr *dstsec = sechdrs + relsec->sh_info;
116 Elf32_Rel *rel = (void *)relsec->sh_addr;
117 unsigned int i;
118
119 for (i = 0; i < relsec->sh_size / sizeof(Elf32_Rel); i++, rel++) {
120 unsigned long loc;
121 Elf32_Sym *sym;
122 const char *symname;
123#ifdef CONFIG_ARM_HAS_GROUP_RELOCS
124 u32 shift, group = 1;
125#endif
126 s32 offset;
127 u32 tmp;
128#ifdef CONFIG_THUMB2_KERNEL
129 u32 upper, lower, sign, j1, j2;
130#endif
131
132 offset = ELF32_R_SYM(rel->r_info);
133 if (offset < 0 || offset > (symsec->sh_size / sizeof(Elf32_Sym))) {
134 pr_err("%s: section %u reloc %u: bad relocation sym offset\n",
135 module->name, relindex, i);
136 return -ENOEXEC;
137 }
138
139 sym = ((Elf32_Sym *)symsec->sh_addr) + offset;
140 symname = strtab + sym->st_name;
141
142 if (rel->r_offset < 0 || rel->r_offset > dstsec->sh_size - sizeof(u32)) {
143 pr_err("%s: section %u reloc %u sym '%s': out of bounds relocation, offset %d size %u\n",
144 module->name, relindex, i, symname,
145 rel->r_offset, dstsec->sh_size);
146 return -ENOEXEC;
147 }
148
149 loc = dstsec->sh_addr + rel->r_offset;
150
151 switch (ELF32_R_TYPE(rel->r_info)) {
152 case R_ARM_NONE:
153 /* ignore */
154 break;
155
156 case R_ARM_ABS32:
157 case R_ARM_TARGET1:
158 *(u32 *)loc += sym->st_value;
159 break;
160
161 case R_ARM_PC24:
162 case R_ARM_CALL:
163 case R_ARM_JUMP24:
164 if (sym->st_value & 3) {
165 pr_err("%s: section %u reloc %u sym '%s': unsupported interworking call (ARM -> Thumb)\n",
166 module->name, relindex, i, symname);
167 return -ENOEXEC;
168 }
169
170 offset = __mem_to_opcode_arm(*(u32 *)loc);
171 offset = (offset & 0x00ffffff) << 2;
172 offset = sign_extend32(offset, 25);
173
174 offset += sym->st_value - loc;
175
176 /*
177 * Route through a PLT entry if 'offset' exceeds the
178 * supported range. Note that 'offset + loc + 8'
179 * contains the absolute jump target, i.e.,
180 * @sym + addend, corrected for the +8 PC bias.
181 */
182 if (IS_ENABLED(CONFIG_ARM_MODULE_PLTS) &&
183 (offset <= (s32)0xfe000000 ||
184 offset >= (s32)0x02000000))
185 offset = get_module_plt(module, loc,
186 offset + loc + 8)
187 - loc - 8;
188
189 if (offset <= (s32)0xfe000000 ||
190 offset >= (s32)0x02000000) {
191 pr_err("%s: section %u reloc %u sym '%s': relocation %u out of range (%#lx -> %#x)\n",
192 module->name, relindex, i, symname,
193 ELF32_R_TYPE(rel->r_info), loc,
194 sym->st_value);
195 return -ENOEXEC;
196 }
197
198 offset >>= 2;
199 offset &= 0x00ffffff;
200
201 *(u32 *)loc &= __opcode_to_mem_arm(0xff000000);
202 *(u32 *)loc |= __opcode_to_mem_arm(offset);
203 break;
204
205 case R_ARM_V4BX:
206 /* Preserve Rm and the condition code. Alter
207 * other bits to re-code instruction as
208 * MOV PC,Rm.
209 */
210 *(u32 *)loc &= __opcode_to_mem_arm(0xf000000f);
211 *(u32 *)loc |= __opcode_to_mem_arm(0x01a0f000);
212 break;
213
214 case R_ARM_PREL31:
215 offset = (*(s32 *)loc << 1) >> 1; /* sign extend */
216 offset += sym->st_value - loc;
217 if (offset >= 0x40000000 || offset < -0x40000000) {
218 pr_err("%s: section %u reloc %u sym '%s': relocation %u out of range (%#lx -> %#x)\n",
219 module->name, relindex, i, symname,
220 ELF32_R_TYPE(rel->r_info), loc,
221 sym->st_value);
222 return -ENOEXEC;
223 }
224 *(u32 *)loc &= 0x80000000;
225 *(u32 *)loc |= offset & 0x7fffffff;
226 break;
227
228 case R_ARM_REL32:
229 *(u32 *)loc += sym->st_value - loc;
230 break;
231
232 case R_ARM_MOVW_ABS_NC:
233 case R_ARM_MOVT_ABS:
234 case R_ARM_MOVW_PREL_NC:
235 case R_ARM_MOVT_PREL:
236 offset = tmp = __mem_to_opcode_arm(*(u32 *)loc);
237 offset = ((offset & 0xf0000) >> 4) | (offset & 0xfff);
238 offset = sign_extend32(offset, 15);
239
240 offset += sym->st_value;
241 if (ELF32_R_TYPE(rel->r_info) == R_ARM_MOVT_PREL ||
242 ELF32_R_TYPE(rel->r_info) == R_ARM_MOVW_PREL_NC)
243 offset -= loc;
244 if (ELF32_R_TYPE(rel->r_info) == R_ARM_MOVT_ABS ||
245 ELF32_R_TYPE(rel->r_info) == R_ARM_MOVT_PREL)
246 offset >>= 16;
247
248 tmp &= 0xfff0f000;
249 tmp |= ((offset & 0xf000) << 4) |
250 (offset & 0x0fff);
251
252 *(u32 *)loc = __opcode_to_mem_arm(tmp);
253 break;
254
255#ifdef CONFIG_ARM_HAS_GROUP_RELOCS
256 case R_ARM_ALU_PC_G0_NC:
257 group = 0;
258 fallthrough;
259 case R_ARM_ALU_PC_G1_NC:
260 tmp = __mem_to_opcode_arm(*(u32 *)loc);
261 offset = ror32(tmp & 0xff, (tmp & 0xf00) >> 7);
262 if (tmp & BIT(22))
263 offset = -offset;
264 offset += sym->st_value - loc;
265 if (offset < 0) {
266 offset = -offset;
267 tmp = (tmp & ~BIT(23)) | BIT(22); // SUB opcode
268 } else {
269 tmp = (tmp & ~BIT(22)) | BIT(23); // ADD opcode
270 }
271
272 shift = get_group_rem(group, &offset);
273 if (shift < 24) {
274 offset >>= 24 - shift;
275 offset |= (shift + 8) << 7;
276 }
277 *(u32 *)loc = __opcode_to_mem_arm((tmp & ~0xfff) | offset);
278 break;
279
280 case R_ARM_LDR_PC_G2:
281 tmp = __mem_to_opcode_arm(*(u32 *)loc);
282 offset = tmp & 0xfff;
283 if (~tmp & BIT(23)) // U bit cleared?
284 offset = -offset;
285 offset += sym->st_value - loc;
286 if (offset < 0) {
287 offset = -offset;
288 tmp &= ~BIT(23); // clear U bit
289 } else {
290 tmp |= BIT(23); // set U bit
291 }
292 get_group_rem(2, &offset);
293
294 if (offset > 0xfff) {
295 pr_err("%s: section %u reloc %u sym '%s': relocation %u out of range (%#lx -> %#x)\n",
296 module->name, relindex, i, symname,
297 ELF32_R_TYPE(rel->r_info), loc,
298 sym->st_value);
299 return -ENOEXEC;
300 }
301 *(u32 *)loc = __opcode_to_mem_arm((tmp & ~0xfff) | offset);
302 break;
303#endif
304#ifdef CONFIG_THUMB2_KERNEL
305 case R_ARM_THM_CALL:
306 case R_ARM_THM_JUMP24:
307 /*
308 * For function symbols, only Thumb addresses are
309 * allowed (no interworking).
310 *
311 * For non-function symbols, the destination
312 * has no specific ARM/Thumb disposition, so
313 * the branch is resolved under the assumption
314 * that interworking is not required.
315 */
316 if (ELF32_ST_TYPE(sym->st_info) == STT_FUNC &&
317 !(sym->st_value & 1)) {
318 pr_err("%s: section %u reloc %u sym '%s': unsupported interworking call (Thumb -> ARM)\n",
319 module->name, relindex, i, symname);
320 return -ENOEXEC;
321 }
322
323 upper = __mem_to_opcode_thumb16(*(u16 *)loc);
324 lower = __mem_to_opcode_thumb16(*(u16 *)(loc + 2));
325
326 /*
327 * 25 bit signed address range (Thumb-2 BL and B.W
328 * instructions):
329 * S:I1:I2:imm10:imm11:0
330 * where:
331 * S = upper[10] = offset[24]
332 * I1 = ~(J1 ^ S) = offset[23]
333 * I2 = ~(J2 ^ S) = offset[22]
334 * imm10 = upper[9:0] = offset[21:12]
335 * imm11 = lower[10:0] = offset[11:1]
336 * J1 = lower[13]
337 * J2 = lower[11]
338 */
339 sign = (upper >> 10) & 1;
340 j1 = (lower >> 13) & 1;
341 j2 = (lower >> 11) & 1;
342 offset = (sign << 24) | ((~(j1 ^ sign) & 1) << 23) |
343 ((~(j2 ^ sign) & 1) << 22) |
344 ((upper & 0x03ff) << 12) |
345 ((lower & 0x07ff) << 1);
346 offset = sign_extend32(offset, 24);
347 offset += sym->st_value - loc;
348
349 /*
350 * Route through a PLT entry if 'offset' exceeds the
351 * supported range.
352 */
353 if (IS_ENABLED(CONFIG_ARM_MODULE_PLTS) &&
354 (offset <= (s32)0xff000000 ||
355 offset >= (s32)0x01000000))
356 offset = get_module_plt(module, loc,
357 offset + loc + 4)
358 - loc - 4;
359
360 if (offset <= (s32)0xff000000 ||
361 offset >= (s32)0x01000000) {
362 pr_err("%s: section %u reloc %u sym '%s': relocation %u out of range (%#lx -> %#x)\n",
363 module->name, relindex, i, symname,
364 ELF32_R_TYPE(rel->r_info), loc,
365 sym->st_value);
366 return -ENOEXEC;
367 }
368
369 sign = (offset >> 24) & 1;
370 j1 = sign ^ (~(offset >> 23) & 1);
371 j2 = sign ^ (~(offset >> 22) & 1);
372 upper = (u16)((upper & 0xf800) | (sign << 10) |
373 ((offset >> 12) & 0x03ff));
374 lower = (u16)((lower & 0xd000) |
375 (j1 << 13) | (j2 << 11) |
376 ((offset >> 1) & 0x07ff));
377
378 *(u16 *)loc = __opcode_to_mem_thumb16(upper);
379 *(u16 *)(loc + 2) = __opcode_to_mem_thumb16(lower);
380 break;
381
382 case R_ARM_THM_MOVW_ABS_NC:
383 case R_ARM_THM_MOVT_ABS:
384 case R_ARM_THM_MOVW_PREL_NC:
385 case R_ARM_THM_MOVT_PREL:
386 upper = __mem_to_opcode_thumb16(*(u16 *)loc);
387 lower = __mem_to_opcode_thumb16(*(u16 *)(loc + 2));
388
389 /*
390 * MOVT/MOVW instructions encoding in Thumb-2:
391 *
392 * i = upper[10]
393 * imm4 = upper[3:0]
394 * imm3 = lower[14:12]
395 * imm8 = lower[7:0]
396 *
397 * imm16 = imm4:i:imm3:imm8
398 */
399 offset = ((upper & 0x000f) << 12) |
400 ((upper & 0x0400) << 1) |
401 ((lower & 0x7000) >> 4) | (lower & 0x00ff);
402 offset = sign_extend32(offset, 15);
403 offset += sym->st_value;
404
405 if (ELF32_R_TYPE(rel->r_info) == R_ARM_THM_MOVT_PREL ||
406 ELF32_R_TYPE(rel->r_info) == R_ARM_THM_MOVW_PREL_NC)
407 offset -= loc;
408 if (ELF32_R_TYPE(rel->r_info) == R_ARM_THM_MOVT_ABS ||
409 ELF32_R_TYPE(rel->r_info) == R_ARM_THM_MOVT_PREL)
410 offset >>= 16;
411
412 upper = (u16)((upper & 0xfbf0) |
413 ((offset & 0xf000) >> 12) |
414 ((offset & 0x0800) >> 1));
415 lower = (u16)((lower & 0x8f00) |
416 ((offset & 0x0700) << 4) |
417 (offset & 0x00ff));
418 *(u16 *)loc = __opcode_to_mem_thumb16(upper);
419 *(u16 *)(loc + 2) = __opcode_to_mem_thumb16(lower);
420 break;
421#endif
422
423 default:
424 pr_err("%s: unknown relocation: %u\n",
425 module->name, ELF32_R_TYPE(rel->r_info));
426 return -ENOEXEC;
427 }
428 }
429 return 0;
430}
431
432struct mod_unwind_map {
433 const Elf_Shdr *unw_sec;
434 const Elf_Shdr *txt_sec;
435};
436
437static const Elf_Shdr *find_mod_section(const Elf32_Ehdr *hdr,
438 const Elf_Shdr *sechdrs, const char *name)
439{
440 const Elf_Shdr *s, *se;
441 const char *secstrs = (void *)hdr + sechdrs[hdr->e_shstrndx].sh_offset;
442
443 for (s = sechdrs, se = sechdrs + hdr->e_shnum; s < se; s++)
444 if (strcmp(name, secstrs + s->sh_name) == 0)
445 return s;
446
447 return NULL;
448}
449
450extern void fixup_pv_table(const void *, unsigned long);
451extern void fixup_smp(const void *, unsigned long);
452
453int module_finalize(const Elf32_Ehdr *hdr, const Elf_Shdr *sechdrs,
454 struct module *mod)
455{
456 const Elf_Shdr *s = NULL;
457#ifdef CONFIG_ARM_UNWIND
458 const char *secstrs = (void *)hdr + sechdrs[hdr->e_shstrndx].sh_offset;
459 const Elf_Shdr *sechdrs_end = sechdrs + hdr->e_shnum;
460 struct list_head *unwind_list = &mod->arch.unwind_list;
461
462 INIT_LIST_HEAD(unwind_list);
463 mod->arch.init_table = NULL;
464
465 for (s = sechdrs; s < sechdrs_end; s++) {
466 const char *secname = secstrs + s->sh_name;
467 const char *txtname;
468 const Elf_Shdr *txt_sec;
469
470 if (!(s->sh_flags & SHF_ALLOC) ||
471 s->sh_type != ELF_SECTION_UNWIND)
472 continue;
473
474 if (!strcmp(".ARM.exidx", secname))
475 txtname = ".text";
476 else
477 txtname = secname + strlen(".ARM.exidx");
478 txt_sec = find_mod_section(hdr, sechdrs, txtname);
479
480 if (txt_sec) {
481 struct unwind_table *table =
482 unwind_table_add(s->sh_addr,
483 s->sh_size,
484 txt_sec->sh_addr,
485 txt_sec->sh_size);
486
487 list_add(&table->mod_list, unwind_list);
488
489 /* save init table for module_arch_freeing_init */
490 if (strcmp(".ARM.exidx.init.text", secname) == 0)
491 mod->arch.init_table = table;
492 }
493 }
494#endif
495#ifdef CONFIG_ARM_PATCH_PHYS_VIRT
496 s = find_mod_section(hdr, sechdrs, ".pv_table");
497 if (s)
498 fixup_pv_table((void *)s->sh_addr, s->sh_size);
499#endif
500 s = find_mod_section(hdr, sechdrs, ".alt.smp.init");
501 if (s && !is_smp())
502#ifdef CONFIG_SMP_ON_UP
503 fixup_smp((void *)s->sh_addr, s->sh_size);
504#else
505 return -EINVAL;
506#endif
507 return 0;
508}
509
510void
511module_arch_cleanup(struct module *mod)
512{
513#ifdef CONFIG_ARM_UNWIND
514 struct unwind_table *tmp;
515 struct unwind_table *n;
516
517 list_for_each_entry_safe(tmp, n,
518 &mod->arch.unwind_list, mod_list) {
519 list_del(&tmp->mod_list);
520 unwind_table_del(tmp);
521 }
522 mod->arch.init_table = NULL;
523#endif
524}
525
526void __weak module_arch_freeing_init(struct module *mod)
527{
528#ifdef CONFIG_ARM_UNWIND
529 struct unwind_table *init = mod->arch.init_table;
530
531 if (init) {
532 mod->arch.init_table = NULL;
533 list_del(&init->mod_list);
534 unwind_table_del(init);
535 }
536#endif
537}
1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * linux/arch/arm/kernel/module.c
4 *
5 * Copyright (C) 2002 Russell King.
6 * Modified for nommu by Hyok S. Choi
7 *
8 * Module allocation method suggested by Andi Kleen.
9 */
10#include <linux/module.h>
11#include <linux/moduleloader.h>
12#include <linux/kernel.h>
13#include <linux/mm.h>
14#include <linux/elf.h>
15#include <linux/vmalloc.h>
16#include <linux/fs.h>
17#include <linux/string.h>
18#include <linux/gfp.h>
19
20#include <asm/pgtable.h>
21#include <asm/sections.h>
22#include <asm/smp_plat.h>
23#include <asm/unwind.h>
24#include <asm/opcodes.h>
25
26#ifdef CONFIG_XIP_KERNEL
27/*
28 * The XIP kernel text is mapped in the module area for modules and
29 * some other stuff to work without any indirect relocations.
30 * MODULES_VADDR is redefined here and not in asm/memory.h to avoid
31 * recompiling the whole kernel when CONFIG_XIP_KERNEL is turned on/off.
32 */
33#undef MODULES_VADDR
34#define MODULES_VADDR (((unsigned long)_exiprom + ~PMD_MASK) & PMD_MASK)
35#endif
36
37#ifdef CONFIG_MMU
38void *module_alloc(unsigned long size)
39{
40 gfp_t gfp_mask = GFP_KERNEL;
41 void *p;
42
43 /* Silence the initial allocation */
44 if (IS_ENABLED(CONFIG_ARM_MODULE_PLTS))
45 gfp_mask |= __GFP_NOWARN;
46
47 p = __vmalloc_node_range(size, 1, MODULES_VADDR, MODULES_END,
48 gfp_mask, PAGE_KERNEL_EXEC, 0, NUMA_NO_NODE,
49 __builtin_return_address(0));
50 if (!IS_ENABLED(CONFIG_ARM_MODULE_PLTS) || p)
51 return p;
52 return __vmalloc_node_range(size, 1, VMALLOC_START, VMALLOC_END,
53 GFP_KERNEL, PAGE_KERNEL_EXEC, 0, NUMA_NO_NODE,
54 __builtin_return_address(0));
55}
56#endif
57
58bool module_exit_section(const char *name)
59{
60 return strstarts(name, ".exit") ||
61 strstarts(name, ".ARM.extab.exit") ||
62 strstarts(name, ".ARM.exidx.exit");
63}
64
65int
66apply_relocate(Elf32_Shdr *sechdrs, const char *strtab, unsigned int symindex,
67 unsigned int relindex, struct module *module)
68{
69 Elf32_Shdr *symsec = sechdrs + symindex;
70 Elf32_Shdr *relsec = sechdrs + relindex;
71 Elf32_Shdr *dstsec = sechdrs + relsec->sh_info;
72 Elf32_Rel *rel = (void *)relsec->sh_addr;
73 unsigned int i;
74
75 for (i = 0; i < relsec->sh_size / sizeof(Elf32_Rel); i++, rel++) {
76 unsigned long loc;
77 Elf32_Sym *sym;
78 const char *symname;
79 s32 offset;
80 u32 tmp;
81#ifdef CONFIG_THUMB2_KERNEL
82 u32 upper, lower, sign, j1, j2;
83#endif
84
85 offset = ELF32_R_SYM(rel->r_info);
86 if (offset < 0 || offset > (symsec->sh_size / sizeof(Elf32_Sym))) {
87 pr_err("%s: section %u reloc %u: bad relocation sym offset\n",
88 module->name, relindex, i);
89 return -ENOEXEC;
90 }
91
92 sym = ((Elf32_Sym *)symsec->sh_addr) + offset;
93 symname = strtab + sym->st_name;
94
95 if (rel->r_offset < 0 || rel->r_offset > dstsec->sh_size - sizeof(u32)) {
96 pr_err("%s: section %u reloc %u sym '%s': out of bounds relocation, offset %d size %u\n",
97 module->name, relindex, i, symname,
98 rel->r_offset, dstsec->sh_size);
99 return -ENOEXEC;
100 }
101
102 loc = dstsec->sh_addr + rel->r_offset;
103
104 switch (ELF32_R_TYPE(rel->r_info)) {
105 case R_ARM_NONE:
106 /* ignore */
107 break;
108
109 case R_ARM_ABS32:
110 case R_ARM_TARGET1:
111 *(u32 *)loc += sym->st_value;
112 break;
113
114 case R_ARM_PC24:
115 case R_ARM_CALL:
116 case R_ARM_JUMP24:
117 if (sym->st_value & 3) {
118 pr_err("%s: section %u reloc %u sym '%s': unsupported interworking call (ARM -> Thumb)\n",
119 module->name, relindex, i, symname);
120 return -ENOEXEC;
121 }
122
123 offset = __mem_to_opcode_arm(*(u32 *)loc);
124 offset = (offset & 0x00ffffff) << 2;
125 if (offset & 0x02000000)
126 offset -= 0x04000000;
127
128 offset += sym->st_value - loc;
129
130 /*
131 * Route through a PLT entry if 'offset' exceeds the
132 * supported range. Note that 'offset + loc + 8'
133 * contains the absolute jump target, i.e.,
134 * @sym + addend, corrected for the +8 PC bias.
135 */
136 if (IS_ENABLED(CONFIG_ARM_MODULE_PLTS) &&
137 (offset <= (s32)0xfe000000 ||
138 offset >= (s32)0x02000000))
139 offset = get_module_plt(module, loc,
140 offset + loc + 8)
141 - loc - 8;
142
143 if (offset <= (s32)0xfe000000 ||
144 offset >= (s32)0x02000000) {
145 pr_err("%s: section %u reloc %u sym '%s': relocation %u out of range (%#lx -> %#x)\n",
146 module->name, relindex, i, symname,
147 ELF32_R_TYPE(rel->r_info), loc,
148 sym->st_value);
149 return -ENOEXEC;
150 }
151
152 offset >>= 2;
153 offset &= 0x00ffffff;
154
155 *(u32 *)loc &= __opcode_to_mem_arm(0xff000000);
156 *(u32 *)loc |= __opcode_to_mem_arm(offset);
157 break;
158
159 case R_ARM_V4BX:
160 /* Preserve Rm and the condition code. Alter
161 * other bits to re-code instruction as
162 * MOV PC,Rm.
163 */
164 *(u32 *)loc &= __opcode_to_mem_arm(0xf000000f);
165 *(u32 *)loc |= __opcode_to_mem_arm(0x01a0f000);
166 break;
167
168 case R_ARM_PREL31:
169 offset = (*(s32 *)loc << 1) >> 1; /* sign extend */
170 offset += sym->st_value - loc;
171 if (offset >= 0x40000000 || offset < -0x40000000) {
172 pr_err("%s: section %u reloc %u sym '%s': relocation %u out of range (%#lx -> %#x)\n",
173 module->name, relindex, i, symname,
174 ELF32_R_TYPE(rel->r_info), loc,
175 sym->st_value);
176 return -ENOEXEC;
177 }
178 *(u32 *)loc &= 0x80000000;
179 *(u32 *)loc |= offset & 0x7fffffff;
180 break;
181
182 case R_ARM_MOVW_ABS_NC:
183 case R_ARM_MOVT_ABS:
184 offset = tmp = __mem_to_opcode_arm(*(u32 *)loc);
185 offset = ((offset & 0xf0000) >> 4) | (offset & 0xfff);
186 offset = (offset ^ 0x8000) - 0x8000;
187
188 offset += sym->st_value;
189 if (ELF32_R_TYPE(rel->r_info) == R_ARM_MOVT_ABS)
190 offset >>= 16;
191
192 tmp &= 0xfff0f000;
193 tmp |= ((offset & 0xf000) << 4) |
194 (offset & 0x0fff);
195
196 *(u32 *)loc = __opcode_to_mem_arm(tmp);
197 break;
198
199#ifdef CONFIG_THUMB2_KERNEL
200 case R_ARM_THM_CALL:
201 case R_ARM_THM_JUMP24:
202 /*
203 * For function symbols, only Thumb addresses are
204 * allowed (no interworking).
205 *
206 * For non-function symbols, the destination
207 * has no specific ARM/Thumb disposition, so
208 * the branch is resolved under the assumption
209 * that interworking is not required.
210 */
211 if (ELF32_ST_TYPE(sym->st_info) == STT_FUNC &&
212 !(sym->st_value & 1)) {
213 pr_err("%s: section %u reloc %u sym '%s': unsupported interworking call (Thumb -> ARM)\n",
214 module->name, relindex, i, symname);
215 return -ENOEXEC;
216 }
217
218 upper = __mem_to_opcode_thumb16(*(u16 *)loc);
219 lower = __mem_to_opcode_thumb16(*(u16 *)(loc + 2));
220
221 /*
222 * 25 bit signed address range (Thumb-2 BL and B.W
223 * instructions):
224 * S:I1:I2:imm10:imm11:0
225 * where:
226 * S = upper[10] = offset[24]
227 * I1 = ~(J1 ^ S) = offset[23]
228 * I2 = ~(J2 ^ S) = offset[22]
229 * imm10 = upper[9:0] = offset[21:12]
230 * imm11 = lower[10:0] = offset[11:1]
231 * J1 = lower[13]
232 * J2 = lower[11]
233 */
234 sign = (upper >> 10) & 1;
235 j1 = (lower >> 13) & 1;
236 j2 = (lower >> 11) & 1;
237 offset = (sign << 24) | ((~(j1 ^ sign) & 1) << 23) |
238 ((~(j2 ^ sign) & 1) << 22) |
239 ((upper & 0x03ff) << 12) |
240 ((lower & 0x07ff) << 1);
241 if (offset & 0x01000000)
242 offset -= 0x02000000;
243 offset += sym->st_value - loc;
244
245 /*
246 * Route through a PLT entry if 'offset' exceeds the
247 * supported range.
248 */
249 if (IS_ENABLED(CONFIG_ARM_MODULE_PLTS) &&
250 (offset <= (s32)0xff000000 ||
251 offset >= (s32)0x01000000))
252 offset = get_module_plt(module, loc,
253 offset + loc + 4)
254 - loc - 4;
255
256 if (offset <= (s32)0xff000000 ||
257 offset >= (s32)0x01000000) {
258 pr_err("%s: section %u reloc %u sym '%s': relocation %u out of range (%#lx -> %#x)\n",
259 module->name, relindex, i, symname,
260 ELF32_R_TYPE(rel->r_info), loc,
261 sym->st_value);
262 return -ENOEXEC;
263 }
264
265 sign = (offset >> 24) & 1;
266 j1 = sign ^ (~(offset >> 23) & 1);
267 j2 = sign ^ (~(offset >> 22) & 1);
268 upper = (u16)((upper & 0xf800) | (sign << 10) |
269 ((offset >> 12) & 0x03ff));
270 lower = (u16)((lower & 0xd000) |
271 (j1 << 13) | (j2 << 11) |
272 ((offset >> 1) & 0x07ff));
273
274 *(u16 *)loc = __opcode_to_mem_thumb16(upper);
275 *(u16 *)(loc + 2) = __opcode_to_mem_thumb16(lower);
276 break;
277
278 case R_ARM_THM_MOVW_ABS_NC:
279 case R_ARM_THM_MOVT_ABS:
280 upper = __mem_to_opcode_thumb16(*(u16 *)loc);
281 lower = __mem_to_opcode_thumb16(*(u16 *)(loc + 2));
282
283 /*
284 * MOVT/MOVW instructions encoding in Thumb-2:
285 *
286 * i = upper[10]
287 * imm4 = upper[3:0]
288 * imm3 = lower[14:12]
289 * imm8 = lower[7:0]
290 *
291 * imm16 = imm4:i:imm3:imm8
292 */
293 offset = ((upper & 0x000f) << 12) |
294 ((upper & 0x0400) << 1) |
295 ((lower & 0x7000) >> 4) | (lower & 0x00ff);
296 offset = (offset ^ 0x8000) - 0x8000;
297 offset += sym->st_value;
298
299 if (ELF32_R_TYPE(rel->r_info) == R_ARM_THM_MOVT_ABS)
300 offset >>= 16;
301
302 upper = (u16)((upper & 0xfbf0) |
303 ((offset & 0xf000) >> 12) |
304 ((offset & 0x0800) >> 1));
305 lower = (u16)((lower & 0x8f00) |
306 ((offset & 0x0700) << 4) |
307 (offset & 0x00ff));
308 *(u16 *)loc = __opcode_to_mem_thumb16(upper);
309 *(u16 *)(loc + 2) = __opcode_to_mem_thumb16(lower);
310 break;
311#endif
312
313 default:
314 pr_err("%s: unknown relocation: %u\n",
315 module->name, ELF32_R_TYPE(rel->r_info));
316 return -ENOEXEC;
317 }
318 }
319 return 0;
320}
321
322struct mod_unwind_map {
323 const Elf_Shdr *unw_sec;
324 const Elf_Shdr *txt_sec;
325};
326
327static const Elf_Shdr *find_mod_section(const Elf32_Ehdr *hdr,
328 const Elf_Shdr *sechdrs, const char *name)
329{
330 const Elf_Shdr *s, *se;
331 const char *secstrs = (void *)hdr + sechdrs[hdr->e_shstrndx].sh_offset;
332
333 for (s = sechdrs, se = sechdrs + hdr->e_shnum; s < se; s++)
334 if (strcmp(name, secstrs + s->sh_name) == 0)
335 return s;
336
337 return NULL;
338}
339
340extern void fixup_pv_table(const void *, unsigned long);
341extern void fixup_smp(const void *, unsigned long);
342
343int module_finalize(const Elf32_Ehdr *hdr, const Elf_Shdr *sechdrs,
344 struct module *mod)
345{
346 const Elf_Shdr *s = NULL;
347#ifdef CONFIG_ARM_UNWIND
348 const char *secstrs = (void *)hdr + sechdrs[hdr->e_shstrndx].sh_offset;
349 const Elf_Shdr *sechdrs_end = sechdrs + hdr->e_shnum;
350 struct mod_unwind_map maps[ARM_SEC_MAX];
351 int i;
352
353 memset(maps, 0, sizeof(maps));
354
355 for (s = sechdrs; s < sechdrs_end; s++) {
356 const char *secname = secstrs + s->sh_name;
357
358 if (!(s->sh_flags & SHF_ALLOC))
359 continue;
360
361 if (strcmp(".ARM.exidx.init.text", secname) == 0)
362 maps[ARM_SEC_INIT].unw_sec = s;
363 else if (strcmp(".ARM.exidx", secname) == 0)
364 maps[ARM_SEC_CORE].unw_sec = s;
365 else if (strcmp(".ARM.exidx.exit.text", secname) == 0)
366 maps[ARM_SEC_EXIT].unw_sec = s;
367 else if (strcmp(".ARM.exidx.text.unlikely", secname) == 0)
368 maps[ARM_SEC_UNLIKELY].unw_sec = s;
369 else if (strcmp(".ARM.exidx.text.hot", secname) == 0)
370 maps[ARM_SEC_HOT].unw_sec = s;
371 else if (strcmp(".init.text", secname) == 0)
372 maps[ARM_SEC_INIT].txt_sec = s;
373 else if (strcmp(".text", secname) == 0)
374 maps[ARM_SEC_CORE].txt_sec = s;
375 else if (strcmp(".exit.text", secname) == 0)
376 maps[ARM_SEC_EXIT].txt_sec = s;
377 else if (strcmp(".text.unlikely", secname) == 0)
378 maps[ARM_SEC_UNLIKELY].txt_sec = s;
379 else if (strcmp(".text.hot", secname) == 0)
380 maps[ARM_SEC_HOT].txt_sec = s;
381 }
382
383 for (i = 0; i < ARM_SEC_MAX; i++)
384 if (maps[i].unw_sec && maps[i].txt_sec)
385 mod->arch.unwind[i] =
386 unwind_table_add(maps[i].unw_sec->sh_addr,
387 maps[i].unw_sec->sh_size,
388 maps[i].txt_sec->sh_addr,
389 maps[i].txt_sec->sh_size);
390#endif
391#ifdef CONFIG_ARM_PATCH_PHYS_VIRT
392 s = find_mod_section(hdr, sechdrs, ".pv_table");
393 if (s)
394 fixup_pv_table((void *)s->sh_addr, s->sh_size);
395#endif
396 s = find_mod_section(hdr, sechdrs, ".alt.smp.init");
397 if (s && !is_smp())
398#ifdef CONFIG_SMP_ON_UP
399 fixup_smp((void *)s->sh_addr, s->sh_size);
400#else
401 return -EINVAL;
402#endif
403 return 0;
404}
405
406void
407module_arch_cleanup(struct module *mod)
408{
409#ifdef CONFIG_ARM_UNWIND
410 int i;
411
412 for (i = 0; i < ARM_SEC_MAX; i++)
413 if (mod->arch.unwind[i])
414 unwind_table_del(mod->arch.unwind[i]);
415#endif
416}