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