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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
29
30
31
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
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
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
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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
161
162
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;
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:
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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
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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
247
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));
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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}
417
