1
2
3
4
5
6
7
8
9
10
11
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
32
33
34
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 gfp_t gfp_mask = GFP_KERNEL;
44 void *p;
45
46
47 if (IS_ENABLED(CONFIG_ARM_MODULE_PLTS))
48 gfp_mask |= __GFP_NOWARN;
49
50 p = __vmalloc_node_range(size, 1, MODULES_VADDR, MODULES_END,
51 gfp_mask, PAGE_KERNEL_EXEC, 0, NUMA_NO_NODE,
52 __builtin_return_address(0));
53 if (!IS_ENABLED(CONFIG_ARM_MODULE_PLTS) || p)
54 return p;
55 return __vmalloc_node_range(size, 1, VMALLOC_START, VMALLOC_END,
56 GFP_KERNEL, PAGE_KERNEL_EXEC, 0, NUMA_NO_NODE,
57 __builtin_return_address(0));
58}
59#endif
60
61int
62apply_relocate(Elf32_Shdr *sechdrs, const char *strtab, unsigned int symindex,
63 unsigned int relindex, struct module *module)
64{
65 Elf32_Shdr *symsec = sechdrs + symindex;
66 Elf32_Shdr *relsec = sechdrs + relindex;
67 Elf32_Shdr *dstsec = sechdrs + relsec->sh_info;
68 Elf32_Rel *rel = (void *)relsec->sh_addr;
69 unsigned int i;
70
71 for (i = 0; i < relsec->sh_size / sizeof(Elf32_Rel); i++, rel++) {
72 unsigned long loc;
73 Elf32_Sym *sym;
74 const char *symname;
75 s32 offset;
76 u32 tmp;
77#ifdef CONFIG_THUMB2_KERNEL
78 u32 upper, lower, sign, j1, j2;
79#endif
80
81 offset = ELF32_R_SYM(rel->r_info);
82 if (offset < 0 || offset > (symsec->sh_size / sizeof(Elf32_Sym))) {
83 pr_err("%s: section %u reloc %u: bad relocation sym offset\n",
84 module->name, relindex, i);
85 return -ENOEXEC;
86 }
87
88 sym = ((Elf32_Sym *)symsec->sh_addr) + offset;
89 symname = strtab + sym->st_name;
90
91 if (rel->r_offset < 0 || rel->r_offset > dstsec->sh_size - sizeof(u32)) {
92 pr_err("%s: section %u reloc %u sym '%s': out of bounds relocation, offset %d size %u\n",
93 module->name, relindex, i, symname,
94 rel->r_offset, dstsec->sh_size);
95 return -ENOEXEC;
96 }
97
98 loc = dstsec->sh_addr + rel->r_offset;
99
100 switch (ELF32_R_TYPE(rel->r_info)) {
101 case R_ARM_NONE:
102
103 break;
104
105 case R_ARM_ABS32:
106 case R_ARM_TARGET1:
107 *(u32 *)loc += sym->st_value;
108 break;
109
110 case R_ARM_PC24:
111 case R_ARM_CALL:
112 case R_ARM_JUMP24:
113 if (sym->st_value & 3) {
114 pr_err("%s: section %u reloc %u sym '%s': unsupported interworking call (ARM -> Thumb)\n",
115 module->name, relindex, i, symname);
116 return -ENOEXEC;
117 }
118
119 offset = __mem_to_opcode_arm(*(u32 *)loc);
120 offset = (offset & 0x00ffffff) << 2;
121 if (offset & 0x02000000)
122 offset -= 0x04000000;
123
124 offset += sym->st_value - loc;
125
126
127
128
129
130
131
132 if (IS_ENABLED(CONFIG_ARM_MODULE_PLTS) &&
133 (offset <= (s32)0xfe000000 ||
134 offset >= (s32)0x02000000))
135 offset = get_module_plt(module, loc,
136 offset + loc + 8)
137 - loc - 8;
138
139 if (offset <= (s32)0xfe000000 ||
140 offset >= (s32)0x02000000) {
141 pr_err("%s: section %u reloc %u sym '%s': relocation %u out of range (%#lx -> %#x)\n",
142 module->name, relindex, i, symname,
143 ELF32_R_TYPE(rel->r_info), loc,
144 sym->st_value);
145 return -ENOEXEC;
146 }
147
148 offset >>= 2;
149 offset &= 0x00ffffff;
150
151 *(u32 *)loc &= __opcode_to_mem_arm(0xff000000);
152 *(u32 *)loc |= __opcode_to_mem_arm(offset);
153 break;
154
155 case R_ARM_V4BX:
156
157
158
159
160 *(u32 *)loc &= __opcode_to_mem_arm(0xf000000f);
161 *(u32 *)loc |= __opcode_to_mem_arm(0x01a0f000);
162 break;
163
164 case R_ARM_PREL31:
165 offset = (*(s32 *)loc << 1) >> 1;
166 offset += sym->st_value - loc;
167 if (offset >= 0x40000000 || offset < -0x40000000) {
168 pr_err("%s: section %u reloc %u sym '%s': relocation %u out of range (%#lx -> %#x)\n",
169 module->name, relindex, i, symname,
170 ELF32_R_TYPE(rel->r_info), loc,
171 sym->st_value);
172 return -ENOEXEC;
173 }
174 *(u32 *)loc &= 0x80000000;
175 *(u32 *)loc |= offset & 0x7fffffff;
176 break;
177
178 case R_ARM_MOVW_ABS_NC:
179 case R_ARM_MOVT_ABS:
180 offset = tmp = __mem_to_opcode_arm(*(u32 *)loc);
181 offset = ((offset & 0xf0000) >> 4) | (offset & 0xfff);
182 offset = (offset ^ 0x8000) - 0x8000;
183
184 offset += sym->st_value;
185 if (ELF32_R_TYPE(rel->r_info) == R_ARM_MOVT_ABS)
186 offset >>= 16;
187
188 tmp &= 0xfff0f000;
189 tmp |= ((offset & 0xf000) << 4) |
190 (offset & 0x0fff);
191
192 *(u32 *)loc = __opcode_to_mem_arm(tmp);
193 break;
194
195#ifdef CONFIG_THUMB2_KERNEL
196 case R_ARM_THM_CALL:
197 case R_ARM_THM_JUMP24:
198
199
200
201
202
203
204
205
206
207 if (ELF32_ST_TYPE(sym->st_info) == STT_FUNC &&
208 !(sym->st_value & 1)) {
209 pr_err("%s: section %u reloc %u sym '%s': unsupported interworking call (Thumb -> ARM)\n",
210 module->name, relindex, i, symname);
211 return -ENOEXEC;
212 }
213
214 upper = __mem_to_opcode_thumb16(*(u16 *)loc);
215 lower = __mem_to_opcode_thumb16(*(u16 *)(loc + 2));
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230 sign = (upper >> 10) & 1;
231 j1 = (lower >> 13) & 1;
232 j2 = (lower >> 11) & 1;
233 offset = (sign << 24) | ((~(j1 ^ sign) & 1) << 23) |
234 ((~(j2 ^ sign) & 1) << 22) |
235 ((upper & 0x03ff) << 12) |
236 ((lower & 0x07ff) << 1);
237 if (offset & 0x01000000)
238 offset -= 0x02000000;
239 offset += sym->st_value - loc;
240
241
242
243
244
245 if (IS_ENABLED(CONFIG_ARM_MODULE_PLTS) &&
246 (offset <= (s32)0xff000000 ||
247 offset >= (s32)0x01000000))
248 offset = get_module_plt(module, loc,
249 offset + loc + 4)
250 - loc - 4;
251
252 if (offset <= (s32)0xff000000 ||
253 offset >= (s32)0x01000000) {
254 pr_err("%s: section %u reloc %u sym '%s': relocation %u out of range (%#lx -> %#x)\n",
255 module->name, relindex, i, symname,
256 ELF32_R_TYPE(rel->r_info), loc,
257 sym->st_value);
258 return -ENOEXEC;
259 }
260
261 sign = (offset >> 24) & 1;
262 j1 = sign ^ (~(offset >> 23) & 1);
263 j2 = sign ^ (~(offset >> 22) & 1);
264 upper = (u16)((upper & 0xf800) | (sign << 10) |
265 ((offset >> 12) & 0x03ff));
266 lower = (u16)((lower & 0xd000) |
267 (j1 << 13) | (j2 << 11) |
268 ((offset >> 1) & 0x07ff));
269
270 *(u16 *)loc = __opcode_to_mem_thumb16(upper);
271 *(u16 *)(loc + 2) = __opcode_to_mem_thumb16(lower);
272 break;
273
274 case R_ARM_THM_MOVW_ABS_NC:
275 case R_ARM_THM_MOVT_ABS:
276 upper = __mem_to_opcode_thumb16(*(u16 *)loc);
277 lower = __mem_to_opcode_thumb16(*(u16 *)(loc + 2));
278
279
280
281
282
283
284
285
286
287
288
289 offset = ((upper & 0x000f) << 12) |
290 ((upper & 0x0400) << 1) |
291 ((lower & 0x7000) >> 4) | (lower & 0x00ff);
292 offset = (offset ^ 0x8000) - 0x8000;
293 offset += sym->st_value;
294
295 if (ELF32_R_TYPE(rel->r_info) == R_ARM_THM_MOVT_ABS)
296 offset >>= 16;
297
298 upper = (u16)((upper & 0xfbf0) |
299 ((offset & 0xf000) >> 12) |
300 ((offset & 0x0800) >> 1));
301 lower = (u16)((lower & 0x8f00) |
302 ((offset & 0x0700) << 4) |
303 (offset & 0x00ff));
304 *(u16 *)loc = __opcode_to_mem_thumb16(upper);
305 *(u16 *)(loc + 2) = __opcode_to_mem_thumb16(lower);
306 break;
307#endif
308
309 default:
310 pr_err("%s: unknown relocation: %u\n",
311 module->name, ELF32_R_TYPE(rel->r_info));
312 return -ENOEXEC;
313 }
314 }
315 return 0;
316}
317
318struct mod_unwind_map {
319 const Elf_Shdr *unw_sec;
320 const Elf_Shdr *txt_sec;
321};
322
323static const Elf_Shdr *find_mod_section(const Elf32_Ehdr *hdr,
324 const Elf_Shdr *sechdrs, const char *name)
325{
326 const Elf_Shdr *s, *se;
327 const char *secstrs = (void *)hdr + sechdrs[hdr->e_shstrndx].sh_offset;
328
329 for (s = sechdrs, se = sechdrs + hdr->e_shnum; s < se; s++)
330 if (strcmp(name, secstrs + s->sh_name) == 0)
331 return s;
332
333 return NULL;
334}
335
336extern void fixup_pv_table(const void *, unsigned long);
337extern void fixup_smp(const void *, unsigned long);
338
339int module_finalize(const Elf32_Ehdr *hdr, const Elf_Shdr *sechdrs,
340 struct module *mod)
341{
342 const Elf_Shdr *s = NULL;
343#ifdef CONFIG_ARM_UNWIND
344 const char *secstrs = (void *)hdr + sechdrs[hdr->e_shstrndx].sh_offset;
345 const Elf_Shdr *sechdrs_end = sechdrs + hdr->e_shnum;
346 struct mod_unwind_map maps[ARM_SEC_MAX];
347 int i;
348
349 memset(maps, 0, sizeof(maps));
350
351 for (s = sechdrs; s < sechdrs_end; s++) {
352 const char *secname = secstrs + s->sh_name;
353
354 if (!(s->sh_flags & SHF_ALLOC))
355 continue;
356
357 if (strcmp(".ARM.exidx.init.text", secname) == 0)
358 maps[ARM_SEC_INIT].unw_sec = s;
359 else if (strcmp(".ARM.exidx", secname) == 0)
360 maps[ARM_SEC_CORE].unw_sec = s;
361 else if (strcmp(".ARM.exidx.exit.text", secname) == 0)
362 maps[ARM_SEC_EXIT].unw_sec = s;
363 else if (strcmp(".ARM.exidx.text.unlikely", secname) == 0)
364 maps[ARM_SEC_UNLIKELY].unw_sec = s;
365 else if (strcmp(".ARM.exidx.text.hot", secname) == 0)
366 maps[ARM_SEC_HOT].unw_sec = s;
367 else if (strcmp(".init.text", secname) == 0)
368 maps[ARM_SEC_INIT].txt_sec = s;
369 else if (strcmp(".text", secname) == 0)
370 maps[ARM_SEC_CORE].txt_sec = s;
371 else if (strcmp(".exit.text", secname) == 0)
372 maps[ARM_SEC_EXIT].txt_sec = s;
373 else if (strcmp(".text.unlikely", secname) == 0)
374 maps[ARM_SEC_UNLIKELY].txt_sec = s;
375 else if (strcmp(".text.hot", secname) == 0)
376 maps[ARM_SEC_HOT].txt_sec = s;
377 }
378
379 for (i = 0; i < ARM_SEC_MAX; i++)
380 if (maps[i].unw_sec && maps[i].txt_sec)
381 mod->arch.unwind[i] =
382 unwind_table_add(maps[i].unw_sec->sh_addr,
383 maps[i].unw_sec->sh_size,
384 maps[i].txt_sec->sh_addr,
385 maps[i].txt_sec->sh_size);
386#endif
387#ifdef CONFIG_ARM_PATCH_PHYS_VIRT
388 s = find_mod_section(hdr, sechdrs, ".pv_table");
389 if (s)
390 fixup_pv_table((void *)s->sh_addr, s->sh_size);
391#endif
392 s = find_mod_section(hdr, sechdrs, ".alt.smp.init");
393 if (s && !is_smp())
394#ifdef CONFIG_SMP_ON_UP
395 fixup_smp((void *)s->sh_addr, s->sh_size);
396#else
397 return -EINVAL;
398#endif
399 return 0;
400}
401
402void
403module_arch_cleanup(struct module *mod)
404{
405#ifdef CONFIG_ARM_UNWIND
406 int i;
407
408 for (i = 0; i < ARM_SEC_MAX; i++)
409 if (mod->arch.unwind[i])
410 unwind_table_del(mod->arch.unwind[i]);
411#endif
412}
413
