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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)_etext + ~PMD_MASK) & PMD_MASK)
38#endif
39
40#ifdef CONFIG_MMU
41void *module_alloc(unsigned long size)
42{
43 return __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}
47#endif
48
49int
50apply_relocate(Elf32_Shdr *sechdrs, const char *strtab, unsigned int symindex,
51 unsigned int relindex, struct module *module)
52{
53 Elf32_Shdr *symsec = sechdrs + symindex;
54 Elf32_Shdr *relsec = sechdrs + relindex;
55 Elf32_Shdr *dstsec = sechdrs + relsec->sh_info;
56 Elf32_Rel *rel = (void *)relsec->sh_addr;
57 unsigned int i;
58
59 for (i = 0; i < relsec->sh_size / sizeof(Elf32_Rel); i++, rel++) {
60 unsigned long loc;
61 Elf32_Sym *sym;
62 const char *symname;
63 s32 offset;
64 u32 tmp;
65#ifdef CONFIG_THUMB2_KERNEL
66 u32 upper, lower, sign, j1, j2;
67#endif
68
69 offset = ELF32_R_SYM(rel->r_info);
70 if (offset < 0 || offset > (symsec->sh_size / sizeof(Elf32_Sym))) {
71 pr_err("%s: section %u reloc %u: bad relocation sym offset\n",
72 module->name, relindex, i);
73 return -ENOEXEC;
74 }
75
76 sym = ((Elf32_Sym *)symsec->sh_addr) + offset;
77 symname = strtab + sym->st_name;
78
79 if (rel->r_offset < 0 || rel->r_offset > dstsec->sh_size - sizeof(u32)) {
80 pr_err("%s: section %u reloc %u sym '%s': out of bounds relocation, offset %d size %u\n",
81 module->name, relindex, i, symname,
82 rel->r_offset, dstsec->sh_size);
83 return -ENOEXEC;
84 }
85
86 loc = dstsec->sh_addr + rel->r_offset;
87
88 switch (ELF32_R_TYPE(rel->r_info)) {
89 case R_ARM_NONE:
90
91 break;
92
93 case R_ARM_ABS32:
94 case R_ARM_TARGET1:
95 *(u32 *)loc += sym->st_value;
96 break;
97
98 case R_ARM_PC24:
99 case R_ARM_CALL:
100 case R_ARM_JUMP24:
101 if (sym->st_value & 3) {
102 pr_err("%s: section %u reloc %u sym '%s': unsupported interworking call (ARM -> Thumb)\n",
103 module->name, relindex, i, symname);
104 return -ENOEXEC;
105 }
106
107 offset = __mem_to_opcode_arm(*(u32 *)loc);
108 offset = (offset & 0x00ffffff) << 2;
109 if (offset & 0x02000000)
110 offset -= 0x04000000;
111
112 offset += sym->st_value - loc;
113 if (offset <= (s32)0xfe000000 ||
114 offset >= (s32)0x02000000) {
115 pr_err("%s: section %u reloc %u sym '%s': relocation %u out of range (%#lx -> %#x)\n",
116 module->name, relindex, i, symname,
117 ELF32_R_TYPE(rel->r_info), loc,
118 sym->st_value);
119 return -ENOEXEC;
120 }
121
122 offset >>= 2;
123 offset &= 0x00ffffff;
124
125 *(u32 *)loc &= __opcode_to_mem_arm(0xff000000);
126 *(u32 *)loc |= __opcode_to_mem_arm(offset);
127 break;
128
129 case R_ARM_V4BX:
130
131
132
133
134 *(u32 *)loc &= __opcode_to_mem_arm(0xf000000f);
135 *(u32 *)loc |= __opcode_to_mem_arm(0x01a0f000);
136 break;
137
138 case R_ARM_PREL31:
139 offset = *(u32 *)loc + sym->st_value - loc;
140 *(u32 *)loc = offset & 0x7fffffff;
141 break;
142
143 case R_ARM_MOVW_ABS_NC:
144 case R_ARM_MOVT_ABS:
145 offset = tmp = __mem_to_opcode_arm(*(u32 *)loc);
146 offset = ((offset & 0xf0000) >> 4) | (offset & 0xfff);
147 offset = (offset ^ 0x8000) - 0x8000;
148
149 offset += sym->st_value;
150 if (ELF32_R_TYPE(rel->r_info) == R_ARM_MOVT_ABS)
151 offset >>= 16;
152
153 tmp &= 0xfff0f000;
154 tmp |= ((offset & 0xf000) << 4) |
155 (offset & 0x0fff);
156
157 *(u32 *)loc = __opcode_to_mem_arm(tmp);
158 break;
159
160#ifdef CONFIG_THUMB2_KERNEL
161 case R_ARM_THM_CALL:
162 case R_ARM_THM_JUMP24:
163
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171
172 if (ELF32_ST_TYPE(sym->st_info) == STT_FUNC &&
173 !(sym->st_value & 1)) {
174 pr_err("%s: section %u reloc %u sym '%s': unsupported interworking call (Thumb -> ARM)\n",
175 module->name, relindex, i, symname);
176 return -ENOEXEC;
177 }
178
179 upper = __mem_to_opcode_thumb16(*(u16 *)loc);
180 lower = __mem_to_opcode_thumb16(*(u16 *)(loc + 2));
181
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194
195 sign = (upper >> 10) & 1;
196 j1 = (lower >> 13) & 1;
197 j2 = (lower >> 11) & 1;
198 offset = (sign << 24) | ((~(j1 ^ sign) & 1) << 23) |
199 ((~(j2 ^ sign) & 1) << 22) |
200 ((upper & 0x03ff) << 12) |
201 ((lower & 0x07ff) << 1);
202 if (offset & 0x01000000)
203 offset -= 0x02000000;
204 offset += sym->st_value - loc;
205
206 if (offset <= (s32)0xff000000 ||
207 offset >= (s32)0x01000000) {
208 pr_err("%s: section %u reloc %u sym '%s': relocation %u out of range (%#lx -> %#x)\n",
209 module->name, relindex, i, symname,
210 ELF32_R_TYPE(rel->r_info), loc,
211 sym->st_value);
212 return -ENOEXEC;
213 }
214
215 sign = (offset >> 24) & 1;
216 j1 = sign ^ (~(offset >> 23) & 1);
217 j2 = sign ^ (~(offset >> 22) & 1);
218 upper = (u16)((upper & 0xf800) | (sign << 10) |
219 ((offset >> 12) & 0x03ff));
220 lower = (u16)((lower & 0xd000) |
221 (j1 << 13) | (j2 << 11) |
222 ((offset >> 1) & 0x07ff));
223
224 *(u16 *)loc = __opcode_to_mem_thumb16(upper);
225 *(u16 *)(loc + 2) = __opcode_to_mem_thumb16(lower);
226 break;
227
228 case R_ARM_THM_MOVW_ABS_NC:
229 case R_ARM_THM_MOVT_ABS:
230 upper = __mem_to_opcode_thumb16(*(u16 *)loc);
231 lower = __mem_to_opcode_thumb16(*(u16 *)(loc + 2));
232
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242
243 offset = ((upper & 0x000f) << 12) |
244 ((upper & 0x0400) << 1) |
245 ((lower & 0x7000) >> 4) | (lower & 0x00ff);
246 offset = (offset ^ 0x8000) - 0x8000;
247 offset += sym->st_value;
248
249 if (ELF32_R_TYPE(rel->r_info) == R_ARM_THM_MOVT_ABS)
250 offset >>= 16;
251
252 upper = (u16)((upper & 0xfbf0) |
253 ((offset & 0xf000) >> 12) |
254 ((offset & 0x0800) >> 1));
255 lower = (u16)((lower & 0x8f00) |
256 ((offset & 0x0700) << 4) |
257 (offset & 0x00ff));
258 *(u16 *)loc = __opcode_to_mem_thumb16(upper);
259 *(u16 *)(loc + 2) = __opcode_to_mem_thumb16(lower);
260 break;
261#endif
262
263 default:
264 pr_err("%s: unknown relocation: %u\n",
265 module->name, ELF32_R_TYPE(rel->r_info));
266 return -ENOEXEC;
267 }
268 }
269 return 0;
270}
271
272struct mod_unwind_map {
273 const Elf_Shdr *unw_sec;
274 const Elf_Shdr *txt_sec;
275};
276
277static const Elf_Shdr *find_mod_section(const Elf32_Ehdr *hdr,
278 const Elf_Shdr *sechdrs, const char *name)
279{
280 const Elf_Shdr *s, *se;
281 const char *secstrs = (void *)hdr + sechdrs[hdr->e_shstrndx].sh_offset;
282
283 for (s = sechdrs, se = sechdrs + hdr->e_shnum; s < se; s++)
284 if (strcmp(name, secstrs + s->sh_name) == 0)
285 return s;
286
287 return NULL;
288}
289
290extern void fixup_pv_table(const void *, unsigned long);
291extern void fixup_smp(const void *, unsigned long);
292
293int module_finalize(const Elf32_Ehdr *hdr, const Elf_Shdr *sechdrs,
294 struct module *mod)
295{
296 const Elf_Shdr *s = NULL;
297#ifdef CONFIG_ARM_UNWIND
298 const char *secstrs = (void *)hdr + sechdrs[hdr->e_shstrndx].sh_offset;
299 const Elf_Shdr *sechdrs_end = sechdrs + hdr->e_shnum;
300 struct mod_unwind_map maps[ARM_SEC_MAX];
301 int i;
302
303 memset(maps, 0, sizeof(maps));
304
305 for (s = sechdrs; s < sechdrs_end; s++) {
306 const char *secname = secstrs + s->sh_name;
307
308 if (!(s->sh_flags & SHF_ALLOC))
309 continue;
310
311 if (strcmp(".ARM.exidx.init.text", secname) == 0)
312 maps[ARM_SEC_INIT].unw_sec = s;
313 else if (strcmp(".ARM.exidx", secname) == 0)
314 maps[ARM_SEC_CORE].unw_sec = s;
315 else if (strcmp(".ARM.exidx.exit.text", secname) == 0)
316 maps[ARM_SEC_EXIT].unw_sec = s;
317 else if (strcmp(".ARM.exidx.text.unlikely", secname) == 0)
318 maps[ARM_SEC_UNLIKELY].unw_sec = s;
319 else if (strcmp(".ARM.exidx.text.hot", secname) == 0)
320 maps[ARM_SEC_HOT].unw_sec = s;
321 else if (strcmp(".init.text", secname) == 0)
322 maps[ARM_SEC_INIT].txt_sec = s;
323 else if (strcmp(".text", secname) == 0)
324 maps[ARM_SEC_CORE].txt_sec = s;
325 else if (strcmp(".exit.text", secname) == 0)
326 maps[ARM_SEC_EXIT].txt_sec = s;
327 else if (strcmp(".text.unlikely", secname) == 0)
328 maps[ARM_SEC_UNLIKELY].txt_sec = s;
329 else if (strcmp(".text.hot", secname) == 0)
330 maps[ARM_SEC_HOT].txt_sec = s;
331 }
332
333 for (i = 0; i < ARM_SEC_MAX; i++)
334 if (maps[i].unw_sec && maps[i].txt_sec)
335 mod->arch.unwind[i] =
336 unwind_table_add(maps[i].unw_sec->sh_addr,
337 maps[i].unw_sec->sh_size,
338 maps[i].txt_sec->sh_addr,
339 maps[i].txt_sec->sh_size);
340#endif
341#ifdef CONFIG_ARM_PATCH_PHYS_VIRT
342 s = find_mod_section(hdr, sechdrs, ".pv_table");
343 if (s)
344 fixup_pv_table((void *)s->sh_addr, s->sh_size);
345#endif
346 s = find_mod_section(hdr, sechdrs, ".alt.smp.init");
347 if (s && !is_smp())
348#ifdef CONFIG_SMP_ON_UP
349 fixup_smp((void *)s->sh_addr, s->sh_size);
350#else
351 return -EINVAL;
352#endif
353 return 0;
354}
355
356void
357module_arch_cleanup(struct module *mod)
358{
359#ifdef CONFIG_ARM_UNWIND
360 int i;
361
362 for (i = 0; i < ARM_SEC_MAX; i++)
363 if (mod->arch.unwind[i])
364 unwind_table_del(mod->arch.unwind[i]);
365#endif
366}
367
