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1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 *
4 * Copyright (C) 2001 Rusty Russell.
5 * Copyright (C) 2003, 2004 Ralf Baechle (ralf@linux-mips.org)
6 * Copyright (C) 2005 Thiemo Seufer
7 */
8
9#undef DEBUG
10
11#include <linux/extable.h>
12#include <linux/moduleloader.h>
13#include <linux/elf.h>
14#include <linux/mm.h>
15#include <linux/numa.h>
16#include <linux/vmalloc.h>
17#include <linux/slab.h>
18#include <linux/fs.h>
19#include <linux/string.h>
20#include <linux/kernel.h>
21#include <linux/spinlock.h>
22#include <linux/jump_label.h>
23
24#include <asm/pgtable.h> /* MODULE_START */
25
26struct mips_hi16 {
27 struct mips_hi16 *next;
28 Elf_Addr *addr;
29 Elf_Addr value;
30};
31
32static LIST_HEAD(dbe_list);
33static DEFINE_SPINLOCK(dbe_lock);
34
35#ifdef MODULE_START
36void *module_alloc(unsigned long size)
37{
38 return __vmalloc_node_range(size, 1, MODULE_START, MODULE_END,
39 GFP_KERNEL, PAGE_KERNEL, 0, NUMA_NO_NODE,
40 __builtin_return_address(0));
41}
42#endif
43
44static int apply_r_mips_none(struct module *me, u32 *location,
45 u32 base, Elf_Addr v, bool rela)
46{
47 return 0;
48}
49
50static int apply_r_mips_32(struct module *me, u32 *location,
51 u32 base, Elf_Addr v, bool rela)
52{
53 *location = base + v;
54
55 return 0;
56}
57
58static int apply_r_mips_26(struct module *me, u32 *location,
59 u32 base, Elf_Addr v, bool rela)
60{
61 if (v % 4) {
62 pr_err("module %s: dangerous R_MIPS_26 relocation\n",
63 me->name);
64 return -ENOEXEC;
65 }
66
67 if ((v & 0xf0000000) != (((unsigned long)location + 4) & 0xf0000000)) {
68 pr_err("module %s: relocation overflow\n",
69 me->name);
70 return -ENOEXEC;
71 }
72
73 *location = (*location & ~0x03ffffff) |
74 ((base + (v >> 2)) & 0x03ffffff);
75
76 return 0;
77}
78
79static int apply_r_mips_hi16(struct module *me, u32 *location,
80 u32 base, Elf_Addr v, bool rela)
81{
82 struct mips_hi16 *n;
83
84 if (rela) {
85 *location = (*location & 0xffff0000) |
86 ((((long long) v + 0x8000LL) >> 16) & 0xffff);
87 return 0;
88 }
89
90 /*
91 * We cannot relocate this one now because we don't know the value of
92 * the carry we need to add. Save the information, and let LO16 do the
93 * actual relocation.
94 */
95 n = kmalloc(sizeof *n, GFP_KERNEL);
96 if (!n)
97 return -ENOMEM;
98
99 n->addr = (Elf_Addr *)location;
100 n->value = v;
101 n->next = me->arch.r_mips_hi16_list;
102 me->arch.r_mips_hi16_list = n;
103
104 return 0;
105}
106
107static void free_relocation_chain(struct mips_hi16 *l)
108{
109 struct mips_hi16 *next;
110
111 while (l) {
112 next = l->next;
113 kfree(l);
114 l = next;
115 }
116}
117
118static int apply_r_mips_lo16(struct module *me, u32 *location,
119 u32 base, Elf_Addr v, bool rela)
120{
121 unsigned long insnlo = base;
122 struct mips_hi16 *l;
123 Elf_Addr val, vallo;
124
125 if (rela) {
126 *location = (*location & 0xffff0000) | (v & 0xffff);
127 return 0;
128 }
129
130 /* Sign extend the addend we extract from the lo insn. */
131 vallo = ((insnlo & 0xffff) ^ 0x8000) - 0x8000;
132
133 if (me->arch.r_mips_hi16_list != NULL) {
134 l = me->arch.r_mips_hi16_list;
135 while (l != NULL) {
136 struct mips_hi16 *next;
137 unsigned long insn;
138
139 /*
140 * The value for the HI16 had best be the same.
141 */
142 if (v != l->value)
143 goto out_danger;
144
145 /*
146 * Do the HI16 relocation. Note that we actually don't
147 * need to know anything about the LO16 itself, except
148 * where to find the low 16 bits of the addend needed
149 * by the LO16.
150 */
151 insn = *l->addr;
152 val = ((insn & 0xffff) << 16) + vallo;
153 val += v;
154
155 /*
156 * Account for the sign extension that will happen in
157 * the low bits.
158 */
159 val = ((val >> 16) + ((val & 0x8000) != 0)) & 0xffff;
160
161 insn = (insn & ~0xffff) | val;
162 *l->addr = insn;
163
164 next = l->next;
165 kfree(l);
166 l = next;
167 }
168
169 me->arch.r_mips_hi16_list = NULL;
170 }
171
172 /*
173 * Ok, we're done with the HI16 relocs. Now deal with the LO16.
174 */
175 val = v + vallo;
176 insnlo = (insnlo & ~0xffff) | (val & 0xffff);
177 *location = insnlo;
178
179 return 0;
180
181out_danger:
182 free_relocation_chain(l);
183 me->arch.r_mips_hi16_list = NULL;
184
185 pr_err("module %s: dangerous R_MIPS_LO16 relocation\n", me->name);
186
187 return -ENOEXEC;
188}
189
190static int apply_r_mips_pc(struct module *me, u32 *location, u32 base,
191 Elf_Addr v, unsigned int bits)
192{
193 unsigned long mask = GENMASK(bits - 1, 0);
194 unsigned long se_bits;
195 long offset;
196
197 if (v % 4) {
198 pr_err("module %s: dangerous R_MIPS_PC%u relocation\n",
199 me->name, bits);
200 return -ENOEXEC;
201 }
202
203 /* retrieve & sign extend implicit addend if any */
204 offset = base & mask;
205 offset |= (offset & BIT(bits - 1)) ? ~mask : 0;
206
207 offset += ((long)v - (long)location) >> 2;
208
209 /* check the sign bit onwards are identical - ie. we didn't overflow */
210 se_bits = (offset & BIT(bits - 1)) ? ~0ul : 0;
211 if ((offset & ~mask) != (se_bits & ~mask)) {
212 pr_err("module %s: relocation overflow\n", me->name);
213 return -ENOEXEC;
214 }
215
216 *location = (*location & ~mask) | (offset & mask);
217
218 return 0;
219}
220
221static int apply_r_mips_pc16(struct module *me, u32 *location,
222 u32 base, Elf_Addr v, bool rela)
223{
224 return apply_r_mips_pc(me, location, base, v, 16);
225}
226
227static int apply_r_mips_pc21(struct module *me, u32 *location,
228 u32 base, Elf_Addr v, bool rela)
229{
230 return apply_r_mips_pc(me, location, base, v, 21);
231}
232
233static int apply_r_mips_pc26(struct module *me, u32 *location,
234 u32 base, Elf_Addr v, bool rela)
235{
236 return apply_r_mips_pc(me, location, base, v, 26);
237}
238
239static int apply_r_mips_64(struct module *me, u32 *location,
240 u32 base, Elf_Addr v, bool rela)
241{
242 if (WARN_ON(!rela))
243 return -EINVAL;
244
245 *(Elf_Addr *)location = v;
246
247 return 0;
248}
249
250static int apply_r_mips_higher(struct module *me, u32 *location,
251 u32 base, Elf_Addr v, bool rela)
252{
253 if (WARN_ON(!rela))
254 return -EINVAL;
255
256 *location = (*location & 0xffff0000) |
257 ((((long long)v + 0x80008000LL) >> 32) & 0xffff);
258
259 return 0;
260}
261
262static int apply_r_mips_highest(struct module *me, u32 *location,
263 u32 base, Elf_Addr v, bool rela)
264{
265 if (WARN_ON(!rela))
266 return -EINVAL;
267
268 *location = (*location & 0xffff0000) |
269 ((((long long)v + 0x800080008000LL) >> 48) & 0xffff);
270
271 return 0;
272}
273
274/**
275 * reloc_handler() - Apply a particular relocation to a module
276 * @me: the module to apply the reloc to
277 * @location: the address at which the reloc is to be applied
278 * @base: the existing value at location for REL-style; 0 for RELA-style
279 * @v: the value of the reloc, with addend for RELA-style
280 *
281 * Each implemented reloc_handler function applies a particular type of
282 * relocation to the module @me. Relocs that may be found in either REL or RELA
283 * variants can be handled by making use of the @base & @v parameters which are
284 * set to values which abstract the difference away from the particular reloc
285 * implementations.
286 *
287 * Return: 0 upon success, else -ERRNO
288 */
289typedef int (*reloc_handler)(struct module *me, u32 *location,
290 u32 base, Elf_Addr v, bool rela);
291
292/* The handlers for known reloc types */
293static reloc_handler reloc_handlers[] = {
294 [R_MIPS_NONE] = apply_r_mips_none,
295 [R_MIPS_32] = apply_r_mips_32,
296 [R_MIPS_26] = apply_r_mips_26,
297 [R_MIPS_HI16] = apply_r_mips_hi16,
298 [R_MIPS_LO16] = apply_r_mips_lo16,
299 [R_MIPS_PC16] = apply_r_mips_pc16,
300 [R_MIPS_64] = apply_r_mips_64,
301 [R_MIPS_HIGHER] = apply_r_mips_higher,
302 [R_MIPS_HIGHEST] = apply_r_mips_highest,
303 [R_MIPS_PC21_S2] = apply_r_mips_pc21,
304 [R_MIPS_PC26_S2] = apply_r_mips_pc26,
305};
306
307static int __apply_relocate(Elf_Shdr *sechdrs, const char *strtab,
308 unsigned int symindex, unsigned int relsec,
309 struct module *me, bool rela)
310{
311 union {
312 Elf_Mips_Rel *rel;
313 Elf_Mips_Rela *rela;
314 } r;
315 reloc_handler handler;
316 Elf_Sym *sym;
317 u32 *location, base;
318 unsigned int i, type;
319 Elf_Addr v;
320 int err = 0;
321 size_t reloc_sz;
322
323 pr_debug("Applying relocate section %u to %u\n", relsec,
324 sechdrs[relsec].sh_info);
325
326 r.rel = (void *)sechdrs[relsec].sh_addr;
327 reloc_sz = rela ? sizeof(*r.rela) : sizeof(*r.rel);
328 me->arch.r_mips_hi16_list = NULL;
329 for (i = 0; i < sechdrs[relsec].sh_size / reloc_sz; i++) {
330 /* This is where to make the change */
331 location = (void *)sechdrs[sechdrs[relsec].sh_info].sh_addr
332 + r.rel->r_offset;
333 /* This is the symbol it is referring to */
334 sym = (Elf_Sym *)sechdrs[symindex].sh_addr
335 + ELF_MIPS_R_SYM(*r.rel);
336 if (sym->st_value >= -MAX_ERRNO) {
337 /* Ignore unresolved weak symbol */
338 if (ELF_ST_BIND(sym->st_info) == STB_WEAK)
339 continue;
340 pr_warn("%s: Unknown symbol %s\n",
341 me->name, strtab + sym->st_name);
342 err = -ENOENT;
343 goto out;
344 }
345
346 type = ELF_MIPS_R_TYPE(*r.rel);
347 if (type < ARRAY_SIZE(reloc_handlers))
348 handler = reloc_handlers[type];
349 else
350 handler = NULL;
351
352 if (!handler) {
353 pr_err("%s: Unknown relocation type %u\n",
354 me->name, type);
355 err = -EINVAL;
356 goto out;
357 }
358
359 if (rela) {
360 v = sym->st_value + r.rela->r_addend;
361 base = 0;
362 r.rela = &r.rela[1];
363 } else {
364 v = sym->st_value;
365 base = *location;
366 r.rel = &r.rel[1];
367 }
368
369 err = handler(me, location, base, v, rela);
370 if (err)
371 goto out;
372 }
373
374out:
375 /*
376 * Normally the hi16 list should be deallocated at this point. A
377 * malformed binary however could contain a series of R_MIPS_HI16
378 * relocations not followed by a R_MIPS_LO16 relocation, or if we hit
379 * an error processing a reloc we might have gotten here before
380 * reaching the R_MIPS_LO16. In either case, free up the list and
381 * return an error.
382 */
383 if (me->arch.r_mips_hi16_list) {
384 free_relocation_chain(me->arch.r_mips_hi16_list);
385 me->arch.r_mips_hi16_list = NULL;
386 err = err ?: -ENOEXEC;
387 }
388
389 return err;
390}
391
392int apply_relocate(Elf_Shdr *sechdrs, const char *strtab,
393 unsigned int symindex, unsigned int relsec,
394 struct module *me)
395{
396 return __apply_relocate(sechdrs, strtab, symindex, relsec, me, false);
397}
398
399#ifdef CONFIG_MODULES_USE_ELF_RELA
400int apply_relocate_add(Elf_Shdr *sechdrs, const char *strtab,
401 unsigned int symindex, unsigned int relsec,
402 struct module *me)
403{
404 return __apply_relocate(sechdrs, strtab, symindex, relsec, me, true);
405}
406#endif /* CONFIG_MODULES_USE_ELF_RELA */
407
408/* Given an address, look for it in the module exception tables. */
409const struct exception_table_entry *search_module_dbetables(unsigned long addr)
410{
411 unsigned long flags;
412 const struct exception_table_entry *e = NULL;
413 struct mod_arch_specific *dbe;
414
415 spin_lock_irqsave(&dbe_lock, flags);
416 list_for_each_entry(dbe, &dbe_list, dbe_list) {
417 e = search_extable(dbe->dbe_start,
418 dbe->dbe_end - dbe->dbe_start, addr);
419 if (e)
420 break;
421 }
422 spin_unlock_irqrestore(&dbe_lock, flags);
423
424 /* Now, if we found one, we are running inside it now, hence
425 we cannot unload the module, hence no refcnt needed. */
426 return e;
427}
428
429/* Put in dbe list if necessary. */
430int module_finalize(const Elf_Ehdr *hdr,
431 const Elf_Shdr *sechdrs,
432 struct module *me)
433{
434 const Elf_Shdr *s;
435 char *secstrings = (void *)hdr + sechdrs[hdr->e_shstrndx].sh_offset;
436
437 /* Make jump label nops. */
438 jump_label_apply_nops(me);
439
440 INIT_LIST_HEAD(&me->arch.dbe_list);
441 for (s = sechdrs; s < sechdrs + hdr->e_shnum; s++) {
442 if (strcmp("__dbe_table", secstrings + s->sh_name) != 0)
443 continue;
444 me->arch.dbe_start = (void *)s->sh_addr;
445 me->arch.dbe_end = (void *)s->sh_addr + s->sh_size;
446 spin_lock_irq(&dbe_lock);
447 list_add(&me->arch.dbe_list, &dbe_list);
448 spin_unlock_irq(&dbe_lock);
449 }
450 return 0;
451}
452
453void module_arch_cleanup(struct module *mod)
454{
455 spin_lock_irq(&dbe_lock);
456 list_del(&mod->arch.dbe_list);
457 spin_unlock_irq(&dbe_lock);
458}
1/*
2 * This program is free software; you can redistribute it and/or modify
3 * it under the terms of the GNU General Public License as published by
4 * the Free Software Foundation; either version 2 of the License, or
5 * (at your option) any later version.
6 *
7 * This program is distributed in the hope that it will be useful,
8 * but WITHOUT ANY WARRANTY; without even the implied warranty of
9 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
10 * GNU General Public License for more details.
11 *
12 * You should have received a copy of the GNU General Public License
13 * along with this program; if not, write to the Free Software
14 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
15 *
16 * Copyright (C) 2001 Rusty Russell.
17 * Copyright (C) 2003, 2004 Ralf Baechle (ralf@linux-mips.org)
18 * Copyright (C) 2005 Thiemo Seufer
19 */
20
21#undef DEBUG
22
23#include <linux/moduleloader.h>
24#include <linux/elf.h>
25#include <linux/mm.h>
26#include <linux/vmalloc.h>
27#include <linux/slab.h>
28#include <linux/fs.h>
29#include <linux/string.h>
30#include <linux/kernel.h>
31#include <linux/spinlock.h>
32#include <linux/jump_label.h>
33
34#include <asm/pgtable.h> /* MODULE_START */
35
36struct mips_hi16 {
37 struct mips_hi16 *next;
38 Elf_Addr *addr;
39 Elf_Addr value;
40};
41
42static struct mips_hi16 *mips_hi16_list;
43
44static LIST_HEAD(dbe_list);
45static DEFINE_SPINLOCK(dbe_lock);
46
47#ifdef MODULE_START
48void *module_alloc(unsigned long size)
49{
50 return __vmalloc_node_range(size, 1, MODULE_START, MODULE_END,
51 GFP_KERNEL, PAGE_KERNEL, -1,
52 __builtin_return_address(0));
53}
54#endif
55
56static int apply_r_mips_none(struct module *me, u32 *location, Elf_Addr v)
57{
58 return 0;
59}
60
61static int apply_r_mips_32_rel(struct module *me, u32 *location, Elf_Addr v)
62{
63 *location += v;
64
65 return 0;
66}
67
68static int apply_r_mips_32_rela(struct module *me, u32 *location, Elf_Addr v)
69{
70 *location = v;
71
72 return 0;
73}
74
75static int apply_r_mips_26_rel(struct module *me, u32 *location, Elf_Addr v)
76{
77 if (v % 4) {
78 pr_err("module %s: dangerous R_MIPS_26 REL relocation\n",
79 me->name);
80 return -ENOEXEC;
81 }
82
83 if ((v & 0xf0000000) != (((unsigned long)location + 4) & 0xf0000000)) {
84 printk(KERN_ERR
85 "module %s: relocation overflow\n",
86 me->name);
87 return -ENOEXEC;
88 }
89
90 *location = (*location & ~0x03ffffff) |
91 ((*location + (v >> 2)) & 0x03ffffff);
92
93 return 0;
94}
95
96static int apply_r_mips_26_rela(struct module *me, u32 *location, Elf_Addr v)
97{
98 if (v % 4) {
99 pr_err("module %s: dangerous R_MIPS_26 RELArelocation\n",
100 me->name);
101 return -ENOEXEC;
102 }
103
104 if ((v & 0xf0000000) != (((unsigned long)location + 4) & 0xf0000000)) {
105 printk(KERN_ERR
106 "module %s: relocation overflow\n",
107 me->name);
108 return -ENOEXEC;
109 }
110
111 *location = (*location & ~0x03ffffff) | ((v >> 2) & 0x03ffffff);
112
113 return 0;
114}
115
116static int apply_r_mips_hi16_rel(struct module *me, u32 *location, Elf_Addr v)
117{
118 struct mips_hi16 *n;
119
120 /*
121 * We cannot relocate this one now because we don't know the value of
122 * the carry we need to add. Save the information, and let LO16 do the
123 * actual relocation.
124 */
125 n = kmalloc(sizeof *n, GFP_KERNEL);
126 if (!n)
127 return -ENOMEM;
128
129 n->addr = (Elf_Addr *)location;
130 n->value = v;
131 n->next = mips_hi16_list;
132 mips_hi16_list = n;
133
134 return 0;
135}
136
137static int apply_r_mips_hi16_rela(struct module *me, u32 *location, Elf_Addr v)
138{
139 *location = (*location & 0xffff0000) |
140 ((((long long) v + 0x8000LL) >> 16) & 0xffff);
141
142 return 0;
143}
144
145static int apply_r_mips_lo16_rel(struct module *me, u32 *location, Elf_Addr v)
146{
147 unsigned long insnlo = *location;
148 Elf_Addr val, vallo;
149
150 /* Sign extend the addend we extract from the lo insn. */
151 vallo = ((insnlo & 0xffff) ^ 0x8000) - 0x8000;
152
153 if (mips_hi16_list != NULL) {
154 struct mips_hi16 *l;
155
156 l = mips_hi16_list;
157 while (l != NULL) {
158 struct mips_hi16 *next;
159 unsigned long insn;
160
161 /*
162 * The value for the HI16 had best be the same.
163 */
164 if (v != l->value)
165 goto out_danger;
166
167 /*
168 * Do the HI16 relocation. Note that we actually don't
169 * need to know anything about the LO16 itself, except
170 * where to find the low 16 bits of the addend needed
171 * by the LO16.
172 */
173 insn = *l->addr;
174 val = ((insn & 0xffff) << 16) + vallo;
175 val += v;
176
177 /*
178 * Account for the sign extension that will happen in
179 * the low bits.
180 */
181 val = ((val >> 16) + ((val & 0x8000) != 0)) & 0xffff;
182
183 insn = (insn & ~0xffff) | val;
184 *l->addr = insn;
185
186 next = l->next;
187 kfree(l);
188 l = next;
189 }
190
191 mips_hi16_list = NULL;
192 }
193
194 /*
195 * Ok, we're done with the HI16 relocs. Now deal with the LO16.
196 */
197 val = v + vallo;
198 insnlo = (insnlo & ~0xffff) | (val & 0xffff);
199 *location = insnlo;
200
201 return 0;
202
203out_danger:
204 pr_err("module %s: dangerous R_MIPS_LO16 REL relocation\n", me->name);
205
206 return -ENOEXEC;
207}
208
209static int apply_r_mips_lo16_rela(struct module *me, u32 *location, Elf_Addr v)
210{
211 *location = (*location & 0xffff0000) | (v & 0xffff);
212
213 return 0;
214}
215
216static int apply_r_mips_64_rela(struct module *me, u32 *location, Elf_Addr v)
217{
218 *(Elf_Addr *)location = v;
219
220 return 0;
221}
222
223static int apply_r_mips_higher_rela(struct module *me, u32 *location,
224 Elf_Addr v)
225{
226 *location = (*location & 0xffff0000) |
227 ((((long long) v + 0x80008000LL) >> 32) & 0xffff);
228
229 return 0;
230}
231
232static int apply_r_mips_highest_rela(struct module *me, u32 *location,
233 Elf_Addr v)
234{
235 *location = (*location & 0xffff0000) |
236 ((((long long) v + 0x800080008000LL) >> 48) & 0xffff);
237
238 return 0;
239}
240
241static int (*reloc_handlers_rel[]) (struct module *me, u32 *location,
242 Elf_Addr v) = {
243 [R_MIPS_NONE] = apply_r_mips_none,
244 [R_MIPS_32] = apply_r_mips_32_rel,
245 [R_MIPS_26] = apply_r_mips_26_rel,
246 [R_MIPS_HI16] = apply_r_mips_hi16_rel,
247 [R_MIPS_LO16] = apply_r_mips_lo16_rel
248};
249
250static int (*reloc_handlers_rela[]) (struct module *me, u32 *location,
251 Elf_Addr v) = {
252 [R_MIPS_NONE] = apply_r_mips_none,
253 [R_MIPS_32] = apply_r_mips_32_rela,
254 [R_MIPS_26] = apply_r_mips_26_rela,
255 [R_MIPS_HI16] = apply_r_mips_hi16_rela,
256 [R_MIPS_LO16] = apply_r_mips_lo16_rela,
257 [R_MIPS_64] = apply_r_mips_64_rela,
258 [R_MIPS_HIGHER] = apply_r_mips_higher_rela,
259 [R_MIPS_HIGHEST] = apply_r_mips_highest_rela
260};
261
262int apply_relocate(Elf_Shdr *sechdrs, const char *strtab,
263 unsigned int symindex, unsigned int relsec,
264 struct module *me)
265{
266 Elf_Mips_Rel *rel = (void *) sechdrs[relsec].sh_addr;
267 Elf_Sym *sym;
268 u32 *location;
269 unsigned int i;
270 Elf_Addr v;
271 int res;
272
273 pr_debug("Applying relocate section %u to %u\n", relsec,
274 sechdrs[relsec].sh_info);
275
276 for (i = 0; i < sechdrs[relsec].sh_size / sizeof(*rel); i++) {
277 /* This is where to make the change */
278 location = (void *)sechdrs[sechdrs[relsec].sh_info].sh_addr
279 + rel[i].r_offset;
280 /* This is the symbol it is referring to */
281 sym = (Elf_Sym *)sechdrs[symindex].sh_addr
282 + ELF_MIPS_R_SYM(rel[i]);
283 if (IS_ERR_VALUE(sym->st_value)) {
284 /* Ignore unresolved weak symbol */
285 if (ELF_ST_BIND(sym->st_info) == STB_WEAK)
286 continue;
287 printk(KERN_WARNING "%s: Unknown symbol %s\n",
288 me->name, strtab + sym->st_name);
289 return -ENOENT;
290 }
291
292 v = sym->st_value;
293
294 res = reloc_handlers_rel[ELF_MIPS_R_TYPE(rel[i])](me, location, v);
295 if (res)
296 return res;
297 }
298
299 return 0;
300}
301
302int apply_relocate_add(Elf_Shdr *sechdrs, const char *strtab,
303 unsigned int symindex, unsigned int relsec,
304 struct module *me)
305{
306 Elf_Mips_Rela *rel = (void *) sechdrs[relsec].sh_addr;
307 Elf_Sym *sym;
308 u32 *location;
309 unsigned int i;
310 Elf_Addr v;
311 int res;
312
313 pr_debug("Applying relocate section %u to %u\n", relsec,
314 sechdrs[relsec].sh_info);
315
316 for (i = 0; i < sechdrs[relsec].sh_size / sizeof(*rel); i++) {
317 /* This is where to make the change */
318 location = (void *)sechdrs[sechdrs[relsec].sh_info].sh_addr
319 + rel[i].r_offset;
320 /* This is the symbol it is referring to */
321 sym = (Elf_Sym *)sechdrs[symindex].sh_addr
322 + ELF_MIPS_R_SYM(rel[i]);
323 if (IS_ERR_VALUE(sym->st_value)) {
324 /* Ignore unresolved weak symbol */
325 if (ELF_ST_BIND(sym->st_info) == STB_WEAK)
326 continue;
327 printk(KERN_WARNING "%s: Unknown symbol %s\n",
328 me->name, strtab + sym->st_name);
329 return -ENOENT;
330 }
331
332 v = sym->st_value + rel[i].r_addend;
333
334 res = reloc_handlers_rela[ELF_MIPS_R_TYPE(rel[i])](me, location, v);
335 if (res)
336 return res;
337 }
338
339 return 0;
340}
341
342/* Given an address, look for it in the module exception tables. */
343const struct exception_table_entry *search_module_dbetables(unsigned long addr)
344{
345 unsigned long flags;
346 const struct exception_table_entry *e = NULL;
347 struct mod_arch_specific *dbe;
348
349 spin_lock_irqsave(&dbe_lock, flags);
350 list_for_each_entry(dbe, &dbe_list, dbe_list) {
351 e = search_extable(dbe->dbe_start, dbe->dbe_end - 1, addr);
352 if (e)
353 break;
354 }
355 spin_unlock_irqrestore(&dbe_lock, flags);
356
357 /* Now, if we found one, we are running inside it now, hence
358 we cannot unload the module, hence no refcnt needed. */
359 return e;
360}
361
362/* Put in dbe list if necessary. */
363int module_finalize(const Elf_Ehdr *hdr,
364 const Elf_Shdr *sechdrs,
365 struct module *me)
366{
367 const Elf_Shdr *s;
368 char *secstrings = (void *)hdr + sechdrs[hdr->e_shstrndx].sh_offset;
369
370 /* Make jump label nops. */
371 jump_label_apply_nops(me);
372
373 INIT_LIST_HEAD(&me->arch.dbe_list);
374 for (s = sechdrs; s < sechdrs + hdr->e_shnum; s++) {
375 if (strcmp("__dbe_table", secstrings + s->sh_name) != 0)
376 continue;
377 me->arch.dbe_start = (void *)s->sh_addr;
378 me->arch.dbe_end = (void *)s->sh_addr + s->sh_size;
379 spin_lock_irq(&dbe_lock);
380 list_add(&me->arch.dbe_list, &dbe_list);
381 spin_unlock_irq(&dbe_lock);
382 }
383 return 0;
384}
385
386void module_arch_cleanup(struct module *mod)
387{
388 spin_lock_irq(&dbe_lock);
389 list_del(&mod->arch.dbe_list);
390 spin_unlock_irq(&dbe_lock);
391}