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v4.6
 
  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/numa.h>
 27#include <linux/vmalloc.h>
 28#include <linux/slab.h>
 29#include <linux/fs.h>
 30#include <linux/string.h>
 31#include <linux/kernel.h>
 32#include <linux/spinlock.h>
 33#include <linux/jump_label.h>
 34
 35#include <asm/pgtable.h>	/* MODULE_START */
 36
 37struct mips_hi16 {
 38	struct mips_hi16 *next;
 39	Elf_Addr *addr;
 40	Elf_Addr value;
 41};
 42
 43static LIST_HEAD(dbe_list);
 44static DEFINE_SPINLOCK(dbe_lock);
 45
 46#ifdef MODULE_START
 47void *module_alloc(unsigned long size)
 48{
 49	return __vmalloc_node_range(size, 1, MODULE_START, MODULE_END,
 50				GFP_KERNEL, PAGE_KERNEL, 0, NUMA_NO_NODE,
 51				__builtin_return_address(0));
 52}
 53#endif
 54
 55int apply_r_mips_none(struct module *me, u32 *location, Elf_Addr v)
 
 56{
 57	return 0;
 58}
 59
 60static int apply_r_mips_32_rel(struct module *me, u32 *location, Elf_Addr v)
 
 61{
 62	*location += v;
 63
 64	return 0;
 65}
 66
 67static int apply_r_mips_26_rel(struct module *me, u32 *location, Elf_Addr v)
 
 68{
 69	if (v % 4) {
 70		pr_err("module %s: dangerous R_MIPS_26 REL relocation\n",
 71		       me->name);
 72		return -ENOEXEC;
 73	}
 74
 75	if ((v & 0xf0000000) != (((unsigned long)location + 4) & 0xf0000000)) {
 76		printk(KERN_ERR
 77		       "module %s: relocation overflow\n",
 78		       me->name);
 79		return -ENOEXEC;
 80	}
 81
 82	*location = (*location & ~0x03ffffff) |
 83		    ((*location + (v >> 2)) & 0x03ffffff);
 84
 85	return 0;
 86}
 87
 88static int apply_r_mips_hi16_rel(struct module *me, u32 *location, Elf_Addr v)
 
 89{
 90	struct mips_hi16 *n;
 91
 
 
 
 
 
 
 92	/*
 93	 * We cannot relocate this one now because we don't know the value of
 94	 * the carry we need to add.  Save the information, and let LO16 do the
 95	 * actual relocation.
 96	 */
 97	n = kmalloc(sizeof *n, GFP_KERNEL);
 98	if (!n)
 99		return -ENOMEM;
100
101	n->addr = (Elf_Addr *)location;
102	n->value = v;
103	n->next = me->arch.r_mips_hi16_list;
104	me->arch.r_mips_hi16_list = n;
105
106	return 0;
107}
108
109static void free_relocation_chain(struct mips_hi16 *l)
110{
111	struct mips_hi16 *next;
112
113	while (l) {
114		next = l->next;
115		kfree(l);
116		l = next;
117	}
118}
119
120static int apply_r_mips_lo16_rel(struct module *me, u32 *location, Elf_Addr v)
 
121{
122	unsigned long insnlo = *location;
123	struct mips_hi16 *l;
124	Elf_Addr val, vallo;
125
 
 
 
 
 
126	/* Sign extend the addend we extract from the lo insn.	*/
127	vallo = ((insnlo & 0xffff) ^ 0x8000) - 0x8000;
128
129	if (me->arch.r_mips_hi16_list != NULL) {
130		l = me->arch.r_mips_hi16_list;
131		while (l != NULL) {
132			struct mips_hi16 *next;
133			unsigned long insn;
134
135			/*
136			 * The value for the HI16 had best be the same.
137			 */
138			if (v != l->value)
139				goto out_danger;
140
141			/*
142			 * Do the HI16 relocation.  Note that we actually don't
143			 * need to know anything about the LO16 itself, except
144			 * where to find the low 16 bits of the addend needed
145			 * by the LO16.
146			 */
147			insn = *l->addr;
148			val = ((insn & 0xffff) << 16) + vallo;
149			val += v;
150
151			/*
152			 * Account for the sign extension that will happen in
153			 * the low bits.
154			 */
155			val = ((val >> 16) + ((val & 0x8000) != 0)) & 0xffff;
156
157			insn = (insn & ~0xffff) | val;
158			*l->addr = insn;
159
160			next = l->next;
161			kfree(l);
162			l = next;
163		}
164
165		me->arch.r_mips_hi16_list = NULL;
166	}
167
168	/*
169	 * Ok, we're done with the HI16 relocs.	 Now deal with the LO16.
170	 */
171	val = v + vallo;
172	insnlo = (insnlo & ~0xffff) | (val & 0xffff);
173	*location = insnlo;
174
175	return 0;
176
177out_danger:
178	free_relocation_chain(l);
179	me->arch.r_mips_hi16_list = NULL;
180
181	pr_err("module %s: dangerous R_MIPS_LO16 REL relocation\n", me->name);
182
183	return -ENOEXEC;
184}
185
186static int (*reloc_handlers_rel[]) (struct module *me, u32 *location,
187				Elf_Addr v) = {
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
188	[R_MIPS_NONE]		= apply_r_mips_none,
189	[R_MIPS_32]		= apply_r_mips_32_rel,
190	[R_MIPS_26]		= apply_r_mips_26_rel,
191	[R_MIPS_HI16]		= apply_r_mips_hi16_rel,
192	[R_MIPS_LO16]		= apply_r_mips_lo16_rel
 
 
 
 
 
 
193};
194
195int apply_relocate(Elf_Shdr *sechdrs, const char *strtab,
196		   unsigned int symindex, unsigned int relsec,
197		   struct module *me)
198{
199	Elf_Mips_Rel *rel = (void *) sechdrs[relsec].sh_addr;
200	int (*handler)(struct module *me, u32 *location, Elf_Addr v);
 
 
 
201	Elf_Sym *sym;
202	u32 *location;
203	unsigned int i, type;
204	Elf_Addr v;
205	int res;
 
206
207	pr_debug("Applying relocate section %u to %u\n", relsec,
208	       sechdrs[relsec].sh_info);
209
 
 
210	me->arch.r_mips_hi16_list = NULL;
211	for (i = 0; i < sechdrs[relsec].sh_size / sizeof(*rel); i++) {
212		/* This is where to make the change */
213		location = (void *)sechdrs[sechdrs[relsec].sh_info].sh_addr
214			+ rel[i].r_offset;
215		/* This is the symbol it is referring to */
216		sym = (Elf_Sym *)sechdrs[symindex].sh_addr
217			+ ELF_MIPS_R_SYM(rel[i]);
218		if (IS_ERR_VALUE(sym->st_value)) {
219			/* Ignore unresolved weak symbol */
220			if (ELF_ST_BIND(sym->st_info) == STB_WEAK)
221				continue;
222			printk(KERN_WARNING "%s: Unknown symbol %s\n",
223			       me->name, strtab + sym->st_name);
224			return -ENOENT;
 
225		}
226
227		type = ELF_MIPS_R_TYPE(rel[i]);
228
229		if (type < ARRAY_SIZE(reloc_handlers_rel))
230			handler = reloc_handlers_rel[type];
231		else
232			handler = NULL;
233
234		if (!handler) {
235			pr_err("%s: Unknown relocation type %u\n",
236			       me->name, type);
237			return -EINVAL;
 
 
 
 
 
 
 
 
 
 
 
238		}
239
240		v = sym->st_value;
241		res = handler(me, location, v);
242		if (res)
243			return res;
244	}
245
 
246	/*
247	 * Normally the hi16 list should be deallocated at this point.	A
248	 * malformed binary however could contain a series of R_MIPS_HI16
249	 * relocations not followed by a R_MIPS_LO16 relocation.  In that
250	 * case, free up the list and return an error.
 
 
251	 */
252	if (me->arch.r_mips_hi16_list) {
253		free_relocation_chain(me->arch.r_mips_hi16_list);
254		me->arch.r_mips_hi16_list = NULL;
255
256		return -ENOEXEC;
257	}
258
259	return 0;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
260}
 
261
262/* Given an address, look for it in the module exception tables. */
263const struct exception_table_entry *search_module_dbetables(unsigned long addr)
264{
265	unsigned long flags;
266	const struct exception_table_entry *e = NULL;
267	struct mod_arch_specific *dbe;
268
269	spin_lock_irqsave(&dbe_lock, flags);
270	list_for_each_entry(dbe, &dbe_list, dbe_list) {
271		e = search_extable(dbe->dbe_start, dbe->dbe_end - 1, addr);
 
272		if (e)
273			break;
274	}
275	spin_unlock_irqrestore(&dbe_lock, flags);
276
277	/* Now, if we found one, we are running inside it now, hence
278	   we cannot unload the module, hence no refcnt needed. */
279	return e;
280}
281
282/* Put in dbe list if necessary. */
283int module_finalize(const Elf_Ehdr *hdr,
284		    const Elf_Shdr *sechdrs,
285		    struct module *me)
286{
287	const Elf_Shdr *s;
288	char *secstrings = (void *)hdr + sechdrs[hdr->e_shstrndx].sh_offset;
289
290	/* Make jump label nops. */
291	jump_label_apply_nops(me);
292
293	INIT_LIST_HEAD(&me->arch.dbe_list);
294	for (s = sechdrs; s < sechdrs + hdr->e_shnum; s++) {
295		if (strcmp("__dbe_table", secstrings + s->sh_name) != 0)
296			continue;
297		me->arch.dbe_start = (void *)s->sh_addr;
298		me->arch.dbe_end = (void *)s->sh_addr + s->sh_size;
299		spin_lock_irq(&dbe_lock);
300		list_add(&me->arch.dbe_list, &dbe_list);
301		spin_unlock_irq(&dbe_lock);
302	}
303	return 0;
304}
305
306void module_arch_cleanup(struct module *mod)
307{
308	spin_lock_irq(&dbe_lock);
309	list_del(&mod->arch.dbe_list);
310	spin_unlock_irq(&dbe_lock);
311}
v5.4
  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}