1 // SPDX-License-Identifier: GPL-2.0-or-later 1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /* 2 /*
3 * Module kallsyms support 3 * Module kallsyms support
4 * 4 *
5 * Copyright (C) 2010 Rusty Russell 5 * Copyright (C) 2010 Rusty Russell
6 */ 6 */
7 7
8 #include <linux/module.h> 8 #include <linux/module.h>
9 #include <linux/module_symbol.h> 9 #include <linux/module_symbol.h>
10 #include <linux/kallsyms.h> 10 #include <linux/kallsyms.h>
11 #include <linux/buildid.h> 11 #include <linux/buildid.h>
12 #include <linux/bsearch.h> 12 #include <linux/bsearch.h>
13 #include "internal.h" 13 #include "internal.h"
14 14
15 /* Lookup exported symbol in given range of ke 15 /* Lookup exported symbol in given range of kernel_symbols */
16 static const struct kernel_symbol *lookup_expo 16 static const struct kernel_symbol *lookup_exported_symbol(const char *name,
17 17 const struct kernel_symbol *start,
18 18 const struct kernel_symbol *stop)
19 { 19 {
20 return bsearch(name, start, stop - sta 20 return bsearch(name, start, stop - start,
21 sizeof(struct kernel_s 21 sizeof(struct kernel_symbol), cmp_name);
22 } 22 }
23 23
24 static int is_exported(const char *name, unsig 24 static int is_exported(const char *name, unsigned long value,
25 const struct module *mo 25 const struct module *mod)
26 { 26 {
27 const struct kernel_symbol *ks; 27 const struct kernel_symbol *ks;
28 28
29 if (!mod) 29 if (!mod)
30 ks = lookup_exported_symbol(na 30 ks = lookup_exported_symbol(name, __start___ksymtab, __stop___ksymtab);
31 else 31 else
32 ks = lookup_exported_symbol(na 32 ks = lookup_exported_symbol(name, mod->syms, mod->syms + mod->num_syms);
33 33
34 return ks && kernel_symbol_value(ks) = 34 return ks && kernel_symbol_value(ks) == value;
35 } 35 }
36 36
37 /* As per nm */ 37 /* As per nm */
38 static char elf_type(const Elf_Sym *sym, const 38 static char elf_type(const Elf_Sym *sym, const struct load_info *info)
39 { 39 {
40 const Elf_Shdr *sechdrs = info->sechdr 40 const Elf_Shdr *sechdrs = info->sechdrs;
41 41
42 if (ELF_ST_BIND(sym->st_info) == STB_W 42 if (ELF_ST_BIND(sym->st_info) == STB_WEAK) {
43 if (ELF_ST_TYPE(sym->st_info) 43 if (ELF_ST_TYPE(sym->st_info) == STT_OBJECT)
44 return 'v'; 44 return 'v';
45 else 45 else
46 return 'w'; 46 return 'w';
47 } 47 }
48 if (sym->st_shndx == SHN_UNDEF) 48 if (sym->st_shndx == SHN_UNDEF)
49 return 'U'; 49 return 'U';
50 if (sym->st_shndx == SHN_ABS || sym->s 50 if (sym->st_shndx == SHN_ABS || sym->st_shndx == info->index.pcpu)
51 return 'a'; 51 return 'a';
52 if (sym->st_shndx >= SHN_LORESERVE) 52 if (sym->st_shndx >= SHN_LORESERVE)
53 return '?'; 53 return '?';
54 if (sechdrs[sym->st_shndx].sh_flags & 54 if (sechdrs[sym->st_shndx].sh_flags & SHF_EXECINSTR)
55 return 't'; 55 return 't';
56 if (sechdrs[sym->st_shndx].sh_flags & 56 if (sechdrs[sym->st_shndx].sh_flags & SHF_ALLOC &&
57 sechdrs[sym->st_shndx].sh_type != 57 sechdrs[sym->st_shndx].sh_type != SHT_NOBITS) {
58 if (!(sechdrs[sym->st_shndx].s 58 if (!(sechdrs[sym->st_shndx].sh_flags & SHF_WRITE))
59 return 'r'; 59 return 'r';
60 else if (sechdrs[sym->st_shndx 60 else if (sechdrs[sym->st_shndx].sh_flags & ARCH_SHF_SMALL)
61 return 'g'; 61 return 'g';
62 else 62 else
63 return 'd'; 63 return 'd';
64 } 64 }
65 if (sechdrs[sym->st_shndx].sh_type == 65 if (sechdrs[sym->st_shndx].sh_type == SHT_NOBITS) {
66 if (sechdrs[sym->st_shndx].sh_ 66 if (sechdrs[sym->st_shndx].sh_flags & ARCH_SHF_SMALL)
67 return 's'; 67 return 's';
68 else 68 else
69 return 'b'; 69 return 'b';
70 } 70 }
71 if (strstarts(info->secstrings + sechd 71 if (strstarts(info->secstrings + sechdrs[sym->st_shndx].sh_name,
72 ".debug")) { 72 ".debug")) {
73 return 'n'; 73 return 'n';
74 } 74 }
75 return '?'; 75 return '?';
76 } 76 }
77 77
78 static bool is_core_symbol(const Elf_Sym *src, 78 static bool is_core_symbol(const Elf_Sym *src, const Elf_Shdr *sechdrs,
79 unsigned int shnum, 79 unsigned int shnum, unsigned int pcpundx)
80 { 80 {
81 const Elf_Shdr *sec; 81 const Elf_Shdr *sec;
82 enum mod_mem_type type; 82 enum mod_mem_type type;
83 83
84 if (src->st_shndx == SHN_UNDEF || 84 if (src->st_shndx == SHN_UNDEF ||
85 src->st_shndx >= shnum || 85 src->st_shndx >= shnum ||
86 !src->st_name) 86 !src->st_name)
87 return false; 87 return false;
88 88
89 #ifdef CONFIG_KALLSYMS_ALL 89 #ifdef CONFIG_KALLSYMS_ALL
90 if (src->st_shndx == pcpundx) 90 if (src->st_shndx == pcpundx)
91 return true; 91 return true;
92 #endif 92 #endif
93 93
94 sec = sechdrs + src->st_shndx; 94 sec = sechdrs + src->st_shndx;
95 type = sec->sh_entsize >> SH_ENTSIZE_T 95 type = sec->sh_entsize >> SH_ENTSIZE_TYPE_SHIFT;
96 if (!(sec->sh_flags & SHF_ALLOC) 96 if (!(sec->sh_flags & SHF_ALLOC)
97 #ifndef CONFIG_KALLSYMS_ALL 97 #ifndef CONFIG_KALLSYMS_ALL
98 || !(sec->sh_flags & SHF_EXECINSTR 98 || !(sec->sh_flags & SHF_EXECINSTR)
99 #endif 99 #endif
100 || mod_mem_type_is_init(type)) 100 || mod_mem_type_is_init(type))
101 return false; 101 return false;
102 102
103 return true; 103 return true;
104 } 104 }
105 105
106 /* 106 /*
107 * We only allocate and copy the strings neede 107 * We only allocate and copy the strings needed by the parts of symtab
108 * we keep. This is simple, but has the effec 108 * we keep. This is simple, but has the effect of making multiple
109 * copies of duplicates. We could be more sop 109 * copies of duplicates. We could be more sophisticated, see
110 * linux-kernel thread starting with 110 * linux-kernel thread starting with
111 * <73defb5e4bca04a6431392cc341112b1@localhost 111 * <73defb5e4bca04a6431392cc341112b1@localhost>.
112 */ 112 */
113 void layout_symtab(struct module *mod, struct 113 void layout_symtab(struct module *mod, struct load_info *info)
114 { 114 {
115 Elf_Shdr *symsect = info->sechdrs + in 115 Elf_Shdr *symsect = info->sechdrs + info->index.sym;
116 Elf_Shdr *strsect = info->sechdrs + in 116 Elf_Shdr *strsect = info->sechdrs + info->index.str;
117 const Elf_Sym *src; 117 const Elf_Sym *src;
118 unsigned int i, nsrc, ndst, strtab_siz 118 unsigned int i, nsrc, ndst, strtab_size = 0;
119 struct module_memory *mod_mem_data = & 119 struct module_memory *mod_mem_data = &mod->mem[MOD_DATA];
120 struct module_memory *mod_mem_init_dat 120 struct module_memory *mod_mem_init_data = &mod->mem[MOD_INIT_DATA];
121 121
122 /* Put symbol section at end of init p 122 /* Put symbol section at end of init part of module. */
123 symsect->sh_flags |= SHF_ALLOC; 123 symsect->sh_flags |= SHF_ALLOC;
124 symsect->sh_entsize = module_get_offse 124 symsect->sh_entsize = module_get_offset_and_type(mod, MOD_INIT_DATA,
125 125 symsect, info->index.sym);
126 pr_debug("\t%s\n", info->secstrings + 126 pr_debug("\t%s\n", info->secstrings + symsect->sh_name);
127 127
128 src = (void *)info->hdr + symsect->sh_ 128 src = (void *)info->hdr + symsect->sh_offset;
129 nsrc = symsect->sh_size / sizeof(*src) 129 nsrc = symsect->sh_size / sizeof(*src);
130 130
131 /* Compute total space required for th 131 /* Compute total space required for the core symbols' strtab. */
132 for (ndst = i = 0; i < nsrc; i++) { 132 for (ndst = i = 0; i < nsrc; i++) {
133 if (i == 0 || is_livepatch_mod 133 if (i == 0 || is_livepatch_module(mod) ||
134 is_core_symbol(src + i, in 134 is_core_symbol(src + i, info->sechdrs, info->hdr->e_shnum,
135 info->index 135 info->index.pcpu)) {
136 strtab_size += strlen( 136 strtab_size += strlen(&info->strtab[src[i].st_name]) + 1;
137 ndst++; 137 ndst++;
138 } 138 }
139 } 139 }
140 140
141 /* Append room for core symbols at end 141 /* Append room for core symbols at end of core part. */
142 info->symoffs = ALIGN(mod_mem_data->si 142 info->symoffs = ALIGN(mod_mem_data->size, symsect->sh_addralign ?: 1);
143 info->stroffs = mod_mem_data->size = i 143 info->stroffs = mod_mem_data->size = info->symoffs + ndst * sizeof(Elf_Sym);
144 mod_mem_data->size += strtab_size; 144 mod_mem_data->size += strtab_size;
145 /* Note add_kallsyms() computes strtab 145 /* Note add_kallsyms() computes strtab_size as core_typeoffs - stroffs */
146 info->core_typeoffs = mod_mem_data->si 146 info->core_typeoffs = mod_mem_data->size;
147 mod_mem_data->size += ndst * sizeof(ch 147 mod_mem_data->size += ndst * sizeof(char);
148 148
149 /* Put string table section at end of 149 /* Put string table section at end of init part of module. */
150 strsect->sh_flags |= SHF_ALLOC; 150 strsect->sh_flags |= SHF_ALLOC;
151 strsect->sh_entsize = module_get_offse 151 strsect->sh_entsize = module_get_offset_and_type(mod, MOD_INIT_DATA,
152 152 strsect, info->index.str);
153 pr_debug("\t%s\n", info->secstrings + 153 pr_debug("\t%s\n", info->secstrings + strsect->sh_name);
154 154
155 /* We'll tack temporary mod_kallsyms o 155 /* We'll tack temporary mod_kallsyms on the end. */
156 mod_mem_init_data->size = ALIGN(mod_me 156 mod_mem_init_data->size = ALIGN(mod_mem_init_data->size,
157 __alig 157 __alignof__(struct mod_kallsyms));
158 info->mod_kallsyms_init_off = mod_mem_ 158 info->mod_kallsyms_init_off = mod_mem_init_data->size;
159 159
160 mod_mem_init_data->size += sizeof(stru 160 mod_mem_init_data->size += sizeof(struct mod_kallsyms);
161 info->init_typeoffs = mod_mem_init_dat 161 info->init_typeoffs = mod_mem_init_data->size;
162 mod_mem_init_data->size += nsrc * size 162 mod_mem_init_data->size += nsrc * sizeof(char);
163 } 163 }
164 164
165 /* 165 /*
166 * We use the full symtab and strtab which lay 166 * We use the full symtab and strtab which layout_symtab arranged to
167 * be appended to the init section. Later we 167 * be appended to the init section. Later we switch to the cut-down
168 * core-only ones. 168 * core-only ones.
169 */ 169 */
170 void add_kallsyms(struct module *mod, const st 170 void add_kallsyms(struct module *mod, const struct load_info *info)
171 { 171 {
172 unsigned int i, ndst; 172 unsigned int i, ndst;
173 const Elf_Sym *src; 173 const Elf_Sym *src;
174 Elf_Sym *dst; 174 Elf_Sym *dst;
175 char *s; 175 char *s;
176 Elf_Shdr *symsec = &info->sechdrs[info 176 Elf_Shdr *symsec = &info->sechdrs[info->index.sym];
177 unsigned long strtab_size; 177 unsigned long strtab_size;
178 void *data_base = mod->mem[MOD_DATA].b 178 void *data_base = mod->mem[MOD_DATA].base;
179 void *init_data_base = mod->mem[MOD_IN 179 void *init_data_base = mod->mem[MOD_INIT_DATA].base;
180 180
181 /* Set up to point into init section. 181 /* Set up to point into init section. */
182 mod->kallsyms = (void __rcu *)init_dat 182 mod->kallsyms = (void __rcu *)init_data_base +
183 info->mod_kallsyms_init_off; 183 info->mod_kallsyms_init_off;
184 184
185 rcu_read_lock(); 185 rcu_read_lock();
186 /* The following is safe since this po 186 /* The following is safe since this pointer cannot change */
187 rcu_dereference(mod->kallsyms)->symtab 187 rcu_dereference(mod->kallsyms)->symtab = (void *)symsec->sh_addr;
188 rcu_dereference(mod->kallsyms)->num_sy 188 rcu_dereference(mod->kallsyms)->num_symtab = symsec->sh_size / sizeof(Elf_Sym);
189 /* Make sure we get permanent strtab: 189 /* Make sure we get permanent strtab: don't use info->strtab. */
190 rcu_dereference(mod->kallsyms)->strtab 190 rcu_dereference(mod->kallsyms)->strtab =
191 (void *)info->sechdrs[info->in 191 (void *)info->sechdrs[info->index.str].sh_addr;
192 rcu_dereference(mod->kallsyms)->typeta 192 rcu_dereference(mod->kallsyms)->typetab = init_data_base + info->init_typeoffs;
193 193
194 /* 194 /*
195 * Now populate the cut down core kall 195 * Now populate the cut down core kallsyms for after init
196 * and set types up while we still hav 196 * and set types up while we still have access to sections.
197 */ 197 */
198 mod->core_kallsyms.symtab = dst = data 198 mod->core_kallsyms.symtab = dst = data_base + info->symoffs;
199 mod->core_kallsyms.strtab = s = data_b 199 mod->core_kallsyms.strtab = s = data_base + info->stroffs;
200 mod->core_kallsyms.typetab = data_base 200 mod->core_kallsyms.typetab = data_base + info->core_typeoffs;
201 strtab_size = info->core_typeoffs - in 201 strtab_size = info->core_typeoffs - info->stroffs;
202 src = rcu_dereference(mod->kallsyms)-> 202 src = rcu_dereference(mod->kallsyms)->symtab;
203 for (ndst = i = 0; i < rcu_dereference 203 for (ndst = i = 0; i < rcu_dereference(mod->kallsyms)->num_symtab; i++) {
204 rcu_dereference(mod->kallsyms) 204 rcu_dereference(mod->kallsyms)->typetab[i] = elf_type(src + i, info);
205 if (i == 0 || is_livepatch_mod 205 if (i == 0 || is_livepatch_module(mod) ||
206 is_core_symbol(src + i, in 206 is_core_symbol(src + i, info->sechdrs, info->hdr->e_shnum,
207 info->index 207 info->index.pcpu)) {
208 ssize_t ret; 208 ssize_t ret;
209 209
210 mod->core_kallsyms.typ 210 mod->core_kallsyms.typetab[ndst] =
211 rcu_dereference(mo 211 rcu_dereference(mod->kallsyms)->typetab[i];
212 dst[ndst] = src[i]; 212 dst[ndst] = src[i];
213 dst[ndst++].st_name = 213 dst[ndst++].st_name = s - mod->core_kallsyms.strtab;
214 ret = strscpy(s, 214 ret = strscpy(s,
215 &rcu_der 215 &rcu_dereference(mod->kallsyms)->strtab[src[i].st_name],
216 strtab_s 216 strtab_size);
217 if (ret < 0) 217 if (ret < 0)
218 break; 218 break;
219 s += ret + 1; 219 s += ret + 1;
220 strtab_size -= ret + 1 220 strtab_size -= ret + 1;
221 } 221 }
222 } 222 }
223 rcu_read_unlock(); 223 rcu_read_unlock();
224 mod->core_kallsyms.num_symtab = ndst; 224 mod->core_kallsyms.num_symtab = ndst;
225 } 225 }
226 226
227 #if IS_ENABLED(CONFIG_STACKTRACE_BUILD_ID) 227 #if IS_ENABLED(CONFIG_STACKTRACE_BUILD_ID)
228 void init_build_id(struct module *mod, const s 228 void init_build_id(struct module *mod, const struct load_info *info)
229 { 229 {
230 const Elf_Shdr *sechdr; 230 const Elf_Shdr *sechdr;
231 unsigned int i; 231 unsigned int i;
232 232
233 for (i = 0; i < info->hdr->e_shnum; i+ 233 for (i = 0; i < info->hdr->e_shnum; i++) {
234 sechdr = &info->sechdrs[i]; 234 sechdr = &info->sechdrs[i];
235 if (!sect_empty(sechdr) && sec 235 if (!sect_empty(sechdr) && sechdr->sh_type == SHT_NOTE &&
236 !build_id_parse_buf((void 236 !build_id_parse_buf((void *)sechdr->sh_addr, mod->build_id,
237 sechdr 237 sechdr->sh_size))
238 break; 238 break;
239 } 239 }
240 } 240 }
241 #else 241 #else
242 void init_build_id(struct module *mod, const s 242 void init_build_id(struct module *mod, const struct load_info *info)
243 { 243 {
244 } 244 }
245 #endif 245 #endif
246 246
247 static const char *kallsyms_symbol_name(struct 247 static const char *kallsyms_symbol_name(struct mod_kallsyms *kallsyms, unsigned int symnum)
248 { 248 {
249 return kallsyms->strtab + kallsyms->sy 249 return kallsyms->strtab + kallsyms->symtab[symnum].st_name;
250 } 250 }
251 251
252 /* 252 /*
253 * Given a module and address, find the corres 253 * Given a module and address, find the corresponding symbol and return its name
254 * while providing its size and offset if need 254 * while providing its size and offset if needed.
255 */ 255 */
256 static const char *find_kallsyms_symbol(struct 256 static const char *find_kallsyms_symbol(struct module *mod,
257 unsign 257 unsigned long addr,
258 unsign 258 unsigned long *size,
259 unsign 259 unsigned long *offset)
260 { 260 {
261 unsigned int i, best = 0; 261 unsigned int i, best = 0;
262 unsigned long nextval, bestval; 262 unsigned long nextval, bestval;
263 struct mod_kallsyms *kallsyms = rcu_de 263 struct mod_kallsyms *kallsyms = rcu_dereference_sched(mod->kallsyms);
264 struct module_memory *mod_mem; 264 struct module_memory *mod_mem;
265 265
266 /* At worse, next value is at end of m 266 /* At worse, next value is at end of module */
267 if (within_module_init(addr, mod)) 267 if (within_module_init(addr, mod))
268 mod_mem = &mod->mem[MOD_INIT_T 268 mod_mem = &mod->mem[MOD_INIT_TEXT];
269 else 269 else
270 mod_mem = &mod->mem[MOD_TEXT]; 270 mod_mem = &mod->mem[MOD_TEXT];
271 271
272 nextval = (unsigned long)mod_mem->base 272 nextval = (unsigned long)mod_mem->base + mod_mem->size;
273 273
274 bestval = kallsyms_symbol_value(&kalls 274 bestval = kallsyms_symbol_value(&kallsyms->symtab[best]);
275 275
276 /* 276 /*
277 * Scan for closest preceding symbol, 277 * Scan for closest preceding symbol, and next symbol. (ELF
278 * starts real symbols at 1). 278 * starts real symbols at 1).
279 */ 279 */
280 for (i = 1; i < kallsyms->num_symtab; 280 for (i = 1; i < kallsyms->num_symtab; i++) {
281 const Elf_Sym *sym = &kallsyms 281 const Elf_Sym *sym = &kallsyms->symtab[i];
282 unsigned long thisval = kallsy 282 unsigned long thisval = kallsyms_symbol_value(sym);
283 283
284 if (sym->st_shndx == SHN_UNDEF 284 if (sym->st_shndx == SHN_UNDEF)
285 continue; 285 continue;
286 286
287 /* 287 /*
288 * We ignore unnamed symbols: 288 * We ignore unnamed symbols: they're uninformative
289 * and inserted at a whim. 289 * and inserted at a whim.
290 */ 290 */
291 if (*kallsyms_symbol_name(kall 291 if (*kallsyms_symbol_name(kallsyms, i) == '\0' ||
292 is_mapping_symbol(kallsyms 292 is_mapping_symbol(kallsyms_symbol_name(kallsyms, i)))
293 continue; 293 continue;
294 294
295 if (thisval <= addr && thisval 295 if (thisval <= addr && thisval > bestval) {
296 best = i; 296 best = i;
297 bestval = thisval; 297 bestval = thisval;
298 } 298 }
299 if (thisval > addr && thisval 299 if (thisval > addr && thisval < nextval)
300 nextval = thisval; 300 nextval = thisval;
301 } 301 }
302 302
303 if (!best) 303 if (!best)
304 return NULL; 304 return NULL;
305 305
306 if (size) 306 if (size)
307 *size = nextval - bestval; 307 *size = nextval - bestval;
308 if (offset) 308 if (offset)
309 *offset = addr - bestval; 309 *offset = addr - bestval;
310 310
311 return kallsyms_symbol_name(kallsyms, 311 return kallsyms_symbol_name(kallsyms, best);
312 } 312 }
313 313
314 void * __weak dereference_module_function_desc 314 void * __weak dereference_module_function_descriptor(struct module *mod,
315 315 void *ptr)
316 { 316 {
317 return ptr; 317 return ptr;
318 } 318 }
319 319
320 /* 320 /*
321 * For kallsyms to ask for address resolution. 321 * For kallsyms to ask for address resolution. NULL means not found. Careful
322 * not to lock to avoid deadlock on oopses, si 322 * not to lock to avoid deadlock on oopses, simply disable preemption.
323 */ 323 */
324 int module_address_lookup(unsigned long addr, 324 int module_address_lookup(unsigned long addr,
325 unsigned long *size, 325 unsigned long *size,
326 unsigned long *offse 326 unsigned long *offset,
327 char **modname, 327 char **modname,
328 const unsigned char 328 const unsigned char **modbuildid,
329 char *namebuf) 329 char *namebuf)
330 { 330 {
331 const char *sym; 331 const char *sym;
332 int ret = 0; 332 int ret = 0;
333 struct module *mod; 333 struct module *mod;
334 334
335 preempt_disable(); 335 preempt_disable();
336 mod = __module_address(addr); 336 mod = __module_address(addr);
337 if (mod) { 337 if (mod) {
338 if (modname) 338 if (modname)
339 *modname = mod->name; 339 *modname = mod->name;
340 if (modbuildid) { 340 if (modbuildid) {
341 #if IS_ENABLED(CONFIG_STACKTRACE_BUILD_ID) 341 #if IS_ENABLED(CONFIG_STACKTRACE_BUILD_ID)
342 *modbuildid = mod->bui 342 *modbuildid = mod->build_id;
343 #else 343 #else
344 *modbuildid = NULL; 344 *modbuildid = NULL;
345 #endif 345 #endif
346 } 346 }
347 347
348 sym = find_kallsyms_symbol(mod 348 sym = find_kallsyms_symbol(mod, addr, size, offset);
349 349
350 if (sym) 350 if (sym)
351 ret = strscpy(namebuf, 351 ret = strscpy(namebuf, sym, KSYM_NAME_LEN);
352 } 352 }
353 preempt_enable(); 353 preempt_enable();
354 354
355 return ret; 355 return ret;
356 } 356 }
357 357
358 int lookup_module_symbol_name(unsigned long ad 358 int lookup_module_symbol_name(unsigned long addr, char *symname)
359 { 359 {
360 struct module *mod; 360 struct module *mod;
361 361
362 preempt_disable(); 362 preempt_disable();
363 list_for_each_entry_rcu(mod, &modules, 363 list_for_each_entry_rcu(mod, &modules, list) {
364 if (mod->state == MODULE_STATE 364 if (mod->state == MODULE_STATE_UNFORMED)
365 continue; 365 continue;
366 if (within_module(addr, mod)) 366 if (within_module(addr, mod)) {
367 const char *sym; 367 const char *sym;
368 368
369 sym = find_kallsyms_sy 369 sym = find_kallsyms_symbol(mod, addr, NULL, NULL);
370 if (!sym) 370 if (!sym)
371 goto out; 371 goto out;
372 372
373 strscpy(symname, sym, 373 strscpy(symname, sym, KSYM_NAME_LEN);
374 preempt_enable(); 374 preempt_enable();
375 return 0; 375 return 0;
376 } 376 }
377 } 377 }
378 out: 378 out:
379 preempt_enable(); 379 preempt_enable();
380 return -ERANGE; 380 return -ERANGE;
381 } 381 }
382 382
383 int module_get_kallsym(unsigned int symnum, un 383 int module_get_kallsym(unsigned int symnum, unsigned long *value, char *type,
384 char *name, char *modul 384 char *name, char *module_name, int *exported)
385 { 385 {
386 struct module *mod; 386 struct module *mod;
387 387
388 preempt_disable(); 388 preempt_disable();
389 list_for_each_entry_rcu(mod, &modules, 389 list_for_each_entry_rcu(mod, &modules, list) {
390 struct mod_kallsyms *kallsyms; 390 struct mod_kallsyms *kallsyms;
391 391
392 if (mod->state == MODULE_STATE 392 if (mod->state == MODULE_STATE_UNFORMED)
393 continue; 393 continue;
394 kallsyms = rcu_dereference_sch 394 kallsyms = rcu_dereference_sched(mod->kallsyms);
395 if (symnum < kallsyms->num_sym 395 if (symnum < kallsyms->num_symtab) {
396 const Elf_Sym *sym = & 396 const Elf_Sym *sym = &kallsyms->symtab[symnum];
397 397
398 *value = kallsyms_symb 398 *value = kallsyms_symbol_value(sym);
399 *type = kallsyms->type 399 *type = kallsyms->typetab[symnum];
400 strscpy(name, kallsyms 400 strscpy(name, kallsyms_symbol_name(kallsyms, symnum), KSYM_NAME_LEN);
401 strscpy(module_name, m 401 strscpy(module_name, mod->name, MODULE_NAME_LEN);
402 *exported = is_exporte 402 *exported = is_exported(name, *value, mod);
403 preempt_enable(); 403 preempt_enable();
404 return 0; 404 return 0;
405 } 405 }
406 symnum -= kallsyms->num_symtab 406 symnum -= kallsyms->num_symtab;
407 } 407 }
408 preempt_enable(); 408 preempt_enable();
409 return -ERANGE; 409 return -ERANGE;
410 } 410 }
411 411
412 /* Given a module and name of symbol, find and 412 /* Given a module and name of symbol, find and return the symbol's value */
413 static unsigned long __find_kallsyms_symbol_va 413 static unsigned long __find_kallsyms_symbol_value(struct module *mod, const char *name)
414 { 414 {
415 unsigned int i; 415 unsigned int i;
416 struct mod_kallsyms *kallsyms = rcu_de 416 struct mod_kallsyms *kallsyms = rcu_dereference_sched(mod->kallsyms);
417 417
418 for (i = 0; i < kallsyms->num_symtab; 418 for (i = 0; i < kallsyms->num_symtab; i++) {
419 const Elf_Sym *sym = &kallsyms 419 const Elf_Sym *sym = &kallsyms->symtab[i];
420 420
421 if (strcmp(name, kallsyms_symb 421 if (strcmp(name, kallsyms_symbol_name(kallsyms, i)) == 0 &&
422 sym->st_shndx != SHN_UNDEF 422 sym->st_shndx != SHN_UNDEF)
423 return kallsyms_symbol 423 return kallsyms_symbol_value(sym);
424 } 424 }
425 return 0; 425 return 0;
426 } 426 }
427 427
428 static unsigned long __module_kallsyms_lookup_ 428 static unsigned long __module_kallsyms_lookup_name(const char *name)
429 { 429 {
430 struct module *mod; 430 struct module *mod;
431 char *colon; 431 char *colon;
432 432
433 colon = strnchr(name, MODULE_NAME_LEN, 433 colon = strnchr(name, MODULE_NAME_LEN, ':');
434 if (colon) { 434 if (colon) {
435 mod = find_module_all(name, co 435 mod = find_module_all(name, colon - name, false);
436 if (mod) 436 if (mod)
437 return __find_kallsyms 437 return __find_kallsyms_symbol_value(mod, colon + 1);
438 return 0; 438 return 0;
439 } 439 }
440 440
441 list_for_each_entry_rcu(mod, &modules, 441 list_for_each_entry_rcu(mod, &modules, list) {
442 unsigned long ret; 442 unsigned long ret;
443 443
444 if (mod->state == MODULE_STATE 444 if (mod->state == MODULE_STATE_UNFORMED)
445 continue; 445 continue;
446 ret = __find_kallsyms_symbol_v 446 ret = __find_kallsyms_symbol_value(mod, name);
447 if (ret) 447 if (ret)
448 return ret; 448 return ret;
449 } 449 }
450 return 0; 450 return 0;
451 } 451 }
452 452
453 /* Look for this name: can be of form module:n 453 /* Look for this name: can be of form module:name. */
454 unsigned long module_kallsyms_lookup_name(cons 454 unsigned long module_kallsyms_lookup_name(const char *name)
455 { 455 {
456 unsigned long ret; 456 unsigned long ret;
457 457
458 /* Don't lock: we're in enough trouble 458 /* Don't lock: we're in enough trouble already. */
459 preempt_disable(); 459 preempt_disable();
460 ret = __module_kallsyms_lookup_name(na 460 ret = __module_kallsyms_lookup_name(name);
461 preempt_enable(); 461 preempt_enable();
462 return ret; 462 return ret;
463 } 463 }
464 464
465 unsigned long find_kallsyms_symbol_value(struc 465 unsigned long find_kallsyms_symbol_value(struct module *mod, const char *name)
466 { 466 {
467 unsigned long ret; 467 unsigned long ret;
468 468
469 preempt_disable(); 469 preempt_disable();
470 ret = __find_kallsyms_symbol_value(mod 470 ret = __find_kallsyms_symbol_value(mod, name);
471 preempt_enable(); 471 preempt_enable();
472 return ret; 472 return ret;
473 } 473 }
474 474
475 int module_kallsyms_on_each_symbol(const char 475 int module_kallsyms_on_each_symbol(const char *modname,
476 int (*fn)(v 476 int (*fn)(void *, const char *, unsigned long),
477 void *data) 477 void *data)
478 { 478 {
479 struct module *mod; 479 struct module *mod;
480 unsigned int i; 480 unsigned int i;
481 int ret = 0; 481 int ret = 0;
482 482
483 mutex_lock(&module_mutex); 483 mutex_lock(&module_mutex);
484 list_for_each_entry(mod, &modules, lis 484 list_for_each_entry(mod, &modules, list) {
485 struct mod_kallsyms *kallsyms; 485 struct mod_kallsyms *kallsyms;
486 486
487 if (mod->state == MODULE_STATE 487 if (mod->state == MODULE_STATE_UNFORMED)
488 continue; 488 continue;
489 489
490 if (modname && strcmp(modname, 490 if (modname && strcmp(modname, mod->name))
491 continue; 491 continue;
492 492
493 /* Use rcu_dereference_sched() 493 /* Use rcu_dereference_sched() to remain compliant with the sparse tool */
494 preempt_disable(); 494 preempt_disable();
495 kallsyms = rcu_dereference_sch 495 kallsyms = rcu_dereference_sched(mod->kallsyms);
496 preempt_enable(); 496 preempt_enable();
497 497
498 for (i = 0; i < kallsyms->num_ 498 for (i = 0; i < kallsyms->num_symtab; i++) {
499 const Elf_Sym *sym = & 499 const Elf_Sym *sym = &kallsyms->symtab[i];
500 500
501 if (sym->st_shndx == S 501 if (sym->st_shndx == SHN_UNDEF)
502 continue; 502 continue;
503 503
504 ret = fn(data, kallsym 504 ret = fn(data, kallsyms_symbol_name(kallsyms, i),
505 kallsyms_symb 505 kallsyms_symbol_value(sym));
506 if (ret != 0) 506 if (ret != 0)
507 goto out; 507 goto out;
508 } 508 }
509 509
510 /* 510 /*
511 * The given module is found, 511 * The given module is found, the subsequent modules do not
512 * need to be compared. 512 * need to be compared.
513 */ 513 */
514 if (modname) 514 if (modname)
515 break; 515 break;
516 } 516 }
517 out: 517 out:
518 mutex_unlock(&module_mutex); 518 mutex_unlock(&module_mutex);
519 return ret; 519 return ret;
520 } 520 }
521 521
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