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4552d5dc JB |
1 | /* |
2 | * Copyright (C) 2002-2006 Novell, Inc. | |
3 | * Jan Beulich <jbeulich@novell.com> | |
4 | * This code is released under version 2 of the GNU GPL. | |
5 | * | |
6 | * A simple API for unwinding kernel stacks. This is used for | |
7 | * debugging and error reporting purposes. The kernel doesn't need | |
8 | * full-blown stack unwinding with all the bells and whistles, so there | |
9 | * is not much point in implementing the full Dwarf2 unwind API. | |
10 | */ | |
11 | ||
12 | #include <linux/unwind.h> | |
13 | #include <linux/module.h> | |
690a973f JB |
14 | #include <linux/bootmem.h> |
15 | #include <linux/sort.h> | |
4552d5dc | 16 | #include <linux/stop_machine.h> |
e2124bb8 | 17 | #include <linux/uaccess.h> |
4552d5dc JB |
18 | #include <asm/sections.h> |
19 | #include <asm/uaccess.h> | |
20 | #include <asm/unaligned.h> | |
21 | ||
b65780e1 | 22 | extern const char __start_unwind[], __end_unwind[]; |
690a973f | 23 | extern const u8 __start_unwind_hdr[], __end_unwind_hdr[]; |
4552d5dc JB |
24 | |
25 | #define MAX_STACK_DEPTH 8 | |
26 | ||
27 | #define EXTRA_INFO(f) { \ | |
28 | BUILD_BUG_ON_ZERO(offsetof(struct unwind_frame_info, f) \ | |
29 | % FIELD_SIZEOF(struct unwind_frame_info, f)) \ | |
30 | + offsetof(struct unwind_frame_info, f) \ | |
31 | / FIELD_SIZEOF(struct unwind_frame_info, f), \ | |
32 | FIELD_SIZEOF(struct unwind_frame_info, f) \ | |
33 | } | |
34 | #define PTREGS_INFO(f) EXTRA_INFO(regs.f) | |
35 | ||
36 | static const struct { | |
37 | unsigned offs:BITS_PER_LONG / 2; | |
38 | unsigned width:BITS_PER_LONG / 2; | |
39 | } reg_info[] = { | |
40 | UNW_REGISTER_INFO | |
41 | }; | |
42 | ||
43 | #undef PTREGS_INFO | |
44 | #undef EXTRA_INFO | |
45 | ||
46 | #ifndef REG_INVALID | |
47 | #define REG_INVALID(r) (reg_info[r].width == 0) | |
48 | #endif | |
49 | ||
50 | #define DW_CFA_nop 0x00 | |
51 | #define DW_CFA_set_loc 0x01 | |
52 | #define DW_CFA_advance_loc1 0x02 | |
53 | #define DW_CFA_advance_loc2 0x03 | |
54 | #define DW_CFA_advance_loc4 0x04 | |
55 | #define DW_CFA_offset_extended 0x05 | |
56 | #define DW_CFA_restore_extended 0x06 | |
57 | #define DW_CFA_undefined 0x07 | |
58 | #define DW_CFA_same_value 0x08 | |
59 | #define DW_CFA_register 0x09 | |
60 | #define DW_CFA_remember_state 0x0a | |
61 | #define DW_CFA_restore_state 0x0b | |
62 | #define DW_CFA_def_cfa 0x0c | |
63 | #define DW_CFA_def_cfa_register 0x0d | |
64 | #define DW_CFA_def_cfa_offset 0x0e | |
65 | #define DW_CFA_def_cfa_expression 0x0f | |
66 | #define DW_CFA_expression 0x10 | |
67 | #define DW_CFA_offset_extended_sf 0x11 | |
68 | #define DW_CFA_def_cfa_sf 0x12 | |
69 | #define DW_CFA_def_cfa_offset_sf 0x13 | |
70 | #define DW_CFA_val_offset 0x14 | |
71 | #define DW_CFA_val_offset_sf 0x15 | |
72 | #define DW_CFA_val_expression 0x16 | |
73 | #define DW_CFA_lo_user 0x1c | |
74 | #define DW_CFA_GNU_window_save 0x2d | |
75 | #define DW_CFA_GNU_args_size 0x2e | |
76 | #define DW_CFA_GNU_negative_offset_extended 0x2f | |
77 | #define DW_CFA_hi_user 0x3f | |
78 | ||
79 | #define DW_EH_PE_FORM 0x07 | |
80 | #define DW_EH_PE_native 0x00 | |
81 | #define DW_EH_PE_leb128 0x01 | |
82 | #define DW_EH_PE_data2 0x02 | |
83 | #define DW_EH_PE_data4 0x03 | |
84 | #define DW_EH_PE_data8 0x04 | |
85 | #define DW_EH_PE_signed 0x08 | |
86 | #define DW_EH_PE_ADJUST 0x70 | |
87 | #define DW_EH_PE_abs 0x00 | |
88 | #define DW_EH_PE_pcrel 0x10 | |
89 | #define DW_EH_PE_textrel 0x20 | |
90 | #define DW_EH_PE_datarel 0x30 | |
91 | #define DW_EH_PE_funcrel 0x40 | |
92 | #define DW_EH_PE_aligned 0x50 | |
93 | #define DW_EH_PE_indirect 0x80 | |
94 | #define DW_EH_PE_omit 0xff | |
95 | ||
96 | typedef unsigned long uleb128_t; | |
97 | typedef signed long sleb128_t; | |
359ad0d4 | 98 | #define sleb128abs __builtin_labs |
4552d5dc JB |
99 | |
100 | static struct unwind_table { | |
101 | struct { | |
102 | unsigned long pc; | |
103 | unsigned long range; | |
104 | } core, init; | |
105 | const void *address; | |
106 | unsigned long size; | |
690a973f JB |
107 | const unsigned char *header; |
108 | unsigned long hdrsz; | |
4552d5dc JB |
109 | struct unwind_table *link; |
110 | const char *name; | |
e6cab99b | 111 | } root_table; |
4552d5dc JB |
112 | |
113 | struct unwind_item { | |
114 | enum item_location { | |
115 | Nowhere, | |
116 | Memory, | |
117 | Register, | |
118 | Value | |
119 | } where; | |
120 | uleb128_t value; | |
121 | }; | |
122 | ||
123 | struct unwind_state { | |
124 | uleb128_t loc, org; | |
125 | const u8 *cieStart, *cieEnd; | |
126 | uleb128_t codeAlign; | |
127 | sleb128_t dataAlign; | |
128 | struct cfa { | |
129 | uleb128_t reg, offs; | |
130 | } cfa; | |
131 | struct unwind_item regs[ARRAY_SIZE(reg_info)]; | |
132 | unsigned stackDepth:8; | |
133 | unsigned version:8; | |
134 | const u8 *label; | |
135 | const u8 *stack[MAX_STACK_DEPTH]; | |
136 | }; | |
137 | ||
138 | static const struct cfa badCFA = { ARRAY_SIZE(reg_info), 1 }; | |
139 | ||
6d0185ea JB |
140 | static unsigned unwind_debug; |
141 | static int __init unwind_debug_setup(char *s) | |
142 | { | |
143 | unwind_debug = simple_strtoul(s, NULL, 0); | |
144 | return 1; | |
145 | } | |
146 | __setup("unwind_debug=", unwind_debug_setup); | |
147 | #define dprintk(lvl, fmt, args...) \ | |
148 | ((void)(lvl > unwind_debug \ | |
149 | || printk(KERN_DEBUG "unwind: " fmt "\n", ##args))) | |
150 | ||
4552d5dc JB |
151 | static struct unwind_table *find_table(unsigned long pc) |
152 | { | |
153 | struct unwind_table *table; | |
154 | ||
155 | for (table = &root_table; table; table = table->link) | |
156 | if ((pc >= table->core.pc | |
157 | && pc < table->core.pc + table->core.range) | |
158 | || (pc >= table->init.pc | |
159 | && pc < table->init.pc + table->init.range)) | |
160 | break; | |
161 | ||
162 | return table; | |
163 | } | |
164 | ||
690a973f JB |
165 | static unsigned long read_pointer(const u8 **pLoc, |
166 | const void *end, | |
c65f38d9 JB |
167 | signed ptrType, |
168 | unsigned long text_base, | |
169 | unsigned long data_base); | |
690a973f | 170 | |
4552d5dc JB |
171 | static void init_unwind_table(struct unwind_table *table, |
172 | const char *name, | |
173 | const void *core_start, | |
174 | unsigned long core_size, | |
175 | const void *init_start, | |
176 | unsigned long init_size, | |
177 | const void *table_start, | |
690a973f JB |
178 | unsigned long table_size, |
179 | const u8 *header_start, | |
180 | unsigned long header_size) | |
4552d5dc | 181 | { |
690a973f JB |
182 | const u8 *ptr = header_start + 4; |
183 | const u8 *end = header_start + header_size; | |
184 | ||
4552d5dc JB |
185 | table->core.pc = (unsigned long)core_start; |
186 | table->core.range = core_size; | |
187 | table->init.pc = (unsigned long)init_start; | |
188 | table->init.range = init_size; | |
189 | table->address = table_start; | |
190 | table->size = table_size; | |
690a973f JB |
191 | /* See if the linker provided table looks valid. */ |
192 | if (header_size <= 4 | |
193 | || header_start[0] != 1 | |
c65f38d9 JB |
194 | || (void *)read_pointer(&ptr, end, header_start[1], 0, 0) |
195 | != table_start | |
196 | || !read_pointer(&ptr, end, header_start[2], 0, 0) | |
197 | || !read_pointer(&ptr, end, header_start[3], 0, | |
198 | (unsigned long)header_start) | |
199 | || !read_pointer(&ptr, end, header_start[3], 0, | |
200 | (unsigned long)header_start)) | |
690a973f JB |
201 | header_start = NULL; |
202 | table->hdrsz = header_size; | |
203 | smp_wmb(); | |
204 | table->header = header_start; | |
4552d5dc JB |
205 | table->link = NULL; |
206 | table->name = name; | |
207 | } | |
208 | ||
209 | void __init unwind_init(void) | |
210 | { | |
211 | init_unwind_table(&root_table, "kernel", | |
212 | _text, _end - _text, | |
213 | NULL, 0, | |
690a973f JB |
214 | __start_unwind, __end_unwind - __start_unwind, |
215 | __start_unwind_hdr, __end_unwind_hdr - __start_unwind_hdr); | |
216 | } | |
217 | ||
218 | static const u32 bad_cie, not_fde; | |
219 | static const u32 *cie_for_fde(const u32 *fde, const struct unwind_table *); | |
220 | static signed fde_pointer_type(const u32 *cie); | |
221 | ||
222 | struct eh_frame_hdr_table_entry { | |
223 | unsigned long start, fde; | |
224 | }; | |
225 | ||
226 | static int cmp_eh_frame_hdr_table_entries(const void *p1, const void *p2) | |
227 | { | |
228 | const struct eh_frame_hdr_table_entry *e1 = p1; | |
229 | const struct eh_frame_hdr_table_entry *e2 = p2; | |
230 | ||
231 | return (e1->start > e2->start) - (e1->start < e2->start); | |
232 | } | |
233 | ||
234 | static void swap_eh_frame_hdr_table_entries(void *p1, void *p2, int size) | |
235 | { | |
236 | struct eh_frame_hdr_table_entry *e1 = p1; | |
237 | struct eh_frame_hdr_table_entry *e2 = p2; | |
238 | unsigned long v; | |
239 | ||
240 | v = e1->start; | |
241 | e1->start = e2->start; | |
242 | e2->start = v; | |
243 | v = e1->fde; | |
244 | e1->fde = e2->fde; | |
245 | e2->fde = v; | |
246 | } | |
247 | ||
248 | static void __init setup_unwind_table(struct unwind_table *table, | |
249 | void *(*alloc)(unsigned long)) | |
250 | { | |
251 | const u8 *ptr; | |
252 | unsigned long tableSize = table->size, hdrSize; | |
253 | unsigned n; | |
254 | const u32 *fde; | |
255 | struct { | |
256 | u8 version; | |
257 | u8 eh_frame_ptr_enc; | |
258 | u8 fde_count_enc; | |
259 | u8 table_enc; | |
260 | unsigned long eh_frame_ptr; | |
261 | unsigned int fde_count; | |
262 | struct eh_frame_hdr_table_entry table[]; | |
263 | } __attribute__((__packed__)) *header; | |
264 | ||
265 | if (table->header) | |
266 | return; | |
267 | ||
268 | if (table->hdrsz) | |
269 | printk(KERN_WARNING ".eh_frame_hdr for '%s' present but unusable\n", | |
270 | table->name); | |
271 | ||
272 | if (tableSize & (sizeof(*fde) - 1)) | |
273 | return; | |
274 | ||
275 | for (fde = table->address, n = 0; | |
276 | tableSize > sizeof(*fde) && tableSize - sizeof(*fde) >= *fde; | |
277 | tableSize -= sizeof(*fde) + *fde, fde += 1 + *fde / sizeof(*fde)) { | |
278 | const u32 *cie = cie_for_fde(fde, table); | |
279 | signed ptrType; | |
280 | ||
281 | if (cie == ¬_fde) | |
282 | continue; | |
283 | if (cie == NULL | |
284 | || cie == &bad_cie | |
285 | || (ptrType = fde_pointer_type(cie)) < 0) | |
286 | return; | |
287 | ptr = (const u8 *)(fde + 2); | |
288 | if (!read_pointer(&ptr, | |
289 | (const u8 *)(fde + 1) + *fde, | |
c65f38d9 | 290 | ptrType, 0, 0)) |
690a973f JB |
291 | return; |
292 | ++n; | |
293 | } | |
294 | ||
295 | if (tableSize || !n) | |
296 | return; | |
297 | ||
298 | hdrSize = 4 + sizeof(unsigned long) + sizeof(unsigned int) | |
299 | + 2 * n * sizeof(unsigned long); | |
6d0185ea | 300 | dprintk(2, "Binary lookup table size for %s: %lu bytes", table->name, hdrSize); |
690a973f JB |
301 | header = alloc(hdrSize); |
302 | if (!header) | |
303 | return; | |
304 | header->version = 1; | |
305 | header->eh_frame_ptr_enc = DW_EH_PE_abs|DW_EH_PE_native; | |
306 | header->fde_count_enc = DW_EH_PE_abs|DW_EH_PE_data4; | |
307 | header->table_enc = DW_EH_PE_abs|DW_EH_PE_native; | |
308 | put_unaligned((unsigned long)table->address, &header->eh_frame_ptr); | |
309 | BUILD_BUG_ON(offsetof(typeof(*header), fde_count) | |
310 | % __alignof(typeof(header->fde_count))); | |
311 | header->fde_count = n; | |
312 | ||
313 | BUILD_BUG_ON(offsetof(typeof(*header), table) | |
314 | % __alignof(typeof(*header->table))); | |
315 | for (fde = table->address, tableSize = table->size, n = 0; | |
316 | tableSize; | |
317 | tableSize -= sizeof(*fde) + *fde, fde += 1 + *fde / sizeof(*fde)) { | |
318 | const u32 *cie = fde + 1 - fde[1] / sizeof(*fde); | |
319 | ||
320 | if (!fde[1]) | |
321 | continue; /* this is a CIE */ | |
322 | ptr = (const u8 *)(fde + 2); | |
323 | header->table[n].start = read_pointer(&ptr, | |
324 | (const u8 *)(fde + 1) + *fde, | |
c65f38d9 | 325 | fde_pointer_type(cie), 0, 0); |
690a973f JB |
326 | header->table[n].fde = (unsigned long)fde; |
327 | ++n; | |
328 | } | |
329 | WARN_ON(n != header->fde_count); | |
330 | ||
331 | sort(header->table, | |
332 | n, | |
333 | sizeof(*header->table), | |
334 | cmp_eh_frame_hdr_table_entries, | |
335 | swap_eh_frame_hdr_table_entries); | |
336 | ||
337 | table->hdrsz = hdrSize; | |
338 | smp_wmb(); | |
339 | table->header = (const void *)header; | |
340 | } | |
341 | ||
342 | static void *__init balloc(unsigned long sz) | |
343 | { | |
344 | return __alloc_bootmem_nopanic(sz, | |
345 | sizeof(unsigned int), | |
346 | __pa(MAX_DMA_ADDRESS)); | |
347 | } | |
348 | ||
349 | void __init unwind_setup(void) | |
350 | { | |
351 | setup_unwind_table(&root_table, balloc); | |
4552d5dc JB |
352 | } |
353 | ||
83f4fcce JB |
354 | #ifdef CONFIG_MODULES |
355 | ||
e6cab99b CE |
356 | static struct unwind_table *last_table; |
357 | ||
4552d5dc JB |
358 | /* Must be called with module_mutex held. */ |
359 | void *unwind_add_table(struct module *module, | |
360 | const void *table_start, | |
361 | unsigned long table_size) | |
362 | { | |
363 | struct unwind_table *table; | |
364 | ||
365 | if (table_size <= 0) | |
366 | return NULL; | |
367 | ||
368 | table = kmalloc(sizeof(*table), GFP_KERNEL); | |
369 | if (!table) | |
370 | return NULL; | |
371 | ||
372 | init_unwind_table(table, module->name, | |
373 | module->module_core, module->core_size, | |
374 | module->module_init, module->init_size, | |
690a973f JB |
375 | table_start, table_size, |
376 | NULL, 0); | |
4552d5dc JB |
377 | |
378 | if (last_table) | |
379 | last_table->link = table; | |
380 | else | |
381 | root_table.link = table; | |
382 | last_table = table; | |
383 | ||
384 | return table; | |
385 | } | |
386 | ||
387 | struct unlink_table_info | |
388 | { | |
389 | struct unwind_table *table; | |
390 | int init_only; | |
391 | }; | |
392 | ||
393 | static int unlink_table(void *arg) | |
394 | { | |
395 | struct unlink_table_info *info = arg; | |
396 | struct unwind_table *table = info->table, *prev; | |
397 | ||
398 | for (prev = &root_table; prev->link && prev->link != table; prev = prev->link) | |
399 | ; | |
400 | ||
401 | if (prev->link) { | |
402 | if (info->init_only) { | |
403 | table->init.pc = 0; | |
404 | table->init.range = 0; | |
405 | info->table = NULL; | |
406 | } else { | |
407 | prev->link = table->link; | |
408 | if (!prev->link) | |
409 | last_table = prev; | |
410 | } | |
411 | } else | |
412 | info->table = NULL; | |
413 | ||
414 | return 0; | |
415 | } | |
416 | ||
417 | /* Must be called with module_mutex held. */ | |
418 | void unwind_remove_table(void *handle, int init_only) | |
419 | { | |
420 | struct unwind_table *table = handle; | |
421 | struct unlink_table_info info; | |
422 | ||
423 | if (!table || table == &root_table) | |
424 | return; | |
425 | ||
426 | if (init_only && table == last_table) { | |
427 | table->init.pc = 0; | |
428 | table->init.range = 0; | |
429 | return; | |
430 | } | |
431 | ||
432 | info.table = table; | |
433 | info.init_only = init_only; | |
434 | stop_machine_run(unlink_table, &info, NR_CPUS); | |
435 | ||
436 | if (info.table) | |
437 | kfree(table); | |
438 | } | |
439 | ||
83f4fcce JB |
440 | #endif /* CONFIG_MODULES */ |
441 | ||
4552d5dc JB |
442 | static uleb128_t get_uleb128(const u8 **pcur, const u8 *end) |
443 | { | |
444 | const u8 *cur = *pcur; | |
445 | uleb128_t value; | |
446 | unsigned shift; | |
447 | ||
448 | for (shift = 0, value = 0; cur < end; shift += 7) { | |
449 | if (shift + 7 > 8 * sizeof(value) | |
450 | && (*cur & 0x7fU) >= (1U << (8 * sizeof(value) - shift))) { | |
451 | cur = end + 1; | |
452 | break; | |
453 | } | |
454 | value |= (uleb128_t)(*cur & 0x7f) << shift; | |
455 | if (!(*cur++ & 0x80)) | |
456 | break; | |
457 | } | |
458 | *pcur = cur; | |
459 | ||
460 | return value; | |
461 | } | |
462 | ||
463 | static sleb128_t get_sleb128(const u8 **pcur, const u8 *end) | |
464 | { | |
465 | const u8 *cur = *pcur; | |
466 | sleb128_t value; | |
467 | unsigned shift; | |
468 | ||
469 | for (shift = 0, value = 0; cur < end; shift += 7) { | |
470 | if (shift + 7 > 8 * sizeof(value) | |
471 | && (*cur & 0x7fU) >= (1U << (8 * sizeof(value) - shift))) { | |
472 | cur = end + 1; | |
473 | break; | |
474 | } | |
475 | value |= (sleb128_t)(*cur & 0x7f) << shift; | |
476 | if (!(*cur & 0x80)) { | |
477 | value |= -(*cur++ & 0x40) << shift; | |
478 | break; | |
479 | } | |
480 | } | |
481 | *pcur = cur; | |
482 | ||
483 | return value; | |
484 | } | |
485 | ||
690a973f JB |
486 | static const u32 *cie_for_fde(const u32 *fde, const struct unwind_table *table) |
487 | { | |
488 | const u32 *cie; | |
489 | ||
490 | if (!*fde || (*fde & (sizeof(*fde) - 1))) | |
491 | return &bad_cie; | |
492 | if (!fde[1]) | |
493 | return ¬_fde; /* this is a CIE */ | |
494 | if ((fde[1] & (sizeof(*fde) - 1)) | |
495 | || fde[1] > (unsigned long)(fde + 1) - (unsigned long)table->address) | |
496 | return NULL; /* this is not a valid FDE */ | |
497 | cie = fde + 1 - fde[1] / sizeof(*fde); | |
498 | if (*cie <= sizeof(*cie) + 4 | |
499 | || *cie >= fde[1] - sizeof(*fde) | |
500 | || (*cie & (sizeof(*cie) - 1)) | |
501 | || cie[1]) | |
502 | return NULL; /* this is not a (valid) CIE */ | |
503 | return cie; | |
504 | } | |
505 | ||
4552d5dc JB |
506 | static unsigned long read_pointer(const u8 **pLoc, |
507 | const void *end, | |
c65f38d9 JB |
508 | signed ptrType, |
509 | unsigned long text_base, | |
510 | unsigned long data_base) | |
4552d5dc JB |
511 | { |
512 | unsigned long value = 0; | |
513 | union { | |
514 | const u8 *p8; | |
515 | const u16 *p16u; | |
516 | const s16 *p16s; | |
517 | const u32 *p32u; | |
518 | const s32 *p32s; | |
519 | const unsigned long *pul; | |
520 | } ptr; | |
521 | ||
6d0185ea JB |
522 | if (ptrType < 0 || ptrType == DW_EH_PE_omit) { |
523 | dprintk(1, "Invalid pointer encoding %02X (%p,%p).", ptrType, *pLoc, end); | |
4552d5dc | 524 | return 0; |
6d0185ea | 525 | } |
4552d5dc JB |
526 | ptr.p8 = *pLoc; |
527 | switch(ptrType & DW_EH_PE_FORM) { | |
528 | case DW_EH_PE_data2: | |
6d0185ea JB |
529 | if (end < (const void *)(ptr.p16u + 1)) { |
530 | dprintk(1, "Data16 overrun (%p,%p).", ptr.p8, end); | |
4552d5dc | 531 | return 0; |
6d0185ea | 532 | } |
4552d5dc JB |
533 | if(ptrType & DW_EH_PE_signed) |
534 | value = get_unaligned(ptr.p16s++); | |
535 | else | |
536 | value = get_unaligned(ptr.p16u++); | |
537 | break; | |
538 | case DW_EH_PE_data4: | |
539 | #ifdef CONFIG_64BIT | |
6d0185ea JB |
540 | if (end < (const void *)(ptr.p32u + 1)) { |
541 | dprintk(1, "Data32 overrun (%p,%p).", ptr.p8, end); | |
4552d5dc | 542 | return 0; |
6d0185ea | 543 | } |
4552d5dc JB |
544 | if(ptrType & DW_EH_PE_signed) |
545 | value = get_unaligned(ptr.p32s++); | |
546 | else | |
547 | value = get_unaligned(ptr.p32u++); | |
548 | break; | |
549 | case DW_EH_PE_data8: | |
550 | BUILD_BUG_ON(sizeof(u64) != sizeof(value)); | |
551 | #else | |
552 | BUILD_BUG_ON(sizeof(u32) != sizeof(value)); | |
553 | #endif | |
554 | case DW_EH_PE_native: | |
6d0185ea JB |
555 | if (end < (const void *)(ptr.pul + 1)) { |
556 | dprintk(1, "DataUL overrun (%p,%p).", ptr.p8, end); | |
4552d5dc | 557 | return 0; |
6d0185ea | 558 | } |
4552d5dc JB |
559 | value = get_unaligned(ptr.pul++); |
560 | break; | |
561 | case DW_EH_PE_leb128: | |
562 | BUILD_BUG_ON(sizeof(uleb128_t) > sizeof(value)); | |
563 | value = ptrType & DW_EH_PE_signed | |
564 | ? get_sleb128(&ptr.p8, end) | |
565 | : get_uleb128(&ptr.p8, end); | |
6d0185ea JB |
566 | if ((const void *)ptr.p8 > end) { |
567 | dprintk(1, "DataLEB overrun (%p,%p).", ptr.p8, end); | |
4552d5dc | 568 | return 0; |
6d0185ea | 569 | } |
4552d5dc JB |
570 | break; |
571 | default: | |
6d0185ea JB |
572 | dprintk(2, "Cannot decode pointer type %02X (%p,%p).", |
573 | ptrType, ptr.p8, end); | |
4552d5dc JB |
574 | return 0; |
575 | } | |
576 | switch(ptrType & DW_EH_PE_ADJUST) { | |
577 | case DW_EH_PE_abs: | |
578 | break; | |
579 | case DW_EH_PE_pcrel: | |
580 | value += (unsigned long)*pLoc; | |
581 | break; | |
c65f38d9 JB |
582 | case DW_EH_PE_textrel: |
583 | if (likely(text_base)) { | |
584 | value += text_base; | |
585 | break; | |
586 | } | |
587 | dprintk(2, "Text-relative encoding %02X (%p,%p), but zero text base.", | |
588 | ptrType, *pLoc, end); | |
589 | return 0; | |
590 | case DW_EH_PE_datarel: | |
591 | if (likely(data_base)) { | |
592 | value += data_base; | |
593 | break; | |
594 | } | |
595 | dprintk(2, "Data-relative encoding %02X (%p,%p), but zero data base.", | |
596 | ptrType, *pLoc, end); | |
597 | return 0; | |
4552d5dc | 598 | default: |
6d0185ea JB |
599 | dprintk(2, "Cannot adjust pointer type %02X (%p,%p).", |
600 | ptrType, *pLoc, end); | |
4552d5dc JB |
601 | return 0; |
602 | } | |
603 | if ((ptrType & DW_EH_PE_indirect) | |
6d0185ea JB |
604 | && probe_kernel_address((unsigned long *)value, value)) { |
605 | dprintk(1, "Cannot read indirect value %lx (%p,%p).", | |
606 | value, *pLoc, end); | |
4552d5dc | 607 | return 0; |
6d0185ea | 608 | } |
4552d5dc JB |
609 | *pLoc = ptr.p8; |
610 | ||
611 | return value; | |
612 | } | |
613 | ||
614 | static signed fde_pointer_type(const u32 *cie) | |
615 | { | |
616 | const u8 *ptr = (const u8 *)(cie + 2); | |
617 | unsigned version = *ptr; | |
618 | ||
619 | if (version != 1) | |
620 | return -1; /* unsupported */ | |
621 | if (*++ptr) { | |
622 | const char *aug; | |
623 | const u8 *end = (const u8 *)(cie + 1) + *cie; | |
624 | uleb128_t len; | |
625 | ||
626 | /* check if augmentation size is first (and thus present) */ | |
627 | if (*ptr != 'z') | |
628 | return -1; | |
629 | /* check if augmentation string is nul-terminated */ | |
630 | if ((ptr = memchr(aug = (const void *)ptr, 0, end - ptr)) == NULL) | |
631 | return -1; | |
632 | ++ptr; /* skip terminator */ | |
633 | get_uleb128(&ptr, end); /* skip code alignment */ | |
634 | get_sleb128(&ptr, end); /* skip data alignment */ | |
635 | /* skip return address column */ | |
636 | version <= 1 ? (void)++ptr : (void)get_uleb128(&ptr, end); | |
637 | len = get_uleb128(&ptr, end); /* augmentation length */ | |
638 | if (ptr + len < ptr || ptr + len > end) | |
639 | return -1; | |
640 | end = ptr + len; | |
641 | while (*++aug) { | |
642 | if (ptr >= end) | |
643 | return -1; | |
644 | switch(*aug) { | |
645 | case 'L': | |
646 | ++ptr; | |
647 | break; | |
648 | case 'P': { | |
649 | signed ptrType = *ptr++; | |
650 | ||
c65f38d9 JB |
651 | if (!read_pointer(&ptr, end, ptrType, 0, 0) |
652 | || ptr > end) | |
4552d5dc JB |
653 | return -1; |
654 | } | |
655 | break; | |
656 | case 'R': | |
657 | return *ptr; | |
658 | default: | |
659 | return -1; | |
660 | } | |
661 | } | |
662 | } | |
663 | return DW_EH_PE_native|DW_EH_PE_abs; | |
664 | } | |
665 | ||
666 | static int advance_loc(unsigned long delta, struct unwind_state *state) | |
667 | { | |
668 | state->loc += delta * state->codeAlign; | |
669 | ||
670 | return delta > 0; | |
671 | } | |
672 | ||
673 | static void set_rule(uleb128_t reg, | |
674 | enum item_location where, | |
675 | uleb128_t value, | |
676 | struct unwind_state *state) | |
677 | { | |
678 | if (reg < ARRAY_SIZE(state->regs)) { | |
679 | state->regs[reg].where = where; | |
680 | state->regs[reg].value = value; | |
681 | } | |
682 | } | |
683 | ||
684 | static int processCFI(const u8 *start, | |
685 | const u8 *end, | |
686 | unsigned long targetLoc, | |
687 | signed ptrType, | |
688 | struct unwind_state *state) | |
689 | { | |
690 | union { | |
691 | const u8 *p8; | |
692 | const u16 *p16; | |
693 | const u32 *p32; | |
694 | } ptr; | |
695 | int result = 1; | |
696 | ||
697 | if (start != state->cieStart) { | |
698 | state->loc = state->org; | |
699 | result = processCFI(state->cieStart, state->cieEnd, 0, ptrType, state); | |
700 | if (targetLoc == 0 && state->label == NULL) | |
701 | return result; | |
702 | } | |
703 | for (ptr.p8 = start; result && ptr.p8 < end; ) { | |
704 | switch(*ptr.p8 >> 6) { | |
705 | uleb128_t value; | |
706 | ||
707 | case 0: | |
708 | switch(*ptr.p8++) { | |
709 | case DW_CFA_nop: | |
710 | break; | |
711 | case DW_CFA_set_loc: | |
c65f38d9 JB |
712 | state->loc = read_pointer(&ptr.p8, end, ptrType, 0, 0); |
713 | if (state->loc == 0) | |
4552d5dc JB |
714 | result = 0; |
715 | break; | |
716 | case DW_CFA_advance_loc1: | |
717 | result = ptr.p8 < end && advance_loc(*ptr.p8++, state); | |
718 | break; | |
719 | case DW_CFA_advance_loc2: | |
720 | result = ptr.p8 <= end + 2 | |
721 | && advance_loc(*ptr.p16++, state); | |
722 | break; | |
723 | case DW_CFA_advance_loc4: | |
724 | result = ptr.p8 <= end + 4 | |
725 | && advance_loc(*ptr.p32++, state); | |
726 | break; | |
727 | case DW_CFA_offset_extended: | |
728 | value = get_uleb128(&ptr.p8, end); | |
729 | set_rule(value, Memory, get_uleb128(&ptr.p8, end), state); | |
730 | break; | |
731 | case DW_CFA_val_offset: | |
732 | value = get_uleb128(&ptr.p8, end); | |
733 | set_rule(value, Value, get_uleb128(&ptr.p8, end), state); | |
734 | break; | |
735 | case DW_CFA_offset_extended_sf: | |
736 | value = get_uleb128(&ptr.p8, end); | |
737 | set_rule(value, Memory, get_sleb128(&ptr.p8, end), state); | |
738 | break; | |
739 | case DW_CFA_val_offset_sf: | |
740 | value = get_uleb128(&ptr.p8, end); | |
741 | set_rule(value, Value, get_sleb128(&ptr.p8, end), state); | |
742 | break; | |
743 | case DW_CFA_restore_extended: | |
744 | case DW_CFA_undefined: | |
745 | case DW_CFA_same_value: | |
746 | set_rule(get_uleb128(&ptr.p8, end), Nowhere, 0, state); | |
747 | break; | |
748 | case DW_CFA_register: | |
749 | value = get_uleb128(&ptr.p8, end); | |
750 | set_rule(value, | |
751 | Register, | |
752 | get_uleb128(&ptr.p8, end), state); | |
753 | break; | |
754 | case DW_CFA_remember_state: | |
755 | if (ptr.p8 == state->label) { | |
756 | state->label = NULL; | |
757 | return 1; | |
758 | } | |
6d0185ea JB |
759 | if (state->stackDepth >= MAX_STACK_DEPTH) { |
760 | dprintk(1, "State stack overflow (%p,%p).", ptr.p8, end); | |
4552d5dc | 761 | return 0; |
6d0185ea | 762 | } |
4552d5dc JB |
763 | state->stack[state->stackDepth++] = ptr.p8; |
764 | break; | |
765 | case DW_CFA_restore_state: | |
766 | if (state->stackDepth) { | |
767 | const uleb128_t loc = state->loc; | |
768 | const u8 *label = state->label; | |
769 | ||
770 | state->label = state->stack[state->stackDepth - 1]; | |
771 | memcpy(&state->cfa, &badCFA, sizeof(state->cfa)); | |
772 | memset(state->regs, 0, sizeof(state->regs)); | |
773 | state->stackDepth = 0; | |
774 | result = processCFI(start, end, 0, ptrType, state); | |
775 | state->loc = loc; | |
776 | state->label = label; | |
6d0185ea JB |
777 | } else { |
778 | dprintk(1, "State stack underflow (%p,%p).", ptr.p8, end); | |
4552d5dc | 779 | return 0; |
6d0185ea | 780 | } |
4552d5dc JB |
781 | break; |
782 | case DW_CFA_def_cfa: | |
783 | state->cfa.reg = get_uleb128(&ptr.p8, end); | |
784 | /*nobreak*/ | |
785 | case DW_CFA_def_cfa_offset: | |
786 | state->cfa.offs = get_uleb128(&ptr.p8, end); | |
787 | break; | |
788 | case DW_CFA_def_cfa_sf: | |
789 | state->cfa.reg = get_uleb128(&ptr.p8, end); | |
790 | /*nobreak*/ | |
791 | case DW_CFA_def_cfa_offset_sf: | |
792 | state->cfa.offs = get_sleb128(&ptr.p8, end) | |
793 | * state->dataAlign; | |
794 | break; | |
795 | case DW_CFA_def_cfa_register: | |
796 | state->cfa.reg = get_uleb128(&ptr.p8, end); | |
797 | break; | |
798 | /*todo case DW_CFA_def_cfa_expression: */ | |
799 | /*todo case DW_CFA_expression: */ | |
800 | /*todo case DW_CFA_val_expression: */ | |
801 | case DW_CFA_GNU_args_size: | |
802 | get_uleb128(&ptr.p8, end); | |
803 | break; | |
804 | case DW_CFA_GNU_negative_offset_extended: | |
805 | value = get_uleb128(&ptr.p8, end); | |
806 | set_rule(value, | |
807 | Memory, | |
808 | (uleb128_t)0 - get_uleb128(&ptr.p8, end), state); | |
809 | break; | |
810 | case DW_CFA_GNU_window_save: | |
811 | default: | |
6d0185ea | 812 | dprintk(1, "Unrecognized CFI op %02X (%p,%p).", ptr.p8[-1], ptr.p8 - 1, end); |
4552d5dc JB |
813 | result = 0; |
814 | break; | |
815 | } | |
816 | break; | |
817 | case 1: | |
818 | result = advance_loc(*ptr.p8++ & 0x3f, state); | |
819 | break; | |
820 | case 2: | |
821 | value = *ptr.p8++ & 0x3f; | |
822 | set_rule(value, Memory, get_uleb128(&ptr.p8, end), state); | |
823 | break; | |
824 | case 3: | |
825 | set_rule(*ptr.p8++ & 0x3f, Nowhere, 0, state); | |
826 | break; | |
827 | } | |
6d0185ea JB |
828 | if (ptr.p8 > end) { |
829 | dprintk(1, "Data overrun (%p,%p).", ptr.p8, end); | |
4552d5dc | 830 | result = 0; |
6d0185ea | 831 | } |
4552d5dc JB |
832 | if (result && targetLoc != 0 && targetLoc < state->loc) |
833 | return 1; | |
834 | } | |
835 | ||
6d0185ea JB |
836 | if (result && ptr.p8 < end) |
837 | dprintk(1, "Data underrun (%p,%p).", ptr.p8, end); | |
838 | ||
4552d5dc JB |
839 | return result |
840 | && ptr.p8 == end | |
841 | && (targetLoc == 0 | |
842 | || (/*todo While in theory this should apply, gcc in practice omits | |
843 | everything past the function prolog, and hence the location | |
844 | never reaches the end of the function. | |
845 | targetLoc < state->loc &&*/ state->label == NULL)); | |
846 | } | |
847 | ||
848 | /* Unwind to previous to frame. Returns 0 if successful, negative | |
849 | * number in case of an error. */ | |
850 | int unwind(struct unwind_frame_info *frame) | |
851 | { | |
852 | #define FRAME_REG(r, t) (((t *)frame)[reg_info[r].offs]) | |
853 | const u32 *fde = NULL, *cie = NULL; | |
854 | const u8 *ptr = NULL, *end = NULL; | |
359ad0d4 | 855 | unsigned long pc = UNW_PC(frame) - frame->call_frame, sp; |
4552d5dc JB |
856 | unsigned long startLoc = 0, endLoc = 0, cfa; |
857 | unsigned i; | |
858 | signed ptrType = -1; | |
859 | uleb128_t retAddrReg = 0; | |
690a973f | 860 | const struct unwind_table *table; |
4552d5dc JB |
861 | struct unwind_state state; |
862 | ||
863 | if (UNW_PC(frame) == 0) | |
864 | return -EINVAL; | |
adf14236 | 865 | if ((table = find_table(pc)) != NULL |
4552d5dc | 866 | && !(table->size & (sizeof(*fde) - 1))) { |
690a973f JB |
867 | const u8 *hdr = table->header; |
868 | unsigned long tableSize; | |
869 | ||
870 | smp_rmb(); | |
871 | if (hdr && hdr[0] == 1) { | |
872 | switch(hdr[3] & DW_EH_PE_FORM) { | |
873 | case DW_EH_PE_native: tableSize = sizeof(unsigned long); break; | |
874 | case DW_EH_PE_data2: tableSize = 2; break; | |
875 | case DW_EH_PE_data4: tableSize = 4; break; | |
876 | case DW_EH_PE_data8: tableSize = 8; break; | |
877 | default: tableSize = 0; break; | |
878 | } | |
879 | ptr = hdr + 4; | |
880 | end = hdr + table->hdrsz; | |
881 | if (tableSize | |
c65f38d9 | 882 | && read_pointer(&ptr, end, hdr[1], 0, 0) |
690a973f | 883 | == (unsigned long)table->address |
c65f38d9 | 884 | && (i = read_pointer(&ptr, end, hdr[2], 0, 0)) > 0 |
690a973f JB |
885 | && i == (end - ptr) / (2 * tableSize) |
886 | && !((end - ptr) % (2 * tableSize))) { | |
887 | do { | |
888 | const u8 *cur = ptr + (i / 2) * (2 * tableSize); | |
889 | ||
890 | startLoc = read_pointer(&cur, | |
891 | cur + tableSize, | |
c65f38d9 JB |
892 | hdr[3], 0, |
893 | (unsigned long)hdr); | |
690a973f JB |
894 | if (pc < startLoc) |
895 | i /= 2; | |
896 | else { | |
897 | ptr = cur - tableSize; | |
898 | i = (i + 1) / 2; | |
899 | } | |
900 | } while (startLoc && i > 1); | |
901 | if (i == 1 | |
902 | && (startLoc = read_pointer(&ptr, | |
903 | ptr + tableSize, | |
c65f38d9 JB |
904 | hdr[3], 0, |
905 | (unsigned long)hdr)) != 0 | |
690a973f JB |
906 | && pc >= startLoc) |
907 | fde = (void *)read_pointer(&ptr, | |
908 | ptr + tableSize, | |
c65f38d9 JB |
909 | hdr[3], 0, |
910 | (unsigned long)hdr); | |
4552d5dc | 911 | } |
690a973f | 912 | } |
6d0185ea JB |
913 | if(hdr && !fde) |
914 | dprintk(3, "Binary lookup for %lx failed.", pc); | |
690a973f JB |
915 | |
916 | if (fde != NULL) { | |
917 | cie = cie_for_fde(fde, table); | |
4552d5dc | 918 | ptr = (const u8 *)(fde + 2); |
690a973f JB |
919 | if(cie != NULL |
920 | && cie != &bad_cie | |
921 | && cie != ¬_fde | |
922 | && (ptrType = fde_pointer_type(cie)) >= 0 | |
923 | && read_pointer(&ptr, | |
924 | (const u8 *)(fde + 1) + *fde, | |
c65f38d9 | 925 | ptrType, 0, 0) == startLoc) { |
690a973f JB |
926 | if (!(ptrType & DW_EH_PE_indirect)) |
927 | ptrType &= DW_EH_PE_FORM|DW_EH_PE_signed; | |
928 | endLoc = startLoc | |
929 | + read_pointer(&ptr, | |
930 | (const u8 *)(fde + 1) + *fde, | |
c65f38d9 | 931 | ptrType, 0, 0); |
690a973f JB |
932 | if(pc >= endLoc) |
933 | fde = NULL; | |
934 | } else | |
935 | fde = NULL; | |
6d0185ea JB |
936 | if(!fde) |
937 | dprintk(1, "Binary lookup result for %lx discarded.", pc); | |
690a973f JB |
938 | } |
939 | if (fde == NULL) { | |
940 | for (fde = table->address, tableSize = table->size; | |
941 | cie = NULL, tableSize > sizeof(*fde) | |
942 | && tableSize - sizeof(*fde) >= *fde; | |
943 | tableSize -= sizeof(*fde) + *fde, | |
944 | fde += 1 + *fde / sizeof(*fde)) { | |
945 | cie = cie_for_fde(fde, table); | |
946 | if (cie == &bad_cie) { | |
947 | cie = NULL; | |
948 | break; | |
949 | } | |
950 | if (cie == NULL | |
951 | || cie == ¬_fde | |
952 | || (ptrType = fde_pointer_type(cie)) < 0) | |
953 | continue; | |
954 | ptr = (const u8 *)(fde + 2); | |
955 | startLoc = read_pointer(&ptr, | |
956 | (const u8 *)(fde + 1) + *fde, | |
c65f38d9 | 957 | ptrType, 0, 0); |
690a973f JB |
958 | if (!startLoc) |
959 | continue; | |
960 | if (!(ptrType & DW_EH_PE_indirect)) | |
961 | ptrType &= DW_EH_PE_FORM|DW_EH_PE_signed; | |
962 | endLoc = startLoc | |
963 | + read_pointer(&ptr, | |
964 | (const u8 *)(fde + 1) + *fde, | |
c65f38d9 | 965 | ptrType, 0, 0); |
690a973f JB |
966 | if (pc >= startLoc && pc < endLoc) |
967 | break; | |
968 | } | |
6d0185ea JB |
969 | if(!fde) |
970 | dprintk(3, "Linear lookup for %lx failed.", pc); | |
4552d5dc JB |
971 | } |
972 | } | |
973 | if (cie != NULL) { | |
974 | memset(&state, 0, sizeof(state)); | |
975 | state.cieEnd = ptr; /* keep here temporarily */ | |
976 | ptr = (const u8 *)(cie + 2); | |
977 | end = (const u8 *)(cie + 1) + *cie; | |
adf14236 | 978 | frame->call_frame = 1; |
4552d5dc JB |
979 | if ((state.version = *ptr) != 1) |
980 | cie = NULL; /* unsupported version */ | |
981 | else if (*++ptr) { | |
982 | /* check if augmentation size is first (and thus present) */ | |
983 | if (*ptr == 'z') { | |
adf14236 JB |
984 | while (++ptr < end && *ptr) { |
985 | switch(*ptr) { | |
986 | /* check for ignorable (or already handled) | |
987 | * nul-terminated augmentation string */ | |
988 | case 'L': | |
989 | case 'P': | |
990 | case 'R': | |
991 | continue; | |
992 | case 'S': | |
993 | frame->call_frame = 0; | |
994 | continue; | |
995 | default: | |
4552d5dc | 996 | break; |
adf14236 JB |
997 | } |
998 | break; | |
999 | } | |
4552d5dc JB |
1000 | } |
1001 | if (ptr >= end || *ptr) | |
1002 | cie = NULL; | |
1003 | } | |
6d0185ea JB |
1004 | if(!cie) |
1005 | dprintk(1, "CIE unusable (%p,%p).", ptr, end); | |
4552d5dc JB |
1006 | ++ptr; |
1007 | } | |
1008 | if (cie != NULL) { | |
1009 | /* get code aligment factor */ | |
1010 | state.codeAlign = get_uleb128(&ptr, end); | |
1011 | /* get data aligment factor */ | |
1012 | state.dataAlign = get_sleb128(&ptr, end); | |
1013 | if (state.codeAlign == 0 || state.dataAlign == 0 || ptr >= end) | |
1014 | cie = NULL; | |
359ad0d4 | 1015 | else if (UNW_PC(frame) % state.codeAlign |
6d0185ea JB |
1016 | || UNW_SP(frame) % sleb128abs(state.dataAlign)) { |
1017 | dprintk(1, "Input pointer(s) misaligned (%lx,%lx).", | |
1018 | UNW_PC(frame), UNW_SP(frame)); | |
359ad0d4 | 1019 | return -EPERM; |
6d0185ea | 1020 | } else { |
4552d5dc JB |
1021 | retAddrReg = state.version <= 1 ? *ptr++ : get_uleb128(&ptr, end); |
1022 | /* skip augmentation */ | |
ff0a538d JB |
1023 | if (((const char *)(cie + 2))[1] == 'z') { |
1024 | uleb128_t augSize = get_uleb128(&ptr, end); | |
1025 | ||
1026 | ptr += augSize; | |
1027 | } | |
4552d5dc JB |
1028 | if (ptr > end |
1029 | || retAddrReg >= ARRAY_SIZE(reg_info) | |
1030 | || REG_INVALID(retAddrReg) | |
1031 | || reg_info[retAddrReg].width != sizeof(unsigned long)) | |
1032 | cie = NULL; | |
1033 | } | |
6d0185ea JB |
1034 | if(!cie) |
1035 | dprintk(1, "CIE validation failed (%p,%p).", ptr, end); | |
4552d5dc JB |
1036 | } |
1037 | if (cie != NULL) { | |
1038 | state.cieStart = ptr; | |
1039 | ptr = state.cieEnd; | |
1040 | state.cieEnd = end; | |
1041 | end = (const u8 *)(fde + 1) + *fde; | |
1042 | /* skip augmentation */ | |
1043 | if (((const char *)(cie + 2))[1] == 'z') { | |
1044 | uleb128_t augSize = get_uleb128(&ptr, end); | |
1045 | ||
1046 | if ((ptr += augSize) > end) | |
1047 | fde = NULL; | |
1048 | } | |
6d0185ea JB |
1049 | if(!fde) |
1050 | dprintk(1, "FDE validation failed (%p,%p).", ptr, end); | |
4552d5dc JB |
1051 | } |
1052 | if (cie == NULL || fde == NULL) { | |
1053 | #ifdef CONFIG_FRAME_POINTER | |
1054 | unsigned long top, bottom; | |
4552d5dc | 1055 | |
359ad0d4 JB |
1056 | if ((UNW_SP(frame) | UNW_FP(frame)) % sizeof(unsigned long)) |
1057 | return -EPERM; | |
4552d5dc JB |
1058 | top = STACK_TOP(frame->task); |
1059 | bottom = STACK_BOTTOM(frame->task); | |
1060 | # if FRAME_RETADDR_OFFSET < 0 | |
1061 | if (UNW_SP(frame) < top | |
1062 | && UNW_FP(frame) <= UNW_SP(frame) | |
1063 | && bottom < UNW_FP(frame) | |
1064 | # else | |
1065 | if (UNW_SP(frame) > top | |
1066 | && UNW_FP(frame) >= UNW_SP(frame) | |
1067 | && bottom > UNW_FP(frame) | |
1068 | # endif | |
1069 | && !((UNW_SP(frame) | UNW_FP(frame)) | |
1070 | & (sizeof(unsigned long) - 1))) { | |
1071 | unsigned long link; | |
1072 | ||
e2124bb8 | 1073 | if (!probe_kernel_address( |
4552d5dc | 1074 | (unsigned long *)(UNW_FP(frame) |
e2124bb8 AK |
1075 | + FRAME_LINK_OFFSET), |
1076 | link) | |
4552d5dc JB |
1077 | # if FRAME_RETADDR_OFFSET < 0 |
1078 | && link > bottom && link < UNW_FP(frame) | |
1079 | # else | |
1080 | && link > UNW_FP(frame) && link < bottom | |
1081 | # endif | |
1082 | && !(link & (sizeof(link) - 1)) | |
e2124bb8 | 1083 | && !probe_kernel_address( |
4552d5dc | 1084 | (unsigned long *)(UNW_FP(frame) |
e2124bb8 | 1085 | + FRAME_RETADDR_OFFSET), UNW_PC(frame))) { |
4552d5dc JB |
1086 | UNW_SP(frame) = UNW_FP(frame) + FRAME_RETADDR_OFFSET |
1087 | # if FRAME_RETADDR_OFFSET < 0 | |
1088 | - | |
1089 | # else | |
1090 | + | |
1091 | # endif | |
1092 | sizeof(UNW_PC(frame)); | |
1093 | UNW_FP(frame) = link; | |
1094 | return 0; | |
1095 | } | |
1096 | } | |
1097 | #endif | |
1098 | return -ENXIO; | |
1099 | } | |
1100 | state.org = startLoc; | |
1101 | memcpy(&state.cfa, &badCFA, sizeof(state.cfa)); | |
1102 | /* process instructions */ | |
adf14236 | 1103 | if (!processCFI(ptr, end, pc, ptrType, &state) |
4552d5dc JB |
1104 | || state.loc > endLoc |
1105 | || state.regs[retAddrReg].where == Nowhere | |
1106 | || state.cfa.reg >= ARRAY_SIZE(reg_info) | |
1107 | || reg_info[state.cfa.reg].width != sizeof(unsigned long) | |
359ad0d4 | 1108 | || FRAME_REG(state.cfa.reg, unsigned long) % sizeof(unsigned long) |
6d0185ea JB |
1109 | || state.cfa.offs % sizeof(unsigned long)) { |
1110 | dprintk(1, "Unusable unwind info (%p,%p).", ptr, end); | |
4552d5dc | 1111 | return -EIO; |
6d0185ea | 1112 | } |
4552d5dc | 1113 | /* update frame */ |
adf14236 JB |
1114 | #ifndef CONFIG_AS_CFI_SIGNAL_FRAME |
1115 | if(frame->call_frame | |
1116 | && !UNW_DEFAULT_RA(state.regs[retAddrReg], state.dataAlign)) | |
1117 | frame->call_frame = 0; | |
1118 | #endif | |
4552d5dc JB |
1119 | cfa = FRAME_REG(state.cfa.reg, unsigned long) + state.cfa.offs; |
1120 | startLoc = min((unsigned long)UNW_SP(frame), cfa); | |
1121 | endLoc = max((unsigned long)UNW_SP(frame), cfa); | |
1122 | if (STACK_LIMIT(startLoc) != STACK_LIMIT(endLoc)) { | |
1123 | startLoc = min(STACK_LIMIT(cfa), cfa); | |
1124 | endLoc = max(STACK_LIMIT(cfa), cfa); | |
1125 | } | |
1126 | #ifndef CONFIG_64BIT | |
1127 | # define CASES CASE(8); CASE(16); CASE(32) | |
1128 | #else | |
1129 | # define CASES CASE(8); CASE(16); CASE(32); CASE(64) | |
1130 | #endif | |
359ad0d4 JB |
1131 | pc = UNW_PC(frame); |
1132 | sp = UNW_SP(frame); | |
4552d5dc JB |
1133 | for (i = 0; i < ARRAY_SIZE(state.regs); ++i) { |
1134 | if (REG_INVALID(i)) { | |
1135 | if (state.regs[i].where == Nowhere) | |
1136 | continue; | |
6d0185ea JB |
1137 | dprintk(1, "Cannot restore register %u (%d).", |
1138 | i, state.regs[i].where); | |
4552d5dc JB |
1139 | return -EIO; |
1140 | } | |
1141 | switch(state.regs[i].where) { | |
1142 | default: | |
1143 | break; | |
1144 | case Register: | |
1145 | if (state.regs[i].value >= ARRAY_SIZE(reg_info) | |
1146 | || REG_INVALID(state.regs[i].value) | |
6d0185ea JB |
1147 | || reg_info[i].width > reg_info[state.regs[i].value].width) { |
1148 | dprintk(1, "Cannot restore register %u from register %lu.", | |
1149 | i, state.regs[i].value); | |
4552d5dc | 1150 | return -EIO; |
6d0185ea | 1151 | } |
4552d5dc JB |
1152 | switch(reg_info[state.regs[i].value].width) { |
1153 | #define CASE(n) \ | |
1154 | case sizeof(u##n): \ | |
1155 | state.regs[i].value = FRAME_REG(state.regs[i].value, \ | |
1156 | const u##n); \ | |
1157 | break | |
1158 | CASES; | |
1159 | #undef CASE | |
1160 | default: | |
6d0185ea JB |
1161 | dprintk(1, "Unsupported register size %u (%lu).", |
1162 | reg_info[state.regs[i].value].width, | |
1163 | state.regs[i].value); | |
4552d5dc JB |
1164 | return -EIO; |
1165 | } | |
1166 | break; | |
1167 | } | |
1168 | } | |
1169 | for (i = 0; i < ARRAY_SIZE(state.regs); ++i) { | |
1170 | if (REG_INVALID(i)) | |
1171 | continue; | |
1172 | switch(state.regs[i].where) { | |
1173 | case Nowhere: | |
1174 | if (reg_info[i].width != sizeof(UNW_SP(frame)) | |
1175 | || &FRAME_REG(i, __typeof__(UNW_SP(frame))) | |
1176 | != &UNW_SP(frame)) | |
1177 | continue; | |
1178 | UNW_SP(frame) = cfa; | |
1179 | break; | |
1180 | case Register: | |
1181 | switch(reg_info[i].width) { | |
1182 | #define CASE(n) case sizeof(u##n): \ | |
1183 | FRAME_REG(i, u##n) = state.regs[i].value; \ | |
1184 | break | |
1185 | CASES; | |
1186 | #undef CASE | |
1187 | default: | |
6d0185ea JB |
1188 | dprintk(1, "Unsupported register size %u (%u).", |
1189 | reg_info[i].width, i); | |
4552d5dc JB |
1190 | return -EIO; |
1191 | } | |
1192 | break; | |
1193 | case Value: | |
6d0185ea JB |
1194 | if (reg_info[i].width != sizeof(unsigned long)) { |
1195 | dprintk(1, "Unsupported value size %u (%u).", | |
1196 | reg_info[i].width, i); | |
4552d5dc | 1197 | return -EIO; |
6d0185ea | 1198 | } |
4552d5dc JB |
1199 | FRAME_REG(i, unsigned long) = cfa + state.regs[i].value |
1200 | * state.dataAlign; | |
1201 | break; | |
1202 | case Memory: { | |
1203 | unsigned long addr = cfa + state.regs[i].value | |
1204 | * state.dataAlign; | |
1205 | ||
1206 | if ((state.regs[i].value * state.dataAlign) | |
1207 | % sizeof(unsigned long) | |
1208 | || addr < startLoc | |
1209 | || addr + sizeof(unsigned long) < addr | |
6d0185ea JB |
1210 | || addr + sizeof(unsigned long) > endLoc) { |
1211 | dprintk(1, "Bad memory location %lx (%lx).", | |
1212 | addr, state.regs[i].value); | |
4552d5dc | 1213 | return -EIO; |
6d0185ea | 1214 | } |
4552d5dc JB |
1215 | switch(reg_info[i].width) { |
1216 | #define CASE(n) case sizeof(u##n): \ | |
e2124bb8 | 1217 | probe_kernel_address((u##n *)addr, FRAME_REG(i, u##n)); \ |
4552d5dc JB |
1218 | break |
1219 | CASES; | |
1220 | #undef CASE | |
1221 | default: | |
6d0185ea JB |
1222 | dprintk(1, "Unsupported memory size %u (%u).", |
1223 | reg_info[i].width, i); | |
4552d5dc JB |
1224 | return -EIO; |
1225 | } | |
1226 | } | |
1227 | break; | |
1228 | } | |
1229 | } | |
1230 | ||
359ad0d4 | 1231 | if (UNW_PC(frame) % state.codeAlign |
6d0185ea JB |
1232 | || UNW_SP(frame) % sleb128abs(state.dataAlign)) { |
1233 | dprintk(1, "Output pointer(s) misaligned (%lx,%lx).", | |
1234 | UNW_PC(frame), UNW_SP(frame)); | |
359ad0d4 | 1235 | return -EIO; |
6d0185ea JB |
1236 | } |
1237 | if (pc == UNW_PC(frame) && sp == UNW_SP(frame)) { | |
1238 | dprintk(1, "No progress (%lx,%lx).", pc, sp); | |
1239 | return -EIO; | |
1240 | } | |
359ad0d4 | 1241 | |
4552d5dc JB |
1242 | return 0; |
1243 | #undef CASES | |
1244 | #undef FRAME_REG | |
1245 | } | |
1246 | EXPORT_SYMBOL(unwind); | |
1247 | ||
1248 | int unwind_init_frame_info(struct unwind_frame_info *info, | |
1249 | struct task_struct *tsk, | |
1250 | /*const*/ struct pt_regs *regs) | |
1251 | { | |
1252 | info->task = tsk; | |
adf14236 | 1253 | info->call_frame = 0; |
4552d5dc JB |
1254 | arch_unw_init_frame_info(info, regs); |
1255 | ||
1256 | return 0; | |
1257 | } | |
1258 | EXPORT_SYMBOL(unwind_init_frame_info); | |
1259 | ||
1260 | /* | |
1261 | * Prepare to unwind a blocked task. | |
1262 | */ | |
1263 | int unwind_init_blocked(struct unwind_frame_info *info, | |
1264 | struct task_struct *tsk) | |
1265 | { | |
1266 | info->task = tsk; | |
adf14236 | 1267 | info->call_frame = 0; |
4552d5dc JB |
1268 | arch_unw_init_blocked(info); |
1269 | ||
1270 | return 0; | |
1271 | } | |
1272 | EXPORT_SYMBOL(unwind_init_blocked); | |
1273 | ||
1274 | /* | |
1275 | * Prepare to unwind the currently running thread. | |
1276 | */ | |
1277 | int unwind_init_running(struct unwind_frame_info *info, | |
c33bd9aa JB |
1278 | asmlinkage int (*callback)(struct unwind_frame_info *, |
1279 | void *arg), | |
4552d5dc JB |
1280 | void *arg) |
1281 | { | |
1282 | info->task = current; | |
adf14236 | 1283 | info->call_frame = 0; |
4552d5dc | 1284 | |
c33bd9aa | 1285 | return arch_unwind_init_running(info, callback, arg); |
4552d5dc JB |
1286 | } |
1287 | EXPORT_SYMBOL(unwind_init_running); | |
1288 | ||
1289 | /* | |
1290 | * Unwind until the return pointer is in user-land (or until an error | |
1291 | * occurs). Returns 0 if successful, negative number in case of | |
1292 | * error. | |
1293 | */ | |
1294 | int unwind_to_user(struct unwind_frame_info *info) | |
1295 | { | |
1296 | while (!arch_unw_user_mode(info)) { | |
1297 | int err = unwind(info); | |
1298 | ||
1299 | if (err < 0) | |
1300 | return err; | |
1301 | } | |
1302 | ||
1303 | return 0; | |
1304 | } | |
1305 | EXPORT_SYMBOL(unwind_to_user); |