xref: /openbmc/linux/fs/proc/vmcore.c (revision 87c2ce3b)
1 /*
2  *	fs/proc/vmcore.c Interface for accessing the crash
3  * 				 dump from the system's previous life.
4  * 	Heavily borrowed from fs/proc/kcore.c
5  *	Created by: Hariprasad Nellitheertha (hari@in.ibm.com)
6  *	Copyright (C) IBM Corporation, 2004. All rights reserved
7  *
8  */
9 
10 #include <linux/config.h>
11 #include <linux/mm.h>
12 #include <linux/proc_fs.h>
13 #include <linux/user.h>
14 #include <linux/a.out.h>
15 #include <linux/elf.h>
16 #include <linux/elfcore.h>
17 #include <linux/proc_fs.h>
18 #include <linux/highmem.h>
19 #include <linux/bootmem.h>
20 #include <linux/init.h>
21 #include <linux/crash_dump.h>
22 #include <linux/list.h>
23 #include <asm/uaccess.h>
24 #include <asm/io.h>
25 
26 /* List representing chunks of contiguous memory areas and their offsets in
27  * vmcore file.
28  */
29 static LIST_HEAD(vmcore_list);
30 
31 /* Stores the pointer to the buffer containing kernel elf core headers. */
32 static char *elfcorebuf;
33 static size_t elfcorebuf_sz;
34 
35 /* Total size of vmcore file. */
36 static u64 vmcore_size;
37 
38 /* Stores the physical address of elf header of crash image. */
39 unsigned long long elfcorehdr_addr = ELFCORE_ADDR_MAX;
40 
41 struct proc_dir_entry *proc_vmcore = NULL;
42 
43 /* Reads a page from the oldmem device from given offset. */
44 static ssize_t read_from_oldmem(char *buf, size_t count,
45 			     loff_t *ppos, int userbuf)
46 {
47 	unsigned long pfn, offset;
48 	size_t nr_bytes;
49 	ssize_t read = 0, tmp;
50 
51 	if (!count)
52 		return 0;
53 
54 	offset = (unsigned long)(*ppos % PAGE_SIZE);
55 	pfn = (unsigned long)(*ppos / PAGE_SIZE);
56 	if (pfn > saved_max_pfn)
57 		return -EINVAL;
58 
59 	do {
60 		if (count > (PAGE_SIZE - offset))
61 			nr_bytes = PAGE_SIZE - offset;
62 		else
63 			nr_bytes = count;
64 
65 		tmp = copy_oldmem_page(pfn, buf, nr_bytes, offset, userbuf);
66 		if (tmp < 0)
67 			return tmp;
68 		*ppos += nr_bytes;
69 		count -= nr_bytes;
70 		buf += nr_bytes;
71 		read += nr_bytes;
72 		++pfn;
73 		offset = 0;
74 	} while (count);
75 
76 	return read;
77 }
78 
79 /* Maps vmcore file offset to respective physical address in memroy. */
80 static u64 map_offset_to_paddr(loff_t offset, struct list_head *vc_list,
81 					struct vmcore **m_ptr)
82 {
83 	struct vmcore *m;
84 	u64 paddr;
85 
86 	list_for_each_entry(m, vc_list, list) {
87 		u64 start, end;
88 		start = m->offset;
89 		end = m->offset + m->size - 1;
90 		if (offset >= start && offset <= end) {
91 			paddr = m->paddr + offset - start;
92 			*m_ptr = m;
93 			return paddr;
94 		}
95 	}
96 	*m_ptr = NULL;
97 	return 0;
98 }
99 
100 /* Read from the ELF header and then the crash dump. On error, negative value is
101  * returned otherwise number of bytes read are returned.
102  */
103 static ssize_t read_vmcore(struct file *file, char __user *buffer,
104 				size_t buflen, loff_t *fpos)
105 {
106 	ssize_t acc = 0, tmp;
107 	size_t tsz, nr_bytes;
108 	u64 start;
109 	struct vmcore *curr_m = NULL;
110 
111 	if (buflen == 0 || *fpos >= vmcore_size)
112 		return 0;
113 
114 	/* trim buflen to not go beyond EOF */
115 	if (buflen > vmcore_size - *fpos)
116 		buflen = vmcore_size - *fpos;
117 
118 	/* Read ELF core header */
119 	if (*fpos < elfcorebuf_sz) {
120 		tsz = elfcorebuf_sz - *fpos;
121 		if (buflen < tsz)
122 			tsz = buflen;
123 		if (copy_to_user(buffer, elfcorebuf + *fpos, tsz))
124 			return -EFAULT;
125 		buflen -= tsz;
126 		*fpos += tsz;
127 		buffer += tsz;
128 		acc += tsz;
129 
130 		/* leave now if filled buffer already */
131 		if (buflen == 0)
132 			return acc;
133 	}
134 
135 	start = map_offset_to_paddr(*fpos, &vmcore_list, &curr_m);
136 	if (!curr_m)
137         	return -EINVAL;
138 	if ((tsz = (PAGE_SIZE - (start & ~PAGE_MASK))) > buflen)
139 		tsz = buflen;
140 
141 	/* Calculate left bytes in current memory segment. */
142 	nr_bytes = (curr_m->size - (start - curr_m->paddr));
143 	if (tsz > nr_bytes)
144 		tsz = nr_bytes;
145 
146 	while (buflen) {
147 		tmp = read_from_oldmem(buffer, tsz, &start, 1);
148 		if (tmp < 0)
149 			return tmp;
150 		buflen -= tsz;
151 		*fpos += tsz;
152 		buffer += tsz;
153 		acc += tsz;
154 		if (start >= (curr_m->paddr + curr_m->size)) {
155 			if (curr_m->list.next == &vmcore_list)
156 				return acc;	/*EOF*/
157 			curr_m = list_entry(curr_m->list.next,
158 						struct vmcore, list);
159 			start = curr_m->paddr;
160 		}
161 		if ((tsz = (PAGE_SIZE - (start & ~PAGE_MASK))) > buflen)
162 			tsz = buflen;
163 		/* Calculate left bytes in current memory segment. */
164 		nr_bytes = (curr_m->size - (start - curr_m->paddr));
165 		if (tsz > nr_bytes)
166 			tsz = nr_bytes;
167 	}
168 	return acc;
169 }
170 
171 static int open_vmcore(struct inode *inode, struct file *filp)
172 {
173 	return 0;
174 }
175 
176 struct file_operations proc_vmcore_operations = {
177 	.read		= read_vmcore,
178 	.open		= open_vmcore,
179 };
180 
181 static struct vmcore* __init get_new_element(void)
182 {
183 	struct vmcore *p;
184 
185 	p = kmalloc(sizeof(*p), GFP_KERNEL);
186 	if (p)
187 		memset(p, 0, sizeof(*p));
188 	return p;
189 }
190 
191 static u64 __init get_vmcore_size_elf64(char *elfptr)
192 {
193 	int i;
194 	u64 size;
195 	Elf64_Ehdr *ehdr_ptr;
196 	Elf64_Phdr *phdr_ptr;
197 
198 	ehdr_ptr = (Elf64_Ehdr *)elfptr;
199 	phdr_ptr = (Elf64_Phdr*)(elfptr + sizeof(Elf64_Ehdr));
200 	size = sizeof(Elf64_Ehdr) + ((ehdr_ptr->e_phnum) * sizeof(Elf64_Phdr));
201 	for (i = 0; i < ehdr_ptr->e_phnum; i++) {
202 		size += phdr_ptr->p_memsz;
203 		phdr_ptr++;
204 	}
205 	return size;
206 }
207 
208 static u64 __init get_vmcore_size_elf32(char *elfptr)
209 {
210 	int i;
211 	u64 size;
212 	Elf32_Ehdr *ehdr_ptr;
213 	Elf32_Phdr *phdr_ptr;
214 
215 	ehdr_ptr = (Elf32_Ehdr *)elfptr;
216 	phdr_ptr = (Elf32_Phdr*)(elfptr + sizeof(Elf32_Ehdr));
217 	size = sizeof(Elf32_Ehdr) + ((ehdr_ptr->e_phnum) * sizeof(Elf32_Phdr));
218 	for (i = 0; i < ehdr_ptr->e_phnum; i++) {
219 		size += phdr_ptr->p_memsz;
220 		phdr_ptr++;
221 	}
222 	return size;
223 }
224 
225 /* Merges all the PT_NOTE headers into one. */
226 static int __init merge_note_headers_elf64(char *elfptr, size_t *elfsz,
227 						struct list_head *vc_list)
228 {
229 	int i, nr_ptnote=0, rc=0;
230 	char *tmp;
231 	Elf64_Ehdr *ehdr_ptr;
232 	Elf64_Phdr phdr, *phdr_ptr;
233 	Elf64_Nhdr *nhdr_ptr;
234 	u64 phdr_sz = 0, note_off;
235 
236 	ehdr_ptr = (Elf64_Ehdr *)elfptr;
237 	phdr_ptr = (Elf64_Phdr*)(elfptr + sizeof(Elf64_Ehdr));
238 	for (i = 0; i < ehdr_ptr->e_phnum; i++, phdr_ptr++) {
239 		int j;
240 		void *notes_section;
241 		struct vmcore *new;
242 		u64 offset, max_sz, sz, real_sz = 0;
243 		if (phdr_ptr->p_type != PT_NOTE)
244 			continue;
245 		nr_ptnote++;
246 		max_sz = phdr_ptr->p_memsz;
247 		offset = phdr_ptr->p_offset;
248 		notes_section = kmalloc(max_sz, GFP_KERNEL);
249 		if (!notes_section)
250 			return -ENOMEM;
251 		rc = read_from_oldmem(notes_section, max_sz, &offset, 0);
252 		if (rc < 0) {
253 			kfree(notes_section);
254 			return rc;
255 		}
256 		nhdr_ptr = notes_section;
257 		for (j = 0; j < max_sz; j += sz) {
258 			if (nhdr_ptr->n_namesz == 0)
259 				break;
260 			sz = sizeof(Elf64_Nhdr) +
261 				((nhdr_ptr->n_namesz + 3) & ~3) +
262 				((nhdr_ptr->n_descsz + 3) & ~3);
263 			real_sz += sz;
264 			nhdr_ptr = (Elf64_Nhdr*)((char*)nhdr_ptr + sz);
265 		}
266 
267 		/* Add this contiguous chunk of notes section to vmcore list.*/
268 		new = get_new_element();
269 		if (!new) {
270 			kfree(notes_section);
271 			return -ENOMEM;
272 		}
273 		new->paddr = phdr_ptr->p_offset;
274 		new->size = real_sz;
275 		list_add_tail(&new->list, vc_list);
276 		phdr_sz += real_sz;
277 		kfree(notes_section);
278 	}
279 
280 	/* Prepare merged PT_NOTE program header. */
281 	phdr.p_type    = PT_NOTE;
282 	phdr.p_flags   = 0;
283 	note_off = sizeof(Elf64_Ehdr) +
284 			(ehdr_ptr->e_phnum - nr_ptnote +1) * sizeof(Elf64_Phdr);
285 	phdr.p_offset  = note_off;
286 	phdr.p_vaddr   = phdr.p_paddr = 0;
287 	phdr.p_filesz  = phdr.p_memsz = phdr_sz;
288 	phdr.p_align   = 0;
289 
290 	/* Add merged PT_NOTE program header*/
291 	tmp = elfptr + sizeof(Elf64_Ehdr);
292 	memcpy(tmp, &phdr, sizeof(phdr));
293 	tmp += sizeof(phdr);
294 
295 	/* Remove unwanted PT_NOTE program headers. */
296 	i = (nr_ptnote - 1) * sizeof(Elf64_Phdr);
297 	*elfsz = *elfsz - i;
298 	memmove(tmp, tmp+i, ((*elfsz)-sizeof(Elf64_Ehdr)-sizeof(Elf64_Phdr)));
299 
300 	/* Modify e_phnum to reflect merged headers. */
301 	ehdr_ptr->e_phnum = ehdr_ptr->e_phnum - nr_ptnote + 1;
302 
303 	return 0;
304 }
305 
306 /* Merges all the PT_NOTE headers into one. */
307 static int __init merge_note_headers_elf32(char *elfptr, size_t *elfsz,
308 						struct list_head *vc_list)
309 {
310 	int i, nr_ptnote=0, rc=0;
311 	char *tmp;
312 	Elf32_Ehdr *ehdr_ptr;
313 	Elf32_Phdr phdr, *phdr_ptr;
314 	Elf32_Nhdr *nhdr_ptr;
315 	u64 phdr_sz = 0, note_off;
316 
317 	ehdr_ptr = (Elf32_Ehdr *)elfptr;
318 	phdr_ptr = (Elf32_Phdr*)(elfptr + sizeof(Elf32_Ehdr));
319 	for (i = 0; i < ehdr_ptr->e_phnum; i++, phdr_ptr++) {
320 		int j;
321 		void *notes_section;
322 		struct vmcore *new;
323 		u64 offset, max_sz, sz, real_sz = 0;
324 		if (phdr_ptr->p_type != PT_NOTE)
325 			continue;
326 		nr_ptnote++;
327 		max_sz = phdr_ptr->p_memsz;
328 		offset = phdr_ptr->p_offset;
329 		notes_section = kmalloc(max_sz, GFP_KERNEL);
330 		if (!notes_section)
331 			return -ENOMEM;
332 		rc = read_from_oldmem(notes_section, max_sz, &offset, 0);
333 		if (rc < 0) {
334 			kfree(notes_section);
335 			return rc;
336 		}
337 		nhdr_ptr = notes_section;
338 		for (j = 0; j < max_sz; j += sz) {
339 			if (nhdr_ptr->n_namesz == 0)
340 				break;
341 			sz = sizeof(Elf32_Nhdr) +
342 				((nhdr_ptr->n_namesz + 3) & ~3) +
343 				((nhdr_ptr->n_descsz + 3) & ~3);
344 			real_sz += sz;
345 			nhdr_ptr = (Elf32_Nhdr*)((char*)nhdr_ptr + sz);
346 		}
347 
348 		/* Add this contiguous chunk of notes section to vmcore list.*/
349 		new = get_new_element();
350 		if (!new) {
351 			kfree(notes_section);
352 			return -ENOMEM;
353 		}
354 		new->paddr = phdr_ptr->p_offset;
355 		new->size = real_sz;
356 		list_add_tail(&new->list, vc_list);
357 		phdr_sz += real_sz;
358 		kfree(notes_section);
359 	}
360 
361 	/* Prepare merged PT_NOTE program header. */
362 	phdr.p_type    = PT_NOTE;
363 	phdr.p_flags   = 0;
364 	note_off = sizeof(Elf32_Ehdr) +
365 			(ehdr_ptr->e_phnum - nr_ptnote +1) * sizeof(Elf32_Phdr);
366 	phdr.p_offset  = note_off;
367 	phdr.p_vaddr   = phdr.p_paddr = 0;
368 	phdr.p_filesz  = phdr.p_memsz = phdr_sz;
369 	phdr.p_align   = 0;
370 
371 	/* Add merged PT_NOTE program header*/
372 	tmp = elfptr + sizeof(Elf32_Ehdr);
373 	memcpy(tmp, &phdr, sizeof(phdr));
374 	tmp += sizeof(phdr);
375 
376 	/* Remove unwanted PT_NOTE program headers. */
377 	i = (nr_ptnote - 1) * sizeof(Elf32_Phdr);
378 	*elfsz = *elfsz - i;
379 	memmove(tmp, tmp+i, ((*elfsz)-sizeof(Elf32_Ehdr)-sizeof(Elf32_Phdr)));
380 
381 	/* Modify e_phnum to reflect merged headers. */
382 	ehdr_ptr->e_phnum = ehdr_ptr->e_phnum - nr_ptnote + 1;
383 
384 	return 0;
385 }
386 
387 /* Add memory chunks represented by program headers to vmcore list. Also update
388  * the new offset fields of exported program headers. */
389 static int __init process_ptload_program_headers_elf64(char *elfptr,
390 						size_t elfsz,
391 						struct list_head *vc_list)
392 {
393 	int i;
394 	Elf64_Ehdr *ehdr_ptr;
395 	Elf64_Phdr *phdr_ptr;
396 	loff_t vmcore_off;
397 	struct vmcore *new;
398 
399 	ehdr_ptr = (Elf64_Ehdr *)elfptr;
400 	phdr_ptr = (Elf64_Phdr*)(elfptr + sizeof(Elf64_Ehdr)); /* PT_NOTE hdr */
401 
402 	/* First program header is PT_NOTE header. */
403 	vmcore_off = sizeof(Elf64_Ehdr) +
404 			(ehdr_ptr->e_phnum) * sizeof(Elf64_Phdr) +
405 			phdr_ptr->p_memsz; /* Note sections */
406 
407 	for (i = 0; i < ehdr_ptr->e_phnum; i++, phdr_ptr++) {
408 		if (phdr_ptr->p_type != PT_LOAD)
409 			continue;
410 
411 		/* Add this contiguous chunk of memory to vmcore list.*/
412 		new = get_new_element();
413 		if (!new)
414 			return -ENOMEM;
415 		new->paddr = phdr_ptr->p_offset;
416 		new->size = phdr_ptr->p_memsz;
417 		list_add_tail(&new->list, vc_list);
418 
419 		/* Update the program header offset. */
420 		phdr_ptr->p_offset = vmcore_off;
421 		vmcore_off = vmcore_off + phdr_ptr->p_memsz;
422 	}
423 	return 0;
424 }
425 
426 static int __init process_ptload_program_headers_elf32(char *elfptr,
427 						size_t elfsz,
428 						struct list_head *vc_list)
429 {
430 	int i;
431 	Elf32_Ehdr *ehdr_ptr;
432 	Elf32_Phdr *phdr_ptr;
433 	loff_t vmcore_off;
434 	struct vmcore *new;
435 
436 	ehdr_ptr = (Elf32_Ehdr *)elfptr;
437 	phdr_ptr = (Elf32_Phdr*)(elfptr + sizeof(Elf32_Ehdr)); /* PT_NOTE hdr */
438 
439 	/* First program header is PT_NOTE header. */
440 	vmcore_off = sizeof(Elf32_Ehdr) +
441 			(ehdr_ptr->e_phnum) * sizeof(Elf32_Phdr) +
442 			phdr_ptr->p_memsz; /* Note sections */
443 
444 	for (i = 0; i < ehdr_ptr->e_phnum; i++, phdr_ptr++) {
445 		if (phdr_ptr->p_type != PT_LOAD)
446 			continue;
447 
448 		/* Add this contiguous chunk of memory to vmcore list.*/
449 		new = get_new_element();
450 		if (!new)
451 			return -ENOMEM;
452 		new->paddr = phdr_ptr->p_offset;
453 		new->size = phdr_ptr->p_memsz;
454 		list_add_tail(&new->list, vc_list);
455 
456 		/* Update the program header offset */
457 		phdr_ptr->p_offset = vmcore_off;
458 		vmcore_off = vmcore_off + phdr_ptr->p_memsz;
459 	}
460 	return 0;
461 }
462 
463 /* Sets offset fields of vmcore elements. */
464 static void __init set_vmcore_list_offsets_elf64(char *elfptr,
465 						struct list_head *vc_list)
466 {
467 	loff_t vmcore_off;
468 	Elf64_Ehdr *ehdr_ptr;
469 	struct vmcore *m;
470 
471 	ehdr_ptr = (Elf64_Ehdr *)elfptr;
472 
473 	/* Skip Elf header and program headers. */
474 	vmcore_off = sizeof(Elf64_Ehdr) +
475 			(ehdr_ptr->e_phnum) * sizeof(Elf64_Phdr);
476 
477 	list_for_each_entry(m, vc_list, list) {
478 		m->offset = vmcore_off;
479 		vmcore_off += m->size;
480 	}
481 }
482 
483 /* Sets offset fields of vmcore elements. */
484 static void __init set_vmcore_list_offsets_elf32(char *elfptr,
485 						struct list_head *vc_list)
486 {
487 	loff_t vmcore_off;
488 	Elf32_Ehdr *ehdr_ptr;
489 	struct vmcore *m;
490 
491 	ehdr_ptr = (Elf32_Ehdr *)elfptr;
492 
493 	/* Skip Elf header and program headers. */
494 	vmcore_off = sizeof(Elf32_Ehdr) +
495 			(ehdr_ptr->e_phnum) * sizeof(Elf32_Phdr);
496 
497 	list_for_each_entry(m, vc_list, list) {
498 		m->offset = vmcore_off;
499 		vmcore_off += m->size;
500 	}
501 }
502 
503 static int __init parse_crash_elf64_headers(void)
504 {
505 	int rc=0;
506 	Elf64_Ehdr ehdr;
507 	u64 addr;
508 
509 	addr = elfcorehdr_addr;
510 
511 	/* Read Elf header */
512 	rc = read_from_oldmem((char*)&ehdr, sizeof(Elf64_Ehdr), &addr, 0);
513 	if (rc < 0)
514 		return rc;
515 
516 	/* Do some basic Verification. */
517 	if (memcmp(ehdr.e_ident, ELFMAG, SELFMAG) != 0 ||
518 		(ehdr.e_type != ET_CORE) ||
519 		!elf_check_arch(&ehdr) ||
520 		ehdr.e_ident[EI_CLASS] != ELFCLASS64 ||
521 		ehdr.e_ident[EI_VERSION] != EV_CURRENT ||
522 		ehdr.e_version != EV_CURRENT ||
523 		ehdr.e_ehsize != sizeof(Elf64_Ehdr) ||
524 		ehdr.e_phentsize != sizeof(Elf64_Phdr) ||
525 		ehdr.e_phnum == 0) {
526 		printk(KERN_WARNING "Warning: Core image elf header is not"
527 					"sane\n");
528 		return -EINVAL;
529 	}
530 
531 	/* Read in all elf headers. */
532 	elfcorebuf_sz = sizeof(Elf64_Ehdr) + ehdr.e_phnum * sizeof(Elf64_Phdr);
533 	elfcorebuf = kmalloc(elfcorebuf_sz, GFP_KERNEL);
534 	if (!elfcorebuf)
535 		return -ENOMEM;
536 	addr = elfcorehdr_addr;
537 	rc = read_from_oldmem(elfcorebuf, elfcorebuf_sz, &addr, 0);
538 	if (rc < 0) {
539 		kfree(elfcorebuf);
540 		return rc;
541 	}
542 
543 	/* Merge all PT_NOTE headers into one. */
544 	rc = merge_note_headers_elf64(elfcorebuf, &elfcorebuf_sz, &vmcore_list);
545 	if (rc) {
546 		kfree(elfcorebuf);
547 		return rc;
548 	}
549 	rc = process_ptload_program_headers_elf64(elfcorebuf, elfcorebuf_sz,
550 							&vmcore_list);
551 	if (rc) {
552 		kfree(elfcorebuf);
553 		return rc;
554 	}
555 	set_vmcore_list_offsets_elf64(elfcorebuf, &vmcore_list);
556 	return 0;
557 }
558 
559 static int __init parse_crash_elf32_headers(void)
560 {
561 	int rc=0;
562 	Elf32_Ehdr ehdr;
563 	u64 addr;
564 
565 	addr = elfcorehdr_addr;
566 
567 	/* Read Elf header */
568 	rc = read_from_oldmem((char*)&ehdr, sizeof(Elf32_Ehdr), &addr, 0);
569 	if (rc < 0)
570 		return rc;
571 
572 	/* Do some basic Verification. */
573 	if (memcmp(ehdr.e_ident, ELFMAG, SELFMAG) != 0 ||
574 		(ehdr.e_type != ET_CORE) ||
575 		!elf_check_arch(&ehdr) ||
576 		ehdr.e_ident[EI_CLASS] != ELFCLASS32||
577 		ehdr.e_ident[EI_VERSION] != EV_CURRENT ||
578 		ehdr.e_version != EV_CURRENT ||
579 		ehdr.e_ehsize != sizeof(Elf32_Ehdr) ||
580 		ehdr.e_phentsize != sizeof(Elf32_Phdr) ||
581 		ehdr.e_phnum == 0) {
582 		printk(KERN_WARNING "Warning: Core image elf header is not"
583 					"sane\n");
584 		return -EINVAL;
585 	}
586 
587 	/* Read in all elf headers. */
588 	elfcorebuf_sz = sizeof(Elf32_Ehdr) + ehdr.e_phnum * sizeof(Elf32_Phdr);
589 	elfcorebuf = kmalloc(elfcorebuf_sz, GFP_KERNEL);
590 	if (!elfcorebuf)
591 		return -ENOMEM;
592 	addr = elfcorehdr_addr;
593 	rc = read_from_oldmem(elfcorebuf, elfcorebuf_sz, &addr, 0);
594 	if (rc < 0) {
595 		kfree(elfcorebuf);
596 		return rc;
597 	}
598 
599 	/* Merge all PT_NOTE headers into one. */
600 	rc = merge_note_headers_elf32(elfcorebuf, &elfcorebuf_sz, &vmcore_list);
601 	if (rc) {
602 		kfree(elfcorebuf);
603 		return rc;
604 	}
605 	rc = process_ptload_program_headers_elf32(elfcorebuf, elfcorebuf_sz,
606 								&vmcore_list);
607 	if (rc) {
608 		kfree(elfcorebuf);
609 		return rc;
610 	}
611 	set_vmcore_list_offsets_elf32(elfcorebuf, &vmcore_list);
612 	return 0;
613 }
614 
615 static int __init parse_crash_elf_headers(void)
616 {
617 	unsigned char e_ident[EI_NIDENT];
618 	u64 addr;
619 	int rc=0;
620 
621 	addr = elfcorehdr_addr;
622 	rc = read_from_oldmem(e_ident, EI_NIDENT, &addr, 0);
623 	if (rc < 0)
624 		return rc;
625 	if (memcmp(e_ident, ELFMAG, SELFMAG) != 0) {
626 		printk(KERN_WARNING "Warning: Core image elf header"
627 					" not found\n");
628 		return -EINVAL;
629 	}
630 
631 	if (e_ident[EI_CLASS] == ELFCLASS64) {
632 		rc = parse_crash_elf64_headers();
633 		if (rc)
634 			return rc;
635 
636 		/* Determine vmcore size. */
637 		vmcore_size = get_vmcore_size_elf64(elfcorebuf);
638 	} else if (e_ident[EI_CLASS] == ELFCLASS32) {
639 		rc = parse_crash_elf32_headers();
640 		if (rc)
641 			return rc;
642 
643 		/* Determine vmcore size. */
644 		vmcore_size = get_vmcore_size_elf32(elfcorebuf);
645 	} else {
646 		printk(KERN_WARNING "Warning: Core image elf header is not"
647 					" sane\n");
648 		return -EINVAL;
649 	}
650 	return 0;
651 }
652 
653 /* Init function for vmcore module. */
654 static int __init vmcore_init(void)
655 {
656 	int rc = 0;
657 
658 	/* If elfcorehdr= has been passed in cmdline, then capture the dump.*/
659 	if (!(elfcorehdr_addr < ELFCORE_ADDR_MAX))
660 		return rc;
661 	rc = parse_crash_elf_headers();
662 	if (rc) {
663 		printk(KERN_WARNING "Kdump: vmcore not initialized\n");
664 		return rc;
665 	}
666 
667 	/* Initialize /proc/vmcore size if proc is already up. */
668 	if (proc_vmcore)
669 		proc_vmcore->size = vmcore_size;
670 	return 0;
671 }
672 module_init(vmcore_init)
673