xref: /openbmc/linux/fs/proc/vmcore.c (revision f30828a6)
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/mm.h>
11 #include <linux/proc_fs.h>
12 #include <linux/user.h>
13 #include <linux/elf.h>
14 #include <linux/elfcore.h>
15 #include <linux/highmem.h>
16 #include <linux/bootmem.h>
17 #include <linux/init.h>
18 #include <linux/crash_dump.h>
19 #include <linux/list.h>
20 #include <asm/uaccess.h>
21 #include <asm/io.h>
22 
23 /* List representing chunks of contiguous memory areas and their offsets in
24  * vmcore file.
25  */
26 static LIST_HEAD(vmcore_list);
27 
28 /* Stores the pointer to the buffer containing kernel elf core headers. */
29 static char *elfcorebuf;
30 static size_t elfcorebuf_sz;
31 
32 /* Total size of vmcore file. */
33 static u64 vmcore_size;
34 
35 /* Stores the physical address of elf header of crash image. */
36 unsigned long long elfcorehdr_addr = ELFCORE_ADDR_MAX;
37 
38 struct proc_dir_entry *proc_vmcore = NULL;
39 
40 /* Reads a page from the oldmem device from given offset. */
41 static ssize_t read_from_oldmem(char *buf, size_t count,
42 				u64 *ppos, int userbuf)
43 {
44 	unsigned long pfn, offset;
45 	size_t nr_bytes;
46 	ssize_t read = 0, tmp;
47 
48 	if (!count)
49 		return 0;
50 
51 	offset = (unsigned long)(*ppos % PAGE_SIZE);
52 	pfn = (unsigned long)(*ppos / PAGE_SIZE);
53 	if (pfn > saved_max_pfn)
54 		return -EINVAL;
55 
56 	do {
57 		if (count > (PAGE_SIZE - offset))
58 			nr_bytes = PAGE_SIZE - offset;
59 		else
60 			nr_bytes = count;
61 
62 		tmp = copy_oldmem_page(pfn, buf, nr_bytes, offset, userbuf);
63 		if (tmp < 0)
64 			return tmp;
65 		*ppos += nr_bytes;
66 		count -= nr_bytes;
67 		buf += nr_bytes;
68 		read += nr_bytes;
69 		++pfn;
70 		offset = 0;
71 	} while (count);
72 
73 	return read;
74 }
75 
76 /* Maps vmcore file offset to respective physical address in memroy. */
77 static u64 map_offset_to_paddr(loff_t offset, struct list_head *vc_list,
78 					struct vmcore **m_ptr)
79 {
80 	struct vmcore *m;
81 	u64 paddr;
82 
83 	list_for_each_entry(m, vc_list, list) {
84 		u64 start, end;
85 		start = m->offset;
86 		end = m->offset + m->size - 1;
87 		if (offset >= start && offset <= end) {
88 			paddr = m->paddr + offset - start;
89 			*m_ptr = m;
90 			return paddr;
91 		}
92 	}
93 	*m_ptr = NULL;
94 	return 0;
95 }
96 
97 /* Read from the ELF header and then the crash dump. On error, negative value is
98  * returned otherwise number of bytes read are returned.
99  */
100 static ssize_t read_vmcore(struct file *file, char __user *buffer,
101 				size_t buflen, loff_t *fpos)
102 {
103 	ssize_t acc = 0, tmp;
104 	size_t tsz;
105 	u64 start, nr_bytes;
106 	struct vmcore *curr_m = NULL;
107 
108 	if (buflen == 0 || *fpos >= vmcore_size)
109 		return 0;
110 
111 	/* trim buflen to not go beyond EOF */
112 	if (buflen > vmcore_size - *fpos)
113 		buflen = vmcore_size - *fpos;
114 
115 	/* Read ELF core header */
116 	if (*fpos < elfcorebuf_sz) {
117 		tsz = elfcorebuf_sz - *fpos;
118 		if (buflen < tsz)
119 			tsz = buflen;
120 		if (copy_to_user(buffer, elfcorebuf + *fpos, tsz))
121 			return -EFAULT;
122 		buflen -= tsz;
123 		*fpos += tsz;
124 		buffer += tsz;
125 		acc += tsz;
126 
127 		/* leave now if filled buffer already */
128 		if (buflen == 0)
129 			return acc;
130 	}
131 
132 	start = map_offset_to_paddr(*fpos, &vmcore_list, &curr_m);
133 	if (!curr_m)
134         	return -EINVAL;
135 	if ((tsz = (PAGE_SIZE - (start & ~PAGE_MASK))) > buflen)
136 		tsz = buflen;
137 
138 	/* Calculate left bytes in current memory segment. */
139 	nr_bytes = (curr_m->size - (start - curr_m->paddr));
140 	if (tsz > nr_bytes)
141 		tsz = nr_bytes;
142 
143 	while (buflen) {
144 		tmp = read_from_oldmem(buffer, tsz, &start, 1);
145 		if (tmp < 0)
146 			return tmp;
147 		buflen -= tsz;
148 		*fpos += tsz;
149 		buffer += tsz;
150 		acc += tsz;
151 		if (start >= (curr_m->paddr + curr_m->size)) {
152 			if (curr_m->list.next == &vmcore_list)
153 				return acc;	/*EOF*/
154 			curr_m = list_entry(curr_m->list.next,
155 						struct vmcore, list);
156 			start = curr_m->paddr;
157 		}
158 		if ((tsz = (PAGE_SIZE - (start & ~PAGE_MASK))) > buflen)
159 			tsz = buflen;
160 		/* Calculate left bytes in current memory segment. */
161 		nr_bytes = (curr_m->size - (start - curr_m->paddr));
162 		if (tsz > nr_bytes)
163 			tsz = nr_bytes;
164 	}
165 	return acc;
166 }
167 
168 static int open_vmcore(struct inode *inode, struct file *filp)
169 {
170 	return 0;
171 }
172 
173 const struct file_operations proc_vmcore_operations = {
174 	.read		= read_vmcore,
175 	.open		= open_vmcore,
176 };
177 
178 static struct vmcore* __init get_new_element(void)
179 {
180 	struct vmcore *p;
181 
182 	p = kmalloc(sizeof(*p), GFP_KERNEL);
183 	if (p)
184 		memset(p, 0, sizeof(*p));
185 	return p;
186 }
187 
188 static u64 __init get_vmcore_size_elf64(char *elfptr)
189 {
190 	int i;
191 	u64 size;
192 	Elf64_Ehdr *ehdr_ptr;
193 	Elf64_Phdr *phdr_ptr;
194 
195 	ehdr_ptr = (Elf64_Ehdr *)elfptr;
196 	phdr_ptr = (Elf64_Phdr*)(elfptr + sizeof(Elf64_Ehdr));
197 	size = sizeof(Elf64_Ehdr) + ((ehdr_ptr->e_phnum) * sizeof(Elf64_Phdr));
198 	for (i = 0; i < ehdr_ptr->e_phnum; i++) {
199 		size += phdr_ptr->p_memsz;
200 		phdr_ptr++;
201 	}
202 	return size;
203 }
204 
205 static u64 __init get_vmcore_size_elf32(char *elfptr)
206 {
207 	int i;
208 	u64 size;
209 	Elf32_Ehdr *ehdr_ptr;
210 	Elf32_Phdr *phdr_ptr;
211 
212 	ehdr_ptr = (Elf32_Ehdr *)elfptr;
213 	phdr_ptr = (Elf32_Phdr*)(elfptr + sizeof(Elf32_Ehdr));
214 	size = sizeof(Elf32_Ehdr) + ((ehdr_ptr->e_phnum) * sizeof(Elf32_Phdr));
215 	for (i = 0; i < ehdr_ptr->e_phnum; i++) {
216 		size += phdr_ptr->p_memsz;
217 		phdr_ptr++;
218 	}
219 	return size;
220 }
221 
222 /* Merges all the PT_NOTE headers into one. */
223 static int __init merge_note_headers_elf64(char *elfptr, size_t *elfsz,
224 						struct list_head *vc_list)
225 {
226 	int i, nr_ptnote=0, rc=0;
227 	char *tmp;
228 	Elf64_Ehdr *ehdr_ptr;
229 	Elf64_Phdr phdr, *phdr_ptr;
230 	Elf64_Nhdr *nhdr_ptr;
231 	u64 phdr_sz = 0, note_off;
232 
233 	ehdr_ptr = (Elf64_Ehdr *)elfptr;
234 	phdr_ptr = (Elf64_Phdr*)(elfptr + sizeof(Elf64_Ehdr));
235 	for (i = 0; i < ehdr_ptr->e_phnum; i++, phdr_ptr++) {
236 		int j;
237 		void *notes_section;
238 		struct vmcore *new;
239 		u64 offset, max_sz, sz, real_sz = 0;
240 		if (phdr_ptr->p_type != PT_NOTE)
241 			continue;
242 		nr_ptnote++;
243 		max_sz = phdr_ptr->p_memsz;
244 		offset = phdr_ptr->p_offset;
245 		notes_section = kmalloc(max_sz, GFP_KERNEL);
246 		if (!notes_section)
247 			return -ENOMEM;
248 		rc = read_from_oldmem(notes_section, max_sz, &offset, 0);
249 		if (rc < 0) {
250 			kfree(notes_section);
251 			return rc;
252 		}
253 		nhdr_ptr = notes_section;
254 		for (j = 0; j < max_sz; j += sz) {
255 			if (nhdr_ptr->n_namesz == 0)
256 				break;
257 			sz = sizeof(Elf64_Nhdr) +
258 				((nhdr_ptr->n_namesz + 3) & ~3) +
259 				((nhdr_ptr->n_descsz + 3) & ~3);
260 			real_sz += sz;
261 			nhdr_ptr = (Elf64_Nhdr*)((char*)nhdr_ptr + sz);
262 		}
263 
264 		/* Add this contiguous chunk of notes section to vmcore list.*/
265 		new = get_new_element();
266 		if (!new) {
267 			kfree(notes_section);
268 			return -ENOMEM;
269 		}
270 		new->paddr = phdr_ptr->p_offset;
271 		new->size = real_sz;
272 		list_add_tail(&new->list, vc_list);
273 		phdr_sz += real_sz;
274 		kfree(notes_section);
275 	}
276 
277 	/* Prepare merged PT_NOTE program header. */
278 	phdr.p_type    = PT_NOTE;
279 	phdr.p_flags   = 0;
280 	note_off = sizeof(Elf64_Ehdr) +
281 			(ehdr_ptr->e_phnum - nr_ptnote +1) * sizeof(Elf64_Phdr);
282 	phdr.p_offset  = note_off;
283 	phdr.p_vaddr   = phdr.p_paddr = 0;
284 	phdr.p_filesz  = phdr.p_memsz = phdr_sz;
285 	phdr.p_align   = 0;
286 
287 	/* Add merged PT_NOTE program header*/
288 	tmp = elfptr + sizeof(Elf64_Ehdr);
289 	memcpy(tmp, &phdr, sizeof(phdr));
290 	tmp += sizeof(phdr);
291 
292 	/* Remove unwanted PT_NOTE program headers. */
293 	i = (nr_ptnote - 1) * sizeof(Elf64_Phdr);
294 	*elfsz = *elfsz - i;
295 	memmove(tmp, tmp+i, ((*elfsz)-sizeof(Elf64_Ehdr)-sizeof(Elf64_Phdr)));
296 
297 	/* Modify e_phnum to reflect merged headers. */
298 	ehdr_ptr->e_phnum = ehdr_ptr->e_phnum - nr_ptnote + 1;
299 
300 	return 0;
301 }
302 
303 /* Merges all the PT_NOTE headers into one. */
304 static int __init merge_note_headers_elf32(char *elfptr, size_t *elfsz,
305 						struct list_head *vc_list)
306 {
307 	int i, nr_ptnote=0, rc=0;
308 	char *tmp;
309 	Elf32_Ehdr *ehdr_ptr;
310 	Elf32_Phdr phdr, *phdr_ptr;
311 	Elf32_Nhdr *nhdr_ptr;
312 	u64 phdr_sz = 0, note_off;
313 
314 	ehdr_ptr = (Elf32_Ehdr *)elfptr;
315 	phdr_ptr = (Elf32_Phdr*)(elfptr + sizeof(Elf32_Ehdr));
316 	for (i = 0; i < ehdr_ptr->e_phnum; i++, phdr_ptr++) {
317 		int j;
318 		void *notes_section;
319 		struct vmcore *new;
320 		u64 offset, max_sz, sz, real_sz = 0;
321 		if (phdr_ptr->p_type != PT_NOTE)
322 			continue;
323 		nr_ptnote++;
324 		max_sz = phdr_ptr->p_memsz;
325 		offset = phdr_ptr->p_offset;
326 		notes_section = kmalloc(max_sz, GFP_KERNEL);
327 		if (!notes_section)
328 			return -ENOMEM;
329 		rc = read_from_oldmem(notes_section, max_sz, &offset, 0);
330 		if (rc < 0) {
331 			kfree(notes_section);
332 			return rc;
333 		}
334 		nhdr_ptr = notes_section;
335 		for (j = 0; j < max_sz; j += sz) {
336 			if (nhdr_ptr->n_namesz == 0)
337 				break;
338 			sz = sizeof(Elf32_Nhdr) +
339 				((nhdr_ptr->n_namesz + 3) & ~3) +
340 				((nhdr_ptr->n_descsz + 3) & ~3);
341 			real_sz += sz;
342 			nhdr_ptr = (Elf32_Nhdr*)((char*)nhdr_ptr + sz);
343 		}
344 
345 		/* Add this contiguous chunk of notes section to vmcore list.*/
346 		new = get_new_element();
347 		if (!new) {
348 			kfree(notes_section);
349 			return -ENOMEM;
350 		}
351 		new->paddr = phdr_ptr->p_offset;
352 		new->size = real_sz;
353 		list_add_tail(&new->list, vc_list);
354 		phdr_sz += real_sz;
355 		kfree(notes_section);
356 	}
357 
358 	/* Prepare merged PT_NOTE program header. */
359 	phdr.p_type    = PT_NOTE;
360 	phdr.p_flags   = 0;
361 	note_off = sizeof(Elf32_Ehdr) +
362 			(ehdr_ptr->e_phnum - nr_ptnote +1) * sizeof(Elf32_Phdr);
363 	phdr.p_offset  = note_off;
364 	phdr.p_vaddr   = phdr.p_paddr = 0;
365 	phdr.p_filesz  = phdr.p_memsz = phdr_sz;
366 	phdr.p_align   = 0;
367 
368 	/* Add merged PT_NOTE program header*/
369 	tmp = elfptr + sizeof(Elf32_Ehdr);
370 	memcpy(tmp, &phdr, sizeof(phdr));
371 	tmp += sizeof(phdr);
372 
373 	/* Remove unwanted PT_NOTE program headers. */
374 	i = (nr_ptnote - 1) * sizeof(Elf32_Phdr);
375 	*elfsz = *elfsz - i;
376 	memmove(tmp, tmp+i, ((*elfsz)-sizeof(Elf32_Ehdr)-sizeof(Elf32_Phdr)));
377 
378 	/* Modify e_phnum to reflect merged headers. */
379 	ehdr_ptr->e_phnum = ehdr_ptr->e_phnum - nr_ptnote + 1;
380 
381 	return 0;
382 }
383 
384 /* Add memory chunks represented by program headers to vmcore list. Also update
385  * the new offset fields of exported program headers. */
386 static int __init process_ptload_program_headers_elf64(char *elfptr,
387 						size_t elfsz,
388 						struct list_head *vc_list)
389 {
390 	int i;
391 	Elf64_Ehdr *ehdr_ptr;
392 	Elf64_Phdr *phdr_ptr;
393 	loff_t vmcore_off;
394 	struct vmcore *new;
395 
396 	ehdr_ptr = (Elf64_Ehdr *)elfptr;
397 	phdr_ptr = (Elf64_Phdr*)(elfptr + sizeof(Elf64_Ehdr)); /* PT_NOTE hdr */
398 
399 	/* First program header is PT_NOTE header. */
400 	vmcore_off = sizeof(Elf64_Ehdr) +
401 			(ehdr_ptr->e_phnum) * sizeof(Elf64_Phdr) +
402 			phdr_ptr->p_memsz; /* Note sections */
403 
404 	for (i = 0; i < ehdr_ptr->e_phnum; i++, phdr_ptr++) {
405 		if (phdr_ptr->p_type != PT_LOAD)
406 			continue;
407 
408 		/* Add this contiguous chunk of memory to vmcore list.*/
409 		new = get_new_element();
410 		if (!new)
411 			return -ENOMEM;
412 		new->paddr = phdr_ptr->p_offset;
413 		new->size = phdr_ptr->p_memsz;
414 		list_add_tail(&new->list, vc_list);
415 
416 		/* Update the program header offset. */
417 		phdr_ptr->p_offset = vmcore_off;
418 		vmcore_off = vmcore_off + phdr_ptr->p_memsz;
419 	}
420 	return 0;
421 }
422 
423 static int __init process_ptload_program_headers_elf32(char *elfptr,
424 						size_t elfsz,
425 						struct list_head *vc_list)
426 {
427 	int i;
428 	Elf32_Ehdr *ehdr_ptr;
429 	Elf32_Phdr *phdr_ptr;
430 	loff_t vmcore_off;
431 	struct vmcore *new;
432 
433 	ehdr_ptr = (Elf32_Ehdr *)elfptr;
434 	phdr_ptr = (Elf32_Phdr*)(elfptr + sizeof(Elf32_Ehdr)); /* PT_NOTE hdr */
435 
436 	/* First program header is PT_NOTE header. */
437 	vmcore_off = sizeof(Elf32_Ehdr) +
438 			(ehdr_ptr->e_phnum) * sizeof(Elf32_Phdr) +
439 			phdr_ptr->p_memsz; /* Note sections */
440 
441 	for (i = 0; i < ehdr_ptr->e_phnum; i++, phdr_ptr++) {
442 		if (phdr_ptr->p_type != PT_LOAD)
443 			continue;
444 
445 		/* Add this contiguous chunk of memory to vmcore list.*/
446 		new = get_new_element();
447 		if (!new)
448 			return -ENOMEM;
449 		new->paddr = phdr_ptr->p_offset;
450 		new->size = phdr_ptr->p_memsz;
451 		list_add_tail(&new->list, vc_list);
452 
453 		/* Update the program header offset */
454 		phdr_ptr->p_offset = vmcore_off;
455 		vmcore_off = vmcore_off + phdr_ptr->p_memsz;
456 	}
457 	return 0;
458 }
459 
460 /* Sets offset fields of vmcore elements. */
461 static void __init set_vmcore_list_offsets_elf64(char *elfptr,
462 						struct list_head *vc_list)
463 {
464 	loff_t vmcore_off;
465 	Elf64_Ehdr *ehdr_ptr;
466 	struct vmcore *m;
467 
468 	ehdr_ptr = (Elf64_Ehdr *)elfptr;
469 
470 	/* Skip Elf header and program headers. */
471 	vmcore_off = sizeof(Elf64_Ehdr) +
472 			(ehdr_ptr->e_phnum) * sizeof(Elf64_Phdr);
473 
474 	list_for_each_entry(m, vc_list, list) {
475 		m->offset = vmcore_off;
476 		vmcore_off += m->size;
477 	}
478 }
479 
480 /* Sets offset fields of vmcore elements. */
481 static void __init set_vmcore_list_offsets_elf32(char *elfptr,
482 						struct list_head *vc_list)
483 {
484 	loff_t vmcore_off;
485 	Elf32_Ehdr *ehdr_ptr;
486 	struct vmcore *m;
487 
488 	ehdr_ptr = (Elf32_Ehdr *)elfptr;
489 
490 	/* Skip Elf header and program headers. */
491 	vmcore_off = sizeof(Elf32_Ehdr) +
492 			(ehdr_ptr->e_phnum) * sizeof(Elf32_Phdr);
493 
494 	list_for_each_entry(m, vc_list, list) {
495 		m->offset = vmcore_off;
496 		vmcore_off += m->size;
497 	}
498 }
499 
500 static int __init parse_crash_elf64_headers(void)
501 {
502 	int rc=0;
503 	Elf64_Ehdr ehdr;
504 	u64 addr;
505 
506 	addr = elfcorehdr_addr;
507 
508 	/* Read Elf header */
509 	rc = read_from_oldmem((char*)&ehdr, sizeof(Elf64_Ehdr), &addr, 0);
510 	if (rc < 0)
511 		return rc;
512 
513 	/* Do some basic Verification. */
514 	if (memcmp(ehdr.e_ident, ELFMAG, SELFMAG) != 0 ||
515 		(ehdr.e_type != ET_CORE) ||
516 		!vmcore_elf_check_arch(&ehdr) ||
517 		ehdr.e_ident[EI_CLASS] != ELFCLASS64 ||
518 		ehdr.e_ident[EI_VERSION] != EV_CURRENT ||
519 		ehdr.e_version != EV_CURRENT ||
520 		ehdr.e_ehsize != sizeof(Elf64_Ehdr) ||
521 		ehdr.e_phentsize != sizeof(Elf64_Phdr) ||
522 		ehdr.e_phnum == 0) {
523 		printk(KERN_WARNING "Warning: Core image elf header is not"
524 					"sane\n");
525 		return -EINVAL;
526 	}
527 
528 	/* Read in all elf headers. */
529 	elfcorebuf_sz = sizeof(Elf64_Ehdr) + ehdr.e_phnum * sizeof(Elf64_Phdr);
530 	elfcorebuf = kmalloc(elfcorebuf_sz, GFP_KERNEL);
531 	if (!elfcorebuf)
532 		return -ENOMEM;
533 	addr = elfcorehdr_addr;
534 	rc = read_from_oldmem(elfcorebuf, elfcorebuf_sz, &addr, 0);
535 	if (rc < 0) {
536 		kfree(elfcorebuf);
537 		return rc;
538 	}
539 
540 	/* Merge all PT_NOTE headers into one. */
541 	rc = merge_note_headers_elf64(elfcorebuf, &elfcorebuf_sz, &vmcore_list);
542 	if (rc) {
543 		kfree(elfcorebuf);
544 		return rc;
545 	}
546 	rc = process_ptload_program_headers_elf64(elfcorebuf, elfcorebuf_sz,
547 							&vmcore_list);
548 	if (rc) {
549 		kfree(elfcorebuf);
550 		return rc;
551 	}
552 	set_vmcore_list_offsets_elf64(elfcorebuf, &vmcore_list);
553 	return 0;
554 }
555 
556 static int __init parse_crash_elf32_headers(void)
557 {
558 	int rc=0;
559 	Elf32_Ehdr ehdr;
560 	u64 addr;
561 
562 	addr = elfcorehdr_addr;
563 
564 	/* Read Elf header */
565 	rc = read_from_oldmem((char*)&ehdr, sizeof(Elf32_Ehdr), &addr, 0);
566 	if (rc < 0)
567 		return rc;
568 
569 	/* Do some basic Verification. */
570 	if (memcmp(ehdr.e_ident, ELFMAG, SELFMAG) != 0 ||
571 		(ehdr.e_type != ET_CORE) ||
572 		!elf_check_arch(&ehdr) ||
573 		ehdr.e_ident[EI_CLASS] != ELFCLASS32||
574 		ehdr.e_ident[EI_VERSION] != EV_CURRENT ||
575 		ehdr.e_version != EV_CURRENT ||
576 		ehdr.e_ehsize != sizeof(Elf32_Ehdr) ||
577 		ehdr.e_phentsize != sizeof(Elf32_Phdr) ||
578 		ehdr.e_phnum == 0) {
579 		printk(KERN_WARNING "Warning: Core image elf header is not"
580 					"sane\n");
581 		return -EINVAL;
582 	}
583 
584 	/* Read in all elf headers. */
585 	elfcorebuf_sz = sizeof(Elf32_Ehdr) + ehdr.e_phnum * sizeof(Elf32_Phdr);
586 	elfcorebuf = kmalloc(elfcorebuf_sz, GFP_KERNEL);
587 	if (!elfcorebuf)
588 		return -ENOMEM;
589 	addr = elfcorehdr_addr;
590 	rc = read_from_oldmem(elfcorebuf, elfcorebuf_sz, &addr, 0);
591 	if (rc < 0) {
592 		kfree(elfcorebuf);
593 		return rc;
594 	}
595 
596 	/* Merge all PT_NOTE headers into one. */
597 	rc = merge_note_headers_elf32(elfcorebuf, &elfcorebuf_sz, &vmcore_list);
598 	if (rc) {
599 		kfree(elfcorebuf);
600 		return rc;
601 	}
602 	rc = process_ptload_program_headers_elf32(elfcorebuf, elfcorebuf_sz,
603 								&vmcore_list);
604 	if (rc) {
605 		kfree(elfcorebuf);
606 		return rc;
607 	}
608 	set_vmcore_list_offsets_elf32(elfcorebuf, &vmcore_list);
609 	return 0;
610 }
611 
612 static int __init parse_crash_elf_headers(void)
613 {
614 	unsigned char e_ident[EI_NIDENT];
615 	u64 addr;
616 	int rc=0;
617 
618 	addr = elfcorehdr_addr;
619 	rc = read_from_oldmem(e_ident, EI_NIDENT, &addr, 0);
620 	if (rc < 0)
621 		return rc;
622 	if (memcmp(e_ident, ELFMAG, SELFMAG) != 0) {
623 		printk(KERN_WARNING "Warning: Core image elf header"
624 					" not found\n");
625 		return -EINVAL;
626 	}
627 
628 	if (e_ident[EI_CLASS] == ELFCLASS64) {
629 		rc = parse_crash_elf64_headers();
630 		if (rc)
631 			return rc;
632 
633 		/* Determine vmcore size. */
634 		vmcore_size = get_vmcore_size_elf64(elfcorebuf);
635 	} else if (e_ident[EI_CLASS] == ELFCLASS32) {
636 		rc = parse_crash_elf32_headers();
637 		if (rc)
638 			return rc;
639 
640 		/* Determine vmcore size. */
641 		vmcore_size = get_vmcore_size_elf32(elfcorebuf);
642 	} else {
643 		printk(KERN_WARNING "Warning: Core image elf header is not"
644 					" sane\n");
645 		return -EINVAL;
646 	}
647 	return 0;
648 }
649 
650 /* Init function for vmcore module. */
651 static int __init vmcore_init(void)
652 {
653 	int rc = 0;
654 
655 	/* If elfcorehdr= has been passed in cmdline, then capture the dump.*/
656 	if (!(elfcorehdr_addr < ELFCORE_ADDR_MAX))
657 		return rc;
658 	rc = parse_crash_elf_headers();
659 	if (rc) {
660 		printk(KERN_WARNING "Kdump: vmcore not initialized\n");
661 		return rc;
662 	}
663 
664 	/* Initialize /proc/vmcore size if proc is already up. */
665 	if (proc_vmcore)
666 		proc_vmcore->size = vmcore_size;
667 	return 0;
668 }
669 module_init(vmcore_init)
670