blob: a90d6d3541992552d30d2b4a2bac062d352f576d [file] [log] [blame]
Vivek Goyal666bfdd2005-06-25 14:58:21 -07001/*
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
Vivek Goyal666bfdd2005-06-25 14:58:21 -070010#include <linux/mm.h>
David Howells2f96b8c2013-04-12 00:10:25 +010011#include <linux/kcore.h>
Vivek Goyal666bfdd2005-06-25 14:58:21 -070012#include <linux/user.h>
Vivek Goyal666bfdd2005-06-25 14:58:21 -070013#include <linux/elf.h>
14#include <linux/elfcore.h>
Paul Gortmakerafeacc82011-05-26 16:00:52 -040015#include <linux/export.h>
Tejun Heo5a0e3ad2010-03-24 17:04:11 +090016#include <linux/slab.h>
Vivek Goyal666bfdd2005-06-25 14:58:21 -070017#include <linux/highmem.h>
Andrew Morton87ebdc02013-02-27 17:03:16 -080018#include <linux/printk.h>
Vivek Goyal666bfdd2005-06-25 14:58:21 -070019#include <linux/bootmem.h>
20#include <linux/init.h>
21#include <linux/crash_dump.h>
22#include <linux/list.h>
HATAYAMA Daisuke83086972013-07-03 15:02:23 -070023#include <linux/vmalloc.h>
Michael Holzheu9cb21812013-09-11 14:24:51 -070024#include <linux/pagemap.h>
Vivek Goyal666bfdd2005-06-25 14:58:21 -070025#include <asm/uaccess.h>
26#include <asm/io.h>
David Howells2f96b8c2013-04-12 00:10:25 +010027#include "internal.h"
Vivek Goyal666bfdd2005-06-25 14:58:21 -070028
29/* List representing chunks of contiguous memory areas and their offsets in
30 * vmcore file.
31 */
32static LIST_HEAD(vmcore_list);
33
34/* Stores the pointer to the buffer containing kernel elf core headers. */
35static char *elfcorebuf;
36static size_t elfcorebuf_sz;
HATAYAMA Daisukef2bdacd2013-07-03 15:02:14 -070037static size_t elfcorebuf_sz_orig;
Vivek Goyal666bfdd2005-06-25 14:58:21 -070038
HATAYAMA Daisuke087350c2013-07-03 15:02:19 -070039static char *elfnotes_buf;
40static size_t elfnotes_sz;
41
Vivek Goyal666bfdd2005-06-25 14:58:21 -070042/* Total size of vmcore file. */
43static u64 vmcore_size;
44
Fabian Fredericka05e16ad2014-06-06 14:37:04 -070045static struct proc_dir_entry *proc_vmcore;
Vivek Goyal666bfdd2005-06-25 14:58:21 -070046
Olaf Hering997c1362011-05-26 16:25:54 -070047/*
48 * Returns > 0 for RAM pages, 0 for non-RAM pages, < 0 on error
49 * The called function has to take care of module refcounting.
50 */
51static int (*oldmem_pfn_is_ram)(unsigned long pfn);
52
53int register_oldmem_pfn_is_ram(int (*fn)(unsigned long pfn))
54{
55 if (oldmem_pfn_is_ram)
56 return -EBUSY;
57 oldmem_pfn_is_ram = fn;
58 return 0;
59}
60EXPORT_SYMBOL_GPL(register_oldmem_pfn_is_ram);
61
62void unregister_oldmem_pfn_is_ram(void)
63{
64 oldmem_pfn_is_ram = NULL;
65 wmb();
66}
67EXPORT_SYMBOL_GPL(unregister_oldmem_pfn_is_ram);
68
69static int pfn_is_ram(unsigned long pfn)
70{
71 int (*fn)(unsigned long pfn);
72 /* pfn is ram unless fn() checks pagetype */
73 int ret = 1;
74
75 /*
76 * Ask hypervisor if the pfn is really ram.
77 * A ballooned page contains no data and reading from such a page
78 * will cause high load in the hypervisor.
79 */
80 fn = oldmem_pfn_is_ram;
81 if (fn)
82 ret = fn(pfn);
83
84 return ret;
85}
86
Vivek Goyal666bfdd2005-06-25 14:58:21 -070087/* Reads a page from the oldmem device from given offset. */
88static ssize_t read_from_oldmem(char *buf, size_t count,
Vivek Goyal9e9e3942006-01-11 12:17:37 -080089 u64 *ppos, int userbuf)
Vivek Goyal666bfdd2005-06-25 14:58:21 -070090{
91 unsigned long pfn, offset;
92 size_t nr_bytes;
93 ssize_t read = 0, tmp;
94
95 if (!count)
96 return 0;
97
98 offset = (unsigned long)(*ppos % PAGE_SIZE);
99 pfn = (unsigned long)(*ppos / PAGE_SIZE);
Vivek Goyal666bfdd2005-06-25 14:58:21 -0700100
101 do {
102 if (count > (PAGE_SIZE - offset))
103 nr_bytes = PAGE_SIZE - offset;
104 else
105 nr_bytes = count;
106
Olaf Hering997c1362011-05-26 16:25:54 -0700107 /* If pfn is not ram, return zeros for sparse dump files */
108 if (pfn_is_ram(pfn) == 0)
109 memset(buf, 0, nr_bytes);
110 else {
111 tmp = copy_oldmem_page(pfn, buf, nr_bytes,
112 offset, userbuf);
113 if (tmp < 0)
114 return tmp;
115 }
Vivek Goyal666bfdd2005-06-25 14:58:21 -0700116 *ppos += nr_bytes;
117 count -= nr_bytes;
118 buf += nr_bytes;
119 read += nr_bytes;
120 ++pfn;
121 offset = 0;
122 } while (count);
123
124 return read;
125}
126
Michael Holzheube8a8d02013-09-11 14:24:49 -0700127/*
128 * Architectures may override this function to allocate ELF header in 2nd kernel
129 */
130int __weak elfcorehdr_alloc(unsigned long long *addr, unsigned long long *size)
131{
132 return 0;
133}
134
135/*
136 * Architectures may override this function to free header
137 */
138void __weak elfcorehdr_free(unsigned long long addr)
139{}
140
141/*
142 * Architectures may override this function to read from ELF header
143 */
144ssize_t __weak elfcorehdr_read(char *buf, size_t count, u64 *ppos)
145{
146 return read_from_oldmem(buf, count, ppos, 0);
147}
148
149/*
150 * Architectures may override this function to read from notes sections
151 */
152ssize_t __weak elfcorehdr_read_notes(char *buf, size_t count, u64 *ppos)
153{
154 return read_from_oldmem(buf, count, ppos, 0);
155}
156
Michael Holzheu9cb21812013-09-11 14:24:51 -0700157/*
158 * Architectures may override this function to map oldmem
159 */
160int __weak remap_oldmem_pfn_range(struct vm_area_struct *vma,
161 unsigned long from, unsigned long pfn,
162 unsigned long size, pgprot_t prot)
163{
164 return remap_pfn_range(vma, from, pfn, size, prot);
165}
166
167/*
168 * Copy to either kernel or user space
169 */
170static int copy_to(void *target, void *src, size_t size, int userbuf)
171{
172 if (userbuf) {
173 if (copy_to_user((char __user *) target, src, size))
174 return -EFAULT;
175 } else {
176 memcpy(target, src, size);
177 }
178 return 0;
179}
180
Vivek Goyal666bfdd2005-06-25 14:58:21 -0700181/* Read from the ELF header and then the crash dump. On error, negative value is
182 * returned otherwise number of bytes read are returned.
183 */
Michael Holzheu9cb21812013-09-11 14:24:51 -0700184static ssize_t __read_vmcore(char *buffer, size_t buflen, loff_t *fpos,
185 int userbuf)
Vivek Goyal666bfdd2005-06-25 14:58:21 -0700186{
187 ssize_t acc = 0, tmp;
Vivek Goyal80e8ff62006-04-10 22:54:10 -0700188 size_t tsz;
HATAYAMA Daisukeb27eb182013-07-03 15:02:13 -0700189 u64 start;
190 struct vmcore *m = NULL;
Vivek Goyal666bfdd2005-06-25 14:58:21 -0700191
192 if (buflen == 0 || *fpos >= vmcore_size)
193 return 0;
194
195 /* trim buflen to not go beyond EOF */
196 if (buflen > vmcore_size - *fpos)
197 buflen = vmcore_size - *fpos;
198
199 /* Read ELF core header */
200 if (*fpos < elfcorebuf_sz) {
HATAYAMA Daisuke087350c2013-07-03 15:02:19 -0700201 tsz = min(elfcorebuf_sz - (size_t)*fpos, buflen);
Michael Holzheu9cb21812013-09-11 14:24:51 -0700202 if (copy_to(buffer, elfcorebuf + *fpos, tsz, userbuf))
Vivek Goyal666bfdd2005-06-25 14:58:21 -0700203 return -EFAULT;
204 buflen -= tsz;
205 *fpos += tsz;
206 buffer += tsz;
207 acc += tsz;
208
209 /* leave now if filled buffer already */
210 if (buflen == 0)
211 return acc;
212 }
213
HATAYAMA Daisuke087350c2013-07-03 15:02:19 -0700214 /* Read Elf note segment */
215 if (*fpos < elfcorebuf_sz + elfnotes_sz) {
216 void *kaddr;
217
218 tsz = min(elfcorebuf_sz + elfnotes_sz - (size_t)*fpos, buflen);
219 kaddr = elfnotes_buf + *fpos - elfcorebuf_sz;
Michael Holzheu9cb21812013-09-11 14:24:51 -0700220 if (copy_to(buffer, kaddr, tsz, userbuf))
HATAYAMA Daisuke087350c2013-07-03 15:02:19 -0700221 return -EFAULT;
222 buflen -= tsz;
223 *fpos += tsz;
224 buffer += tsz;
225 acc += tsz;
226
227 /* leave now if filled buffer already */
228 if (buflen == 0)
229 return acc;
230 }
231
HATAYAMA Daisukeb27eb182013-07-03 15:02:13 -0700232 list_for_each_entry(m, &vmcore_list, list) {
233 if (*fpos < m->offset + m->size) {
HATAYAMA Daisuke087350c2013-07-03 15:02:19 -0700234 tsz = min_t(size_t, m->offset + m->size - *fpos, buflen);
HATAYAMA Daisukeb27eb182013-07-03 15:02:13 -0700235 start = m->paddr + *fpos - m->offset;
Michael Holzheu9cb21812013-09-11 14:24:51 -0700236 tmp = read_from_oldmem(buffer, tsz, &start, userbuf);
HATAYAMA Daisukeb27eb182013-07-03 15:02:13 -0700237 if (tmp < 0)
238 return tmp;
239 buflen -= tsz;
240 *fpos += tsz;
241 buffer += tsz;
242 acc += tsz;
Vivek Goyal666bfdd2005-06-25 14:58:21 -0700243
HATAYAMA Daisukeb27eb182013-07-03 15:02:13 -0700244 /* leave now if filled buffer already */
245 if (buflen == 0)
246 return acc;
Vivek Goyal666bfdd2005-06-25 14:58:21 -0700247 }
Vivek Goyal666bfdd2005-06-25 14:58:21 -0700248 }
HATAYAMA Daisukeb27eb182013-07-03 15:02:13 -0700249
Vivek Goyal666bfdd2005-06-25 14:58:21 -0700250 return acc;
251}
252
Michael Holzheu9cb21812013-09-11 14:24:51 -0700253static ssize_t read_vmcore(struct file *file, char __user *buffer,
254 size_t buflen, loff_t *fpos)
255{
256 return __read_vmcore((__force char *) buffer, buflen, fpos, 1);
257}
258
259/*
260 * The vmcore fault handler uses the page cache and fills data using the
261 * standard __vmcore_read() function.
262 *
263 * On s390 the fault handler is used for memory regions that can't be mapped
264 * directly with remap_pfn_range().
265 */
266static int mmap_vmcore_fault(struct vm_area_struct *vma, struct vm_fault *vmf)
267{
268#ifdef CONFIG_S390
269 struct address_space *mapping = vma->vm_file->f_mapping;
270 pgoff_t index = vmf->pgoff;
271 struct page *page;
272 loff_t offset;
273 char *buf;
274 int rc;
275
276 page = find_or_create_page(mapping, index, GFP_KERNEL);
277 if (!page)
278 return VM_FAULT_OOM;
279 if (!PageUptodate(page)) {
280 offset = (loff_t) index << PAGE_CACHE_SHIFT;
281 buf = __va((page_to_pfn(page) << PAGE_SHIFT));
282 rc = __read_vmcore(buf, PAGE_SIZE, &offset, 0);
283 if (rc < 0) {
284 unlock_page(page);
285 page_cache_release(page);
286 return (rc == -ENOMEM) ? VM_FAULT_OOM : VM_FAULT_SIGBUS;
287 }
288 SetPageUptodate(page);
289 }
290 unlock_page(page);
291 vmf->page = page;
292 return 0;
293#else
294 return VM_FAULT_SIGBUS;
295#endif
296}
297
298static const struct vm_operations_struct vmcore_mmap_ops = {
299 .fault = mmap_vmcore_fault,
300};
301
HATAYAMA Daisuke83086972013-07-03 15:02:23 -0700302/**
303 * alloc_elfnotes_buf - allocate buffer for ELF note segment in
304 * vmalloc memory
305 *
306 * @notes_sz: size of buffer
307 *
308 * If CONFIG_MMU is defined, use vmalloc_user() to allow users to mmap
309 * the buffer to user-space by means of remap_vmalloc_range().
310 *
311 * If CONFIG_MMU is not defined, use vzalloc() since mmap_vmcore() is
312 * disabled and there's no need to allow users to mmap the buffer.
313 */
314static inline char *alloc_elfnotes_buf(size_t notes_sz)
315{
316#ifdef CONFIG_MMU
317 return vmalloc_user(notes_sz);
318#else
319 return vzalloc(notes_sz);
320#endif
321}
322
323/*
324 * Disable mmap_vmcore() if CONFIG_MMU is not defined. MMU is
325 * essential for mmap_vmcore() in order to map physically
326 * non-contiguous objects (ELF header, ELF note segment and memory
327 * regions in the 1st kernel pointed to by PT_LOAD entries) into
328 * virtually contiguous user-space in ELF layout.
329 */
Michael Holzheu11e376a2013-09-11 14:24:53 -0700330#ifdef CONFIG_MMU
Vitaly Kuznetsov0692ded2014-08-08 14:22:05 -0700331/*
332 * remap_oldmem_pfn_checked - do remap_oldmem_pfn_range replacing all pages
333 * reported as not being ram with the zero page.
334 *
335 * @vma: vm_area_struct describing requested mapping
336 * @from: start remapping from
337 * @pfn: page frame number to start remapping to
338 * @size: remapping size
339 * @prot: protection bits
340 *
341 * Returns zero on success, -EAGAIN on failure.
342 */
343static int remap_oldmem_pfn_checked(struct vm_area_struct *vma,
344 unsigned long from, unsigned long pfn,
345 unsigned long size, pgprot_t prot)
346{
347 unsigned long map_size;
348 unsigned long pos_start, pos_end, pos;
349 unsigned long zeropage_pfn = my_zero_pfn(0);
350 size_t len = 0;
351
352 pos_start = pfn;
353 pos_end = pfn + (size >> PAGE_SHIFT);
354
355 for (pos = pos_start; pos < pos_end; ++pos) {
356 if (!pfn_is_ram(pos)) {
357 /*
358 * We hit a page which is not ram. Remap the continuous
359 * region between pos_start and pos-1 and replace
360 * the non-ram page at pos with the zero page.
361 */
362 if (pos > pos_start) {
363 /* Remap continuous region */
364 map_size = (pos - pos_start) << PAGE_SHIFT;
365 if (remap_oldmem_pfn_range(vma, from + len,
366 pos_start, map_size,
367 prot))
368 goto fail;
369 len += map_size;
370 }
371 /* Remap the zero page */
372 if (remap_oldmem_pfn_range(vma, from + len,
373 zeropage_pfn,
374 PAGE_SIZE, prot))
375 goto fail;
376 len += PAGE_SIZE;
377 pos_start = pos + 1;
378 }
379 }
380 if (pos > pos_start) {
381 /* Remap the rest */
382 map_size = (pos - pos_start) << PAGE_SHIFT;
383 if (remap_oldmem_pfn_range(vma, from + len, pos_start,
384 map_size, prot))
385 goto fail;
386 }
387 return 0;
388fail:
389 do_munmap(vma->vm_mm, from, len);
390 return -EAGAIN;
391}
392
393static int vmcore_remap_oldmem_pfn(struct vm_area_struct *vma,
394 unsigned long from, unsigned long pfn,
395 unsigned long size, pgprot_t prot)
396{
397 /*
398 * Check if oldmem_pfn_is_ram was registered to avoid
399 * looping over all pages without a reason.
400 */
401 if (oldmem_pfn_is_ram)
402 return remap_oldmem_pfn_checked(vma, from, pfn, size, prot);
403 else
404 return remap_oldmem_pfn_range(vma, from, pfn, size, prot);
405}
406
HATAYAMA Daisuke83086972013-07-03 15:02:23 -0700407static int mmap_vmcore(struct file *file, struct vm_area_struct *vma)
408{
409 size_t size = vma->vm_end - vma->vm_start;
410 u64 start, end, len, tsz;
411 struct vmcore *m;
412
413 start = (u64)vma->vm_pgoff << PAGE_SHIFT;
414 end = start + size;
415
416 if (size > vmcore_size || end > vmcore_size)
417 return -EINVAL;
418
419 if (vma->vm_flags & (VM_WRITE | VM_EXEC))
420 return -EPERM;
421
422 vma->vm_flags &= ~(VM_MAYWRITE | VM_MAYEXEC);
423 vma->vm_flags |= VM_MIXEDMAP;
Michael Holzheu9cb21812013-09-11 14:24:51 -0700424 vma->vm_ops = &vmcore_mmap_ops;
HATAYAMA Daisuke83086972013-07-03 15:02:23 -0700425
426 len = 0;
427
428 if (start < elfcorebuf_sz) {
429 u64 pfn;
430
431 tsz = min(elfcorebuf_sz - (size_t)start, size);
432 pfn = __pa(elfcorebuf + start) >> PAGE_SHIFT;
433 if (remap_pfn_range(vma, vma->vm_start, pfn, tsz,
434 vma->vm_page_prot))
435 return -EAGAIN;
436 size -= tsz;
437 start += tsz;
438 len += tsz;
439
440 if (size == 0)
441 return 0;
442 }
443
444 if (start < elfcorebuf_sz + elfnotes_sz) {
445 void *kaddr;
446
447 tsz = min(elfcorebuf_sz + elfnotes_sz - (size_t)start, size);
448 kaddr = elfnotes_buf + start - elfcorebuf_sz;
449 if (remap_vmalloc_range_partial(vma, vma->vm_start + len,
450 kaddr, tsz))
451 goto fail;
452 size -= tsz;
453 start += tsz;
454 len += tsz;
455
456 if (size == 0)
457 return 0;
458 }
459
460 list_for_each_entry(m, &vmcore_list, list) {
461 if (start < m->offset + m->size) {
462 u64 paddr = 0;
463
464 tsz = min_t(size_t, m->offset + m->size - start, size);
465 paddr = m->paddr + start - m->offset;
Vitaly Kuznetsov0692ded2014-08-08 14:22:05 -0700466 if (vmcore_remap_oldmem_pfn(vma, vma->vm_start + len,
467 paddr >> PAGE_SHIFT, tsz,
468 vma->vm_page_prot))
HATAYAMA Daisuke83086972013-07-03 15:02:23 -0700469 goto fail;
470 size -= tsz;
471 start += tsz;
472 len += tsz;
473
474 if (size == 0)
475 return 0;
476 }
477 }
478
479 return 0;
480fail:
481 do_munmap(vma->vm_mm, vma->vm_start, len);
482 return -EAGAIN;
483}
484#else
485static int mmap_vmcore(struct file *file, struct vm_area_struct *vma)
486{
487 return -ENOSYS;
488}
489#endif
490
Alexey Dobriyan5aa140c2008-10-06 14:36:31 +0400491static const struct file_operations proc_vmcore_operations = {
Vivek Goyal666bfdd2005-06-25 14:58:21 -0700492 .read = read_vmcore,
Arnd Bergmannc227e692010-09-22 13:04:54 -0700493 .llseek = default_llseek,
HATAYAMA Daisuke83086972013-07-03 15:02:23 -0700494 .mmap = mmap_vmcore,
Vivek Goyal666bfdd2005-06-25 14:58:21 -0700495};
496
497static struct vmcore* __init get_new_element(void)
498{
Cyrill Gorcunov2f6d3112009-06-17 16:26:00 -0700499 return kzalloc(sizeof(struct vmcore), GFP_KERNEL);
Vivek Goyal666bfdd2005-06-25 14:58:21 -0700500}
501
HATAYAMA Daisuke591ff712013-07-03 15:02:22 -0700502static u64 __init get_vmcore_size(size_t elfsz, size_t elfnotesegsz,
503 struct list_head *vc_list)
Vivek Goyal666bfdd2005-06-25 14:58:21 -0700504{
Vivek Goyal666bfdd2005-06-25 14:58:21 -0700505 u64 size;
HATAYAMA Daisuke591ff712013-07-03 15:02:22 -0700506 struct vmcore *m;
Vivek Goyal666bfdd2005-06-25 14:58:21 -0700507
HATAYAMA Daisuke591ff712013-07-03 15:02:22 -0700508 size = elfsz + elfnotesegsz;
509 list_for_each_entry(m, vc_list, list) {
510 size += m->size;
Vivek Goyal72658e92005-06-25 14:58:22 -0700511 }
512 return size;
513}
514
HATAYAMA Daisuke087350c2013-07-03 15:02:19 -0700515/**
516 * update_note_header_size_elf64 - update p_memsz member of each PT_NOTE entry
517 *
518 * @ehdr_ptr: ELF header
519 *
520 * This function updates p_memsz member of each PT_NOTE entry in the
521 * program header table pointed to by @ehdr_ptr to real size of ELF
522 * note segment.
523 */
524static int __init update_note_header_size_elf64(const Elf64_Ehdr *ehdr_ptr)
Vivek Goyal666bfdd2005-06-25 14:58:21 -0700525{
HATAYAMA Daisuke087350c2013-07-03 15:02:19 -0700526 int i, rc=0;
527 Elf64_Phdr *phdr_ptr;
Vivek Goyal666bfdd2005-06-25 14:58:21 -0700528 Elf64_Nhdr *nhdr_ptr;
Vivek Goyal666bfdd2005-06-25 14:58:21 -0700529
HATAYAMA Daisuke087350c2013-07-03 15:02:19 -0700530 phdr_ptr = (Elf64_Phdr *)(ehdr_ptr + 1);
Vivek Goyal666bfdd2005-06-25 14:58:21 -0700531 for (i = 0; i < ehdr_ptr->e_phnum; i++, phdr_ptr++) {
Vivek Goyal666bfdd2005-06-25 14:58:21 -0700532 void *notes_section;
Vivek Goyal666bfdd2005-06-25 14:58:21 -0700533 u64 offset, max_sz, sz, real_sz = 0;
534 if (phdr_ptr->p_type != PT_NOTE)
535 continue;
Vivek Goyal666bfdd2005-06-25 14:58:21 -0700536 max_sz = phdr_ptr->p_memsz;
537 offset = phdr_ptr->p_offset;
538 notes_section = kmalloc(max_sz, GFP_KERNEL);
539 if (!notes_section)
540 return -ENOMEM;
Michael Holzheube8a8d02013-09-11 14:24:49 -0700541 rc = elfcorehdr_read_notes(notes_section, max_sz, &offset);
Vivek Goyal666bfdd2005-06-25 14:58:21 -0700542 if (rc < 0) {
543 kfree(notes_section);
544 return rc;
545 }
546 nhdr_ptr = notes_section;
Greg Pearson38dfac82014-02-10 14:25:36 -0800547 while (nhdr_ptr->n_namesz != 0) {
Vivek Goyal666bfdd2005-06-25 14:58:21 -0700548 sz = sizeof(Elf64_Nhdr) +
549 ((nhdr_ptr->n_namesz + 3) & ~3) +
550 ((nhdr_ptr->n_descsz + 3) & ~3);
Greg Pearson38dfac82014-02-10 14:25:36 -0800551 if ((real_sz + sz) > max_sz) {
552 pr_warn("Warning: Exceeded p_memsz, dropping PT_NOTE entry n_namesz=0x%x, n_descsz=0x%x\n",
553 nhdr_ptr->n_namesz, nhdr_ptr->n_descsz);
554 break;
555 }
Vivek Goyal666bfdd2005-06-25 14:58:21 -0700556 real_sz += sz;
557 nhdr_ptr = (Elf64_Nhdr*)((char*)nhdr_ptr + sz);
558 }
Vivek Goyal666bfdd2005-06-25 14:58:21 -0700559 kfree(notes_section);
HATAYAMA Daisuke087350c2013-07-03 15:02:19 -0700560 phdr_ptr->p_memsz = real_sz;
Greg Pearson38dfac82014-02-10 14:25:36 -0800561 if (real_sz == 0) {
562 pr_warn("Warning: Zero PT_NOTE entries found\n");
Greg Pearson38dfac82014-02-10 14:25:36 -0800563 }
Vivek Goyal666bfdd2005-06-25 14:58:21 -0700564 }
565
HATAYAMA Daisuke087350c2013-07-03 15:02:19 -0700566 return 0;
567}
568
569/**
570 * get_note_number_and_size_elf64 - get the number of PT_NOTE program
571 * headers and sum of real size of their ELF note segment headers and
572 * data.
573 *
574 * @ehdr_ptr: ELF header
575 * @nr_ptnote: buffer for the number of PT_NOTE program headers
576 * @sz_ptnote: buffer for size of unique PT_NOTE program header
577 *
578 * This function is used to merge multiple PT_NOTE program headers
579 * into a unique single one. The resulting unique entry will have
580 * @sz_ptnote in its phdr->p_mem.
581 *
582 * It is assumed that program headers with PT_NOTE type pointed to by
583 * @ehdr_ptr has already been updated by update_note_header_size_elf64
584 * and each of PT_NOTE program headers has actual ELF note segment
585 * size in its p_memsz member.
586 */
587static int __init get_note_number_and_size_elf64(const Elf64_Ehdr *ehdr_ptr,
588 int *nr_ptnote, u64 *sz_ptnote)
589{
590 int i;
591 Elf64_Phdr *phdr_ptr;
592
593 *nr_ptnote = *sz_ptnote = 0;
594
595 phdr_ptr = (Elf64_Phdr *)(ehdr_ptr + 1);
596 for (i = 0; i < ehdr_ptr->e_phnum; i++, phdr_ptr++) {
597 if (phdr_ptr->p_type != PT_NOTE)
598 continue;
599 *nr_ptnote += 1;
600 *sz_ptnote += phdr_ptr->p_memsz;
601 }
602
603 return 0;
604}
605
606/**
607 * copy_notes_elf64 - copy ELF note segments in a given buffer
608 *
609 * @ehdr_ptr: ELF header
610 * @notes_buf: buffer into which ELF note segments are copied
611 *
612 * This function is used to copy ELF note segment in the 1st kernel
613 * into the buffer @notes_buf in the 2nd kernel. It is assumed that
614 * size of the buffer @notes_buf is equal to or larger than sum of the
615 * real ELF note segment headers and data.
616 *
617 * It is assumed that program headers with PT_NOTE type pointed to by
618 * @ehdr_ptr has already been updated by update_note_header_size_elf64
619 * and each of PT_NOTE program headers has actual ELF note segment
620 * size in its p_memsz member.
621 */
622static int __init copy_notes_elf64(const Elf64_Ehdr *ehdr_ptr, char *notes_buf)
623{
624 int i, rc=0;
625 Elf64_Phdr *phdr_ptr;
626
627 phdr_ptr = (Elf64_Phdr*)(ehdr_ptr + 1);
628
629 for (i = 0; i < ehdr_ptr->e_phnum; i++, phdr_ptr++) {
630 u64 offset;
631 if (phdr_ptr->p_type != PT_NOTE)
632 continue;
633 offset = phdr_ptr->p_offset;
Michael Holzheube8a8d02013-09-11 14:24:49 -0700634 rc = elfcorehdr_read_notes(notes_buf, phdr_ptr->p_memsz,
635 &offset);
HATAYAMA Daisuke087350c2013-07-03 15:02:19 -0700636 if (rc < 0)
637 return rc;
638 notes_buf += phdr_ptr->p_memsz;
639 }
640
641 return 0;
642}
643
644/* Merges all the PT_NOTE headers into one. */
645static int __init merge_note_headers_elf64(char *elfptr, size_t *elfsz,
646 char **notes_buf, size_t *notes_sz)
647{
648 int i, nr_ptnote=0, rc=0;
649 char *tmp;
650 Elf64_Ehdr *ehdr_ptr;
651 Elf64_Phdr phdr;
652 u64 phdr_sz = 0, note_off;
653
654 ehdr_ptr = (Elf64_Ehdr *)elfptr;
655
656 rc = update_note_header_size_elf64(ehdr_ptr);
657 if (rc < 0)
658 return rc;
659
660 rc = get_note_number_and_size_elf64(ehdr_ptr, &nr_ptnote, &phdr_sz);
661 if (rc < 0)
662 return rc;
663
664 *notes_sz = roundup(phdr_sz, PAGE_SIZE);
HATAYAMA Daisuke83086972013-07-03 15:02:23 -0700665 *notes_buf = alloc_elfnotes_buf(*notes_sz);
HATAYAMA Daisuke087350c2013-07-03 15:02:19 -0700666 if (!*notes_buf)
667 return -ENOMEM;
668
669 rc = copy_notes_elf64(ehdr_ptr, *notes_buf);
670 if (rc < 0)
671 return rc;
672
Vivek Goyal666bfdd2005-06-25 14:58:21 -0700673 /* Prepare merged PT_NOTE program header. */
674 phdr.p_type = PT_NOTE;
675 phdr.p_flags = 0;
676 note_off = sizeof(Elf64_Ehdr) +
677 (ehdr_ptr->e_phnum - nr_ptnote +1) * sizeof(Elf64_Phdr);
HATAYAMA Daisuke087350c2013-07-03 15:02:19 -0700678 phdr.p_offset = roundup(note_off, PAGE_SIZE);
Vivek Goyal666bfdd2005-06-25 14:58:21 -0700679 phdr.p_vaddr = phdr.p_paddr = 0;
680 phdr.p_filesz = phdr.p_memsz = phdr_sz;
681 phdr.p_align = 0;
682
683 /* Add merged PT_NOTE program header*/
684 tmp = elfptr + sizeof(Elf64_Ehdr);
685 memcpy(tmp, &phdr, sizeof(phdr));
686 tmp += sizeof(phdr);
687
688 /* Remove unwanted PT_NOTE program headers. */
689 i = (nr_ptnote - 1) * sizeof(Elf64_Phdr);
690 *elfsz = *elfsz - i;
691 memmove(tmp, tmp+i, ((*elfsz)-sizeof(Elf64_Ehdr)-sizeof(Elf64_Phdr)));
HATAYAMA Daisukef2bdacd2013-07-03 15:02:14 -0700692 memset(elfptr + *elfsz, 0, i);
693 *elfsz = roundup(*elfsz, PAGE_SIZE);
Vivek Goyal666bfdd2005-06-25 14:58:21 -0700694
695 /* Modify e_phnum to reflect merged headers. */
696 ehdr_ptr->e_phnum = ehdr_ptr->e_phnum - nr_ptnote + 1;
697
698 return 0;
699}
700
HATAYAMA Daisuke087350c2013-07-03 15:02:19 -0700701/**
702 * update_note_header_size_elf32 - update p_memsz member of each PT_NOTE entry
703 *
704 * @ehdr_ptr: ELF header
705 *
706 * This function updates p_memsz member of each PT_NOTE entry in the
707 * program header table pointed to by @ehdr_ptr to real size of ELF
708 * note segment.
709 */
710static int __init update_note_header_size_elf32(const Elf32_Ehdr *ehdr_ptr)
Vivek Goyal72658e92005-06-25 14:58:22 -0700711{
HATAYAMA Daisuke087350c2013-07-03 15:02:19 -0700712 int i, rc=0;
713 Elf32_Phdr *phdr_ptr;
Vivek Goyal72658e92005-06-25 14:58:22 -0700714 Elf32_Nhdr *nhdr_ptr;
Vivek Goyal72658e92005-06-25 14:58:22 -0700715
HATAYAMA Daisuke087350c2013-07-03 15:02:19 -0700716 phdr_ptr = (Elf32_Phdr *)(ehdr_ptr + 1);
Vivek Goyal72658e92005-06-25 14:58:22 -0700717 for (i = 0; i < ehdr_ptr->e_phnum; i++, phdr_ptr++) {
Vivek Goyal72658e92005-06-25 14:58:22 -0700718 void *notes_section;
Vivek Goyal72658e92005-06-25 14:58:22 -0700719 u64 offset, max_sz, sz, real_sz = 0;
720 if (phdr_ptr->p_type != PT_NOTE)
721 continue;
Vivek Goyal72658e92005-06-25 14:58:22 -0700722 max_sz = phdr_ptr->p_memsz;
723 offset = phdr_ptr->p_offset;
724 notes_section = kmalloc(max_sz, GFP_KERNEL);
725 if (!notes_section)
726 return -ENOMEM;
Michael Holzheube8a8d02013-09-11 14:24:49 -0700727 rc = elfcorehdr_read_notes(notes_section, max_sz, &offset);
Vivek Goyal72658e92005-06-25 14:58:22 -0700728 if (rc < 0) {
729 kfree(notes_section);
730 return rc;
731 }
732 nhdr_ptr = notes_section;
Greg Pearson38dfac82014-02-10 14:25:36 -0800733 while (nhdr_ptr->n_namesz != 0) {
Vivek Goyal72658e92005-06-25 14:58:22 -0700734 sz = sizeof(Elf32_Nhdr) +
735 ((nhdr_ptr->n_namesz + 3) & ~3) +
736 ((nhdr_ptr->n_descsz + 3) & ~3);
Greg Pearson38dfac82014-02-10 14:25:36 -0800737 if ((real_sz + sz) > max_sz) {
738 pr_warn("Warning: Exceeded p_memsz, dropping PT_NOTE entry n_namesz=0x%x, n_descsz=0x%x\n",
739 nhdr_ptr->n_namesz, nhdr_ptr->n_descsz);
740 break;
741 }
Vivek Goyal72658e92005-06-25 14:58:22 -0700742 real_sz += sz;
743 nhdr_ptr = (Elf32_Nhdr*)((char*)nhdr_ptr + sz);
744 }
Vivek Goyal72658e92005-06-25 14:58:22 -0700745 kfree(notes_section);
HATAYAMA Daisuke087350c2013-07-03 15:02:19 -0700746 phdr_ptr->p_memsz = real_sz;
Greg Pearson38dfac82014-02-10 14:25:36 -0800747 if (real_sz == 0) {
748 pr_warn("Warning: Zero PT_NOTE entries found\n");
Greg Pearson38dfac82014-02-10 14:25:36 -0800749 }
Vivek Goyal72658e92005-06-25 14:58:22 -0700750 }
751
HATAYAMA Daisuke087350c2013-07-03 15:02:19 -0700752 return 0;
753}
754
755/**
756 * get_note_number_and_size_elf32 - get the number of PT_NOTE program
757 * headers and sum of real size of their ELF note segment headers and
758 * data.
759 *
760 * @ehdr_ptr: ELF header
761 * @nr_ptnote: buffer for the number of PT_NOTE program headers
762 * @sz_ptnote: buffer for size of unique PT_NOTE program header
763 *
764 * This function is used to merge multiple PT_NOTE program headers
765 * into a unique single one. The resulting unique entry will have
766 * @sz_ptnote in its phdr->p_mem.
767 *
768 * It is assumed that program headers with PT_NOTE type pointed to by
769 * @ehdr_ptr has already been updated by update_note_header_size_elf32
770 * and each of PT_NOTE program headers has actual ELF note segment
771 * size in its p_memsz member.
772 */
773static int __init get_note_number_and_size_elf32(const Elf32_Ehdr *ehdr_ptr,
774 int *nr_ptnote, u64 *sz_ptnote)
775{
776 int i;
777 Elf32_Phdr *phdr_ptr;
778
779 *nr_ptnote = *sz_ptnote = 0;
780
781 phdr_ptr = (Elf32_Phdr *)(ehdr_ptr + 1);
782 for (i = 0; i < ehdr_ptr->e_phnum; i++, phdr_ptr++) {
783 if (phdr_ptr->p_type != PT_NOTE)
784 continue;
785 *nr_ptnote += 1;
786 *sz_ptnote += phdr_ptr->p_memsz;
787 }
788
789 return 0;
790}
791
792/**
793 * copy_notes_elf32 - copy ELF note segments in a given buffer
794 *
795 * @ehdr_ptr: ELF header
796 * @notes_buf: buffer into which ELF note segments are copied
797 *
798 * This function is used to copy ELF note segment in the 1st kernel
799 * into the buffer @notes_buf in the 2nd kernel. It is assumed that
800 * size of the buffer @notes_buf is equal to or larger than sum of the
801 * real ELF note segment headers and data.
802 *
803 * It is assumed that program headers with PT_NOTE type pointed to by
804 * @ehdr_ptr has already been updated by update_note_header_size_elf32
805 * and each of PT_NOTE program headers has actual ELF note segment
806 * size in its p_memsz member.
807 */
808static int __init copy_notes_elf32(const Elf32_Ehdr *ehdr_ptr, char *notes_buf)
809{
810 int i, rc=0;
811 Elf32_Phdr *phdr_ptr;
812
813 phdr_ptr = (Elf32_Phdr*)(ehdr_ptr + 1);
814
815 for (i = 0; i < ehdr_ptr->e_phnum; i++, phdr_ptr++) {
816 u64 offset;
817 if (phdr_ptr->p_type != PT_NOTE)
818 continue;
819 offset = phdr_ptr->p_offset;
Michael Holzheube8a8d02013-09-11 14:24:49 -0700820 rc = elfcorehdr_read_notes(notes_buf, phdr_ptr->p_memsz,
821 &offset);
HATAYAMA Daisuke087350c2013-07-03 15:02:19 -0700822 if (rc < 0)
823 return rc;
824 notes_buf += phdr_ptr->p_memsz;
825 }
826
827 return 0;
828}
829
830/* Merges all the PT_NOTE headers into one. */
831static int __init merge_note_headers_elf32(char *elfptr, size_t *elfsz,
832 char **notes_buf, size_t *notes_sz)
833{
834 int i, nr_ptnote=0, rc=0;
835 char *tmp;
836 Elf32_Ehdr *ehdr_ptr;
837 Elf32_Phdr phdr;
838 u64 phdr_sz = 0, note_off;
839
840 ehdr_ptr = (Elf32_Ehdr *)elfptr;
841
842 rc = update_note_header_size_elf32(ehdr_ptr);
843 if (rc < 0)
844 return rc;
845
846 rc = get_note_number_and_size_elf32(ehdr_ptr, &nr_ptnote, &phdr_sz);
847 if (rc < 0)
848 return rc;
849
850 *notes_sz = roundup(phdr_sz, PAGE_SIZE);
HATAYAMA Daisuke83086972013-07-03 15:02:23 -0700851 *notes_buf = alloc_elfnotes_buf(*notes_sz);
HATAYAMA Daisuke087350c2013-07-03 15:02:19 -0700852 if (!*notes_buf)
853 return -ENOMEM;
854
855 rc = copy_notes_elf32(ehdr_ptr, *notes_buf);
856 if (rc < 0)
857 return rc;
858
Vivek Goyal72658e92005-06-25 14:58:22 -0700859 /* Prepare merged PT_NOTE program header. */
860 phdr.p_type = PT_NOTE;
861 phdr.p_flags = 0;
862 note_off = sizeof(Elf32_Ehdr) +
863 (ehdr_ptr->e_phnum - nr_ptnote +1) * sizeof(Elf32_Phdr);
HATAYAMA Daisuke087350c2013-07-03 15:02:19 -0700864 phdr.p_offset = roundup(note_off, PAGE_SIZE);
Vivek Goyal72658e92005-06-25 14:58:22 -0700865 phdr.p_vaddr = phdr.p_paddr = 0;
866 phdr.p_filesz = phdr.p_memsz = phdr_sz;
867 phdr.p_align = 0;
868
869 /* Add merged PT_NOTE program header*/
870 tmp = elfptr + sizeof(Elf32_Ehdr);
871 memcpy(tmp, &phdr, sizeof(phdr));
872 tmp += sizeof(phdr);
873
874 /* Remove unwanted PT_NOTE program headers. */
875 i = (nr_ptnote - 1) * sizeof(Elf32_Phdr);
876 *elfsz = *elfsz - i;
877 memmove(tmp, tmp+i, ((*elfsz)-sizeof(Elf32_Ehdr)-sizeof(Elf32_Phdr)));
HATAYAMA Daisukef2bdacd2013-07-03 15:02:14 -0700878 memset(elfptr + *elfsz, 0, i);
879 *elfsz = roundup(*elfsz, PAGE_SIZE);
Vivek Goyal72658e92005-06-25 14:58:22 -0700880
881 /* Modify e_phnum to reflect merged headers. */
882 ehdr_ptr->e_phnum = ehdr_ptr->e_phnum - nr_ptnote + 1;
883
884 return 0;
885}
886
Vivek Goyal666bfdd2005-06-25 14:58:21 -0700887/* Add memory chunks represented by program headers to vmcore list. Also update
888 * the new offset fields of exported program headers. */
889static int __init process_ptload_program_headers_elf64(char *elfptr,
890 size_t elfsz,
HATAYAMA Daisuke087350c2013-07-03 15:02:19 -0700891 size_t elfnotes_sz,
Vivek Goyal666bfdd2005-06-25 14:58:21 -0700892 struct list_head *vc_list)
893{
894 int i;
895 Elf64_Ehdr *ehdr_ptr;
896 Elf64_Phdr *phdr_ptr;
897 loff_t vmcore_off;
898 struct vmcore *new;
899
900 ehdr_ptr = (Elf64_Ehdr *)elfptr;
901 phdr_ptr = (Elf64_Phdr*)(elfptr + sizeof(Elf64_Ehdr)); /* PT_NOTE hdr */
902
HATAYAMA Daisuke087350c2013-07-03 15:02:19 -0700903 /* Skip Elf header, program headers and Elf note segment. */
904 vmcore_off = elfsz + elfnotes_sz;
Vivek Goyal666bfdd2005-06-25 14:58:21 -0700905
906 for (i = 0; i < ehdr_ptr->e_phnum; i++, phdr_ptr++) {
HATAYAMA Daisuke7f614cd2013-07-03 15:02:15 -0700907 u64 paddr, start, end, size;
908
Vivek Goyal666bfdd2005-06-25 14:58:21 -0700909 if (phdr_ptr->p_type != PT_LOAD)
910 continue;
911
HATAYAMA Daisuke7f614cd2013-07-03 15:02:15 -0700912 paddr = phdr_ptr->p_offset;
913 start = rounddown(paddr, PAGE_SIZE);
914 end = roundup(paddr + phdr_ptr->p_memsz, PAGE_SIZE);
915 size = end - start;
916
Vivek Goyal666bfdd2005-06-25 14:58:21 -0700917 /* Add this contiguous chunk of memory to vmcore list.*/
918 new = get_new_element();
919 if (!new)
920 return -ENOMEM;
HATAYAMA Daisuke7f614cd2013-07-03 15:02:15 -0700921 new->paddr = start;
922 new->size = size;
Vivek Goyal666bfdd2005-06-25 14:58:21 -0700923 list_add_tail(&new->list, vc_list);
924
925 /* Update the program header offset. */
HATAYAMA Daisuke7f614cd2013-07-03 15:02:15 -0700926 phdr_ptr->p_offset = vmcore_off + (paddr - start);
927 vmcore_off = vmcore_off + size;
Vivek Goyal666bfdd2005-06-25 14:58:21 -0700928 }
929 return 0;
930}
931
Vivek Goyal72658e92005-06-25 14:58:22 -0700932static int __init process_ptload_program_headers_elf32(char *elfptr,
933 size_t elfsz,
HATAYAMA Daisuke087350c2013-07-03 15:02:19 -0700934 size_t elfnotes_sz,
Vivek Goyal72658e92005-06-25 14:58:22 -0700935 struct list_head *vc_list)
936{
937 int i;
938 Elf32_Ehdr *ehdr_ptr;
939 Elf32_Phdr *phdr_ptr;
940 loff_t vmcore_off;
941 struct vmcore *new;
942
943 ehdr_ptr = (Elf32_Ehdr *)elfptr;
944 phdr_ptr = (Elf32_Phdr*)(elfptr + sizeof(Elf32_Ehdr)); /* PT_NOTE hdr */
945
HATAYAMA Daisuke087350c2013-07-03 15:02:19 -0700946 /* Skip Elf header, program headers and Elf note segment. */
947 vmcore_off = elfsz + elfnotes_sz;
Vivek Goyal72658e92005-06-25 14:58:22 -0700948
949 for (i = 0; i < ehdr_ptr->e_phnum; i++, phdr_ptr++) {
HATAYAMA Daisuke7f614cd2013-07-03 15:02:15 -0700950 u64 paddr, start, end, size;
951
Vivek Goyal72658e92005-06-25 14:58:22 -0700952 if (phdr_ptr->p_type != PT_LOAD)
953 continue;
954
HATAYAMA Daisuke7f614cd2013-07-03 15:02:15 -0700955 paddr = phdr_ptr->p_offset;
956 start = rounddown(paddr, PAGE_SIZE);
957 end = roundup(paddr + phdr_ptr->p_memsz, PAGE_SIZE);
958 size = end - start;
959
Vivek Goyal72658e92005-06-25 14:58:22 -0700960 /* Add this contiguous chunk of memory to vmcore list.*/
961 new = get_new_element();
962 if (!new)
963 return -ENOMEM;
HATAYAMA Daisuke7f614cd2013-07-03 15:02:15 -0700964 new->paddr = start;
965 new->size = size;
Vivek Goyal72658e92005-06-25 14:58:22 -0700966 list_add_tail(&new->list, vc_list);
967
968 /* Update the program header offset */
HATAYAMA Daisuke7f614cd2013-07-03 15:02:15 -0700969 phdr_ptr->p_offset = vmcore_off + (paddr - start);
970 vmcore_off = vmcore_off + size;
Vivek Goyal72658e92005-06-25 14:58:22 -0700971 }
972 return 0;
973}
974
Vivek Goyal666bfdd2005-06-25 14:58:21 -0700975/* Sets offset fields of vmcore elements. */
HATAYAMA Daisuke087350c2013-07-03 15:02:19 -0700976static void __init set_vmcore_list_offsets(size_t elfsz, size_t elfnotes_sz,
HATAYAMA Daisukef2bdacd2013-07-03 15:02:14 -0700977 struct list_head *vc_list)
Vivek Goyal666bfdd2005-06-25 14:58:21 -0700978{
979 loff_t vmcore_off;
Vivek Goyal666bfdd2005-06-25 14:58:21 -0700980 struct vmcore *m;
981
HATAYAMA Daisuke087350c2013-07-03 15:02:19 -0700982 /* Skip Elf header, program headers and Elf note segment. */
983 vmcore_off = elfsz + elfnotes_sz;
Vivek Goyal666bfdd2005-06-25 14:58:21 -0700984
985 list_for_each_entry(m, vc_list, list) {
986 m->offset = vmcore_off;
987 vmcore_off += m->size;
988 }
989}
990
HATAYAMA Daisukef2bdacd2013-07-03 15:02:14 -0700991static void free_elfcorebuf(void)
Vivek Goyal72658e92005-06-25 14:58:22 -0700992{
HATAYAMA Daisukef2bdacd2013-07-03 15:02:14 -0700993 free_pages((unsigned long)elfcorebuf, get_order(elfcorebuf_sz_orig));
994 elfcorebuf = NULL;
HATAYAMA Daisuke087350c2013-07-03 15:02:19 -0700995 vfree(elfnotes_buf);
996 elfnotes_buf = NULL;
Vivek Goyal72658e92005-06-25 14:58:22 -0700997}
998
Vivek Goyal666bfdd2005-06-25 14:58:21 -0700999static int __init parse_crash_elf64_headers(void)
1000{
1001 int rc=0;
1002 Elf64_Ehdr ehdr;
1003 u64 addr;
1004
1005 addr = elfcorehdr_addr;
1006
1007 /* Read Elf header */
Michael Holzheube8a8d02013-09-11 14:24:49 -07001008 rc = elfcorehdr_read((char *)&ehdr, sizeof(Elf64_Ehdr), &addr);
Vivek Goyal666bfdd2005-06-25 14:58:21 -07001009 if (rc < 0)
1010 return rc;
1011
1012 /* Do some basic Verification. */
1013 if (memcmp(ehdr.e_ident, ELFMAG, SELFMAG) != 0 ||
1014 (ehdr.e_type != ET_CORE) ||
Mika Westerberg9833c392010-11-19 09:29:24 +01001015 !vmcore_elf64_check_arch(&ehdr) ||
Vivek Goyal666bfdd2005-06-25 14:58:21 -07001016 ehdr.e_ident[EI_CLASS] != ELFCLASS64 ||
1017 ehdr.e_ident[EI_VERSION] != EV_CURRENT ||
1018 ehdr.e_version != EV_CURRENT ||
1019 ehdr.e_ehsize != sizeof(Elf64_Ehdr) ||
1020 ehdr.e_phentsize != sizeof(Elf64_Phdr) ||
1021 ehdr.e_phnum == 0) {
Andrew Morton87ebdc02013-02-27 17:03:16 -08001022 pr_warn("Warning: Core image elf header is not sane\n");
Vivek Goyal666bfdd2005-06-25 14:58:21 -07001023 return -EINVAL;
1024 }
1025
1026 /* Read in all elf headers. */
HATAYAMA Daisukef2bdacd2013-07-03 15:02:14 -07001027 elfcorebuf_sz_orig = sizeof(Elf64_Ehdr) +
1028 ehdr.e_phnum * sizeof(Elf64_Phdr);
1029 elfcorebuf_sz = elfcorebuf_sz_orig;
1030 elfcorebuf = (void *)__get_free_pages(GFP_KERNEL | __GFP_ZERO,
1031 get_order(elfcorebuf_sz_orig));
Vivek Goyal666bfdd2005-06-25 14:58:21 -07001032 if (!elfcorebuf)
1033 return -ENOMEM;
1034 addr = elfcorehdr_addr;
Michael Holzheube8a8d02013-09-11 14:24:49 -07001035 rc = elfcorehdr_read(elfcorebuf, elfcorebuf_sz_orig, &addr);
HATAYAMA Daisukef2bdacd2013-07-03 15:02:14 -07001036 if (rc < 0)
1037 goto fail;
Vivek Goyal666bfdd2005-06-25 14:58:21 -07001038
1039 /* Merge all PT_NOTE headers into one. */
HATAYAMA Daisuke087350c2013-07-03 15:02:19 -07001040 rc = merge_note_headers_elf64(elfcorebuf, &elfcorebuf_sz,
1041 &elfnotes_buf, &elfnotes_sz);
HATAYAMA Daisukef2bdacd2013-07-03 15:02:14 -07001042 if (rc)
1043 goto fail;
Vivek Goyal666bfdd2005-06-25 14:58:21 -07001044 rc = process_ptload_program_headers_elf64(elfcorebuf, elfcorebuf_sz,
HATAYAMA Daisuke087350c2013-07-03 15:02:19 -07001045 elfnotes_sz, &vmcore_list);
HATAYAMA Daisukef2bdacd2013-07-03 15:02:14 -07001046 if (rc)
1047 goto fail;
HATAYAMA Daisuke087350c2013-07-03 15:02:19 -07001048 set_vmcore_list_offsets(elfcorebuf_sz, elfnotes_sz, &vmcore_list);
Vivek Goyal666bfdd2005-06-25 14:58:21 -07001049 return 0;
HATAYAMA Daisukef2bdacd2013-07-03 15:02:14 -07001050fail:
1051 free_elfcorebuf();
1052 return rc;
Vivek Goyal666bfdd2005-06-25 14:58:21 -07001053}
1054
Vivek Goyal72658e92005-06-25 14:58:22 -07001055static int __init parse_crash_elf32_headers(void)
1056{
1057 int rc=0;
1058 Elf32_Ehdr ehdr;
1059 u64 addr;
1060
1061 addr = elfcorehdr_addr;
1062
1063 /* Read Elf header */
Michael Holzheube8a8d02013-09-11 14:24:49 -07001064 rc = elfcorehdr_read((char *)&ehdr, sizeof(Elf32_Ehdr), &addr);
Vivek Goyal72658e92005-06-25 14:58:22 -07001065 if (rc < 0)
1066 return rc;
1067
1068 /* Do some basic Verification. */
1069 if (memcmp(ehdr.e_ident, ELFMAG, SELFMAG) != 0 ||
1070 (ehdr.e_type != ET_CORE) ||
1071 !elf_check_arch(&ehdr) ||
1072 ehdr.e_ident[EI_CLASS] != ELFCLASS32||
1073 ehdr.e_ident[EI_VERSION] != EV_CURRENT ||
1074 ehdr.e_version != EV_CURRENT ||
1075 ehdr.e_ehsize != sizeof(Elf32_Ehdr) ||
1076 ehdr.e_phentsize != sizeof(Elf32_Phdr) ||
1077 ehdr.e_phnum == 0) {
Andrew Morton87ebdc02013-02-27 17:03:16 -08001078 pr_warn("Warning: Core image elf header is not sane\n");
Vivek Goyal72658e92005-06-25 14:58:22 -07001079 return -EINVAL;
1080 }
1081
1082 /* Read in all elf headers. */
HATAYAMA Daisukef2bdacd2013-07-03 15:02:14 -07001083 elfcorebuf_sz_orig = sizeof(Elf32_Ehdr) + ehdr.e_phnum * sizeof(Elf32_Phdr);
1084 elfcorebuf_sz = elfcorebuf_sz_orig;
1085 elfcorebuf = (void *)__get_free_pages(GFP_KERNEL | __GFP_ZERO,
1086 get_order(elfcorebuf_sz_orig));
Vivek Goyal72658e92005-06-25 14:58:22 -07001087 if (!elfcorebuf)
1088 return -ENOMEM;
1089 addr = elfcorehdr_addr;
Michael Holzheube8a8d02013-09-11 14:24:49 -07001090 rc = elfcorehdr_read(elfcorebuf, elfcorebuf_sz_orig, &addr);
HATAYAMA Daisukef2bdacd2013-07-03 15:02:14 -07001091 if (rc < 0)
1092 goto fail;
Vivek Goyal72658e92005-06-25 14:58:22 -07001093
1094 /* Merge all PT_NOTE headers into one. */
HATAYAMA Daisuke087350c2013-07-03 15:02:19 -07001095 rc = merge_note_headers_elf32(elfcorebuf, &elfcorebuf_sz,
1096 &elfnotes_buf, &elfnotes_sz);
HATAYAMA Daisukef2bdacd2013-07-03 15:02:14 -07001097 if (rc)
1098 goto fail;
Vivek Goyal72658e92005-06-25 14:58:22 -07001099 rc = process_ptload_program_headers_elf32(elfcorebuf, elfcorebuf_sz,
HATAYAMA Daisuke087350c2013-07-03 15:02:19 -07001100 elfnotes_sz, &vmcore_list);
HATAYAMA Daisukef2bdacd2013-07-03 15:02:14 -07001101 if (rc)
1102 goto fail;
HATAYAMA Daisuke087350c2013-07-03 15:02:19 -07001103 set_vmcore_list_offsets(elfcorebuf_sz, elfnotes_sz, &vmcore_list);
Vivek Goyal72658e92005-06-25 14:58:22 -07001104 return 0;
HATAYAMA Daisukef2bdacd2013-07-03 15:02:14 -07001105fail:
1106 free_elfcorebuf();
1107 return rc;
Vivek Goyal72658e92005-06-25 14:58:22 -07001108}
1109
Vivek Goyal666bfdd2005-06-25 14:58:21 -07001110static int __init parse_crash_elf_headers(void)
1111{
1112 unsigned char e_ident[EI_NIDENT];
1113 u64 addr;
1114 int rc=0;
1115
1116 addr = elfcorehdr_addr;
Michael Holzheube8a8d02013-09-11 14:24:49 -07001117 rc = elfcorehdr_read(e_ident, EI_NIDENT, &addr);
Vivek Goyal666bfdd2005-06-25 14:58:21 -07001118 if (rc < 0)
1119 return rc;
1120 if (memcmp(e_ident, ELFMAG, SELFMAG) != 0) {
Andrew Morton87ebdc02013-02-27 17:03:16 -08001121 pr_warn("Warning: Core image elf header not found\n");
Vivek Goyal666bfdd2005-06-25 14:58:21 -07001122 return -EINVAL;
1123 }
1124
1125 if (e_ident[EI_CLASS] == ELFCLASS64) {
1126 rc = parse_crash_elf64_headers();
1127 if (rc)
1128 return rc;
Vivek Goyal72658e92005-06-25 14:58:22 -07001129 } else if (e_ident[EI_CLASS] == ELFCLASS32) {
1130 rc = parse_crash_elf32_headers();
1131 if (rc)
1132 return rc;
Vivek Goyal666bfdd2005-06-25 14:58:21 -07001133 } else {
Andrew Morton87ebdc02013-02-27 17:03:16 -08001134 pr_warn("Warning: Core image elf header is not sane\n");
Vivek Goyal666bfdd2005-06-25 14:58:21 -07001135 return -EINVAL;
1136 }
HATAYAMA Daisuke591ff712013-07-03 15:02:22 -07001137
1138 /* Determine vmcore size. */
1139 vmcore_size = get_vmcore_size(elfcorebuf_sz, elfnotes_sz,
1140 &vmcore_list);
1141
Vivek Goyal666bfdd2005-06-25 14:58:21 -07001142 return 0;
1143}
1144
1145/* Init function for vmcore module. */
1146static int __init vmcore_init(void)
1147{
1148 int rc = 0;
1149
Michael Holzheube8a8d02013-09-11 14:24:49 -07001150 /* Allow architectures to allocate ELF header in 2nd kernel */
1151 rc = elfcorehdr_alloc(&elfcorehdr_addr, &elfcorehdr_size);
1152 if (rc)
1153 return rc;
1154 /*
1155 * If elfcorehdr= has been passed in cmdline or created in 2nd kernel,
1156 * then capture the dump.
1157 */
Simon Horman85a0ee32008-10-18 20:28:29 -07001158 if (!(is_vmcore_usable()))
Vivek Goyal666bfdd2005-06-25 14:58:21 -07001159 return rc;
1160 rc = parse_crash_elf_headers();
1161 if (rc) {
Andrew Morton87ebdc02013-02-27 17:03:16 -08001162 pr_warn("Kdump: vmcore not initialized\n");
Vivek Goyal666bfdd2005-06-25 14:58:21 -07001163 return rc;
1164 }
Michael Holzheube8a8d02013-09-11 14:24:49 -07001165 elfcorehdr_free(elfcorehdr_addr);
1166 elfcorehdr_addr = ELFCORE_ADDR_ERR;
Vivek Goyal666bfdd2005-06-25 14:58:21 -07001167
Alexey Dobriyan5aa140c2008-10-06 14:36:31 +04001168 proc_vmcore = proc_create("vmcore", S_IRUSR, NULL, &proc_vmcore_operations);
Vivek Goyal666bfdd2005-06-25 14:58:21 -07001169 if (proc_vmcore)
1170 proc_vmcore->size = vmcore_size;
1171 return 0;
1172}
Paul Gortmakerabaf3782014-01-23 15:55:45 -08001173fs_initcall(vmcore_init);
Mahesh Salgaonkar162573932012-02-16 01:15:00 +00001174
1175/* Cleanup function for vmcore module. */
1176void vmcore_cleanup(void)
1177{
1178 struct list_head *pos, *next;
1179
1180 if (proc_vmcore) {
David Howellsa8ca16e2013-04-12 17:27:28 +01001181 proc_remove(proc_vmcore);
Mahesh Salgaonkar162573932012-02-16 01:15:00 +00001182 proc_vmcore = NULL;
1183 }
1184
1185 /* clear the vmcore list. */
1186 list_for_each_safe(pos, next, &vmcore_list) {
1187 struct vmcore *m;
1188
1189 m = list_entry(pos, struct vmcore, list);
1190 list_del(&m->list);
1191 kfree(m);
1192 }
HATAYAMA Daisukef2bdacd2013-07-03 15:02:14 -07001193 free_elfcorebuf();
Mahesh Salgaonkar162573932012-02-16 01:15:00 +00001194}