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Commit | Line | Data |
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40b0b3f8 | 1 | // SPDX-License-Identifier: GPL-2.0-only |
a43cac0d DY |
2 | /* |
3 | * kexec: kexec_file_load system call | |
4 | * | |
5 | * Copyright (C) 2014 Red Hat Inc. | |
6 | * Authors: | |
7 | * Vivek Goyal <vgoyal@redhat.com> | |
a43cac0d DY |
8 | */ |
9 | ||
de90a6bc MH |
10 | #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt |
11 | ||
a43cac0d DY |
12 | #include <linux/capability.h> |
13 | #include <linux/mm.h> | |
14 | #include <linux/file.h> | |
15 | #include <linux/slab.h> | |
16 | #include <linux/kexec.h> | |
735c2f90 | 17 | #include <linux/memblock.h> |
a43cac0d DY |
18 | #include <linux/mutex.h> |
19 | #include <linux/list.h> | |
b804defe | 20 | #include <linux/fs.h> |
7b8589cc | 21 | #include <linux/ima.h> |
a43cac0d DY |
22 | #include <crypto/hash.h> |
23 | #include <crypto/sha.h> | |
babac4a8 AT |
24 | #include <linux/elf.h> |
25 | #include <linux/elfcore.h> | |
26 | #include <linux/kernel.h> | |
a43cac0d DY |
27 | #include <linux/syscalls.h> |
28 | #include <linux/vmalloc.h> | |
29 | #include "kexec_internal.h" | |
30 | ||
a43cac0d DY |
31 | static int kexec_calculate_store_digests(struct kimage *image); |
32 | ||
9ec4ecef AT |
33 | /* |
34 | * Currently this is the only default function that is exported as some | |
35 | * architectures need it to do additional handlings. | |
36 | * In the future, other default functions may be exported too if required. | |
37 | */ | |
38 | int kexec_image_probe_default(struct kimage *image, void *buf, | |
39 | unsigned long buf_len) | |
40 | { | |
41 | const struct kexec_file_ops * const *fops; | |
42 | int ret = -ENOEXEC; | |
43 | ||
44 | for (fops = &kexec_file_loaders[0]; *fops && (*fops)->probe; ++fops) { | |
45 | ret = (*fops)->probe(buf, buf_len); | |
46 | if (!ret) { | |
47 | image->fops = *fops; | |
48 | return ret; | |
49 | } | |
50 | } | |
51 | ||
52 | return ret; | |
53 | } | |
54 | ||
a43cac0d DY |
55 | /* Architectures can provide this probe function */ |
56 | int __weak arch_kexec_kernel_image_probe(struct kimage *image, void *buf, | |
57 | unsigned long buf_len) | |
58 | { | |
9ec4ecef AT |
59 | return kexec_image_probe_default(image, buf, buf_len); |
60 | } | |
61 | ||
62 | static void *kexec_image_load_default(struct kimage *image) | |
63 | { | |
64 | if (!image->fops || !image->fops->load) | |
65 | return ERR_PTR(-ENOEXEC); | |
66 | ||
67 | return image->fops->load(image, image->kernel_buf, | |
68 | image->kernel_buf_len, image->initrd_buf, | |
69 | image->initrd_buf_len, image->cmdline_buf, | |
70 | image->cmdline_buf_len); | |
a43cac0d DY |
71 | } |
72 | ||
73 | void * __weak arch_kexec_kernel_image_load(struct kimage *image) | |
74 | { | |
9ec4ecef AT |
75 | return kexec_image_load_default(image); |
76 | } | |
77 | ||
92a98a2b | 78 | int kexec_image_post_load_cleanup_default(struct kimage *image) |
9ec4ecef AT |
79 | { |
80 | if (!image->fops || !image->fops->cleanup) | |
81 | return 0; | |
82 | ||
83 | return image->fops->cleanup(image->image_loader_data); | |
a43cac0d DY |
84 | } |
85 | ||
86 | int __weak arch_kimage_file_post_load_cleanup(struct kimage *image) | |
87 | { | |
9ec4ecef | 88 | return kexec_image_post_load_cleanup_default(image); |
a43cac0d DY |
89 | } |
90 | ||
978e30c9 | 91 | #ifdef CONFIG_KEXEC_VERIFY_SIG |
9ec4ecef AT |
92 | static int kexec_image_verify_sig_default(struct kimage *image, void *buf, |
93 | unsigned long buf_len) | |
94 | { | |
95 | if (!image->fops || !image->fops->verify_sig) { | |
96 | pr_debug("kernel loader does not support signature verification.\n"); | |
97 | return -EKEYREJECTED; | |
98 | } | |
99 | ||
100 | return image->fops->verify_sig(buf, buf_len); | |
101 | } | |
102 | ||
a43cac0d DY |
103 | int __weak arch_kexec_kernel_verify_sig(struct kimage *image, void *buf, |
104 | unsigned long buf_len) | |
105 | { | |
9ec4ecef | 106 | return kexec_image_verify_sig_default(image, buf, buf_len); |
a43cac0d | 107 | } |
978e30c9 | 108 | #endif |
a43cac0d | 109 | |
8aec395b PR |
110 | /* |
111 | * arch_kexec_apply_relocations_add - apply relocations of type RELA | |
112 | * @pi: Purgatory to be relocated. | |
113 | * @section: Section relocations applying to. | |
114 | * @relsec: Section containing RELAs. | |
115 | * @symtab: Corresponding symtab. | |
116 | * | |
117 | * Return: 0 on success, negative errno on error. | |
118 | */ | |
a43cac0d | 119 | int __weak |
8aec395b PR |
120 | arch_kexec_apply_relocations_add(struct purgatory_info *pi, Elf_Shdr *section, |
121 | const Elf_Shdr *relsec, const Elf_Shdr *symtab) | |
a43cac0d DY |
122 | { |
123 | pr_err("RELA relocation unsupported.\n"); | |
124 | return -ENOEXEC; | |
125 | } | |
126 | ||
8aec395b PR |
127 | /* |
128 | * arch_kexec_apply_relocations - apply relocations of type REL | |
129 | * @pi: Purgatory to be relocated. | |
130 | * @section: Section relocations applying to. | |
131 | * @relsec: Section containing RELs. | |
132 | * @symtab: Corresponding symtab. | |
133 | * | |
134 | * Return: 0 on success, negative errno on error. | |
135 | */ | |
a43cac0d | 136 | int __weak |
8aec395b PR |
137 | arch_kexec_apply_relocations(struct purgatory_info *pi, Elf_Shdr *section, |
138 | const Elf_Shdr *relsec, const Elf_Shdr *symtab) | |
a43cac0d DY |
139 | { |
140 | pr_err("REL relocation unsupported.\n"); | |
141 | return -ENOEXEC; | |
142 | } | |
143 | ||
144 | /* | |
145 | * Free up memory used by kernel, initrd, and command line. This is temporary | |
146 | * memory allocation which is not needed any more after these buffers have | |
147 | * been loaded into separate segments and have been copied elsewhere. | |
148 | */ | |
149 | void kimage_file_post_load_cleanup(struct kimage *image) | |
150 | { | |
151 | struct purgatory_info *pi = &image->purgatory_info; | |
152 | ||
153 | vfree(image->kernel_buf); | |
154 | image->kernel_buf = NULL; | |
155 | ||
156 | vfree(image->initrd_buf); | |
157 | image->initrd_buf = NULL; | |
158 | ||
159 | kfree(image->cmdline_buf); | |
160 | image->cmdline_buf = NULL; | |
161 | ||
162 | vfree(pi->purgatory_buf); | |
163 | pi->purgatory_buf = NULL; | |
164 | ||
165 | vfree(pi->sechdrs); | |
166 | pi->sechdrs = NULL; | |
167 | ||
168 | /* See if architecture has anything to cleanup post load */ | |
169 | arch_kimage_file_post_load_cleanup(image); | |
170 | ||
171 | /* | |
172 | * Above call should have called into bootloader to free up | |
173 | * any data stored in kimage->image_loader_data. It should | |
174 | * be ok now to free it up. | |
175 | */ | |
176 | kfree(image->image_loader_data); | |
177 | image->image_loader_data = NULL; | |
178 | } | |
179 | ||
180 | /* | |
181 | * In file mode list of segments is prepared by kernel. Copy relevant | |
182 | * data from user space, do error checking, prepare segment list | |
183 | */ | |
184 | static int | |
185 | kimage_file_prepare_segments(struct kimage *image, int kernel_fd, int initrd_fd, | |
186 | const char __user *cmdline_ptr, | |
187 | unsigned long cmdline_len, unsigned flags) | |
188 | { | |
189 | int ret = 0; | |
190 | void *ldata; | |
b804defe | 191 | loff_t size; |
a43cac0d | 192 | |
b804defe MZ |
193 | ret = kernel_read_file_from_fd(kernel_fd, &image->kernel_buf, |
194 | &size, INT_MAX, READING_KEXEC_IMAGE); | |
a43cac0d DY |
195 | if (ret) |
196 | return ret; | |
b804defe | 197 | image->kernel_buf_len = size; |
a43cac0d | 198 | |
7b8589cc MZ |
199 | /* IMA needs to pass the measurement list to the next kernel. */ |
200 | ima_add_kexec_buffer(image); | |
201 | ||
a43cac0d DY |
202 | /* Call arch image probe handlers */ |
203 | ret = arch_kexec_kernel_image_probe(image, image->kernel_buf, | |
204 | image->kernel_buf_len); | |
a43cac0d DY |
205 | if (ret) |
206 | goto out; | |
207 | ||
208 | #ifdef CONFIG_KEXEC_VERIFY_SIG | |
209 | ret = arch_kexec_kernel_verify_sig(image, image->kernel_buf, | |
210 | image->kernel_buf_len); | |
211 | if (ret) { | |
212 | pr_debug("kernel signature verification failed.\n"); | |
213 | goto out; | |
214 | } | |
215 | pr_debug("kernel signature verification successful.\n"); | |
216 | #endif | |
217 | /* It is possible that there no initramfs is being loaded */ | |
218 | if (!(flags & KEXEC_FILE_NO_INITRAMFS)) { | |
b804defe MZ |
219 | ret = kernel_read_file_from_fd(initrd_fd, &image->initrd_buf, |
220 | &size, INT_MAX, | |
221 | READING_KEXEC_INITRAMFS); | |
a43cac0d DY |
222 | if (ret) |
223 | goto out; | |
b804defe | 224 | image->initrd_buf_len = size; |
a43cac0d DY |
225 | } |
226 | ||
227 | if (cmdline_len) { | |
a9bd8dfa AV |
228 | image->cmdline_buf = memdup_user(cmdline_ptr, cmdline_len); |
229 | if (IS_ERR(image->cmdline_buf)) { | |
230 | ret = PTR_ERR(image->cmdline_buf); | |
231 | image->cmdline_buf = NULL; | |
a43cac0d DY |
232 | goto out; |
233 | } | |
234 | ||
235 | image->cmdline_buf_len = cmdline_len; | |
236 | ||
237 | /* command line should be a string with last byte null */ | |
238 | if (image->cmdline_buf[cmdline_len - 1] != '\0') { | |
239 | ret = -EINVAL; | |
240 | goto out; | |
241 | } | |
242 | } | |
243 | ||
244 | /* Call arch image load handlers */ | |
245 | ldata = arch_kexec_kernel_image_load(image); | |
246 | ||
247 | if (IS_ERR(ldata)) { | |
248 | ret = PTR_ERR(ldata); | |
249 | goto out; | |
250 | } | |
251 | ||
252 | image->image_loader_data = ldata; | |
253 | out: | |
254 | /* In case of error, free up all allocated memory in this function */ | |
255 | if (ret) | |
256 | kimage_file_post_load_cleanup(image); | |
257 | return ret; | |
258 | } | |
259 | ||
260 | static int | |
261 | kimage_file_alloc_init(struct kimage **rimage, int kernel_fd, | |
262 | int initrd_fd, const char __user *cmdline_ptr, | |
263 | unsigned long cmdline_len, unsigned long flags) | |
264 | { | |
265 | int ret; | |
266 | struct kimage *image; | |
267 | bool kexec_on_panic = flags & KEXEC_FILE_ON_CRASH; | |
268 | ||
269 | image = do_kimage_alloc_init(); | |
270 | if (!image) | |
271 | return -ENOMEM; | |
272 | ||
273 | image->file_mode = 1; | |
274 | ||
275 | if (kexec_on_panic) { | |
276 | /* Enable special crash kernel control page alloc policy. */ | |
277 | image->control_page = crashk_res.start; | |
278 | image->type = KEXEC_TYPE_CRASH; | |
279 | } | |
280 | ||
281 | ret = kimage_file_prepare_segments(image, kernel_fd, initrd_fd, | |
282 | cmdline_ptr, cmdline_len, flags); | |
283 | if (ret) | |
284 | goto out_free_image; | |
285 | ||
286 | ret = sanity_check_segment_list(image); | |
287 | if (ret) | |
288 | goto out_free_post_load_bufs; | |
289 | ||
290 | ret = -ENOMEM; | |
291 | image->control_code_page = kimage_alloc_control_pages(image, | |
292 | get_order(KEXEC_CONTROL_PAGE_SIZE)); | |
293 | if (!image->control_code_page) { | |
294 | pr_err("Could not allocate control_code_buffer\n"); | |
295 | goto out_free_post_load_bufs; | |
296 | } | |
297 | ||
298 | if (!kexec_on_panic) { | |
299 | image->swap_page = kimage_alloc_control_pages(image, 0); | |
300 | if (!image->swap_page) { | |
301 | pr_err("Could not allocate swap buffer\n"); | |
302 | goto out_free_control_pages; | |
303 | } | |
304 | } | |
305 | ||
306 | *rimage = image; | |
307 | return 0; | |
308 | out_free_control_pages: | |
309 | kimage_free_page_list(&image->control_pages); | |
310 | out_free_post_load_bufs: | |
311 | kimage_file_post_load_cleanup(image); | |
312 | out_free_image: | |
313 | kfree(image); | |
314 | return ret; | |
315 | } | |
316 | ||
317 | SYSCALL_DEFINE5(kexec_file_load, int, kernel_fd, int, initrd_fd, | |
318 | unsigned long, cmdline_len, const char __user *, cmdline_ptr, | |
319 | unsigned long, flags) | |
320 | { | |
321 | int ret = 0, i; | |
322 | struct kimage **dest_image, *image; | |
323 | ||
324 | /* We only trust the superuser with rebooting the system. */ | |
325 | if (!capable(CAP_SYS_BOOT) || kexec_load_disabled) | |
326 | return -EPERM; | |
327 | ||
328 | /* Make sure we have a legal set of flags */ | |
329 | if (flags != (flags & KEXEC_FILE_FLAGS)) | |
330 | return -EINVAL; | |
331 | ||
332 | image = NULL; | |
333 | ||
334 | if (!mutex_trylock(&kexec_mutex)) | |
335 | return -EBUSY; | |
336 | ||
337 | dest_image = &kexec_image; | |
9b492cf5 | 338 | if (flags & KEXEC_FILE_ON_CRASH) { |
a43cac0d | 339 | dest_image = &kexec_crash_image; |
9b492cf5 XP |
340 | if (kexec_crash_image) |
341 | arch_kexec_unprotect_crashkres(); | |
342 | } | |
a43cac0d DY |
343 | |
344 | if (flags & KEXEC_FILE_UNLOAD) | |
345 | goto exchange; | |
346 | ||
347 | /* | |
348 | * In case of crash, new kernel gets loaded in reserved region. It is | |
349 | * same memory where old crash kernel might be loaded. Free any | |
350 | * current crash dump kernel before we corrupt it. | |
351 | */ | |
352 | if (flags & KEXEC_FILE_ON_CRASH) | |
353 | kimage_free(xchg(&kexec_crash_image, NULL)); | |
354 | ||
355 | ret = kimage_file_alloc_init(&image, kernel_fd, initrd_fd, cmdline_ptr, | |
356 | cmdline_len, flags); | |
357 | if (ret) | |
358 | goto out; | |
359 | ||
360 | ret = machine_kexec_prepare(image); | |
361 | if (ret) | |
362 | goto out; | |
363 | ||
1229384f XP |
364 | /* |
365 | * Some architecture(like S390) may touch the crash memory before | |
366 | * machine_kexec_prepare(), we must copy vmcoreinfo data after it. | |
367 | */ | |
368 | ret = kimage_crash_copy_vmcoreinfo(image); | |
369 | if (ret) | |
370 | goto out; | |
371 | ||
a43cac0d DY |
372 | ret = kexec_calculate_store_digests(image); |
373 | if (ret) | |
374 | goto out; | |
375 | ||
376 | for (i = 0; i < image->nr_segments; i++) { | |
377 | struct kexec_segment *ksegment; | |
378 | ||
379 | ksegment = &image->segment[i]; | |
380 | pr_debug("Loading segment %d: buf=0x%p bufsz=0x%zx mem=0x%lx memsz=0x%zx\n", | |
381 | i, ksegment->buf, ksegment->bufsz, ksegment->mem, | |
382 | ksegment->memsz); | |
383 | ||
384 | ret = kimage_load_segment(image, &image->segment[i]); | |
385 | if (ret) | |
386 | goto out; | |
387 | } | |
388 | ||
389 | kimage_terminate(image); | |
390 | ||
391 | /* | |
392 | * Free up any temporary buffers allocated which are not needed | |
393 | * after image has been loaded | |
394 | */ | |
395 | kimage_file_post_load_cleanup(image); | |
396 | exchange: | |
397 | image = xchg(dest_image, image); | |
398 | out: | |
9b492cf5 XP |
399 | if ((flags & KEXEC_FILE_ON_CRASH) && kexec_crash_image) |
400 | arch_kexec_protect_crashkres(); | |
401 | ||
a43cac0d DY |
402 | mutex_unlock(&kexec_mutex); |
403 | kimage_free(image); | |
404 | return ret; | |
405 | } | |
406 | ||
407 | static int locate_mem_hole_top_down(unsigned long start, unsigned long end, | |
408 | struct kexec_buf *kbuf) | |
409 | { | |
410 | struct kimage *image = kbuf->image; | |
411 | unsigned long temp_start, temp_end; | |
412 | ||
413 | temp_end = min(end, kbuf->buf_max); | |
414 | temp_start = temp_end - kbuf->memsz; | |
415 | ||
416 | do { | |
417 | /* align down start */ | |
418 | temp_start = temp_start & (~(kbuf->buf_align - 1)); | |
419 | ||
420 | if (temp_start < start || temp_start < kbuf->buf_min) | |
421 | return 0; | |
422 | ||
423 | temp_end = temp_start + kbuf->memsz - 1; | |
424 | ||
425 | /* | |
426 | * Make sure this does not conflict with any of existing | |
427 | * segments | |
428 | */ | |
429 | if (kimage_is_destination_range(image, temp_start, temp_end)) { | |
430 | temp_start = temp_start - PAGE_SIZE; | |
431 | continue; | |
432 | } | |
433 | ||
434 | /* We found a suitable memory range */ | |
435 | break; | |
436 | } while (1); | |
437 | ||
438 | /* If we are here, we found a suitable memory range */ | |
439 | kbuf->mem = temp_start; | |
440 | ||
441 | /* Success, stop navigating through remaining System RAM ranges */ | |
442 | return 1; | |
443 | } | |
444 | ||
445 | static int locate_mem_hole_bottom_up(unsigned long start, unsigned long end, | |
446 | struct kexec_buf *kbuf) | |
447 | { | |
448 | struct kimage *image = kbuf->image; | |
449 | unsigned long temp_start, temp_end; | |
450 | ||
451 | temp_start = max(start, kbuf->buf_min); | |
452 | ||
453 | do { | |
454 | temp_start = ALIGN(temp_start, kbuf->buf_align); | |
455 | temp_end = temp_start + kbuf->memsz - 1; | |
456 | ||
457 | if (temp_end > end || temp_end > kbuf->buf_max) | |
458 | return 0; | |
459 | /* | |
460 | * Make sure this does not conflict with any of existing | |
461 | * segments | |
462 | */ | |
463 | if (kimage_is_destination_range(image, temp_start, temp_end)) { | |
464 | temp_start = temp_start + PAGE_SIZE; | |
465 | continue; | |
466 | } | |
467 | ||
468 | /* We found a suitable memory range */ | |
469 | break; | |
470 | } while (1); | |
471 | ||
472 | /* If we are here, we found a suitable memory range */ | |
473 | kbuf->mem = temp_start; | |
474 | ||
475 | /* Success, stop navigating through remaining System RAM ranges */ | |
476 | return 1; | |
477 | } | |
478 | ||
1d2e733b | 479 | static int locate_mem_hole_callback(struct resource *res, void *arg) |
a43cac0d DY |
480 | { |
481 | struct kexec_buf *kbuf = (struct kexec_buf *)arg; | |
1d2e733b | 482 | u64 start = res->start, end = res->end; |
a43cac0d DY |
483 | unsigned long sz = end - start + 1; |
484 | ||
485 | /* Returning 0 will take to next memory range */ | |
486 | if (sz < kbuf->memsz) | |
487 | return 0; | |
488 | ||
489 | if (end < kbuf->buf_min || start > kbuf->buf_max) | |
490 | return 0; | |
491 | ||
492 | /* | |
493 | * Allocate memory top down with-in ram range. Otherwise bottom up | |
494 | * allocation. | |
495 | */ | |
496 | if (kbuf->top_down) | |
497 | return locate_mem_hole_top_down(start, end, kbuf); | |
498 | return locate_mem_hole_bottom_up(start, end, kbuf); | |
499 | } | |
500 | ||
350e88ba | 501 | #ifdef CONFIG_ARCH_KEEP_MEMBLOCK |
735c2f90 AT |
502 | static int kexec_walk_memblock(struct kexec_buf *kbuf, |
503 | int (*func)(struct resource *, void *)) | |
504 | { | |
505 | int ret = 0; | |
506 | u64 i; | |
507 | phys_addr_t mstart, mend; | |
508 | struct resource res = { }; | |
509 | ||
497e1858 AT |
510 | if (kbuf->image->type == KEXEC_TYPE_CRASH) |
511 | return func(&crashk_res, kbuf); | |
512 | ||
735c2f90 | 513 | if (kbuf->top_down) { |
497e1858 | 514 | for_each_free_mem_range_reverse(i, NUMA_NO_NODE, MEMBLOCK_NONE, |
735c2f90 AT |
515 | &mstart, &mend, NULL) { |
516 | /* | |
517 | * In memblock, end points to the first byte after the | |
518 | * range while in kexec, end points to the last byte | |
519 | * in the range. | |
520 | */ | |
521 | res.start = mstart; | |
522 | res.end = mend - 1; | |
523 | ret = func(&res, kbuf); | |
524 | if (ret) | |
525 | break; | |
526 | } | |
527 | } else { | |
497e1858 AT |
528 | for_each_free_mem_range(i, NUMA_NO_NODE, MEMBLOCK_NONE, |
529 | &mstart, &mend, NULL) { | |
735c2f90 AT |
530 | /* |
531 | * In memblock, end points to the first byte after the | |
532 | * range while in kexec, end points to the last byte | |
533 | * in the range. | |
534 | */ | |
535 | res.start = mstart; | |
536 | res.end = mend - 1; | |
537 | ret = func(&res, kbuf); | |
538 | if (ret) | |
539 | break; | |
540 | } | |
541 | } | |
542 | ||
543 | return ret; | |
544 | } | |
350e88ba MR |
545 | #else |
546 | static int kexec_walk_memblock(struct kexec_buf *kbuf, | |
547 | int (*func)(struct resource *, void *)) | |
548 | { | |
549 | return 0; | |
550 | } | |
735c2f90 AT |
551 | #endif |
552 | ||
60fe3910 | 553 | /** |
735c2f90 | 554 | * kexec_walk_resources - call func(data) on free memory regions |
60fe3910 TJB |
555 | * @kbuf: Context info for the search. Also passed to @func. |
556 | * @func: Function to call for each memory region. | |
557 | * | |
558 | * Return: The memory walk will stop when func returns a non-zero value | |
559 | * and that value will be returned. If all free regions are visited without | |
560 | * func returning non-zero, then zero will be returned. | |
561 | */ | |
735c2f90 AT |
562 | static int kexec_walk_resources(struct kexec_buf *kbuf, |
563 | int (*func)(struct resource *, void *)) | |
60fe3910 TJB |
564 | { |
565 | if (kbuf->image->type == KEXEC_TYPE_CRASH) | |
566 | return walk_iomem_res_desc(crashk_res.desc, | |
567 | IORESOURCE_SYSTEM_RAM | IORESOURCE_BUSY, | |
568 | crashk_res.start, crashk_res.end, | |
569 | kbuf, func); | |
570 | else | |
571 | return walk_system_ram_res(0, ULONG_MAX, kbuf, func); | |
572 | } | |
573 | ||
e2e806f9 TJB |
574 | /** |
575 | * kexec_locate_mem_hole - find free memory for the purgatory or the next kernel | |
576 | * @kbuf: Parameters for the memory search. | |
577 | * | |
578 | * On success, kbuf->mem will have the start address of the memory region found. | |
579 | * | |
580 | * Return: 0 on success, negative errno on error. | |
581 | */ | |
582 | int kexec_locate_mem_hole(struct kexec_buf *kbuf) | |
583 | { | |
584 | int ret; | |
585 | ||
b6664ba4 AT |
586 | /* Arch knows where to place */ |
587 | if (kbuf->mem != KEXEC_BUF_MEM_UNKNOWN) | |
588 | return 0; | |
589 | ||
350e88ba | 590 | if (!IS_ENABLED(CONFIG_ARCH_KEEP_MEMBLOCK)) |
735c2f90 AT |
591 | ret = kexec_walk_resources(kbuf, locate_mem_hole_callback); |
592 | else | |
593 | ret = kexec_walk_memblock(kbuf, locate_mem_hole_callback); | |
e2e806f9 TJB |
594 | |
595 | return ret == 1 ? 0 : -EADDRNOTAVAIL; | |
596 | } | |
597 | ||
ec2b9bfa TJB |
598 | /** |
599 | * kexec_add_buffer - place a buffer in a kexec segment | |
600 | * @kbuf: Buffer contents and memory parameters. | |
601 | * | |
602 | * This function assumes that kexec_mutex is held. | |
603 | * On successful return, @kbuf->mem will have the physical address of | |
604 | * the buffer in memory. | |
605 | * | |
606 | * Return: 0 on success, negative errno on error. | |
a43cac0d | 607 | */ |
ec2b9bfa | 608 | int kexec_add_buffer(struct kexec_buf *kbuf) |
a43cac0d DY |
609 | { |
610 | ||
611 | struct kexec_segment *ksegment; | |
a43cac0d DY |
612 | int ret; |
613 | ||
614 | /* Currently adding segment this way is allowed only in file mode */ | |
ec2b9bfa | 615 | if (!kbuf->image->file_mode) |
a43cac0d DY |
616 | return -EINVAL; |
617 | ||
ec2b9bfa | 618 | if (kbuf->image->nr_segments >= KEXEC_SEGMENT_MAX) |
a43cac0d DY |
619 | return -EINVAL; |
620 | ||
621 | /* | |
622 | * Make sure we are not trying to add buffer after allocating | |
623 | * control pages. All segments need to be placed first before | |
624 | * any control pages are allocated. As control page allocation | |
625 | * logic goes through list of segments to make sure there are | |
626 | * no destination overlaps. | |
627 | */ | |
ec2b9bfa | 628 | if (!list_empty(&kbuf->image->control_pages)) { |
a43cac0d DY |
629 | WARN_ON(1); |
630 | return -EINVAL; | |
631 | } | |
632 | ||
ec2b9bfa TJB |
633 | /* Ensure minimum alignment needed for segments. */ |
634 | kbuf->memsz = ALIGN(kbuf->memsz, PAGE_SIZE); | |
635 | kbuf->buf_align = max(kbuf->buf_align, PAGE_SIZE); | |
a43cac0d DY |
636 | |
637 | /* Walk the RAM ranges and allocate a suitable range for the buffer */ | |
e2e806f9 TJB |
638 | ret = kexec_locate_mem_hole(kbuf); |
639 | if (ret) | |
640 | return ret; | |
a43cac0d DY |
641 | |
642 | /* Found a suitable memory range */ | |
ec2b9bfa | 643 | ksegment = &kbuf->image->segment[kbuf->image->nr_segments]; |
a43cac0d DY |
644 | ksegment->kbuf = kbuf->buffer; |
645 | ksegment->bufsz = kbuf->bufsz; | |
646 | ksegment->mem = kbuf->mem; | |
647 | ksegment->memsz = kbuf->memsz; | |
ec2b9bfa | 648 | kbuf->image->nr_segments++; |
a43cac0d DY |
649 | return 0; |
650 | } | |
651 | ||
652 | /* Calculate and store the digest of segments */ | |
653 | static int kexec_calculate_store_digests(struct kimage *image) | |
654 | { | |
655 | struct crypto_shash *tfm; | |
656 | struct shash_desc *desc; | |
657 | int ret = 0, i, j, zero_buf_sz, sha_region_sz; | |
658 | size_t desc_size, nullsz; | |
659 | char *digest; | |
660 | void *zero_buf; | |
661 | struct kexec_sha_region *sha_regions; | |
662 | struct purgatory_info *pi = &image->purgatory_info; | |
663 | ||
b799a09f AT |
664 | if (!IS_ENABLED(CONFIG_ARCH_HAS_KEXEC_PURGATORY)) |
665 | return 0; | |
666 | ||
a43cac0d DY |
667 | zero_buf = __va(page_to_pfn(ZERO_PAGE(0)) << PAGE_SHIFT); |
668 | zero_buf_sz = PAGE_SIZE; | |
669 | ||
670 | tfm = crypto_alloc_shash("sha256", 0, 0); | |
671 | if (IS_ERR(tfm)) { | |
672 | ret = PTR_ERR(tfm); | |
673 | goto out; | |
674 | } | |
675 | ||
676 | desc_size = crypto_shash_descsize(tfm) + sizeof(*desc); | |
677 | desc = kzalloc(desc_size, GFP_KERNEL); | |
678 | if (!desc) { | |
679 | ret = -ENOMEM; | |
680 | goto out_free_tfm; | |
681 | } | |
682 | ||
683 | sha_region_sz = KEXEC_SEGMENT_MAX * sizeof(struct kexec_sha_region); | |
684 | sha_regions = vzalloc(sha_region_sz); | |
685 | if (!sha_regions) | |
686 | goto out_free_desc; | |
687 | ||
688 | desc->tfm = tfm; | |
a43cac0d DY |
689 | |
690 | ret = crypto_shash_init(desc); | |
691 | if (ret < 0) | |
692 | goto out_free_sha_regions; | |
693 | ||
694 | digest = kzalloc(SHA256_DIGEST_SIZE, GFP_KERNEL); | |
695 | if (!digest) { | |
696 | ret = -ENOMEM; | |
697 | goto out_free_sha_regions; | |
698 | } | |
699 | ||
700 | for (j = i = 0; i < image->nr_segments; i++) { | |
701 | struct kexec_segment *ksegment; | |
702 | ||
703 | ksegment = &image->segment[i]; | |
704 | /* | |
705 | * Skip purgatory as it will be modified once we put digest | |
706 | * info in purgatory. | |
707 | */ | |
708 | if (ksegment->kbuf == pi->purgatory_buf) | |
709 | continue; | |
710 | ||
711 | ret = crypto_shash_update(desc, ksegment->kbuf, | |
712 | ksegment->bufsz); | |
713 | if (ret) | |
714 | break; | |
715 | ||
716 | /* | |
717 | * Assume rest of the buffer is filled with zero and | |
718 | * update digest accordingly. | |
719 | */ | |
720 | nullsz = ksegment->memsz - ksegment->bufsz; | |
721 | while (nullsz) { | |
722 | unsigned long bytes = nullsz; | |
723 | ||
724 | if (bytes > zero_buf_sz) | |
725 | bytes = zero_buf_sz; | |
726 | ret = crypto_shash_update(desc, zero_buf, bytes); | |
727 | if (ret) | |
728 | break; | |
729 | nullsz -= bytes; | |
730 | } | |
731 | ||
732 | if (ret) | |
733 | break; | |
734 | ||
735 | sha_regions[j].start = ksegment->mem; | |
736 | sha_regions[j].len = ksegment->memsz; | |
737 | j++; | |
738 | } | |
739 | ||
740 | if (!ret) { | |
741 | ret = crypto_shash_final(desc, digest); | |
742 | if (ret) | |
743 | goto out_free_digest; | |
40c50c1f TG |
744 | ret = kexec_purgatory_get_set_symbol(image, "purgatory_sha_regions", |
745 | sha_regions, sha_region_sz, 0); | |
a43cac0d DY |
746 | if (ret) |
747 | goto out_free_digest; | |
748 | ||
40c50c1f TG |
749 | ret = kexec_purgatory_get_set_symbol(image, "purgatory_sha256_digest", |
750 | digest, SHA256_DIGEST_SIZE, 0); | |
a43cac0d DY |
751 | if (ret) |
752 | goto out_free_digest; | |
753 | } | |
754 | ||
755 | out_free_digest: | |
756 | kfree(digest); | |
757 | out_free_sha_regions: | |
758 | vfree(sha_regions); | |
759 | out_free_desc: | |
760 | kfree(desc); | |
761 | out_free_tfm: | |
762 | kfree(tfm); | |
763 | out: | |
764 | return ret; | |
765 | } | |
766 | ||
b799a09f | 767 | #ifdef CONFIG_ARCH_HAS_KEXEC_PURGATORY |
93045705 PR |
768 | /* |
769 | * kexec_purgatory_setup_kbuf - prepare buffer to load purgatory. | |
770 | * @pi: Purgatory to be loaded. | |
771 | * @kbuf: Buffer to setup. | |
772 | * | |
773 | * Allocates the memory needed for the buffer. Caller is responsible to free | |
774 | * the memory after use. | |
775 | * | |
776 | * Return: 0 on success, negative errno on error. | |
777 | */ | |
778 | static int kexec_purgatory_setup_kbuf(struct purgatory_info *pi, | |
779 | struct kexec_buf *kbuf) | |
a43cac0d | 780 | { |
93045705 PR |
781 | const Elf_Shdr *sechdrs; |
782 | unsigned long bss_align; | |
783 | unsigned long bss_sz; | |
784 | unsigned long align; | |
785 | int i, ret; | |
a43cac0d | 786 | |
93045705 | 787 | sechdrs = (void *)pi->ehdr + pi->ehdr->e_shoff; |
3be3f61d PR |
788 | kbuf->buf_align = bss_align = 1; |
789 | kbuf->bufsz = bss_sz = 0; | |
93045705 PR |
790 | |
791 | for (i = 0; i < pi->ehdr->e_shnum; i++) { | |
792 | if (!(sechdrs[i].sh_flags & SHF_ALLOC)) | |
793 | continue; | |
794 | ||
795 | align = sechdrs[i].sh_addralign; | |
796 | if (sechdrs[i].sh_type != SHT_NOBITS) { | |
797 | if (kbuf->buf_align < align) | |
798 | kbuf->buf_align = align; | |
799 | kbuf->bufsz = ALIGN(kbuf->bufsz, align); | |
800 | kbuf->bufsz += sechdrs[i].sh_size; | |
801 | } else { | |
802 | if (bss_align < align) | |
803 | bss_align = align; | |
804 | bss_sz = ALIGN(bss_sz, align); | |
805 | bss_sz += sechdrs[i].sh_size; | |
806 | } | |
807 | } | |
808 | kbuf->bufsz = ALIGN(kbuf->bufsz, bss_align); | |
809 | kbuf->memsz = kbuf->bufsz + bss_sz; | |
810 | if (kbuf->buf_align < bss_align) | |
811 | kbuf->buf_align = bss_align; | |
812 | ||
813 | kbuf->buffer = vzalloc(kbuf->bufsz); | |
814 | if (!kbuf->buffer) | |
815 | return -ENOMEM; | |
816 | pi->purgatory_buf = kbuf->buffer; | |
817 | ||
818 | ret = kexec_add_buffer(kbuf); | |
819 | if (ret) | |
820 | goto out; | |
93045705 PR |
821 | |
822 | return 0; | |
823 | out: | |
824 | vfree(pi->purgatory_buf); | |
825 | pi->purgatory_buf = NULL; | |
826 | return ret; | |
827 | } | |
828 | ||
829 | /* | |
830 | * kexec_purgatory_setup_sechdrs - prepares the pi->sechdrs buffer. | |
831 | * @pi: Purgatory to be loaded. | |
832 | * @kbuf: Buffer prepared to store purgatory. | |
833 | * | |
834 | * Allocates the memory needed for the buffer. Caller is responsible to free | |
835 | * the memory after use. | |
836 | * | |
837 | * Return: 0 on success, negative errno on error. | |
838 | */ | |
839 | static int kexec_purgatory_setup_sechdrs(struct purgatory_info *pi, | |
840 | struct kexec_buf *kbuf) | |
841 | { | |
93045705 PR |
842 | unsigned long bss_addr; |
843 | unsigned long offset; | |
93045705 | 844 | Elf_Shdr *sechdrs; |
93045705 | 845 | int i; |
a43cac0d | 846 | |
8da0b724 PR |
847 | /* |
848 | * The section headers in kexec_purgatory are read-only. In order to | |
849 | * have them modifiable make a temporary copy. | |
850 | */ | |
fad953ce | 851 | sechdrs = vzalloc(array_size(sizeof(Elf_Shdr), pi->ehdr->e_shnum)); |
a43cac0d DY |
852 | if (!sechdrs) |
853 | return -ENOMEM; | |
93045705 PR |
854 | memcpy(sechdrs, (void *)pi->ehdr + pi->ehdr->e_shoff, |
855 | pi->ehdr->e_shnum * sizeof(Elf_Shdr)); | |
856 | pi->sechdrs = sechdrs; | |
a43cac0d | 857 | |
620f697c PR |
858 | offset = 0; |
859 | bss_addr = kbuf->mem + kbuf->bufsz; | |
f1b1cca3 | 860 | kbuf->image->start = pi->ehdr->e_entry; |
a43cac0d DY |
861 | |
862 | for (i = 0; i < pi->ehdr->e_shnum; i++) { | |
93045705 | 863 | unsigned long align; |
620f697c | 864 | void *src, *dst; |
93045705 | 865 | |
a43cac0d DY |
866 | if (!(sechdrs[i].sh_flags & SHF_ALLOC)) |
867 | continue; | |
868 | ||
869 | align = sechdrs[i].sh_addralign; | |
f1b1cca3 | 870 | if (sechdrs[i].sh_type == SHT_NOBITS) { |
a43cac0d DY |
871 | bss_addr = ALIGN(bss_addr, align); |
872 | sechdrs[i].sh_addr = bss_addr; | |
873 | bss_addr += sechdrs[i].sh_size; | |
f1b1cca3 PR |
874 | continue; |
875 | } | |
876 | ||
620f697c | 877 | offset = ALIGN(offset, align); |
f1b1cca3 PR |
878 | if (sechdrs[i].sh_flags & SHF_EXECINSTR && |
879 | pi->ehdr->e_entry >= sechdrs[i].sh_addr && | |
880 | pi->ehdr->e_entry < (sechdrs[i].sh_addr | |
881 | + sechdrs[i].sh_size)) { | |
882 | kbuf->image->start -= sechdrs[i].sh_addr; | |
620f697c | 883 | kbuf->image->start += kbuf->mem + offset; |
a43cac0d | 884 | } |
a43cac0d | 885 | |
8da0b724 | 886 | src = (void *)pi->ehdr + sechdrs[i].sh_offset; |
620f697c PR |
887 | dst = pi->purgatory_buf + offset; |
888 | memcpy(dst, src, sechdrs[i].sh_size); | |
889 | ||
890 | sechdrs[i].sh_addr = kbuf->mem + offset; | |
8da0b724 | 891 | sechdrs[i].sh_offset = offset; |
620f697c | 892 | offset += sechdrs[i].sh_size; |
f1b1cca3 | 893 | } |
a43cac0d | 894 | |
93045705 | 895 | return 0; |
a43cac0d DY |
896 | } |
897 | ||
898 | static int kexec_apply_relocations(struct kimage *image) | |
899 | { | |
900 | int i, ret; | |
901 | struct purgatory_info *pi = &image->purgatory_info; | |
8aec395b PR |
902 | const Elf_Shdr *sechdrs; |
903 | ||
904 | sechdrs = (void *)pi->ehdr + pi->ehdr->e_shoff; | |
a43cac0d | 905 | |
a43cac0d | 906 | for (i = 0; i < pi->ehdr->e_shnum; i++) { |
8aec395b PR |
907 | const Elf_Shdr *relsec; |
908 | const Elf_Shdr *symtab; | |
909 | Elf_Shdr *section; | |
910 | ||
911 | relsec = sechdrs + i; | |
a43cac0d | 912 | |
8aec395b PR |
913 | if (relsec->sh_type != SHT_RELA && |
914 | relsec->sh_type != SHT_REL) | |
a43cac0d DY |
915 | continue; |
916 | ||
917 | /* | |
918 | * For section of type SHT_RELA/SHT_REL, | |
919 | * ->sh_link contains section header index of associated | |
920 | * symbol table. And ->sh_info contains section header | |
921 | * index of section to which relocations apply. | |
922 | */ | |
8aec395b PR |
923 | if (relsec->sh_info >= pi->ehdr->e_shnum || |
924 | relsec->sh_link >= pi->ehdr->e_shnum) | |
a43cac0d DY |
925 | return -ENOEXEC; |
926 | ||
8aec395b PR |
927 | section = pi->sechdrs + relsec->sh_info; |
928 | symtab = sechdrs + relsec->sh_link; | |
a43cac0d DY |
929 | |
930 | if (!(section->sh_flags & SHF_ALLOC)) | |
931 | continue; | |
932 | ||
933 | /* | |
934 | * symtab->sh_link contain section header index of associated | |
935 | * string table. | |
936 | */ | |
937 | if (symtab->sh_link >= pi->ehdr->e_shnum) | |
938 | /* Invalid section number? */ | |
939 | continue; | |
940 | ||
941 | /* | |
942 | * Respective architecture needs to provide support for applying | |
943 | * relocations of type SHT_RELA/SHT_REL. | |
944 | */ | |
8aec395b PR |
945 | if (relsec->sh_type == SHT_RELA) |
946 | ret = arch_kexec_apply_relocations_add(pi, section, | |
947 | relsec, symtab); | |
948 | else if (relsec->sh_type == SHT_REL) | |
949 | ret = arch_kexec_apply_relocations(pi, section, | |
950 | relsec, symtab); | |
a43cac0d DY |
951 | if (ret) |
952 | return ret; | |
953 | } | |
954 | ||
955 | return 0; | |
956 | } | |
957 | ||
3be3f61d PR |
958 | /* |
959 | * kexec_load_purgatory - Load and relocate the purgatory object. | |
960 | * @image: Image to add the purgatory to. | |
961 | * @kbuf: Memory parameters to use. | |
962 | * | |
963 | * Allocates the memory needed for image->purgatory_info.sechdrs and | |
964 | * image->purgatory_info.purgatory_buf/kbuf->buffer. Caller is responsible | |
965 | * to free the memory after use. | |
966 | * | |
967 | * Return: 0 on success, negative errno on error. | |
968 | */ | |
969 | int kexec_load_purgatory(struct kimage *image, struct kexec_buf *kbuf) | |
a43cac0d DY |
970 | { |
971 | struct purgatory_info *pi = &image->purgatory_info; | |
972 | int ret; | |
973 | ||
974 | if (kexec_purgatory_size <= 0) | |
975 | return -EINVAL; | |
976 | ||
65c225d3 | 977 | pi->ehdr = (const Elf_Ehdr *)kexec_purgatory; |
a43cac0d | 978 | |
3be3f61d | 979 | ret = kexec_purgatory_setup_kbuf(pi, kbuf); |
a43cac0d DY |
980 | if (ret) |
981 | return ret; | |
982 | ||
3be3f61d | 983 | ret = kexec_purgatory_setup_sechdrs(pi, kbuf); |
93045705 PR |
984 | if (ret) |
985 | goto out_free_kbuf; | |
986 | ||
a43cac0d DY |
987 | ret = kexec_apply_relocations(image); |
988 | if (ret) | |
989 | goto out; | |
990 | ||
a43cac0d DY |
991 | return 0; |
992 | out: | |
993 | vfree(pi->sechdrs); | |
070c43ee | 994 | pi->sechdrs = NULL; |
93045705 | 995 | out_free_kbuf: |
a43cac0d | 996 | vfree(pi->purgatory_buf); |
070c43ee | 997 | pi->purgatory_buf = NULL; |
a43cac0d DY |
998 | return ret; |
999 | } | |
1000 | ||
961d921a PR |
1001 | /* |
1002 | * kexec_purgatory_find_symbol - find a symbol in the purgatory | |
1003 | * @pi: Purgatory to search in. | |
1004 | * @name: Name of the symbol. | |
1005 | * | |
1006 | * Return: pointer to symbol in read-only symtab on success, NULL on error. | |
1007 | */ | |
1008 | static const Elf_Sym *kexec_purgatory_find_symbol(struct purgatory_info *pi, | |
1009 | const char *name) | |
a43cac0d | 1010 | { |
961d921a | 1011 | const Elf_Shdr *sechdrs; |
65c225d3 | 1012 | const Elf_Ehdr *ehdr; |
961d921a | 1013 | const Elf_Sym *syms; |
a43cac0d | 1014 | const char *strtab; |
961d921a | 1015 | int i, k; |
a43cac0d | 1016 | |
961d921a | 1017 | if (!pi->ehdr) |
a43cac0d DY |
1018 | return NULL; |
1019 | ||
a43cac0d | 1020 | ehdr = pi->ehdr; |
961d921a | 1021 | sechdrs = (void *)ehdr + ehdr->e_shoff; |
a43cac0d DY |
1022 | |
1023 | for (i = 0; i < ehdr->e_shnum; i++) { | |
1024 | if (sechdrs[i].sh_type != SHT_SYMTAB) | |
1025 | continue; | |
1026 | ||
1027 | if (sechdrs[i].sh_link >= ehdr->e_shnum) | |
1028 | /* Invalid strtab section number */ | |
1029 | continue; | |
961d921a PR |
1030 | strtab = (void *)ehdr + sechdrs[sechdrs[i].sh_link].sh_offset; |
1031 | syms = (void *)ehdr + sechdrs[i].sh_offset; | |
a43cac0d DY |
1032 | |
1033 | /* Go through symbols for a match */ | |
1034 | for (k = 0; k < sechdrs[i].sh_size/sizeof(Elf_Sym); k++) { | |
1035 | if (ELF_ST_BIND(syms[k].st_info) != STB_GLOBAL) | |
1036 | continue; | |
1037 | ||
1038 | if (strcmp(strtab + syms[k].st_name, name) != 0) | |
1039 | continue; | |
1040 | ||
1041 | if (syms[k].st_shndx == SHN_UNDEF || | |
1042 | syms[k].st_shndx >= ehdr->e_shnum) { | |
1043 | pr_debug("Symbol: %s has bad section index %d.\n", | |
1044 | name, syms[k].st_shndx); | |
1045 | return NULL; | |
1046 | } | |
1047 | ||
1048 | /* Found the symbol we are looking for */ | |
1049 | return &syms[k]; | |
1050 | } | |
1051 | } | |
1052 | ||
1053 | return NULL; | |
1054 | } | |
1055 | ||
1056 | void *kexec_purgatory_get_symbol_addr(struct kimage *image, const char *name) | |
1057 | { | |
1058 | struct purgatory_info *pi = &image->purgatory_info; | |
961d921a | 1059 | const Elf_Sym *sym; |
a43cac0d DY |
1060 | Elf_Shdr *sechdr; |
1061 | ||
1062 | sym = kexec_purgatory_find_symbol(pi, name); | |
1063 | if (!sym) | |
1064 | return ERR_PTR(-EINVAL); | |
1065 | ||
1066 | sechdr = &pi->sechdrs[sym->st_shndx]; | |
1067 | ||
1068 | /* | |
1069 | * Returns the address where symbol will finally be loaded after | |
1070 | * kexec_load_segment() | |
1071 | */ | |
1072 | return (void *)(sechdr->sh_addr + sym->st_value); | |
1073 | } | |
1074 | ||
1075 | /* | |
1076 | * Get or set value of a symbol. If "get_value" is true, symbol value is | |
1077 | * returned in buf otherwise symbol value is set based on value in buf. | |
1078 | */ | |
1079 | int kexec_purgatory_get_set_symbol(struct kimage *image, const char *name, | |
1080 | void *buf, unsigned int size, bool get_value) | |
1081 | { | |
a43cac0d | 1082 | struct purgatory_info *pi = &image->purgatory_info; |
961d921a PR |
1083 | const Elf_Sym *sym; |
1084 | Elf_Shdr *sec; | |
a43cac0d DY |
1085 | char *sym_buf; |
1086 | ||
1087 | sym = kexec_purgatory_find_symbol(pi, name); | |
1088 | if (!sym) | |
1089 | return -EINVAL; | |
1090 | ||
1091 | if (sym->st_size != size) { | |
1092 | pr_err("symbol %s size mismatch: expected %lu actual %u\n", | |
1093 | name, (unsigned long)sym->st_size, size); | |
1094 | return -EINVAL; | |
1095 | } | |
1096 | ||
961d921a | 1097 | sec = pi->sechdrs + sym->st_shndx; |
a43cac0d | 1098 | |
961d921a | 1099 | if (sec->sh_type == SHT_NOBITS) { |
a43cac0d DY |
1100 | pr_err("symbol %s is in a bss section. Cannot %s\n", name, |
1101 | get_value ? "get" : "set"); | |
1102 | return -EINVAL; | |
1103 | } | |
1104 | ||
8da0b724 | 1105 | sym_buf = (char *)pi->purgatory_buf + sec->sh_offset + sym->st_value; |
a43cac0d DY |
1106 | |
1107 | if (get_value) | |
1108 | memcpy((void *)buf, sym_buf, size); | |
1109 | else | |
1110 | memcpy((void *)sym_buf, buf, size); | |
1111 | ||
1112 | return 0; | |
1113 | } | |
b799a09f | 1114 | #endif /* CONFIG_ARCH_HAS_KEXEC_PURGATORY */ |
babac4a8 AT |
1115 | |
1116 | int crash_exclude_mem_range(struct crash_mem *mem, | |
1117 | unsigned long long mstart, unsigned long long mend) | |
1118 | { | |
1119 | int i, j; | |
1120 | unsigned long long start, end; | |
1121 | struct crash_mem_range temp_range = {0, 0}; | |
1122 | ||
1123 | for (i = 0; i < mem->nr_ranges; i++) { | |
1124 | start = mem->ranges[i].start; | |
1125 | end = mem->ranges[i].end; | |
1126 | ||
1127 | if (mstart > end || mend < start) | |
1128 | continue; | |
1129 | ||
1130 | /* Truncate any area outside of range */ | |
1131 | if (mstart < start) | |
1132 | mstart = start; | |
1133 | if (mend > end) | |
1134 | mend = end; | |
1135 | ||
1136 | /* Found completely overlapping range */ | |
1137 | if (mstart == start && mend == end) { | |
1138 | mem->ranges[i].start = 0; | |
1139 | mem->ranges[i].end = 0; | |
1140 | if (i < mem->nr_ranges - 1) { | |
1141 | /* Shift rest of the ranges to left */ | |
1142 | for (j = i; j < mem->nr_ranges - 1; j++) { | |
1143 | mem->ranges[j].start = | |
1144 | mem->ranges[j+1].start; | |
1145 | mem->ranges[j].end = | |
1146 | mem->ranges[j+1].end; | |
1147 | } | |
1148 | } | |
1149 | mem->nr_ranges--; | |
1150 | return 0; | |
1151 | } | |
1152 | ||
1153 | if (mstart > start && mend < end) { | |
1154 | /* Split original range */ | |
1155 | mem->ranges[i].end = mstart - 1; | |
1156 | temp_range.start = mend + 1; | |
1157 | temp_range.end = end; | |
1158 | } else if (mstart != start) | |
1159 | mem->ranges[i].end = mstart - 1; | |
1160 | else | |
1161 | mem->ranges[i].start = mend + 1; | |
1162 | break; | |
1163 | } | |
1164 | ||
1165 | /* If a split happened, add the split to array */ | |
1166 | if (!temp_range.end) | |
1167 | return 0; | |
1168 | ||
1169 | /* Split happened */ | |
1170 | if (i == mem->max_nr_ranges - 1) | |
1171 | return -ENOMEM; | |
1172 | ||
1173 | /* Location where new range should go */ | |
1174 | j = i + 1; | |
1175 | if (j < mem->nr_ranges) { | |
1176 | /* Move over all ranges one slot towards the end */ | |
1177 | for (i = mem->nr_ranges - 1; i >= j; i--) | |
1178 | mem->ranges[i + 1] = mem->ranges[i]; | |
1179 | } | |
1180 | ||
1181 | mem->ranges[j].start = temp_range.start; | |
1182 | mem->ranges[j].end = temp_range.end; | |
1183 | mem->nr_ranges++; | |
1184 | return 0; | |
1185 | } | |
1186 | ||
1187 | int crash_prepare_elf64_headers(struct crash_mem *mem, int kernel_map, | |
1188 | void **addr, unsigned long *sz) | |
1189 | { | |
1190 | Elf64_Ehdr *ehdr; | |
1191 | Elf64_Phdr *phdr; | |
1192 | unsigned long nr_cpus = num_possible_cpus(), nr_phdr, elf_sz; | |
1193 | unsigned char *buf; | |
1194 | unsigned int cpu, i; | |
1195 | unsigned long long notes_addr; | |
1196 | unsigned long mstart, mend; | |
1197 | ||
1198 | /* extra phdr for vmcoreinfo elf note */ | |
1199 | nr_phdr = nr_cpus + 1; | |
1200 | nr_phdr += mem->nr_ranges; | |
1201 | ||
1202 | /* | |
1203 | * kexec-tools creates an extra PT_LOAD phdr for kernel text mapping | |
1204 | * area (for example, ffffffff80000000 - ffffffffa0000000 on x86_64). | |
1205 | * I think this is required by tools like gdb. So same physical | |
1206 | * memory will be mapped in two elf headers. One will contain kernel | |
1207 | * text virtual addresses and other will have __va(physical) addresses. | |
1208 | */ | |
1209 | ||
1210 | nr_phdr++; | |
1211 | elf_sz = sizeof(Elf64_Ehdr) + nr_phdr * sizeof(Elf64_Phdr); | |
1212 | elf_sz = ALIGN(elf_sz, ELF_CORE_HEADER_ALIGN); | |
1213 | ||
1214 | buf = vzalloc(elf_sz); | |
1215 | if (!buf) | |
1216 | return -ENOMEM; | |
1217 | ||
1218 | ehdr = (Elf64_Ehdr *)buf; | |
1219 | phdr = (Elf64_Phdr *)(ehdr + 1); | |
1220 | memcpy(ehdr->e_ident, ELFMAG, SELFMAG); | |
1221 | ehdr->e_ident[EI_CLASS] = ELFCLASS64; | |
1222 | ehdr->e_ident[EI_DATA] = ELFDATA2LSB; | |
1223 | ehdr->e_ident[EI_VERSION] = EV_CURRENT; | |
1224 | ehdr->e_ident[EI_OSABI] = ELF_OSABI; | |
1225 | memset(ehdr->e_ident + EI_PAD, 0, EI_NIDENT - EI_PAD); | |
1226 | ehdr->e_type = ET_CORE; | |
1227 | ehdr->e_machine = ELF_ARCH; | |
1228 | ehdr->e_version = EV_CURRENT; | |
1229 | ehdr->e_phoff = sizeof(Elf64_Ehdr); | |
1230 | ehdr->e_ehsize = sizeof(Elf64_Ehdr); | |
1231 | ehdr->e_phentsize = sizeof(Elf64_Phdr); | |
1232 | ||
1233 | /* Prepare one phdr of type PT_NOTE for each present cpu */ | |
1234 | for_each_present_cpu(cpu) { | |
1235 | phdr->p_type = PT_NOTE; | |
1236 | notes_addr = per_cpu_ptr_to_phys(per_cpu_ptr(crash_notes, cpu)); | |
1237 | phdr->p_offset = phdr->p_paddr = notes_addr; | |
1238 | phdr->p_filesz = phdr->p_memsz = sizeof(note_buf_t); | |
1239 | (ehdr->e_phnum)++; | |
1240 | phdr++; | |
1241 | } | |
1242 | ||
1243 | /* Prepare one PT_NOTE header for vmcoreinfo */ | |
1244 | phdr->p_type = PT_NOTE; | |
1245 | phdr->p_offset = phdr->p_paddr = paddr_vmcoreinfo_note(); | |
1246 | phdr->p_filesz = phdr->p_memsz = VMCOREINFO_NOTE_SIZE; | |
1247 | (ehdr->e_phnum)++; | |
1248 | phdr++; | |
1249 | ||
1250 | /* Prepare PT_LOAD type program header for kernel text region */ | |
1251 | if (kernel_map) { | |
1252 | phdr->p_type = PT_LOAD; | |
1253 | phdr->p_flags = PF_R|PF_W|PF_X; | |
1254 | phdr->p_vaddr = (Elf64_Addr)_text; | |
1255 | phdr->p_filesz = phdr->p_memsz = _end - _text; | |
1256 | phdr->p_offset = phdr->p_paddr = __pa_symbol(_text); | |
1257 | ehdr->e_phnum++; | |
1258 | phdr++; | |
1259 | } | |
1260 | ||
1261 | /* Go through all the ranges in mem->ranges[] and prepare phdr */ | |
1262 | for (i = 0; i < mem->nr_ranges; i++) { | |
1263 | mstart = mem->ranges[i].start; | |
1264 | mend = mem->ranges[i].end; | |
1265 | ||
1266 | phdr->p_type = PT_LOAD; | |
1267 | phdr->p_flags = PF_R|PF_W|PF_X; | |
1268 | phdr->p_offset = mstart; | |
1269 | ||
1270 | phdr->p_paddr = mstart; | |
1271 | phdr->p_vaddr = (unsigned long long) __va(mstart); | |
1272 | phdr->p_filesz = phdr->p_memsz = mend - mstart + 1; | |
1273 | phdr->p_align = 0; | |
1274 | ehdr->e_phnum++; | |
1275 | phdr++; | |
1276 | pr_debug("Crash PT_LOAD elf header. phdr=%p vaddr=0x%llx, paddr=0x%llx, sz=0x%llx e_phnum=%d p_offset=0x%llx\n", | |
1277 | phdr, phdr->p_vaddr, phdr->p_paddr, phdr->p_filesz, | |
1278 | ehdr->e_phnum, phdr->p_offset); | |
1279 | } | |
1280 | ||
1281 | *addr = buf; | |
1282 | *sz = elf_sz; | |
1283 | return 0; | |
1284 | } |