Commit | Line | Data |
---|---|---|
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 | 22 | #include <crypto/hash.h> |
a24d22b2 | 23 | #include <crypto/sha2.h> |
babac4a8 AT |
24 | #include <linux/elf.h> |
25 | #include <linux/elfcore.h> | |
26 | #include <linux/kernel.h> | |
b89999d0 | 27 | #include <linux/kernel_read_file.h> |
a43cac0d DY |
28 | #include <linux/syscalls.h> |
29 | #include <linux/vmalloc.h> | |
30 | #include "kexec_internal.h" | |
31 | ||
a43cac0d DY |
32 | static int kexec_calculate_store_digests(struct kimage *image); |
33 | ||
9ec4ecef AT |
34 | /* |
35 | * Currently this is the only default function that is exported as some | |
36 | * architectures need it to do additional handlings. | |
37 | * In the future, other default functions may be exported too if required. | |
38 | */ | |
39 | int kexec_image_probe_default(struct kimage *image, void *buf, | |
40 | unsigned long buf_len) | |
41 | { | |
42 | const struct kexec_file_ops * const *fops; | |
43 | int ret = -ENOEXEC; | |
44 | ||
45 | for (fops = &kexec_file_loaders[0]; *fops && (*fops)->probe; ++fops) { | |
46 | ret = (*fops)->probe(buf, buf_len); | |
47 | if (!ret) { | |
48 | image->fops = *fops; | |
49 | return ret; | |
50 | } | |
51 | } | |
52 | ||
53 | return ret; | |
54 | } | |
55 | ||
a43cac0d DY |
56 | /* Architectures can provide this probe function */ |
57 | int __weak arch_kexec_kernel_image_probe(struct kimage *image, void *buf, | |
58 | unsigned long buf_len) | |
59 | { | |
9ec4ecef AT |
60 | return kexec_image_probe_default(image, buf, buf_len); |
61 | } | |
62 | ||
63 | static void *kexec_image_load_default(struct kimage *image) | |
64 | { | |
65 | if (!image->fops || !image->fops->load) | |
66 | return ERR_PTR(-ENOEXEC); | |
67 | ||
68 | return image->fops->load(image, image->kernel_buf, | |
69 | image->kernel_buf_len, image->initrd_buf, | |
70 | image->initrd_buf_len, image->cmdline_buf, | |
71 | image->cmdline_buf_len); | |
a43cac0d DY |
72 | } |
73 | ||
74 | void * __weak arch_kexec_kernel_image_load(struct kimage *image) | |
75 | { | |
9ec4ecef AT |
76 | return kexec_image_load_default(image); |
77 | } | |
78 | ||
92a98a2b | 79 | int kexec_image_post_load_cleanup_default(struct kimage *image) |
9ec4ecef AT |
80 | { |
81 | if (!image->fops || !image->fops->cleanup) | |
82 | return 0; | |
83 | ||
84 | return image->fops->cleanup(image->image_loader_data); | |
a43cac0d DY |
85 | } |
86 | ||
87 | int __weak arch_kimage_file_post_load_cleanup(struct kimage *image) | |
88 | { | |
9ec4ecef | 89 | return kexec_image_post_load_cleanup_default(image); |
a43cac0d DY |
90 | } |
91 | ||
99d5cadf | 92 | #ifdef CONFIG_KEXEC_SIG |
9ec4ecef AT |
93 | static int kexec_image_verify_sig_default(struct kimage *image, void *buf, |
94 | unsigned long buf_len) | |
95 | { | |
96 | if (!image->fops || !image->fops->verify_sig) { | |
97 | pr_debug("kernel loader does not support signature verification.\n"); | |
98 | return -EKEYREJECTED; | |
99 | } | |
100 | ||
101 | return image->fops->verify_sig(buf, buf_len); | |
102 | } | |
103 | ||
a43cac0d DY |
104 | int __weak arch_kexec_kernel_verify_sig(struct kimage *image, void *buf, |
105 | unsigned long buf_len) | |
106 | { | |
9ec4ecef | 107 | return kexec_image_verify_sig_default(image, buf, buf_len); |
a43cac0d | 108 | } |
978e30c9 | 109 | #endif |
a43cac0d | 110 | |
a43cac0d DY |
111 | /* |
112 | * Free up memory used by kernel, initrd, and command line. This is temporary | |
113 | * memory allocation which is not needed any more after these buffers have | |
114 | * been loaded into separate segments and have been copied elsewhere. | |
115 | */ | |
116 | void kimage_file_post_load_cleanup(struct kimage *image) | |
117 | { | |
118 | struct purgatory_info *pi = &image->purgatory_info; | |
119 | ||
120 | vfree(image->kernel_buf); | |
121 | image->kernel_buf = NULL; | |
122 | ||
123 | vfree(image->initrd_buf); | |
124 | image->initrd_buf = NULL; | |
125 | ||
126 | kfree(image->cmdline_buf); | |
127 | image->cmdline_buf = NULL; | |
128 | ||
129 | vfree(pi->purgatory_buf); | |
130 | pi->purgatory_buf = NULL; | |
131 | ||
132 | vfree(pi->sechdrs); | |
133 | pi->sechdrs = NULL; | |
134 | ||
f31e3386 LR |
135 | #ifdef CONFIG_IMA_KEXEC |
136 | vfree(image->ima_buffer); | |
137 | image->ima_buffer = NULL; | |
138 | #endif /* CONFIG_IMA_KEXEC */ | |
139 | ||
a43cac0d DY |
140 | /* See if architecture has anything to cleanup post load */ |
141 | arch_kimage_file_post_load_cleanup(image); | |
142 | ||
143 | /* | |
144 | * Above call should have called into bootloader to free up | |
145 | * any data stored in kimage->image_loader_data. It should | |
146 | * be ok now to free it up. | |
147 | */ | |
148 | kfree(image->image_loader_data); | |
149 | image->image_loader_data = NULL; | |
150 | } | |
151 | ||
99d5cadf JB |
152 | #ifdef CONFIG_KEXEC_SIG |
153 | static int | |
154 | kimage_validate_signature(struct kimage *image) | |
155 | { | |
99d5cadf JB |
156 | int ret; |
157 | ||
158 | ret = arch_kexec_kernel_verify_sig(image, image->kernel_buf, | |
159 | image->kernel_buf_len); | |
fd7af71b | 160 | if (ret) { |
99d5cadf | 161 | |
99d5cadf | 162 | if (IS_ENABLED(CONFIG_KEXEC_SIG_FORCE)) { |
fd7af71b | 163 | pr_notice("Enforced kernel signature verification failed (%d).\n", ret); |
99d5cadf JB |
164 | return ret; |
165 | } | |
166 | ||
fd7af71b LJ |
167 | /* |
168 | * If IMA is guaranteed to appraise a signature on the kexec | |
29d3c1c8 MG |
169 | * image, permit it even if the kernel is otherwise locked |
170 | * down. | |
171 | */ | |
172 | if (!ima_appraise_signature(READING_KEXEC_IMAGE) && | |
173 | security_locked_down(LOCKDOWN_KEXEC)) | |
174 | return -EPERM; | |
175 | ||
fd7af71b | 176 | pr_debug("kernel signature verification failed (%d).\n", ret); |
99d5cadf JB |
177 | } |
178 | ||
fd7af71b | 179 | return 0; |
99d5cadf JB |
180 | } |
181 | #endif | |
182 | ||
a43cac0d DY |
183 | /* |
184 | * In file mode list of segments is prepared by kernel. Copy relevant | |
185 | * data from user space, do error checking, prepare segment list | |
186 | */ | |
187 | static int | |
188 | kimage_file_prepare_segments(struct kimage *image, int kernel_fd, int initrd_fd, | |
189 | const char __user *cmdline_ptr, | |
190 | unsigned long cmdline_len, unsigned flags) | |
191 | { | |
99d5cadf | 192 | int ret; |
a43cac0d DY |
193 | void *ldata; |
194 | ||
0fa8e084 | 195 | ret = kernel_read_file_from_fd(kernel_fd, 0, &image->kernel_buf, |
88535288 | 196 | INT_MAX, NULL, READING_KEXEC_IMAGE); |
f7a4f689 | 197 | if (ret < 0) |
a43cac0d | 198 | return ret; |
f7a4f689 | 199 | image->kernel_buf_len = ret; |
a43cac0d DY |
200 | |
201 | /* Call arch image probe handlers */ | |
202 | ret = arch_kexec_kernel_image_probe(image, image->kernel_buf, | |
203 | image->kernel_buf_len); | |
a43cac0d DY |
204 | if (ret) |
205 | goto out; | |
206 | ||
99d5cadf JB |
207 | #ifdef CONFIG_KEXEC_SIG |
208 | ret = kimage_validate_signature(image); | |
209 | ||
210 | if (ret) | |
a43cac0d | 211 | goto out; |
a43cac0d DY |
212 | #endif |
213 | /* It is possible that there no initramfs is being loaded */ | |
214 | if (!(flags & KEXEC_FILE_NO_INITRAMFS)) { | |
0fa8e084 | 215 | ret = kernel_read_file_from_fd(initrd_fd, 0, &image->initrd_buf, |
88535288 | 216 | INT_MAX, NULL, |
b804defe | 217 | READING_KEXEC_INITRAMFS); |
f7a4f689 | 218 | if (ret < 0) |
a43cac0d | 219 | goto out; |
f7a4f689 KC |
220 | image->initrd_buf_len = ret; |
221 | ret = 0; | |
a43cac0d DY |
222 | } |
223 | ||
224 | if (cmdline_len) { | |
a9bd8dfa AV |
225 | image->cmdline_buf = memdup_user(cmdline_ptr, cmdline_len); |
226 | if (IS_ERR(image->cmdline_buf)) { | |
227 | ret = PTR_ERR(image->cmdline_buf); | |
228 | image->cmdline_buf = NULL; | |
a43cac0d DY |
229 | goto out; |
230 | } | |
231 | ||
232 | image->cmdline_buf_len = cmdline_len; | |
233 | ||
234 | /* command line should be a string with last byte null */ | |
235 | if (image->cmdline_buf[cmdline_len - 1] != '\0') { | |
236 | ret = -EINVAL; | |
237 | goto out; | |
238 | } | |
6a31fcd4 | 239 | |
4834177e | 240 | ima_kexec_cmdline(kernel_fd, image->cmdline_buf, |
6a31fcd4 | 241 | image->cmdline_buf_len - 1); |
a43cac0d DY |
242 | } |
243 | ||
6a31fcd4 PS |
244 | /* IMA needs to pass the measurement list to the next kernel. */ |
245 | ima_add_kexec_buffer(image); | |
246 | ||
a43cac0d DY |
247 | /* Call arch image load handlers */ |
248 | ldata = arch_kexec_kernel_image_load(image); | |
249 | ||
250 | if (IS_ERR(ldata)) { | |
251 | ret = PTR_ERR(ldata); | |
252 | goto out; | |
253 | } | |
254 | ||
255 | image->image_loader_data = ldata; | |
256 | out: | |
257 | /* In case of error, free up all allocated memory in this function */ | |
258 | if (ret) | |
259 | kimage_file_post_load_cleanup(image); | |
260 | return ret; | |
261 | } | |
262 | ||
263 | static int | |
264 | kimage_file_alloc_init(struct kimage **rimage, int kernel_fd, | |
265 | int initrd_fd, const char __user *cmdline_ptr, | |
266 | unsigned long cmdline_len, unsigned long flags) | |
267 | { | |
268 | int ret; | |
269 | struct kimage *image; | |
270 | bool kexec_on_panic = flags & KEXEC_FILE_ON_CRASH; | |
271 | ||
272 | image = do_kimage_alloc_init(); | |
273 | if (!image) | |
274 | return -ENOMEM; | |
275 | ||
276 | image->file_mode = 1; | |
277 | ||
278 | if (kexec_on_panic) { | |
279 | /* Enable special crash kernel control page alloc policy. */ | |
280 | image->control_page = crashk_res.start; | |
281 | image->type = KEXEC_TYPE_CRASH; | |
282 | } | |
283 | ||
284 | ret = kimage_file_prepare_segments(image, kernel_fd, initrd_fd, | |
285 | cmdline_ptr, cmdline_len, flags); | |
286 | if (ret) | |
287 | goto out_free_image; | |
288 | ||
289 | ret = sanity_check_segment_list(image); | |
290 | if (ret) | |
291 | goto out_free_post_load_bufs; | |
292 | ||
293 | ret = -ENOMEM; | |
294 | image->control_code_page = kimage_alloc_control_pages(image, | |
295 | get_order(KEXEC_CONTROL_PAGE_SIZE)); | |
296 | if (!image->control_code_page) { | |
297 | pr_err("Could not allocate control_code_buffer\n"); | |
298 | goto out_free_post_load_bufs; | |
299 | } | |
300 | ||
301 | if (!kexec_on_panic) { | |
302 | image->swap_page = kimage_alloc_control_pages(image, 0); | |
303 | if (!image->swap_page) { | |
304 | pr_err("Could not allocate swap buffer\n"); | |
305 | goto out_free_control_pages; | |
306 | } | |
307 | } | |
308 | ||
309 | *rimage = image; | |
310 | return 0; | |
311 | out_free_control_pages: | |
312 | kimage_free_page_list(&image->control_pages); | |
313 | out_free_post_load_bufs: | |
314 | kimage_file_post_load_cleanup(image); | |
315 | out_free_image: | |
316 | kfree(image); | |
317 | return ret; | |
318 | } | |
319 | ||
320 | SYSCALL_DEFINE5(kexec_file_load, int, kernel_fd, int, initrd_fd, | |
321 | unsigned long, cmdline_len, const char __user *, cmdline_ptr, | |
322 | unsigned long, flags) | |
323 | { | |
324 | int ret = 0, i; | |
325 | struct kimage **dest_image, *image; | |
326 | ||
327 | /* We only trust the superuser with rebooting the system. */ | |
328 | if (!capable(CAP_SYS_BOOT) || kexec_load_disabled) | |
329 | return -EPERM; | |
330 | ||
331 | /* Make sure we have a legal set of flags */ | |
332 | if (flags != (flags & KEXEC_FILE_FLAGS)) | |
333 | return -EINVAL; | |
334 | ||
335 | image = NULL; | |
336 | ||
337 | if (!mutex_trylock(&kexec_mutex)) | |
338 | return -EBUSY; | |
339 | ||
340 | dest_image = &kexec_image; | |
9b492cf5 | 341 | if (flags & KEXEC_FILE_ON_CRASH) { |
a43cac0d | 342 | dest_image = &kexec_crash_image; |
9b492cf5 XP |
343 | if (kexec_crash_image) |
344 | arch_kexec_unprotect_crashkres(); | |
345 | } | |
a43cac0d DY |
346 | |
347 | if (flags & KEXEC_FILE_UNLOAD) | |
348 | goto exchange; | |
349 | ||
350 | /* | |
351 | * In case of crash, new kernel gets loaded in reserved region. It is | |
352 | * same memory where old crash kernel might be loaded. Free any | |
353 | * current crash dump kernel before we corrupt it. | |
354 | */ | |
355 | if (flags & KEXEC_FILE_ON_CRASH) | |
356 | kimage_free(xchg(&kexec_crash_image, NULL)); | |
357 | ||
358 | ret = kimage_file_alloc_init(&image, kernel_fd, initrd_fd, cmdline_ptr, | |
359 | cmdline_len, flags); | |
360 | if (ret) | |
361 | goto out; | |
362 | ||
363 | ret = machine_kexec_prepare(image); | |
364 | if (ret) | |
365 | goto out; | |
366 | ||
1229384f XP |
367 | /* |
368 | * Some architecture(like S390) may touch the crash memory before | |
369 | * machine_kexec_prepare(), we must copy vmcoreinfo data after it. | |
370 | */ | |
371 | ret = kimage_crash_copy_vmcoreinfo(image); | |
372 | if (ret) | |
373 | goto out; | |
374 | ||
a43cac0d DY |
375 | ret = kexec_calculate_store_digests(image); |
376 | if (ret) | |
377 | goto out; | |
378 | ||
379 | for (i = 0; i < image->nr_segments; i++) { | |
380 | struct kexec_segment *ksegment; | |
381 | ||
382 | ksegment = &image->segment[i]; | |
383 | pr_debug("Loading segment %d: buf=0x%p bufsz=0x%zx mem=0x%lx memsz=0x%zx\n", | |
384 | i, ksegment->buf, ksegment->bufsz, ksegment->mem, | |
385 | ksegment->memsz); | |
386 | ||
387 | ret = kimage_load_segment(image, &image->segment[i]); | |
388 | if (ret) | |
389 | goto out; | |
390 | } | |
391 | ||
392 | kimage_terminate(image); | |
393 | ||
de68e4da PT |
394 | ret = machine_kexec_post_load(image); |
395 | if (ret) | |
396 | goto out; | |
397 | ||
a43cac0d DY |
398 | /* |
399 | * Free up any temporary buffers allocated which are not needed | |
400 | * after image has been loaded | |
401 | */ | |
402 | kimage_file_post_load_cleanup(image); | |
403 | exchange: | |
404 | image = xchg(dest_image, image); | |
405 | out: | |
9b492cf5 XP |
406 | if ((flags & KEXEC_FILE_ON_CRASH) && kexec_crash_image) |
407 | arch_kexec_protect_crashkres(); | |
408 | ||
a43cac0d DY |
409 | mutex_unlock(&kexec_mutex); |
410 | kimage_free(image); | |
411 | return ret; | |
412 | } | |
413 | ||
414 | static int locate_mem_hole_top_down(unsigned long start, unsigned long end, | |
415 | struct kexec_buf *kbuf) | |
416 | { | |
417 | struct kimage *image = kbuf->image; | |
418 | unsigned long temp_start, temp_end; | |
419 | ||
420 | temp_end = min(end, kbuf->buf_max); | |
421 | temp_start = temp_end - kbuf->memsz; | |
422 | ||
423 | do { | |
424 | /* align down start */ | |
425 | temp_start = temp_start & (~(kbuf->buf_align - 1)); | |
426 | ||
427 | if (temp_start < start || temp_start < kbuf->buf_min) | |
428 | return 0; | |
429 | ||
430 | temp_end = temp_start + kbuf->memsz - 1; | |
431 | ||
432 | /* | |
433 | * Make sure this does not conflict with any of existing | |
434 | * segments | |
435 | */ | |
436 | if (kimage_is_destination_range(image, temp_start, temp_end)) { | |
437 | temp_start = temp_start - PAGE_SIZE; | |
438 | continue; | |
439 | } | |
440 | ||
441 | /* We found a suitable memory range */ | |
442 | break; | |
443 | } while (1); | |
444 | ||
445 | /* If we are here, we found a suitable memory range */ | |
446 | kbuf->mem = temp_start; | |
447 | ||
448 | /* Success, stop navigating through remaining System RAM ranges */ | |
449 | return 1; | |
450 | } | |
451 | ||
452 | static int locate_mem_hole_bottom_up(unsigned long start, unsigned long end, | |
453 | struct kexec_buf *kbuf) | |
454 | { | |
455 | struct kimage *image = kbuf->image; | |
456 | unsigned long temp_start, temp_end; | |
457 | ||
458 | temp_start = max(start, kbuf->buf_min); | |
459 | ||
460 | do { | |
461 | temp_start = ALIGN(temp_start, kbuf->buf_align); | |
462 | temp_end = temp_start + kbuf->memsz - 1; | |
463 | ||
464 | if (temp_end > end || temp_end > kbuf->buf_max) | |
465 | return 0; | |
466 | /* | |
467 | * Make sure this does not conflict with any of existing | |
468 | * segments | |
469 | */ | |
470 | if (kimage_is_destination_range(image, temp_start, temp_end)) { | |
471 | temp_start = temp_start + PAGE_SIZE; | |
472 | continue; | |
473 | } | |
474 | ||
475 | /* We found a suitable memory range */ | |
476 | break; | |
477 | } while (1); | |
478 | ||
479 | /* If we are here, we found a suitable memory range */ | |
480 | kbuf->mem = temp_start; | |
481 | ||
482 | /* Success, stop navigating through remaining System RAM ranges */ | |
483 | return 1; | |
484 | } | |
485 | ||
1d2e733b | 486 | static int locate_mem_hole_callback(struct resource *res, void *arg) |
a43cac0d DY |
487 | { |
488 | struct kexec_buf *kbuf = (struct kexec_buf *)arg; | |
1d2e733b | 489 | u64 start = res->start, end = res->end; |
a43cac0d DY |
490 | unsigned long sz = end - start + 1; |
491 | ||
492 | /* Returning 0 will take to next memory range */ | |
3fe4f499 DH |
493 | |
494 | /* Don't use memory that will be detected and handled by a driver. */ | |
7cf603d1 | 495 | if (res->flags & IORESOURCE_SYSRAM_DRIVER_MANAGED) |
3fe4f499 DH |
496 | return 0; |
497 | ||
a43cac0d DY |
498 | if (sz < kbuf->memsz) |
499 | return 0; | |
500 | ||
501 | if (end < kbuf->buf_min || start > kbuf->buf_max) | |
502 | return 0; | |
503 | ||
504 | /* | |
505 | * Allocate memory top down with-in ram range. Otherwise bottom up | |
506 | * allocation. | |
507 | */ | |
508 | if (kbuf->top_down) | |
509 | return locate_mem_hole_top_down(start, end, kbuf); | |
510 | return locate_mem_hole_bottom_up(start, end, kbuf); | |
511 | } | |
512 | ||
350e88ba | 513 | #ifdef CONFIG_ARCH_KEEP_MEMBLOCK |
735c2f90 AT |
514 | static int kexec_walk_memblock(struct kexec_buf *kbuf, |
515 | int (*func)(struct resource *, void *)) | |
516 | { | |
517 | int ret = 0; | |
518 | u64 i; | |
519 | phys_addr_t mstart, mend; | |
520 | struct resource res = { }; | |
521 | ||
497e1858 AT |
522 | if (kbuf->image->type == KEXEC_TYPE_CRASH) |
523 | return func(&crashk_res, kbuf); | |
524 | ||
f7892d8e DH |
525 | /* |
526 | * Using MEMBLOCK_NONE will properly skip MEMBLOCK_DRIVER_MANAGED. See | |
527 | * IORESOURCE_SYSRAM_DRIVER_MANAGED handling in | |
528 | * locate_mem_hole_callback(). | |
529 | */ | |
735c2f90 | 530 | if (kbuf->top_down) { |
497e1858 | 531 | for_each_free_mem_range_reverse(i, NUMA_NO_NODE, MEMBLOCK_NONE, |
735c2f90 AT |
532 | &mstart, &mend, NULL) { |
533 | /* | |
534 | * In memblock, end points to the first byte after the | |
535 | * range while in kexec, end points to the last byte | |
536 | * in the range. | |
537 | */ | |
538 | res.start = mstart; | |
539 | res.end = mend - 1; | |
540 | ret = func(&res, kbuf); | |
541 | if (ret) | |
542 | break; | |
543 | } | |
544 | } else { | |
497e1858 AT |
545 | for_each_free_mem_range(i, NUMA_NO_NODE, MEMBLOCK_NONE, |
546 | &mstart, &mend, NULL) { | |
735c2f90 AT |
547 | /* |
548 | * In memblock, end points to the first byte after the | |
549 | * range while in kexec, end points to the last byte | |
550 | * in the range. | |
551 | */ | |
552 | res.start = mstart; | |
553 | res.end = mend - 1; | |
554 | ret = func(&res, kbuf); | |
555 | if (ret) | |
556 | break; | |
557 | } | |
558 | } | |
559 | ||
560 | return ret; | |
561 | } | |
350e88ba MR |
562 | #else |
563 | static int kexec_walk_memblock(struct kexec_buf *kbuf, | |
564 | int (*func)(struct resource *, void *)) | |
565 | { | |
566 | return 0; | |
567 | } | |
735c2f90 AT |
568 | #endif |
569 | ||
60fe3910 | 570 | /** |
735c2f90 | 571 | * kexec_walk_resources - call func(data) on free memory regions |
60fe3910 TJB |
572 | * @kbuf: Context info for the search. Also passed to @func. |
573 | * @func: Function to call for each memory region. | |
574 | * | |
575 | * Return: The memory walk will stop when func returns a non-zero value | |
576 | * and that value will be returned. If all free regions are visited without | |
577 | * func returning non-zero, then zero will be returned. | |
578 | */ | |
735c2f90 AT |
579 | static int kexec_walk_resources(struct kexec_buf *kbuf, |
580 | int (*func)(struct resource *, void *)) | |
60fe3910 TJB |
581 | { |
582 | if (kbuf->image->type == KEXEC_TYPE_CRASH) | |
583 | return walk_iomem_res_desc(crashk_res.desc, | |
584 | IORESOURCE_SYSTEM_RAM | IORESOURCE_BUSY, | |
585 | crashk_res.start, crashk_res.end, | |
586 | kbuf, func); | |
587 | else | |
588 | return walk_system_ram_res(0, ULONG_MAX, kbuf, func); | |
589 | } | |
590 | ||
e2e806f9 TJB |
591 | /** |
592 | * kexec_locate_mem_hole - find free memory for the purgatory or the next kernel | |
593 | * @kbuf: Parameters for the memory search. | |
594 | * | |
595 | * On success, kbuf->mem will have the start address of the memory region found. | |
596 | * | |
597 | * Return: 0 on success, negative errno on error. | |
598 | */ | |
599 | int kexec_locate_mem_hole(struct kexec_buf *kbuf) | |
600 | { | |
601 | int ret; | |
602 | ||
b6664ba4 AT |
603 | /* Arch knows where to place */ |
604 | if (kbuf->mem != KEXEC_BUF_MEM_UNKNOWN) | |
605 | return 0; | |
606 | ||
350e88ba | 607 | if (!IS_ENABLED(CONFIG_ARCH_KEEP_MEMBLOCK)) |
735c2f90 AT |
608 | ret = kexec_walk_resources(kbuf, locate_mem_hole_callback); |
609 | else | |
610 | ret = kexec_walk_memblock(kbuf, locate_mem_hole_callback); | |
e2e806f9 TJB |
611 | |
612 | return ret == 1 ? 0 : -EADDRNOTAVAIL; | |
613 | } | |
614 | ||
f891f197 HB |
615 | /** |
616 | * arch_kexec_locate_mem_hole - Find free memory to place the segments. | |
617 | * @kbuf: Parameters for the memory search. | |
618 | * | |
619 | * On success, kbuf->mem will have the start address of the memory region found. | |
620 | * | |
621 | * Return: 0 on success, negative errno on error. | |
622 | */ | |
623 | int __weak arch_kexec_locate_mem_hole(struct kexec_buf *kbuf) | |
624 | { | |
625 | return kexec_locate_mem_hole(kbuf); | |
626 | } | |
627 | ||
ec2b9bfa TJB |
628 | /** |
629 | * kexec_add_buffer - place a buffer in a kexec segment | |
630 | * @kbuf: Buffer contents and memory parameters. | |
631 | * | |
632 | * This function assumes that kexec_mutex is held. | |
633 | * On successful return, @kbuf->mem will have the physical address of | |
634 | * the buffer in memory. | |
635 | * | |
636 | * Return: 0 on success, negative errno on error. | |
a43cac0d | 637 | */ |
ec2b9bfa | 638 | int kexec_add_buffer(struct kexec_buf *kbuf) |
a43cac0d | 639 | { |
a43cac0d | 640 | struct kexec_segment *ksegment; |
a43cac0d DY |
641 | int ret; |
642 | ||
643 | /* Currently adding segment this way is allowed only in file mode */ | |
ec2b9bfa | 644 | if (!kbuf->image->file_mode) |
a43cac0d DY |
645 | return -EINVAL; |
646 | ||
ec2b9bfa | 647 | if (kbuf->image->nr_segments >= KEXEC_SEGMENT_MAX) |
a43cac0d DY |
648 | return -EINVAL; |
649 | ||
650 | /* | |
651 | * Make sure we are not trying to add buffer after allocating | |
652 | * control pages. All segments need to be placed first before | |
653 | * any control pages are allocated. As control page allocation | |
654 | * logic goes through list of segments to make sure there are | |
655 | * no destination overlaps. | |
656 | */ | |
ec2b9bfa | 657 | if (!list_empty(&kbuf->image->control_pages)) { |
a43cac0d DY |
658 | WARN_ON(1); |
659 | return -EINVAL; | |
660 | } | |
661 | ||
ec2b9bfa TJB |
662 | /* Ensure minimum alignment needed for segments. */ |
663 | kbuf->memsz = ALIGN(kbuf->memsz, PAGE_SIZE); | |
664 | kbuf->buf_align = max(kbuf->buf_align, PAGE_SIZE); | |
a43cac0d DY |
665 | |
666 | /* Walk the RAM ranges and allocate a suitable range for the buffer */ | |
f891f197 | 667 | ret = arch_kexec_locate_mem_hole(kbuf); |
e2e806f9 TJB |
668 | if (ret) |
669 | return ret; | |
a43cac0d DY |
670 | |
671 | /* Found a suitable memory range */ | |
ec2b9bfa | 672 | ksegment = &kbuf->image->segment[kbuf->image->nr_segments]; |
a43cac0d DY |
673 | ksegment->kbuf = kbuf->buffer; |
674 | ksegment->bufsz = kbuf->bufsz; | |
675 | ksegment->mem = kbuf->mem; | |
676 | ksegment->memsz = kbuf->memsz; | |
ec2b9bfa | 677 | kbuf->image->nr_segments++; |
a43cac0d DY |
678 | return 0; |
679 | } | |
680 | ||
681 | /* Calculate and store the digest of segments */ | |
682 | static int kexec_calculate_store_digests(struct kimage *image) | |
683 | { | |
684 | struct crypto_shash *tfm; | |
685 | struct shash_desc *desc; | |
686 | int ret = 0, i, j, zero_buf_sz, sha_region_sz; | |
687 | size_t desc_size, nullsz; | |
688 | char *digest; | |
689 | void *zero_buf; | |
690 | struct kexec_sha_region *sha_regions; | |
691 | struct purgatory_info *pi = &image->purgatory_info; | |
692 | ||
b799a09f AT |
693 | if (!IS_ENABLED(CONFIG_ARCH_HAS_KEXEC_PURGATORY)) |
694 | return 0; | |
695 | ||
a43cac0d DY |
696 | zero_buf = __va(page_to_pfn(ZERO_PAGE(0)) << PAGE_SHIFT); |
697 | zero_buf_sz = PAGE_SIZE; | |
698 | ||
699 | tfm = crypto_alloc_shash("sha256", 0, 0); | |
700 | if (IS_ERR(tfm)) { | |
701 | ret = PTR_ERR(tfm); | |
702 | goto out; | |
703 | } | |
704 | ||
705 | desc_size = crypto_shash_descsize(tfm) + sizeof(*desc); | |
706 | desc = kzalloc(desc_size, GFP_KERNEL); | |
707 | if (!desc) { | |
708 | ret = -ENOMEM; | |
709 | goto out_free_tfm; | |
710 | } | |
711 | ||
712 | sha_region_sz = KEXEC_SEGMENT_MAX * sizeof(struct kexec_sha_region); | |
713 | sha_regions = vzalloc(sha_region_sz); | |
31d82c2c JJB |
714 | if (!sha_regions) { |
715 | ret = -ENOMEM; | |
a43cac0d | 716 | goto out_free_desc; |
31d82c2c | 717 | } |
a43cac0d DY |
718 | |
719 | desc->tfm = tfm; | |
a43cac0d DY |
720 | |
721 | ret = crypto_shash_init(desc); | |
722 | if (ret < 0) | |
723 | goto out_free_sha_regions; | |
724 | ||
725 | digest = kzalloc(SHA256_DIGEST_SIZE, GFP_KERNEL); | |
726 | if (!digest) { | |
727 | ret = -ENOMEM; | |
728 | goto out_free_sha_regions; | |
729 | } | |
730 | ||
731 | for (j = i = 0; i < image->nr_segments; i++) { | |
732 | struct kexec_segment *ksegment; | |
733 | ||
734 | ksegment = &image->segment[i]; | |
735 | /* | |
736 | * Skip purgatory as it will be modified once we put digest | |
737 | * info in purgatory. | |
738 | */ | |
739 | if (ksegment->kbuf == pi->purgatory_buf) | |
740 | continue; | |
741 | ||
742 | ret = crypto_shash_update(desc, ksegment->kbuf, | |
743 | ksegment->bufsz); | |
744 | if (ret) | |
745 | break; | |
746 | ||
747 | /* | |
748 | * Assume rest of the buffer is filled with zero and | |
749 | * update digest accordingly. | |
750 | */ | |
751 | nullsz = ksegment->memsz - ksegment->bufsz; | |
752 | while (nullsz) { | |
753 | unsigned long bytes = nullsz; | |
754 | ||
755 | if (bytes > zero_buf_sz) | |
756 | bytes = zero_buf_sz; | |
757 | ret = crypto_shash_update(desc, zero_buf, bytes); | |
758 | if (ret) | |
759 | break; | |
760 | nullsz -= bytes; | |
761 | } | |
762 | ||
763 | if (ret) | |
764 | break; | |
765 | ||
766 | sha_regions[j].start = ksegment->mem; | |
767 | sha_regions[j].len = ksegment->memsz; | |
768 | j++; | |
769 | } | |
770 | ||
771 | if (!ret) { | |
772 | ret = crypto_shash_final(desc, digest); | |
773 | if (ret) | |
774 | goto out_free_digest; | |
40c50c1f TG |
775 | ret = kexec_purgatory_get_set_symbol(image, "purgatory_sha_regions", |
776 | sha_regions, sha_region_sz, 0); | |
a43cac0d DY |
777 | if (ret) |
778 | goto out_free_digest; | |
779 | ||
40c50c1f TG |
780 | ret = kexec_purgatory_get_set_symbol(image, "purgatory_sha256_digest", |
781 | digest, SHA256_DIGEST_SIZE, 0); | |
a43cac0d DY |
782 | if (ret) |
783 | goto out_free_digest; | |
784 | } | |
785 | ||
786 | out_free_digest: | |
787 | kfree(digest); | |
788 | out_free_sha_regions: | |
789 | vfree(sha_regions); | |
790 | out_free_desc: | |
791 | kfree(desc); | |
792 | out_free_tfm: | |
793 | kfree(tfm); | |
794 | out: | |
795 | return ret; | |
796 | } | |
797 | ||
b799a09f | 798 | #ifdef CONFIG_ARCH_HAS_KEXEC_PURGATORY |
93045705 PR |
799 | /* |
800 | * kexec_purgatory_setup_kbuf - prepare buffer to load purgatory. | |
801 | * @pi: Purgatory to be loaded. | |
802 | * @kbuf: Buffer to setup. | |
803 | * | |
804 | * Allocates the memory needed for the buffer. Caller is responsible to free | |
805 | * the memory after use. | |
806 | * | |
807 | * Return: 0 on success, negative errno on error. | |
808 | */ | |
809 | static int kexec_purgatory_setup_kbuf(struct purgatory_info *pi, | |
810 | struct kexec_buf *kbuf) | |
a43cac0d | 811 | { |
93045705 PR |
812 | const Elf_Shdr *sechdrs; |
813 | unsigned long bss_align; | |
814 | unsigned long bss_sz; | |
815 | unsigned long align; | |
816 | int i, ret; | |
a43cac0d | 817 | |
93045705 | 818 | sechdrs = (void *)pi->ehdr + pi->ehdr->e_shoff; |
3be3f61d PR |
819 | kbuf->buf_align = bss_align = 1; |
820 | kbuf->bufsz = bss_sz = 0; | |
93045705 PR |
821 | |
822 | for (i = 0; i < pi->ehdr->e_shnum; i++) { | |
823 | if (!(sechdrs[i].sh_flags & SHF_ALLOC)) | |
824 | continue; | |
825 | ||
826 | align = sechdrs[i].sh_addralign; | |
827 | if (sechdrs[i].sh_type != SHT_NOBITS) { | |
828 | if (kbuf->buf_align < align) | |
829 | kbuf->buf_align = align; | |
830 | kbuf->bufsz = ALIGN(kbuf->bufsz, align); | |
831 | kbuf->bufsz += sechdrs[i].sh_size; | |
832 | } else { | |
833 | if (bss_align < align) | |
834 | bss_align = align; | |
835 | bss_sz = ALIGN(bss_sz, align); | |
836 | bss_sz += sechdrs[i].sh_size; | |
837 | } | |
838 | } | |
839 | kbuf->bufsz = ALIGN(kbuf->bufsz, bss_align); | |
840 | kbuf->memsz = kbuf->bufsz + bss_sz; | |
841 | if (kbuf->buf_align < bss_align) | |
842 | kbuf->buf_align = bss_align; | |
843 | ||
844 | kbuf->buffer = vzalloc(kbuf->bufsz); | |
845 | if (!kbuf->buffer) | |
846 | return -ENOMEM; | |
847 | pi->purgatory_buf = kbuf->buffer; | |
848 | ||
849 | ret = kexec_add_buffer(kbuf); | |
850 | if (ret) | |
851 | goto out; | |
93045705 PR |
852 | |
853 | return 0; | |
854 | out: | |
855 | vfree(pi->purgatory_buf); | |
856 | pi->purgatory_buf = NULL; | |
857 | return ret; | |
858 | } | |
859 | ||
860 | /* | |
861 | * kexec_purgatory_setup_sechdrs - prepares the pi->sechdrs buffer. | |
862 | * @pi: Purgatory to be loaded. | |
863 | * @kbuf: Buffer prepared to store purgatory. | |
864 | * | |
865 | * Allocates the memory needed for the buffer. Caller is responsible to free | |
866 | * the memory after use. | |
867 | * | |
868 | * Return: 0 on success, negative errno on error. | |
869 | */ | |
870 | static int kexec_purgatory_setup_sechdrs(struct purgatory_info *pi, | |
871 | struct kexec_buf *kbuf) | |
872 | { | |
93045705 PR |
873 | unsigned long bss_addr; |
874 | unsigned long offset; | |
93045705 | 875 | Elf_Shdr *sechdrs; |
93045705 | 876 | int i; |
a43cac0d | 877 | |
8da0b724 PR |
878 | /* |
879 | * The section headers in kexec_purgatory are read-only. In order to | |
880 | * have them modifiable make a temporary copy. | |
881 | */ | |
fad953ce | 882 | sechdrs = vzalloc(array_size(sizeof(Elf_Shdr), pi->ehdr->e_shnum)); |
a43cac0d DY |
883 | if (!sechdrs) |
884 | return -ENOMEM; | |
93045705 PR |
885 | memcpy(sechdrs, (void *)pi->ehdr + pi->ehdr->e_shoff, |
886 | pi->ehdr->e_shnum * sizeof(Elf_Shdr)); | |
887 | pi->sechdrs = sechdrs; | |
a43cac0d | 888 | |
620f697c PR |
889 | offset = 0; |
890 | bss_addr = kbuf->mem + kbuf->bufsz; | |
f1b1cca3 | 891 | kbuf->image->start = pi->ehdr->e_entry; |
a43cac0d DY |
892 | |
893 | for (i = 0; i < pi->ehdr->e_shnum; i++) { | |
93045705 | 894 | unsigned long align; |
620f697c | 895 | void *src, *dst; |
93045705 | 896 | |
a43cac0d DY |
897 | if (!(sechdrs[i].sh_flags & SHF_ALLOC)) |
898 | continue; | |
899 | ||
900 | align = sechdrs[i].sh_addralign; | |
f1b1cca3 | 901 | if (sechdrs[i].sh_type == SHT_NOBITS) { |
a43cac0d DY |
902 | bss_addr = ALIGN(bss_addr, align); |
903 | sechdrs[i].sh_addr = bss_addr; | |
904 | bss_addr += sechdrs[i].sh_size; | |
f1b1cca3 PR |
905 | continue; |
906 | } | |
907 | ||
620f697c | 908 | offset = ALIGN(offset, align); |
f1b1cca3 PR |
909 | if (sechdrs[i].sh_flags & SHF_EXECINSTR && |
910 | pi->ehdr->e_entry >= sechdrs[i].sh_addr && | |
911 | pi->ehdr->e_entry < (sechdrs[i].sh_addr | |
912 | + sechdrs[i].sh_size)) { | |
913 | kbuf->image->start -= sechdrs[i].sh_addr; | |
620f697c | 914 | kbuf->image->start += kbuf->mem + offset; |
a43cac0d | 915 | } |
a43cac0d | 916 | |
8da0b724 | 917 | src = (void *)pi->ehdr + sechdrs[i].sh_offset; |
620f697c PR |
918 | dst = pi->purgatory_buf + offset; |
919 | memcpy(dst, src, sechdrs[i].sh_size); | |
920 | ||
921 | sechdrs[i].sh_addr = kbuf->mem + offset; | |
8da0b724 | 922 | sechdrs[i].sh_offset = offset; |
620f697c | 923 | offset += sechdrs[i].sh_size; |
f1b1cca3 | 924 | } |
a43cac0d | 925 | |
93045705 | 926 | return 0; |
a43cac0d DY |
927 | } |
928 | ||
929 | static int kexec_apply_relocations(struct kimage *image) | |
930 | { | |
931 | int i, ret; | |
932 | struct purgatory_info *pi = &image->purgatory_info; | |
8aec395b PR |
933 | const Elf_Shdr *sechdrs; |
934 | ||
935 | sechdrs = (void *)pi->ehdr + pi->ehdr->e_shoff; | |
a43cac0d | 936 | |
a43cac0d | 937 | for (i = 0; i < pi->ehdr->e_shnum; i++) { |
8aec395b PR |
938 | const Elf_Shdr *relsec; |
939 | const Elf_Shdr *symtab; | |
940 | Elf_Shdr *section; | |
941 | ||
942 | relsec = sechdrs + i; | |
a43cac0d | 943 | |
8aec395b PR |
944 | if (relsec->sh_type != SHT_RELA && |
945 | relsec->sh_type != SHT_REL) | |
a43cac0d DY |
946 | continue; |
947 | ||
948 | /* | |
949 | * For section of type SHT_RELA/SHT_REL, | |
950 | * ->sh_link contains section header index of associated | |
951 | * symbol table. And ->sh_info contains section header | |
952 | * index of section to which relocations apply. | |
953 | */ | |
8aec395b PR |
954 | if (relsec->sh_info >= pi->ehdr->e_shnum || |
955 | relsec->sh_link >= pi->ehdr->e_shnum) | |
a43cac0d DY |
956 | return -ENOEXEC; |
957 | ||
8aec395b PR |
958 | section = pi->sechdrs + relsec->sh_info; |
959 | symtab = sechdrs + relsec->sh_link; | |
a43cac0d DY |
960 | |
961 | if (!(section->sh_flags & SHF_ALLOC)) | |
962 | continue; | |
963 | ||
964 | /* | |
965 | * symtab->sh_link contain section header index of associated | |
966 | * string table. | |
967 | */ | |
968 | if (symtab->sh_link >= pi->ehdr->e_shnum) | |
969 | /* Invalid section number? */ | |
970 | continue; | |
971 | ||
972 | /* | |
973 | * Respective architecture needs to provide support for applying | |
974 | * relocations of type SHT_RELA/SHT_REL. | |
975 | */ | |
8aec395b PR |
976 | if (relsec->sh_type == SHT_RELA) |
977 | ret = arch_kexec_apply_relocations_add(pi, section, | |
978 | relsec, symtab); | |
979 | else if (relsec->sh_type == SHT_REL) | |
980 | ret = arch_kexec_apply_relocations(pi, section, | |
981 | relsec, symtab); | |
a43cac0d DY |
982 | if (ret) |
983 | return ret; | |
984 | } | |
985 | ||
986 | return 0; | |
987 | } | |
988 | ||
3be3f61d PR |
989 | /* |
990 | * kexec_load_purgatory - Load and relocate the purgatory object. | |
991 | * @image: Image to add the purgatory to. | |
992 | * @kbuf: Memory parameters to use. | |
993 | * | |
994 | * Allocates the memory needed for image->purgatory_info.sechdrs and | |
995 | * image->purgatory_info.purgatory_buf/kbuf->buffer. Caller is responsible | |
996 | * to free the memory after use. | |
997 | * | |
998 | * Return: 0 on success, negative errno on error. | |
999 | */ | |
1000 | int kexec_load_purgatory(struct kimage *image, struct kexec_buf *kbuf) | |
a43cac0d DY |
1001 | { |
1002 | struct purgatory_info *pi = &image->purgatory_info; | |
1003 | int ret; | |
1004 | ||
1005 | if (kexec_purgatory_size <= 0) | |
1006 | return -EINVAL; | |
1007 | ||
65c225d3 | 1008 | pi->ehdr = (const Elf_Ehdr *)kexec_purgatory; |
a43cac0d | 1009 | |
3be3f61d | 1010 | ret = kexec_purgatory_setup_kbuf(pi, kbuf); |
a43cac0d DY |
1011 | if (ret) |
1012 | return ret; | |
1013 | ||
3be3f61d | 1014 | ret = kexec_purgatory_setup_sechdrs(pi, kbuf); |
93045705 PR |
1015 | if (ret) |
1016 | goto out_free_kbuf; | |
1017 | ||
a43cac0d DY |
1018 | ret = kexec_apply_relocations(image); |
1019 | if (ret) | |
1020 | goto out; | |
1021 | ||
a43cac0d DY |
1022 | return 0; |
1023 | out: | |
1024 | vfree(pi->sechdrs); | |
070c43ee | 1025 | pi->sechdrs = NULL; |
93045705 | 1026 | out_free_kbuf: |
a43cac0d | 1027 | vfree(pi->purgatory_buf); |
070c43ee | 1028 | pi->purgatory_buf = NULL; |
a43cac0d DY |
1029 | return ret; |
1030 | } | |
1031 | ||
961d921a PR |
1032 | /* |
1033 | * kexec_purgatory_find_symbol - find a symbol in the purgatory | |
1034 | * @pi: Purgatory to search in. | |
1035 | * @name: Name of the symbol. | |
1036 | * | |
1037 | * Return: pointer to symbol in read-only symtab on success, NULL on error. | |
1038 | */ | |
1039 | static const Elf_Sym *kexec_purgatory_find_symbol(struct purgatory_info *pi, | |
1040 | const char *name) | |
a43cac0d | 1041 | { |
961d921a | 1042 | const Elf_Shdr *sechdrs; |
65c225d3 | 1043 | const Elf_Ehdr *ehdr; |
961d921a | 1044 | const Elf_Sym *syms; |
a43cac0d | 1045 | const char *strtab; |
961d921a | 1046 | int i, k; |
a43cac0d | 1047 | |
961d921a | 1048 | if (!pi->ehdr) |
a43cac0d DY |
1049 | return NULL; |
1050 | ||
a43cac0d | 1051 | ehdr = pi->ehdr; |
961d921a | 1052 | sechdrs = (void *)ehdr + ehdr->e_shoff; |
a43cac0d DY |
1053 | |
1054 | for (i = 0; i < ehdr->e_shnum; i++) { | |
1055 | if (sechdrs[i].sh_type != SHT_SYMTAB) | |
1056 | continue; | |
1057 | ||
1058 | if (sechdrs[i].sh_link >= ehdr->e_shnum) | |
1059 | /* Invalid strtab section number */ | |
1060 | continue; | |
961d921a PR |
1061 | strtab = (void *)ehdr + sechdrs[sechdrs[i].sh_link].sh_offset; |
1062 | syms = (void *)ehdr + sechdrs[i].sh_offset; | |
a43cac0d DY |
1063 | |
1064 | /* Go through symbols for a match */ | |
1065 | for (k = 0; k < sechdrs[i].sh_size/sizeof(Elf_Sym); k++) { | |
1066 | if (ELF_ST_BIND(syms[k].st_info) != STB_GLOBAL) | |
1067 | continue; | |
1068 | ||
1069 | if (strcmp(strtab + syms[k].st_name, name) != 0) | |
1070 | continue; | |
1071 | ||
1072 | if (syms[k].st_shndx == SHN_UNDEF || | |
1073 | syms[k].st_shndx >= ehdr->e_shnum) { | |
1074 | pr_debug("Symbol: %s has bad section index %d.\n", | |
1075 | name, syms[k].st_shndx); | |
1076 | return NULL; | |
1077 | } | |
1078 | ||
1079 | /* Found the symbol we are looking for */ | |
1080 | return &syms[k]; | |
1081 | } | |
1082 | } | |
1083 | ||
1084 | return NULL; | |
1085 | } | |
1086 | ||
1087 | void *kexec_purgatory_get_symbol_addr(struct kimage *image, const char *name) | |
1088 | { | |
1089 | struct purgatory_info *pi = &image->purgatory_info; | |
961d921a | 1090 | const Elf_Sym *sym; |
a43cac0d DY |
1091 | Elf_Shdr *sechdr; |
1092 | ||
1093 | sym = kexec_purgatory_find_symbol(pi, name); | |
1094 | if (!sym) | |
1095 | return ERR_PTR(-EINVAL); | |
1096 | ||
1097 | sechdr = &pi->sechdrs[sym->st_shndx]; | |
1098 | ||
1099 | /* | |
1100 | * Returns the address where symbol will finally be loaded after | |
1101 | * kexec_load_segment() | |
1102 | */ | |
1103 | return (void *)(sechdr->sh_addr + sym->st_value); | |
1104 | } | |
1105 | ||
1106 | /* | |
1107 | * Get or set value of a symbol. If "get_value" is true, symbol value is | |
1108 | * returned in buf otherwise symbol value is set based on value in buf. | |
1109 | */ | |
1110 | int kexec_purgatory_get_set_symbol(struct kimage *image, const char *name, | |
1111 | void *buf, unsigned int size, bool get_value) | |
1112 | { | |
a43cac0d | 1113 | struct purgatory_info *pi = &image->purgatory_info; |
961d921a PR |
1114 | const Elf_Sym *sym; |
1115 | Elf_Shdr *sec; | |
a43cac0d DY |
1116 | char *sym_buf; |
1117 | ||
1118 | sym = kexec_purgatory_find_symbol(pi, name); | |
1119 | if (!sym) | |
1120 | return -EINVAL; | |
1121 | ||
1122 | if (sym->st_size != size) { | |
1123 | pr_err("symbol %s size mismatch: expected %lu actual %u\n", | |
1124 | name, (unsigned long)sym->st_size, size); | |
1125 | return -EINVAL; | |
1126 | } | |
1127 | ||
961d921a | 1128 | sec = pi->sechdrs + sym->st_shndx; |
a43cac0d | 1129 | |
961d921a | 1130 | if (sec->sh_type == SHT_NOBITS) { |
a43cac0d DY |
1131 | pr_err("symbol %s is in a bss section. Cannot %s\n", name, |
1132 | get_value ? "get" : "set"); | |
1133 | return -EINVAL; | |
1134 | } | |
1135 | ||
8da0b724 | 1136 | sym_buf = (char *)pi->purgatory_buf + sec->sh_offset + sym->st_value; |
a43cac0d DY |
1137 | |
1138 | if (get_value) | |
1139 | memcpy((void *)buf, sym_buf, size); | |
1140 | else | |
1141 | memcpy((void *)sym_buf, buf, size); | |
1142 | ||
1143 | return 0; | |
1144 | } | |
b799a09f | 1145 | #endif /* CONFIG_ARCH_HAS_KEXEC_PURGATORY */ |
babac4a8 AT |
1146 | |
1147 | int crash_exclude_mem_range(struct crash_mem *mem, | |
1148 | unsigned long long mstart, unsigned long long mend) | |
1149 | { | |
1150 | int i, j; | |
a2e9a95d | 1151 | unsigned long long start, end, p_start, p_end; |
babac4a8 AT |
1152 | struct crash_mem_range temp_range = {0, 0}; |
1153 | ||
1154 | for (i = 0; i < mem->nr_ranges; i++) { | |
1155 | start = mem->ranges[i].start; | |
1156 | end = mem->ranges[i].end; | |
a2e9a95d LJ |
1157 | p_start = mstart; |
1158 | p_end = mend; | |
babac4a8 AT |
1159 | |
1160 | if (mstart > end || mend < start) | |
1161 | continue; | |
1162 | ||
1163 | /* Truncate any area outside of range */ | |
1164 | if (mstart < start) | |
a2e9a95d | 1165 | p_start = start; |
babac4a8 | 1166 | if (mend > end) |
a2e9a95d | 1167 | p_end = end; |
babac4a8 AT |
1168 | |
1169 | /* Found completely overlapping range */ | |
a2e9a95d | 1170 | if (p_start == start && p_end == end) { |
babac4a8 AT |
1171 | mem->ranges[i].start = 0; |
1172 | mem->ranges[i].end = 0; | |
1173 | if (i < mem->nr_ranges - 1) { | |
1174 | /* Shift rest of the ranges to left */ | |
1175 | for (j = i; j < mem->nr_ranges - 1; j++) { | |
1176 | mem->ranges[j].start = | |
1177 | mem->ranges[j+1].start; | |
1178 | mem->ranges[j].end = | |
1179 | mem->ranges[j+1].end; | |
1180 | } | |
a2e9a95d LJ |
1181 | |
1182 | /* | |
1183 | * Continue to check if there are another overlapping ranges | |
1184 | * from the current position because of shifting the above | |
1185 | * mem ranges. | |
1186 | */ | |
1187 | i--; | |
1188 | mem->nr_ranges--; | |
1189 | continue; | |
babac4a8 AT |
1190 | } |
1191 | mem->nr_ranges--; | |
1192 | return 0; | |
1193 | } | |
1194 | ||
a2e9a95d | 1195 | if (p_start > start && p_end < end) { |
babac4a8 | 1196 | /* Split original range */ |
a2e9a95d LJ |
1197 | mem->ranges[i].end = p_start - 1; |
1198 | temp_range.start = p_end + 1; | |
babac4a8 | 1199 | temp_range.end = end; |
a2e9a95d LJ |
1200 | } else if (p_start != start) |
1201 | mem->ranges[i].end = p_start - 1; | |
babac4a8 | 1202 | else |
a2e9a95d | 1203 | mem->ranges[i].start = p_end + 1; |
babac4a8 AT |
1204 | break; |
1205 | } | |
1206 | ||
1207 | /* If a split happened, add the split to array */ | |
1208 | if (!temp_range.end) | |
1209 | return 0; | |
1210 | ||
1211 | /* Split happened */ | |
1212 | if (i == mem->max_nr_ranges - 1) | |
1213 | return -ENOMEM; | |
1214 | ||
1215 | /* Location where new range should go */ | |
1216 | j = i + 1; | |
1217 | if (j < mem->nr_ranges) { | |
1218 | /* Move over all ranges one slot towards the end */ | |
1219 | for (i = mem->nr_ranges - 1; i >= j; i--) | |
1220 | mem->ranges[i + 1] = mem->ranges[i]; | |
1221 | } | |
1222 | ||
1223 | mem->ranges[j].start = temp_range.start; | |
1224 | mem->ranges[j].end = temp_range.end; | |
1225 | mem->nr_ranges++; | |
1226 | return 0; | |
1227 | } | |
1228 | ||
4853f68d | 1229 | int crash_prepare_elf64_headers(struct crash_mem *mem, int need_kernel_map, |
babac4a8 AT |
1230 | void **addr, unsigned long *sz) |
1231 | { | |
1232 | Elf64_Ehdr *ehdr; | |
1233 | Elf64_Phdr *phdr; | |
1234 | unsigned long nr_cpus = num_possible_cpus(), nr_phdr, elf_sz; | |
1235 | unsigned char *buf; | |
1236 | unsigned int cpu, i; | |
1237 | unsigned long long notes_addr; | |
1238 | unsigned long mstart, mend; | |
1239 | ||
475f63ae | 1240 | /* extra phdr for vmcoreinfo ELF note */ |
babac4a8 AT |
1241 | nr_phdr = nr_cpus + 1; |
1242 | nr_phdr += mem->nr_ranges; | |
1243 | ||
1244 | /* | |
1245 | * kexec-tools creates an extra PT_LOAD phdr for kernel text mapping | |
1246 | * area (for example, ffffffff80000000 - ffffffffa0000000 on x86_64). | |
1247 | * I think this is required by tools like gdb. So same physical | |
475f63ae | 1248 | * memory will be mapped in two ELF headers. One will contain kernel |
babac4a8 AT |
1249 | * text virtual addresses and other will have __va(physical) addresses. |
1250 | */ | |
1251 | ||
1252 | nr_phdr++; | |
1253 | elf_sz = sizeof(Elf64_Ehdr) + nr_phdr * sizeof(Elf64_Phdr); | |
1254 | elf_sz = ALIGN(elf_sz, ELF_CORE_HEADER_ALIGN); | |
1255 | ||
1256 | buf = vzalloc(elf_sz); | |
1257 | if (!buf) | |
1258 | return -ENOMEM; | |
1259 | ||
1260 | ehdr = (Elf64_Ehdr *)buf; | |
1261 | phdr = (Elf64_Phdr *)(ehdr + 1); | |
1262 | memcpy(ehdr->e_ident, ELFMAG, SELFMAG); | |
1263 | ehdr->e_ident[EI_CLASS] = ELFCLASS64; | |
1264 | ehdr->e_ident[EI_DATA] = ELFDATA2LSB; | |
1265 | ehdr->e_ident[EI_VERSION] = EV_CURRENT; | |
1266 | ehdr->e_ident[EI_OSABI] = ELF_OSABI; | |
1267 | memset(ehdr->e_ident + EI_PAD, 0, EI_NIDENT - EI_PAD); | |
1268 | ehdr->e_type = ET_CORE; | |
1269 | ehdr->e_machine = ELF_ARCH; | |
1270 | ehdr->e_version = EV_CURRENT; | |
1271 | ehdr->e_phoff = sizeof(Elf64_Ehdr); | |
1272 | ehdr->e_ehsize = sizeof(Elf64_Ehdr); | |
1273 | ehdr->e_phentsize = sizeof(Elf64_Phdr); | |
1274 | ||
a2e9a95d | 1275 | /* Prepare one phdr of type PT_NOTE for each present CPU */ |
babac4a8 AT |
1276 | for_each_present_cpu(cpu) { |
1277 | phdr->p_type = PT_NOTE; | |
1278 | notes_addr = per_cpu_ptr_to_phys(per_cpu_ptr(crash_notes, cpu)); | |
1279 | phdr->p_offset = phdr->p_paddr = notes_addr; | |
1280 | phdr->p_filesz = phdr->p_memsz = sizeof(note_buf_t); | |
1281 | (ehdr->e_phnum)++; | |
1282 | phdr++; | |
1283 | } | |
1284 | ||
1285 | /* Prepare one PT_NOTE header for vmcoreinfo */ | |
1286 | phdr->p_type = PT_NOTE; | |
1287 | phdr->p_offset = phdr->p_paddr = paddr_vmcoreinfo_note(); | |
1288 | phdr->p_filesz = phdr->p_memsz = VMCOREINFO_NOTE_SIZE; | |
1289 | (ehdr->e_phnum)++; | |
1290 | phdr++; | |
1291 | ||
1292 | /* Prepare PT_LOAD type program header for kernel text region */ | |
4853f68d | 1293 | if (need_kernel_map) { |
babac4a8 AT |
1294 | phdr->p_type = PT_LOAD; |
1295 | phdr->p_flags = PF_R|PF_W|PF_X; | |
f973cce0 | 1296 | phdr->p_vaddr = (unsigned long) _text; |
babac4a8 AT |
1297 | phdr->p_filesz = phdr->p_memsz = _end - _text; |
1298 | phdr->p_offset = phdr->p_paddr = __pa_symbol(_text); | |
1299 | ehdr->e_phnum++; | |
1300 | phdr++; | |
1301 | } | |
1302 | ||
1303 | /* Go through all the ranges in mem->ranges[] and prepare phdr */ | |
1304 | for (i = 0; i < mem->nr_ranges; i++) { | |
1305 | mstart = mem->ranges[i].start; | |
1306 | mend = mem->ranges[i].end; | |
1307 | ||
1308 | phdr->p_type = PT_LOAD; | |
1309 | phdr->p_flags = PF_R|PF_W|PF_X; | |
1310 | phdr->p_offset = mstart; | |
1311 | ||
1312 | phdr->p_paddr = mstart; | |
f973cce0 | 1313 | phdr->p_vaddr = (unsigned long) __va(mstart); |
babac4a8 AT |
1314 | phdr->p_filesz = phdr->p_memsz = mend - mstart + 1; |
1315 | phdr->p_align = 0; | |
1316 | ehdr->e_phnum++; | |
475f63ae | 1317 | 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", |
babac4a8 AT |
1318 | phdr, phdr->p_vaddr, phdr->p_paddr, phdr->p_filesz, |
1319 | ehdr->e_phnum, phdr->p_offset); | |
475f63ae | 1320 | phdr++; |
babac4a8 AT |
1321 | } |
1322 | ||
1323 | *addr = buf; | |
1324 | *sz = elf_sz; | |
1325 | return 0; | |
1326 | } |