kernel/kexec_file.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  * kexec: kexec_file_load system call
   4  *
   5  * Copyright (C) 2014 Red Hat Inc.
   6  * Authors:
   7  *      Vivek Goyal <vgoyal@redhat.com>
   8  */
   9
  10 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
  11
  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>
  17 #include <linux/memblock.h>
  18 #include <linux/mutex.h>
  19 #include <linux/list.h>
  20 #include <linux/fs.h>
  21 #include <linux/ima.h>
  22 #include <crypto/hash.h>
  23 #include <crypto/sha.h>
  24 #include <linux/elf.h>
  25 #include <linux/elfcore.h>
  26 #include <linux/kernel.h>
  27 #include <linux/syscalls.h>
  28 #include <linux/vmalloc.h>
  29 #include "kexec_internal.h"
  30
  31 static int kexec_calculate_store_digests(struct kimage *image);
  32
  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
  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 {
  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);
  71 }
  72
  73 void * __weak arch_kexec_kernel_image_load(struct kimage *image)
  74 {
  75         return kexec_image_load_default(image);
  76 }
  77
  78 int kexec_image_post_load_cleanup_default(struct kimage *image)
  79 {
  80         if (!image->fops || !image->fops->cleanup)
  81                 return 0;
  82
  83         return image->fops->cleanup(image->image_loader_data);
  84 }
  85
  86 int __weak arch_kimage_file_post_load_cleanup(struct kimage *image)
  87 {
  88         return kexec_image_post_load_cleanup_default(image);
  89 }
  90
  91 #ifdef CONFIG_KEXEC_SIG
  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
 103 int __weak arch_kexec_kernel_verify_sig(struct kimage *image, void *buf,
 104                                         unsigned long buf_len)
 105 {
 106         return kexec_image_verify_sig_default(image, buf, buf_len);
 107 }
 108 #endif
 109
 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  */
 119 int __weak
 120 arch_kexec_apply_relocations_add(struct purgatory_info *pi, Elf_Shdr *section,
 121                                  const Elf_Shdr *relsec, const Elf_Shdr *symtab)
 122 {
 123         pr_err("RELA relocation unsupported.\n");
 124         return -ENOEXEC;
 125 }
 126
 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  */
 136 int __weak
 137 arch_kexec_apply_relocations(struct purgatory_info *pi, Elf_Shdr *section,
 138                              const Elf_Shdr *relsec, const Elf_Shdr *symtab)
 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 #ifdef CONFIG_KEXEC_SIG
 181 static int
 182 kimage_validate_signature(struct kimage *image)
 183 {
 184         int ret;
 185
 186         ret = arch_kexec_kernel_verify_sig(image, image->kernel_buf,
 187                                            image->kernel_buf_len);
 188         if (ret) {
 189
 190                 if (IS_ENABLED(CONFIG_KEXEC_SIG_FORCE)) {
 191                         pr_notice("Enforced kernel signature verification failed (%d).\n", ret);
 192                         return ret;
 193                 }
 194
 195                 /*
 196                  * If IMA is guaranteed to appraise a signature on the kexec
 197                  * image, permit it even if the kernel is otherwise locked
 198                  * down.
 199                  */
 200                 if (!ima_appraise_signature(READING_KEXEC_IMAGE) &&
 201                     security_locked_down(LOCKDOWN_KEXEC))
 202                         return -EPERM;
 203
 204                 pr_debug("kernel signature verification failed (%d).\n", ret);
 205         }
 206
 207         return 0;
 208 }
 209 #endif
 210
 211 /*
 212  * In file mode list of segments is prepared by kernel. Copy relevant
 213  * data from user space, do error checking, prepare segment list
 214  */
 215 static int
 216 kimage_file_prepare_segments(struct kimage *image, int kernel_fd, int initrd_fd,
 217                              const char __user *cmdline_ptr,
 218                              unsigned long cmdline_len, unsigned flags)
 219 {
 220         int ret;
 221         void *ldata;
 222         loff_t size;
 223
 224         ret = kernel_read_file_from_fd(kernel_fd, &image->kernel_buf,
 225                                        &size, INT_MAX, READING_KEXEC_IMAGE);
 226         if (ret)
 227                 return ret;
 228         image->kernel_buf_len = size;
 229
 230         /* Call arch image probe handlers */
 231         ret = arch_kexec_kernel_image_probe(image, image->kernel_buf,
 232                                             image->kernel_buf_len);
 233         if (ret)
 234                 goto out;
 235
 236 #ifdef CONFIG_KEXEC_SIG
 237         ret = kimage_validate_signature(image);
 238
 239         if (ret)
 240                 goto out;
 241 #endif
 242         /* It is possible that there no initramfs is being loaded */
 243         if (!(flags & KEXEC_FILE_NO_INITRAMFS)) {
 244                 ret = kernel_read_file_from_fd(initrd_fd, &image->initrd_buf,
 245                                                &size, INT_MAX,
 246                                                READING_KEXEC_INITRAMFS);
 247                 if (ret)
 248                         goto out;
 249                 image->initrd_buf_len = size;
 250         }
 251
 252         if (cmdline_len) {
 253                 image->cmdline_buf = memdup_user(cmdline_ptr, cmdline_len);
 254                 if (IS_ERR(image->cmdline_buf)) {
 255                         ret = PTR_ERR(image->cmdline_buf);
 256                         image->cmdline_buf = NULL;
 257                         goto out;
 258                 }
 259
 260                 image->cmdline_buf_len = cmdline_len;
 261
 262                 /* command line should be a string with last byte null */
 263                 if (image->cmdline_buf[cmdline_len - 1] != '\0') {
 264                         ret = -EINVAL;
 265                         goto out;
 266                 }
 267
 268                 ima_kexec_cmdline(kernel_fd, image->cmdline_buf,
 269                                   image->cmdline_buf_len - 1);
 270         }
 271
 272         /* IMA needs to pass the measurement list to the next kernel. */
 273         ima_add_kexec_buffer(image);
 274
 275         /* Call arch image load handlers */
 276         ldata = arch_kexec_kernel_image_load(image);
 277
 278         if (IS_ERR(ldata)) {
 279                 ret = PTR_ERR(ldata);
 280                 goto out;
 281         }
 282
 283         image->image_loader_data = ldata;
 284 out:
 285         /* In case of error, free up all allocated memory in this function */
 286         if (ret)
 287                 kimage_file_post_load_cleanup(image);
 288         return ret;
 289 }
 290
 291 static int
 292 kimage_file_alloc_init(struct kimage **rimage, int kernel_fd,
 293                        int initrd_fd, const char __user *cmdline_ptr,
 294                        unsigned long cmdline_len, unsigned long flags)
 295 {
 296         int ret;
 297         struct kimage *image;
 298         bool kexec_on_panic = flags & KEXEC_FILE_ON_CRASH;
 299
 300         image = do_kimage_alloc_init();
 301         if (!image)
 302                 return -ENOMEM;
 303
 304         image->file_mode = 1;
 305
 306         if (kexec_on_panic) {
 307                 /* Enable special crash kernel control page alloc policy. */
 308                 image->control_page = crashk_res.start;
 309                 image->type = KEXEC_TYPE_CRASH;
 310         }
 311
 312         ret = kimage_file_prepare_segments(image, kernel_fd, initrd_fd,
 313                                            cmdline_ptr, cmdline_len, flags);
 314         if (ret)
 315                 goto out_free_image;
 316
 317         ret = sanity_check_segment_list(image);
 318         if (ret)
 319                 goto out_free_post_load_bufs;
 320
 321         ret = -ENOMEM;
 322         image->control_code_page = kimage_alloc_control_pages(image,
 323                                            get_order(KEXEC_CONTROL_PAGE_SIZE));
 324         if (!image->control_code_page) {
 325                 pr_err("Could not allocate control_code_buffer\n");
 326                 goto out_free_post_load_bufs;
 327         }
 328
 329         if (!kexec_on_panic) {
 330                 image->swap_page = kimage_alloc_control_pages(image, 0);
 331                 if (!image->swap_page) {
 332                         pr_err("Could not allocate swap buffer\n");
 333                         goto out_free_control_pages;
 334                 }
 335         }
 336
 337         *rimage = image;
 338         return 0;
 339 out_free_control_pages:
 340         kimage_free_page_list(&image->control_pages);
 341 out_free_post_load_bufs:
 342         kimage_file_post_load_cleanup(image);
 343 out_free_image:
 344         kfree(image);
 345         return ret;
 346 }
 347
 348 SYSCALL_DEFINE5(kexec_file_load, int, kernel_fd, int, initrd_fd,
 349                 unsigned long, cmdline_len, const char __user *, cmdline_ptr,
 350                 unsigned long, flags)
 351 {
 352         int ret = 0, i;
 353         struct kimage **dest_image, *image;
 354
 355         /* We only trust the superuser with rebooting the system. */
 356         if (!capable(CAP_SYS_BOOT) || kexec_load_disabled)
 357                 return -EPERM;
 358
 359         /* Make sure we have a legal set of flags */
 360         if (flags != (flags & KEXEC_FILE_FLAGS))
 361                 return -EINVAL;
 362
 363         image = NULL;
 364
 365         if (!mutex_trylock(&kexec_mutex))
 366                 return -EBUSY;
 367
 368         dest_image = &kexec_image;
 369         if (flags & KEXEC_FILE_ON_CRASH) {
 370                 dest_image = &kexec_crash_image;
 371                 if (kexec_crash_image)
 372                         arch_kexec_unprotect_crashkres();
 373         }
 374
 375         if (flags & KEXEC_FILE_UNLOAD)
 376                 goto exchange;
 377
 378         /*
 379          * In case of crash, new kernel gets loaded in reserved region. It is
 380          * same memory where old crash kernel might be loaded. Free any
 381          * current crash dump kernel before we corrupt it.
 382          */
 383         if (flags & KEXEC_FILE_ON_CRASH)
 384                 kimage_free(xchg(&kexec_crash_image, NULL));
 385
 386         ret = kimage_file_alloc_init(&image, kernel_fd, initrd_fd, cmdline_ptr,
 387                                      cmdline_len, flags);
 388         if (ret)
 389                 goto out;
 390
 391         ret = machine_kexec_prepare(image);
 392         if (ret)
 393                 goto out;
 394
 395         /*
 396          * Some architecture(like S390) may touch the crash memory before
 397          * machine_kexec_prepare(), we must copy vmcoreinfo data after it.
 398          */
 399         ret = kimage_crash_copy_vmcoreinfo(image);
 400         if (ret)
 401                 goto out;
 402
 403         ret = kexec_calculate_store_digests(image);
 404         if (ret)
 405                 goto out;
 406
 407         for (i = 0; i < image->nr_segments; i++) {
 408                 struct kexec_segment *ksegment;
 409
 410                 ksegment = &image->segment[i];
 411                 pr_debug("Loading segment %d: buf=0x%p bufsz=0x%zx mem=0x%lx memsz=0x%zx\n",
 412                          i, ksegment->buf, ksegment->bufsz, ksegment->mem,
 413                          ksegment->memsz);
 414
 415                 ret = kimage_load_segment(image, &image->segment[i]);
 416                 if (ret)
 417                         goto out;
 418         }
 419
 420         kimage_terminate(image);
 421
 422         ret = machine_kexec_post_load(image);
 423         if (ret)
 424                 goto out;
 425
 426         /*
 427          * Free up any temporary buffers allocated which are not needed
 428          * after image has been loaded
 429          */
 430         kimage_file_post_load_cleanup(image);
 431 exchange:
 432         image = xchg(dest_image, image);
 433 out:
 434         if ((flags & KEXEC_FILE_ON_CRASH) && kexec_crash_image)
 435                 arch_kexec_protect_crashkres();
 436
 437         mutex_unlock(&kexec_mutex);
 438         kimage_free(image);
 439         return ret;
 440 }
 441
 442 static int locate_mem_hole_top_down(unsigned long start, unsigned long end,
 443                                     struct kexec_buf *kbuf)
 444 {
 445         struct kimage *image = kbuf->image;
 446         unsigned long temp_start, temp_end;
 447
 448         temp_end = min(end, kbuf->buf_max);
 449         temp_start = temp_end - kbuf->memsz;
 450
 451         do {
 452                 /* align down start */
 453                 temp_start = temp_start & (~(kbuf->buf_align - 1));
 454
 455                 if (temp_start < start || temp_start < kbuf->buf_min)
 456                         return 0;
 457
 458                 temp_end = temp_start + kbuf->memsz - 1;
 459
 460                 /*
 461                  * Make sure this does not conflict with any of existing
 462                  * segments
 463                  */
 464                 if (kimage_is_destination_range(image, temp_start, temp_end)) {
 465                         temp_start = temp_start - PAGE_SIZE;
 466                         continue;
 467                 }
 468
 469                 /* We found a suitable memory range */
 470                 break;
 471         } while (1);
 472
 473         /* If we are here, we found a suitable memory range */
 474         kbuf->mem = temp_start;
 475
 476         /* Success, stop navigating through remaining System RAM ranges */
 477         return 1;
 478 }
 479
 480 static int locate_mem_hole_bottom_up(unsigned long start, unsigned long end,
 481                                      struct kexec_buf *kbuf)
 482 {
 483         struct kimage *image = kbuf->image;
 484         unsigned long temp_start, temp_end;
 485
 486         temp_start = max(start, kbuf->buf_min);
 487
 488         do {
 489                 temp_start = ALIGN(temp_start, kbuf->buf_align);
 490                 temp_end = temp_start + kbuf->memsz - 1;
 491
 492                 if (temp_end > end || temp_end > kbuf->buf_max)
 493                         return 0;
 494                 /*
 495                  * Make sure this does not conflict with any of existing
 496                  * segments
 497                  */
 498                 if (kimage_is_destination_range(image, temp_start, temp_end)) {
 499                         temp_start = temp_start + PAGE_SIZE;
 500                         continue;
 501                 }
 502
 503                 /* We found a suitable memory range */
 504                 break;
 505         } while (1);
 506
 507         /* If we are here, we found a suitable memory range */
 508         kbuf->mem = temp_start;
 509
 510         /* Success, stop navigating through remaining System RAM ranges */
 511         return 1;
 512 }
 513
 514 static int locate_mem_hole_callback(struct resource *res, void *arg)
 515 {
 516         struct kexec_buf *kbuf = (struct kexec_buf *)arg;
 517         u64 start = res->start, end = res->end;
 518         unsigned long sz = end - start + 1;
 519
 520         /* Returning 0 will take to next memory range */
 521
 522         /* Don't use memory that will be detected and handled by a driver. */
 523         if (res->flags & IORESOURCE_MEM_DRIVER_MANAGED)
 524                 return 0;
 525
 526         if (sz < kbuf->memsz)
 527                 return 0;
 528
 529         if (end < kbuf->buf_min || start > kbuf->buf_max)
 530                 return 0;
 531
 532         /*
 533          * Allocate memory top down with-in ram range. Otherwise bottom up
 534          * allocation.
 535          */
 536         if (kbuf->top_down)
 537                 return locate_mem_hole_top_down(start, end, kbuf);
 538         return locate_mem_hole_bottom_up(start, end, kbuf);
 539 }
 540
 541 #ifdef CONFIG_ARCH_KEEP_MEMBLOCK
 542 static int kexec_walk_memblock(struct kexec_buf *kbuf,
 543                                int (*func)(struct resource *, void *))
 544 {
 545         int ret = 0;
 546         u64 i;
 547         phys_addr_t mstart, mend;
 548         struct resource res = { };
 549
 550         if (kbuf->image->type == KEXEC_TYPE_CRASH)
 551                 return func(&crashk_res, kbuf);
 552
 553         if (kbuf->top_down) {
 554                 for_each_free_mem_range_reverse(i, NUMA_NO_NODE, MEMBLOCK_NONE,
 555                                                 &mstart, &mend, NULL) {
 556                         /*
 557                          * In memblock, end points to the first byte after the
 558                          * range while in kexec, end points to the last byte
 559                          * in the range.
 560                          */
 561                         res.start = mstart;
 562                         res.end = mend - 1;
 563                         ret = func(&res, kbuf);
 564                         if (ret)
 565                                 break;
 566                 }
 567         } else {
 568                 for_each_free_mem_range(i, NUMA_NO_NODE, MEMBLOCK_NONE,
 569                                         &mstart, &mend, NULL) {
 570                         /*
 571                          * In memblock, end points to the first byte after the
 572                          * range while in kexec, end points to the last byte
 573                          * in the range.
 574                          */
 575                         res.start = mstart;
 576                         res.end = mend - 1;
 577                         ret = func(&res, kbuf);
 578                         if (ret)
 579                                 break;
 580                 }
 581         }
 582
 583         return ret;
 584 }
 585 #else
 586 static int kexec_walk_memblock(struct kexec_buf *kbuf,
 587                                int (*func)(struct resource *, void *))
 588 {
 589         return 0;
 590 }
 591 #endif
 592
 593 /**
 594  * kexec_walk_resources - call func(data) on free memory regions
 595  * @kbuf:       Context info for the search. Also passed to @func.
 596  * @func:       Function to call for each memory region.
 597  *
 598  * Return: The memory walk will stop when func returns a non-zero value
 599  * and that value will be returned. If all free regions are visited without
 600  * func returning non-zero, then zero will be returned.
 601  */
 602 static int kexec_walk_resources(struct kexec_buf *kbuf,
 603                                 int (*func)(struct resource *, void *))
 604 {
 605         if (kbuf->image->type == KEXEC_TYPE_CRASH)
 606                 return walk_iomem_res_desc(crashk_res.desc,
 607                                            IORESOURCE_SYSTEM_RAM | IORESOURCE_BUSY,
 608                                            crashk_res.start, crashk_res.end,
 609                                            kbuf, func);
 610         else
 611                 return walk_system_ram_res(0, ULONG_MAX, kbuf, func);
 612 }
 613
 614 /**
 615  * kexec_locate_mem_hole - find free memory for the purgatory or the next kernel
 616  * @kbuf:       Parameters for the memory search.
 617  *
 618  * On success, kbuf->mem will have the start address of the memory region found.
 619  *
 620  * Return: 0 on success, negative errno on error.
 621  */
 622 int kexec_locate_mem_hole(struct kexec_buf *kbuf)
 623 {
 624         int ret;
 625
 626         /* Arch knows where to place */
 627         if (kbuf->mem != KEXEC_BUF_MEM_UNKNOWN)
 628                 return 0;
 629
 630         if (!IS_ENABLED(CONFIG_ARCH_KEEP_MEMBLOCK))
 631                 ret = kexec_walk_resources(kbuf, locate_mem_hole_callback);
 632         else
 633                 ret = kexec_walk_memblock(kbuf, locate_mem_hole_callback);
 634
 635         return ret == 1 ? 0 : -EADDRNOTAVAIL;
 636 }
 637
 638 /**
 639  * arch_kexec_locate_mem_hole - Find free memory to place the segments.
 640  * @kbuf:                       Parameters for the memory search.
 641  *
 642  * On success, kbuf->mem will have the start address of the memory region found.
 643  *
 644  * Return: 0 on success, negative errno on error.
 645  */
 646 int __weak arch_kexec_locate_mem_hole(struct kexec_buf *kbuf)
 647 {
 648         return kexec_locate_mem_hole(kbuf);
 649 }
 650
 651 /**
 652  * kexec_add_buffer - place a buffer in a kexec segment
 653  * @kbuf:       Buffer contents and memory parameters.
 654  *
 655  * This function assumes that kexec_mutex is held.
 656  * On successful return, @kbuf->mem will have the physical address of
 657  * the buffer in memory.
 658  *
 659  * Return: 0 on success, negative errno on error.
 660  */
 661 int kexec_add_buffer(struct kexec_buf *kbuf)
 662 {
 663         struct kexec_segment *ksegment;
 664         int ret;
 665
 666         /* Currently adding segment this way is allowed only in file mode */
 667         if (!kbuf->image->file_mode)
 668                 return -EINVAL;
 669
 670         if (kbuf->image->nr_segments >= KEXEC_SEGMENT_MAX)
 671                 return -EINVAL;
 672
 673         /*
 674          * Make sure we are not trying to add buffer after allocating
 675          * control pages. All segments need to be placed first before
 676          * any control pages are allocated. As control page allocation
 677          * logic goes through list of segments to make sure there are
 678          * no destination overlaps.
 679          */
 680         if (!list_empty(&kbuf->image->control_pages)) {
 681                 WARN_ON(1);
 682                 return -EINVAL;
 683         }
 684
 685         /* Ensure minimum alignment needed for segments. */
 686         kbuf->memsz = ALIGN(kbuf->memsz, PAGE_SIZE);
 687         kbuf->buf_align = max(kbuf->buf_align, PAGE_SIZE);
 688
 689         /* Walk the RAM ranges and allocate a suitable range for the buffer */
 690         ret = arch_kexec_locate_mem_hole(kbuf);
 691         if (ret)
 692                 return ret;
 693
 694         /* Found a suitable memory range */
 695         ksegment = &kbuf->image->segment[kbuf->image->nr_segments];
 696         ksegment->kbuf = kbuf->buffer;
 697         ksegment->bufsz = kbuf->bufsz;
 698         ksegment->mem = kbuf->mem;
 699         ksegment->memsz = kbuf->memsz;
 700         kbuf->image->nr_segments++;
 701         return 0;
 702 }
 703
 704 /* Calculate and store the digest of segments */
 705 static int kexec_calculate_store_digests(struct kimage *image)
 706 {
 707         struct crypto_shash *tfm;
 708         struct shash_desc *desc;
 709         int ret = 0, i, j, zero_buf_sz, sha_region_sz;
 710         size_t desc_size, nullsz;
 711         char *digest;
 712         void *zero_buf;
 713         struct kexec_sha_region *sha_regions;
 714         struct purgatory_info *pi = &image->purgatory_info;
 715
 716         if (!IS_ENABLED(CONFIG_ARCH_HAS_KEXEC_PURGATORY))
 717                 return 0;
 718
 719         zero_buf = __va(page_to_pfn(ZERO_PAGE(0)) << PAGE_SHIFT);
 720         zero_buf_sz = PAGE_SIZE;
 721
 722         tfm = crypto_alloc_shash("sha256", 0, 0);
 723         if (IS_ERR(tfm)) {
 724                 ret = PTR_ERR(tfm);
 725                 goto out;
 726         }
 727
 728         desc_size = crypto_shash_descsize(tfm) + sizeof(*desc);
 729         desc = kzalloc(desc_size, GFP_KERNEL);
 730         if (!desc) {
 731                 ret = -ENOMEM;
 732                 goto out_free_tfm;
 733         }
 734
 735         sha_region_sz = KEXEC_SEGMENT_MAX * sizeof(struct kexec_sha_region);
 736         sha_regions = vzalloc(sha_region_sz);
 737         if (!sha_regions)
 738                 goto out_free_desc;
 739
 740         desc->tfm   = tfm;
 741
 742         ret = crypto_shash_init(desc);
 743         if (ret < 0)
 744                 goto out_free_sha_regions;
 745
 746         digest = kzalloc(SHA256_DIGEST_SIZE, GFP_KERNEL);
 747         if (!digest) {
 748                 ret = -ENOMEM;
 749                 goto out_free_sha_regions;
 750         }
 751
 752         for (j = i = 0; i < image->nr_segments; i++) {
 753                 struct kexec_segment *ksegment;
 754
 755                 ksegment = &image->segment[i];
 756                 /*
 757                  * Skip purgatory as it will be modified once we put digest
 758                  * info in purgatory.
 759                  */
 760                 if (ksegment->kbuf == pi->purgatory_buf)
 761                         continue;
 762
 763                 ret = crypto_shash_update(desc, ksegment->kbuf,
 764                                           ksegment->bufsz);
 765                 if (ret)
 766                         break;
 767
 768                 /*
 769                  * Assume rest of the buffer is filled with zero and
 770                  * update digest accordingly.
 771                  */
 772                 nullsz = ksegment->memsz - ksegment->bufsz;
 773                 while (nullsz) {
 774                         unsigned long bytes = nullsz;
 775
 776                         if (bytes > zero_buf_sz)
 777                                 bytes = zero_buf_sz;
 778                         ret = crypto_shash_update(desc, zero_buf, bytes);
 779                         if (ret)
 780                                 break;
 781                         nullsz -= bytes;
 782                 }
 783
 784                 if (ret)
 785                         break;
 786
 787                 sha_regions[j].start = ksegment->mem;
 788                 sha_regions[j].len = ksegment->memsz;
 789                 j++;
 790         }
 791
 792         if (!ret) {
 793                 ret = crypto_shash_final(desc, digest);
 794                 if (ret)
 795                         goto out_free_digest;
 796                 ret = kexec_purgatory_get_set_symbol(image, "purgatory_sha_regions",
 797                                                      sha_regions, sha_region_sz, 0);
 798                 if (ret)
 799                         goto out_free_digest;
 800
 801                 ret = kexec_purgatory_get_set_symbol(image, "purgatory_sha256_digest",
 802                                                      digest, SHA256_DIGEST_SIZE, 0);
 803                 if (ret)
 804                         goto out_free_digest;
 805         }
 806
 807 out_free_digest:
 808         kfree(digest);
 809 out_free_sha_regions:
 810         vfree(sha_regions);
 811 out_free_desc:
 812         kfree(desc);
 813 out_free_tfm:
 814         kfree(tfm);
 815 out:
 816         return ret;
 817 }
 818
 819 #ifdef CONFIG_ARCH_HAS_KEXEC_PURGATORY
 820 /*
 821  * kexec_purgatory_setup_kbuf - prepare buffer to load purgatory.
 822  * @pi:         Purgatory to be loaded.
 823  * @kbuf:       Buffer to setup.
 824  *
 825  * Allocates the memory needed for the buffer. Caller is responsible to free
 826  * the memory after use.
 827  *
 828  * Return: 0 on success, negative errno on error.
 829  */
 830 static int kexec_purgatory_setup_kbuf(struct purgatory_info *pi,
 831                                       struct kexec_buf *kbuf)
 832 {
 833         const Elf_Shdr *sechdrs;
 834         unsigned long bss_align;
 835         unsigned long bss_sz;
 836         unsigned long align;
 837         int i, ret;
 838
 839         sechdrs = (void *)pi->ehdr + pi->ehdr->e_shoff;
 840         kbuf->buf_align = bss_align = 1;
 841         kbuf->bufsz = bss_sz = 0;
 842
 843         for (i = 0; i < pi->ehdr->e_shnum; i++) {
 844                 if (!(sechdrs[i].sh_flags & SHF_ALLOC))
 845                         continue;
 846
 847                 align = sechdrs[i].sh_addralign;
 848                 if (sechdrs[i].sh_type != SHT_NOBITS) {
 849                         if (kbuf->buf_align < align)
 850                                 kbuf->buf_align = align;
 851                         kbuf->bufsz = ALIGN(kbuf->bufsz, align);
 852                         kbuf->bufsz += sechdrs[i].sh_size;
 853                 } else {
 854                         if (bss_align < align)
 855                                 bss_align = align;
 856                         bss_sz = ALIGN(bss_sz, align);
 857                         bss_sz += sechdrs[i].sh_size;
 858                 }
 859         }
 860         kbuf->bufsz = ALIGN(kbuf->bufsz, bss_align);
 861         kbuf->memsz = kbuf->bufsz + bss_sz;
 862         if (kbuf->buf_align < bss_align)
 863                 kbuf->buf_align = bss_align;
 864
 865         kbuf->buffer = vzalloc(kbuf->bufsz);
 866         if (!kbuf->buffer)
 867                 return -ENOMEM;
 868         pi->purgatory_buf = kbuf->buffer;
 869
 870         ret = kexec_add_buffer(kbuf);
 871         if (ret)
 872                 goto out;
 873
 874         return 0;
 875 out:
 876         vfree(pi->purgatory_buf);
 877         pi->purgatory_buf = NULL;
 878         return ret;
 879 }
 880
 881 /*
 882  * kexec_purgatory_setup_sechdrs - prepares the pi->sechdrs buffer.
 883  * @pi:         Purgatory to be loaded.
 884  * @kbuf:       Buffer prepared to store purgatory.
 885  *
 886  * Allocates the memory needed for the buffer. Caller is responsible to free
 887  * the memory after use.
 888  *
 889  * Return: 0 on success, negative errno on error.
 890  */
 891 static int kexec_purgatory_setup_sechdrs(struct purgatory_info *pi,
 892                                          struct kexec_buf *kbuf)
 893 {
 894         unsigned long bss_addr;
 895         unsigned long offset;
 896         Elf_Shdr *sechdrs;
 897         int i;
 898
 899         /*
 900          * The section headers in kexec_purgatory are read-only. In order to
 901          * have them modifiable make a temporary copy.
 902          */
 903         sechdrs = vzalloc(array_size(sizeof(Elf_Shdr), pi->ehdr->e_shnum));
 904         if (!sechdrs)
 905                 return -ENOMEM;
 906         memcpy(sechdrs, (void *)pi->ehdr + pi->ehdr->e_shoff,
 907                pi->ehdr->e_shnum * sizeof(Elf_Shdr));
 908         pi->sechdrs = sechdrs;
 909
 910         offset = 0;
 911         bss_addr = kbuf->mem + kbuf->bufsz;
 912         kbuf->image->start = pi->ehdr->e_entry;
 913
 914         for (i = 0; i < pi->ehdr->e_shnum; i++) {
 915                 unsigned long align;
 916                 void *src, *dst;
 917
 918                 if (!(sechdrs[i].sh_flags & SHF_ALLOC))
 919                         continue;
 920
 921                 align = sechdrs[i].sh_addralign;
 922                 if (sechdrs[i].sh_type == SHT_NOBITS) {
 923                         bss_addr = ALIGN(bss_addr, align);
 924                         sechdrs[i].sh_addr = bss_addr;
 925                         bss_addr += sechdrs[i].sh_size;
 926                         continue;
 927                 }
 928
 929                 offset = ALIGN(offset, align);
 930                 if (sechdrs[i].sh_flags & SHF_EXECINSTR &&
 931                     pi->ehdr->e_entry >= sechdrs[i].sh_addr &&
 932                     pi->ehdr->e_entry < (sechdrs[i].sh_addr
 933                                          + sechdrs[i].sh_size)) {
 934                         kbuf->image->start -= sechdrs[i].sh_addr;
 935                         kbuf->image->start += kbuf->mem + offset;
 936                 }
 937
 938                 src = (void *)pi->ehdr + sechdrs[i].sh_offset;
 939                 dst = pi->purgatory_buf + offset;
 940                 memcpy(dst, src, sechdrs[i].sh_size);
 941
 942                 sechdrs[i].sh_addr = kbuf->mem + offset;
 943                 sechdrs[i].sh_offset = offset;
 944                 offset += sechdrs[i].sh_size;
 945         }
 946
 947         return 0;
 948 }
 949
 950 static int kexec_apply_relocations(struct kimage *image)
 951 {
 952         int i, ret;
 953         struct purgatory_info *pi = &image->purgatory_info;
 954         const Elf_Shdr *sechdrs;
 955
 956         sechdrs = (void *)pi->ehdr + pi->ehdr->e_shoff;
 957
 958         for (i = 0; i < pi->ehdr->e_shnum; i++) {
 959                 const Elf_Shdr *relsec;
 960                 const Elf_Shdr *symtab;
 961                 Elf_Shdr *section;
 962
 963                 relsec = sechdrs + i;
 964
 965                 if (relsec->sh_type != SHT_RELA &&
 966                     relsec->sh_type != SHT_REL)
 967                         continue;
 968
 969                 /*
 970                  * For section of type SHT_RELA/SHT_REL,
 971                  * ->sh_link contains section header index of associated
 972                  * symbol table. And ->sh_info contains section header
 973                  * index of section to which relocations apply.
 974                  */
 975                 if (relsec->sh_info >= pi->ehdr->e_shnum ||
 976                     relsec->sh_link >= pi->ehdr->e_shnum)
 977                         return -ENOEXEC;
 978
 979                 section = pi->sechdrs + relsec->sh_info;
 980                 symtab = sechdrs + relsec->sh_link;
 981
 982                 if (!(section->sh_flags & SHF_ALLOC))
 983                         continue;
 984
 985                 /*
 986                  * symtab->sh_link contain section header index of associated
 987                  * string table.
 988                  */
 989                 if (symtab->sh_link >= pi->ehdr->e_shnum)
 990                         /* Invalid section number? */
 991                         continue;
 992
 993                 /*
 994                  * Respective architecture needs to provide support for applying
 995                  * relocations of type SHT_RELA/SHT_REL.
 996                  */
 997                 if (relsec->sh_type == SHT_RELA)
 998                         ret = arch_kexec_apply_relocations_add(pi, section,
 999                                                                relsec, symtab);
1000                 else if (relsec->sh_type == SHT_REL)
1001                         ret = arch_kexec_apply_relocations(pi, section,
1002                                                            relsec, symtab);
1003                 if (ret)
1004                         return ret;
1005         }
1006
1007         return 0;
1008 }
1009
1010 /*
1011  * kexec_load_purgatory - Load and relocate the purgatory object.
1012  * @image:      Image to add the purgatory to.
1013  * @kbuf:       Memory parameters to use.
1014  *
1015  * Allocates the memory needed for image->purgatory_info.sechdrs and
1016  * image->purgatory_info.purgatory_buf/kbuf->buffer. Caller is responsible
1017  * to free the memory after use.
1018  *
1019  * Return: 0 on success, negative errno on error.
1020  */
1021 int kexec_load_purgatory(struct kimage *image, struct kexec_buf *kbuf)
1022 {
1023         struct purgatory_info *pi = &image->purgatory_info;
1024         int ret;
1025
1026         if (kexec_purgatory_size <= 0)
1027                 return -EINVAL;
1028
1029         pi->ehdr = (const Elf_Ehdr *)kexec_purgatory;
1030
1031         ret = kexec_purgatory_setup_kbuf(pi, kbuf);
1032         if (ret)
1033                 return ret;
1034
1035         ret = kexec_purgatory_setup_sechdrs(pi, kbuf);
1036         if (ret)
1037                 goto out_free_kbuf;
1038
1039         ret = kexec_apply_relocations(image);
1040         if (ret)
1041                 goto out;
1042
1043         return 0;
1044 out:
1045         vfree(pi->sechdrs);
1046         pi->sechdrs = NULL;
1047 out_free_kbuf:
1048         vfree(pi->purgatory_buf);
1049         pi->purgatory_buf = NULL;
1050         return ret;
1051 }
1052
1053 /*
1054  * kexec_purgatory_find_symbol - find a symbol in the purgatory
1055  * @pi:         Purgatory to search in.
1056  * @name:       Name of the symbol.
1057  *
1058  * Return: pointer to symbol in read-only symtab on success, NULL on error.
1059  */
1060 static const Elf_Sym *kexec_purgatory_find_symbol(struct purgatory_info *pi,
1061                                                   const char *name)
1062 {
1063         const Elf_Shdr *sechdrs;
1064         const Elf_Ehdr *ehdr;
1065         const Elf_Sym *syms;
1066         const char *strtab;
1067         int i, k;
1068
1069         if (!pi->ehdr)
1070                 return NULL;
1071
1072         ehdr = pi->ehdr;
1073         sechdrs = (void *)ehdr + ehdr->e_shoff;
1074
1075         for (i = 0; i < ehdr->e_shnum; i++) {
1076                 if (sechdrs[i].sh_type != SHT_SYMTAB)
1077                         continue;
1078
1079                 if (sechdrs[i].sh_link >= ehdr->e_shnum)
1080                         /* Invalid strtab section number */
1081                         continue;
1082                 strtab = (void *)ehdr + sechdrs[sechdrs[i].sh_link].sh_offset;
1083                 syms = (void *)ehdr + sechdrs[i].sh_offset;
1084
1085                 /* Go through symbols for a match */
1086                 for (k = 0; k < sechdrs[i].sh_size/sizeof(Elf_Sym); k++) {
1087                         if (ELF_ST_BIND(syms[k].st_info) != STB_GLOBAL)
1088                                 continue;
1089
1090                         if (strcmp(strtab + syms[k].st_name, name) != 0)
1091                                 continue;
1092
1093                         if (syms[k].st_shndx == SHN_UNDEF ||
1094                             syms[k].st_shndx >= ehdr->e_shnum) {
1095                                 pr_debug("Symbol: %s has bad section index %d.\n",
1096                                                 name, syms[k].st_shndx);
1097                                 return NULL;
1098                         }
1099
1100                         /* Found the symbol we are looking for */
1101                         return &syms[k];
1102                 }
1103         }
1104
1105         return NULL;
1106 }
1107
1108 void *kexec_purgatory_get_symbol_addr(struct kimage *image, const char *name)
1109 {
1110         struct purgatory_info *pi = &image->purgatory_info;
1111         const Elf_Sym *sym;
1112         Elf_Shdr *sechdr;
1113
1114         sym = kexec_purgatory_find_symbol(pi, name);
1115         if (!sym)
1116                 return ERR_PTR(-EINVAL);
1117
1118         sechdr = &pi->sechdrs[sym->st_shndx];
1119
1120         /*
1121          * Returns the address where symbol will finally be loaded after
1122          * kexec_load_segment()
1123          */
1124         return (void *)(sechdr->sh_addr + sym->st_value);
1125 }
1126
1127 /*
1128  * Get or set value of a symbol. If "get_value" is true, symbol value is
1129  * returned in buf otherwise symbol value is set based on value in buf.
1130  */
1131 int kexec_purgatory_get_set_symbol(struct kimage *image, const char *name,
1132                                    void *buf, unsigned int size, bool get_value)
1133 {
1134         struct purgatory_info *pi = &image->purgatory_info;
1135         const Elf_Sym *sym;
1136         Elf_Shdr *sec;
1137         char *sym_buf;
1138
1139         sym = kexec_purgatory_find_symbol(pi, name);
1140         if (!sym)
1141                 return -EINVAL;
1142
1143         if (sym->st_size != size) {
1144                 pr_err("symbol %s size mismatch: expected %lu actual %u\n",
1145                        name, (unsigned long)sym->st_size, size);
1146                 return -EINVAL;
1147         }
1148
1149         sec = pi->sechdrs + sym->st_shndx;
1150
1151         if (sec->sh_type == SHT_NOBITS) {
1152                 pr_err("symbol %s is in a bss section. Cannot %s\n", name,
1153                        get_value ? "get" : "set");
1154                 return -EINVAL;
1155         }
1156
1157         sym_buf = (char *)pi->purgatory_buf + sec->sh_offset + sym->st_value;
1158
1159         if (get_value)
1160                 memcpy((void *)buf, sym_buf, size);
1161         else
1162                 memcpy((void *)sym_buf, buf, size);
1163
1164         return 0;
1165 }
1166 #endif /* CONFIG_ARCH_HAS_KEXEC_PURGATORY */
1167
1168 int crash_exclude_mem_range(struct crash_mem *mem,
1169                             unsigned long long mstart, unsigned long long mend)
1170 {
1171         int i, j;
1172         unsigned long long start, end, p_start, p_end;
1173         struct crash_mem_range temp_range = {0, 0};
1174
1175         for (i = 0; i < mem->nr_ranges; i++) {
1176                 start = mem->ranges[i].start;
1177                 end = mem->ranges[i].end;
1178                 p_start = mstart;
1179                 p_end = mend;
1180
1181                 if (mstart > end || mend < start)
1182                         continue;
1183
1184                 /* Truncate any area outside of range */
1185                 if (mstart < start)
1186                         p_start = start;
1187                 if (mend > end)
1188                         p_end = end;
1189
1190                 /* Found completely overlapping range */
1191                 if (p_start == start && p_end == end) {
1192                         mem->ranges[i].start = 0;
1193                         mem->ranges[i].end = 0;
1194                         if (i < mem->nr_ranges - 1) {
1195                                 /* Shift rest of the ranges to left */
1196                                 for (j = i; j < mem->nr_ranges - 1; j++) {
1197                                         mem->ranges[j].start =
1198                                                 mem->ranges[j+1].start;
1199                                         mem->ranges[j].end =
1200                                                         mem->ranges[j+1].end;
1201                                 }
1202
1203                                 /*
1204                                  * Continue to check if there are another overlapping ranges
1205                                  * from the current position because of shifting the above
1206                                  * mem ranges.
1207                                  */
1208                                 i--;
1209                                 mem->nr_ranges--;
1210                                 continue;
1211                         }
1212                         mem->nr_ranges--;
1213                         return 0;
1214                 }
1215
1216                 if (p_start > start && p_end < end) {
1217                         /* Split original range */
1218                         mem->ranges[i].end = p_start - 1;
1219                         temp_range.start = p_end + 1;
1220                         temp_range.end = end;
1221                 } else if (p_start != start)
1222                         mem->ranges[i].end = p_start - 1;
1223                 else
1224                         mem->ranges[i].start = p_end + 1;
1225                 break;
1226         }
1227
1228         /* If a split happened, add the split to array */
1229         if (!temp_range.end)
1230                 return 0;
1231
1232         /* Split happened */
1233         if (i == mem->max_nr_ranges - 1)
1234                 return -ENOMEM;
1235
1236         /* Location where new range should go */
1237         j = i + 1;
1238         if (j < mem->nr_ranges) {
1239                 /* Move over all ranges one slot towards the end */
1240                 for (i = mem->nr_ranges - 1; i >= j; i--)
1241                         mem->ranges[i + 1] = mem->ranges[i];
1242         }
1243
1244         mem->ranges[j].start = temp_range.start;
1245         mem->ranges[j].end = temp_range.end;
1246         mem->nr_ranges++;
1247         return 0;
1248 }
1249
1250 int crash_prepare_elf64_headers(struct crash_mem *mem, int kernel_map,
1251                           void **addr, unsigned long *sz)
1252 {
1253         Elf64_Ehdr *ehdr;
1254         Elf64_Phdr *phdr;
1255         unsigned long nr_cpus = num_possible_cpus(), nr_phdr, elf_sz;
1256         unsigned char *buf;
1257         unsigned int cpu, i;
1258         unsigned long long notes_addr;
1259         unsigned long mstart, mend;
1260
1261         /* extra phdr for vmcoreinfo ELF note */
1262         nr_phdr = nr_cpus + 1;
1263         nr_phdr += mem->nr_ranges;
1264
1265         /*
1266          * kexec-tools creates an extra PT_LOAD phdr for kernel text mapping
1267          * area (for example, ffffffff80000000 - ffffffffa0000000 on x86_64).
1268          * I think this is required by tools like gdb. So same physical
1269          * memory will be mapped in two ELF headers. One will contain kernel
1270          * text virtual addresses and other will have __va(physical) addresses.
1271          */
1272
1273         nr_phdr++;
1274         elf_sz = sizeof(Elf64_Ehdr) + nr_phdr * sizeof(Elf64_Phdr);
1275         elf_sz = ALIGN(elf_sz, ELF_CORE_HEADER_ALIGN);
1276
1277         buf = vzalloc(elf_sz);
1278         if (!buf)
1279                 return -ENOMEM;
1280
1281         ehdr = (Elf64_Ehdr *)buf;
1282         phdr = (Elf64_Phdr *)(ehdr + 1);
1283         memcpy(ehdr->e_ident, ELFMAG, SELFMAG);
1284         ehdr->e_ident[EI_CLASS] = ELFCLASS64;
1285         ehdr->e_ident[EI_DATA] = ELFDATA2LSB;
1286         ehdr->e_ident[EI_VERSION] = EV_CURRENT;
1287         ehdr->e_ident[EI_OSABI] = ELF_OSABI;
1288         memset(ehdr->e_ident + EI_PAD, 0, EI_NIDENT - EI_PAD);
1289         ehdr->e_type = ET_CORE;
1290         ehdr->e_machine = ELF_ARCH;
1291         ehdr->e_version = EV_CURRENT;
1292         ehdr->e_phoff = sizeof(Elf64_Ehdr);
1293         ehdr->e_ehsize = sizeof(Elf64_Ehdr);
1294         ehdr->e_phentsize = sizeof(Elf64_Phdr);
1295
1296         /* Prepare one phdr of type PT_NOTE for each present CPU */
1297         for_each_present_cpu(cpu) {
1298                 phdr->p_type = PT_NOTE;
1299                 notes_addr = per_cpu_ptr_to_phys(per_cpu_ptr(crash_notes, cpu));
1300                 phdr->p_offset = phdr->p_paddr = notes_addr;
1301                 phdr->p_filesz = phdr->p_memsz = sizeof(note_buf_t);
1302                 (ehdr->e_phnum)++;
1303                 phdr++;
1304         }
1305
1306         /* Prepare one PT_NOTE header for vmcoreinfo */
1307         phdr->p_type = PT_NOTE;
1308         phdr->p_offset = phdr->p_paddr = paddr_vmcoreinfo_note();
1309         phdr->p_filesz = phdr->p_memsz = VMCOREINFO_NOTE_SIZE;
1310         (ehdr->e_phnum)++;
1311         phdr++;
1312
1313         /* Prepare PT_LOAD type program header for kernel text region */
1314         if (kernel_map) {
1315                 phdr->p_type = PT_LOAD;
1316                 phdr->p_flags = PF_R|PF_W|PF_X;
1317                 phdr->p_vaddr = (unsigned long) _text;
1318                 phdr->p_filesz = phdr->p_memsz = _end - _text;
1319                 phdr->p_offset = phdr->p_paddr = __pa_symbol(_text);
1320                 ehdr->e_phnum++;
1321                 phdr++;
1322         }
1323
1324         /* Go through all the ranges in mem->ranges[] and prepare phdr */
1325         for (i = 0; i < mem->nr_ranges; i++) {
1326                 mstart = mem->ranges[i].start;
1327                 mend = mem->ranges[i].end;
1328
1329                 phdr->p_type = PT_LOAD;
1330                 phdr->p_flags = PF_R|PF_W|PF_X;
1331                 phdr->p_offset  = mstart;
1332
1333                 phdr->p_paddr = mstart;
1334                 phdr->p_vaddr = (unsigned long) __va(mstart);
1335                 phdr->p_filesz = phdr->p_memsz = mend - mstart + 1;
1336                 phdr->p_align = 0;
1337                 ehdr->e_phnum++;
1338                 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",
1339                         phdr, phdr->p_vaddr, phdr->p_paddr, phdr->p_filesz,
1340                         ehdr->e_phnum, phdr->p_offset);
1341                 phdr++;
1342         }
1343
1344         *addr = buf;
1345         *sz = elf_sz;
1346         return 0;
1347 }