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/sha2.h>
  24 #include <linux/elf.h>
  25 #include <linux/elfcore.h>
  26 #include <linux/kernel.h>
  27 #include <linux/kernel_read_file.h>
  28 #include <linux/syscalls.h>
  29 #include <linux/vmalloc.h>
  30 #include "kexec_internal.h"
  31
  32 static int kexec_calculate_store_digests(struct kimage *image);
  33
  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
  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 {
  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);
  72 }
  73
  74 void * __weak arch_kexec_kernel_image_load(struct kimage *image)
  75 {
  76         return kexec_image_load_default(image);
  77 }
  78
  79 int kexec_image_post_load_cleanup_default(struct kimage *image)
  80 {
  81         if (!image->fops || !image->fops->cleanup)
  82                 return 0;
  83
  84         return image->fops->cleanup(image->image_loader_data);
  85 }
  86
  87 int __weak arch_kimage_file_post_load_cleanup(struct kimage *image)
  88 {
  89         return kexec_image_post_load_cleanup_default(image);
  90 }
  91
  92 #ifdef CONFIG_KEXEC_SIG
  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
 104 int __weak arch_kexec_kernel_verify_sig(struct kimage *image, void *buf,
 105                                         unsigned long buf_len)
 106 {
 107         return kexec_image_verify_sig_default(image, buf, buf_len);
 108 }
 109 #endif
 110
 111 /*
 112  * arch_kexec_apply_relocations_add - apply relocations of type RELA
 113  * @pi:         Purgatory to be relocated.
 114  * @section:    Section relocations applying to.
 115  * @relsec:     Section containing RELAs.
 116  * @symtab:     Corresponding symtab.
 117  *
 118  * Return: 0 on success, negative errno on error.
 119  */
 120 int __weak
 121 arch_kexec_apply_relocations_add(struct purgatory_info *pi, Elf_Shdr *section,
 122                                  const Elf_Shdr *relsec, const Elf_Shdr *symtab)
 123 {
 124         pr_err("RELA relocation unsupported.\n");
 125         return -ENOEXEC;
 126 }
 127
 128 /*
 129  * arch_kexec_apply_relocations - apply relocations of type REL
 130  * @pi:         Purgatory to be relocated.
 131  * @section:    Section relocations applying to.
 132  * @relsec:     Section containing RELs.
 133  * @symtab:     Corresponding symtab.
 134  *
 135  * Return: 0 on success, negative errno on error.
 136  */
 137 int __weak
 138 arch_kexec_apply_relocations(struct purgatory_info *pi, Elf_Shdr *section,
 139                              const Elf_Shdr *relsec, const Elf_Shdr *symtab)
 140 {
 141         pr_err("REL relocation unsupported.\n");
 142         return -ENOEXEC;
 143 }
 144
 145 /*
 146  * Free up memory used by kernel, initrd, and command line. This is temporary
 147  * memory allocation which is not needed any more after these buffers have
 148  * been loaded into separate segments and have been copied elsewhere.
 149  */
 150 void kimage_file_post_load_cleanup(struct kimage *image)
 151 {
 152         struct purgatory_info *pi = &image->purgatory_info;
 153
 154         vfree(image->kernel_buf);
 155         image->kernel_buf = NULL;
 156
 157         vfree(image->initrd_buf);
 158         image->initrd_buf = NULL;
 159
 160         kfree(image->cmdline_buf);
 161         image->cmdline_buf = NULL;
 162
 163         vfree(pi->purgatory_buf);
 164         pi->purgatory_buf = NULL;
 165
 166         vfree(pi->sechdrs);
 167         pi->sechdrs = NULL;
 168
 169         /* See if architecture has anything to cleanup post load */
 170         arch_kimage_file_post_load_cleanup(image);
 171
 172         /*
 173          * Above call should have called into bootloader to free up
 174          * any data stored in kimage->image_loader_data. It should
 175          * be ok now to free it up.
 176          */
 177         kfree(image->image_loader_data);
 178         image->image_loader_data = NULL;
 179 }
 180
 181 #ifdef CONFIG_KEXEC_SIG
 182 static int
 183 kimage_validate_signature(struct kimage *image)
 184 {
 185         int ret;
 186
 187         ret = arch_kexec_kernel_verify_sig(image, image->kernel_buf,
 188                                            image->kernel_buf_len);
 189         if (ret) {
 190
 191                 if (IS_ENABLED(CONFIG_KEXEC_SIG_FORCE)) {
 192                         pr_notice("Enforced kernel signature verification failed (%d).\n", ret);
 193                         return ret;
 194                 }
 195
 196                 /*
 197                  * If IMA is guaranteed to appraise a signature on the kexec
 198                  * image, permit it even if the kernel is otherwise locked
 199                  * down.
 200                  */
 201                 if (!ima_appraise_signature(READING_KEXEC_IMAGE) &&
 202                     security_locked_down(LOCKDOWN_KEXEC))
 203                         return -EPERM;
 204
 205                 pr_debug("kernel signature verification failed (%d).\n", ret);
 206         }
 207
 208         return 0;
 209 }
 210 #endif
 211
 212 /*
 213  * In file mode list of segments is prepared by kernel. Copy relevant
 214  * data from user space, do error checking, prepare segment list
 215  */
 216 static int
 217 kimage_file_prepare_segments(struct kimage *image, int kernel_fd, int initrd_fd,
 218                              const char __user *cmdline_ptr,
 219                              unsigned long cmdline_len, unsigned flags)
 220 {
 221         int ret;
 222         void *ldata;
 223
 224         ret = kernel_read_file_from_fd(kernel_fd, 0, &image->kernel_buf,
 225                                        INT_MAX, NULL, READING_KEXEC_IMAGE);
 226         if (ret < 0)
 227                 return ret;
 228         image->kernel_buf_len = ret;
 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, 0, &image->initrd_buf,
 245                                                INT_MAX, NULL,
 246                                                READING_KEXEC_INITRAMFS);
 247                 if (ret < 0)
 248                         goto out;
 249                 image->initrd_buf_len = ret;
 250                 ret = 0;
 251         }
 252
 253         if (cmdline_len) {
 254                 image->cmdline_buf = memdup_user(cmdline_ptr, cmdline_len);
 255                 if (IS_ERR(image->cmdline_buf)) {
 256                         ret = PTR_ERR(image->cmdline_buf);
 257                         image->cmdline_buf = NULL;
 258                         goto out;
 259                 }
 260
 261                 image->cmdline_buf_len = cmdline_len;
 262
 263                 /* command line should be a string with last byte null */
 264                 if (image->cmdline_buf[cmdline_len - 1] != '\0') {
 265                         ret = -EINVAL;
 266                         goto out;
 267                 }
 268
 269                 ima_kexec_cmdline(kernel_fd, image->cmdline_buf,
 270                                   image->cmdline_buf_len - 1);
 271         }
 272
 273         /* IMA needs to pass the measurement list to the next kernel. */
 274         ima_add_kexec_buffer(image);
 275
 276         /* Call arch image load handlers */
 277         ldata = arch_kexec_kernel_image_load(image);
 278
 279         if (IS_ERR(ldata)) {
 280                 ret = PTR_ERR(ldata);
 281                 goto out;
 282         }
 283
 284         image->image_loader_data = ldata;
 285 out:
 286         /* In case of error, free up all allocated memory in this function */
 287         if (ret)
 288                 kimage_file_post_load_cleanup(image);
 289         return ret;
 290 }
 291
 292 static int
 293 kimage_file_alloc_init(struct kimage **rimage, int kernel_fd,
 294                        int initrd_fd, const char __user *cmdline_ptr,
 295                        unsigned long cmdline_len, unsigned long flags)
 296 {
 297         int ret;
 298         struct kimage *image;
 299         bool kexec_on_panic = flags & KEXEC_FILE_ON_CRASH;
 300
 301         image = do_kimage_alloc_init();
 302         if (!image)
 303                 return -ENOMEM;
 304
 305         image->file_mode = 1;
 306
 307         if (kexec_on_panic) {
 308                 /* Enable special crash kernel control page alloc policy. */
 309                 image->control_page = crashk_res.start;
 310                 image->type = KEXEC_TYPE_CRASH;
 311         }
 312
 313         ret = kimage_file_prepare_segments(image, kernel_fd, initrd_fd,
 314                                            cmdline_ptr, cmdline_len, flags);
 315         if (ret)
 316                 goto out_free_image;
 317
 318         ret = sanity_check_segment_list(image);
 319         if (ret)
 320                 goto out_free_post_load_bufs;
 321
 322         ret = -ENOMEM;
 323         image->control_code_page = kimage_alloc_control_pages(image,
 324                                            get_order(KEXEC_CONTROL_PAGE_SIZE));
 325         if (!image->control_code_page) {
 326                 pr_err("Could not allocate control_code_buffer\n");
 327                 goto out_free_post_load_bufs;
 328         }
 329
 330         if (!kexec_on_panic) {
 331                 image->swap_page = kimage_alloc_control_pages(image, 0);
 332                 if (!image->swap_page) {
 333                         pr_err("Could not allocate swap buffer\n");
 334                         goto out_free_control_pages;
 335                 }
 336         }
 337
 338         *rimage = image;
 339         return 0;
 340 out_free_control_pages:
 341         kimage_free_page_list(&image->control_pages);
 342 out_free_post_load_bufs:
 343         kimage_file_post_load_cleanup(image);
 344 out_free_image:
 345         kfree(image);
 346         return ret;
 347 }
 348
 349 SYSCALL_DEFINE5(kexec_file_load, int, kernel_fd, int, initrd_fd,
 350                 unsigned long, cmdline_len, const char __user *, cmdline_ptr,
 351                 unsigned long, flags)
 352 {
 353         int ret = 0, i;
 354         struct kimage **dest_image, *image;
 355
 356         /* We only trust the superuser with rebooting the system. */
 357         if (!capable(CAP_SYS_BOOT) || kexec_load_disabled)
 358                 return -EPERM;
 359
 360         /* Make sure we have a legal set of flags */
 361         if (flags != (flags & KEXEC_FILE_FLAGS))
 362                 return -EINVAL;
 363
 364         image = NULL;
 365
 366         if (!mutex_trylock(&kexec_mutex))
 367                 return -EBUSY;
 368
 369         dest_image = &kexec_image;
 370         if (flags & KEXEC_FILE_ON_CRASH) {
 371                 dest_image = &kexec_crash_image;
 372                 if (kexec_crash_image)
 373                         arch_kexec_unprotect_crashkres();
 374         }
 375
 376         if (flags & KEXEC_FILE_UNLOAD)
 377                 goto exchange;
 378
 379         /*
 380          * In case of crash, new kernel gets loaded in reserved region. It is
 381          * same memory where old crash kernel might be loaded. Free any
 382          * current crash dump kernel before we corrupt it.
 383          */
 384         if (flags & KEXEC_FILE_ON_CRASH)
 385                 kimage_free(xchg(&kexec_crash_image, NULL));
 386
 387         ret = kimage_file_alloc_init(&image, kernel_fd, initrd_fd, cmdline_ptr,
 388                                      cmdline_len, flags);
 389         if (ret)
 390                 goto out;
 391
 392         ret = machine_kexec_prepare(image);
 393         if (ret)
 394                 goto out;
 395
 396         /*
 397          * Some architecture(like S390) may touch the crash memory before
 398          * machine_kexec_prepare(), we must copy vmcoreinfo data after it.
 399          */
 400         ret = kimage_crash_copy_vmcoreinfo(image);
 401         if (ret)
 402                 goto out;
 403
 404         ret = kexec_calculate_store_digests(image);
 405         if (ret)
 406                 goto out;
 407
 408         for (i = 0; i < image->nr_segments; i++) {
 409                 struct kexec_segment *ksegment;
 410
 411                 ksegment = &image->segment[i];
 412                 pr_debug("Loading segment %d: buf=0x%p bufsz=0x%zx mem=0x%lx memsz=0x%zx\n",
 413                          i, ksegment->buf, ksegment->bufsz, ksegment->mem,
 414                          ksegment->memsz);
 415
 416                 ret = kimage_load_segment(image, &image->segment[i]);
 417                 if (ret)
 418                         goto out;
 419         }
 420
 421         kimage_terminate(image);
 422
 423         ret = machine_kexec_post_load(image);
 424         if (ret)
 425                 goto out;
 426
 427         /*
 428          * Free up any temporary buffers allocated which are not needed
 429          * after image has been loaded
 430          */
 431         kimage_file_post_load_cleanup(image);
 432 exchange:
 433         image = xchg(dest_image, image);
 434 out:
 435         if ((flags & KEXEC_FILE_ON_CRASH) && kexec_crash_image)
 436                 arch_kexec_protect_crashkres();
 437
 438         mutex_unlock(&kexec_mutex);
 439         kimage_free(image);
 440         return ret;
 441 }
 442
 443 static int locate_mem_hole_top_down(unsigned long start, unsigned long end,
 444                                     struct kexec_buf *kbuf)
 445 {
 446         struct kimage *image = kbuf->image;
 447         unsigned long temp_start, temp_end;
 448
 449         temp_end = min(end, kbuf->buf_max);
 450         temp_start = temp_end - kbuf->memsz;
 451
 452         do {
 453                 /* align down start */
 454                 temp_start = temp_start & (~(kbuf->buf_align - 1));
 455
 456                 if (temp_start < start || temp_start < kbuf->buf_min)
 457                         return 0;
 458
 459                 temp_end = temp_start + kbuf->memsz - 1;
 460
 461                 /*
 462                  * Make sure this does not conflict with any of existing
 463                  * segments
 464                  */
 465                 if (kimage_is_destination_range(image, temp_start, temp_end)) {
 466                         temp_start = temp_start - PAGE_SIZE;
 467                         continue;
 468                 }
 469
 470                 /* We found a suitable memory range */
 471                 break;
 472         } while (1);
 473
 474         /* If we are here, we found a suitable memory range */
 475         kbuf->mem = temp_start;
 476
 477         /* Success, stop navigating through remaining System RAM ranges */
 478         return 1;
 479 }
 480
 481 static int locate_mem_hole_bottom_up(unsigned long start, unsigned long end,
 482                                      struct kexec_buf *kbuf)
 483 {
 484         struct kimage *image = kbuf->image;
 485         unsigned long temp_start, temp_end;
 486
 487         temp_start = max(start, kbuf->buf_min);
 488
 489         do {
 490                 temp_start = ALIGN(temp_start, kbuf->buf_align);
 491                 temp_end = temp_start + kbuf->memsz - 1;
 492
 493                 if (temp_end > end || temp_end > kbuf->buf_max)
 494                         return 0;
 495                 /*
 496                  * Make sure this does not conflict with any of existing
 497                  * segments
 498                  */
 499                 if (kimage_is_destination_range(image, temp_start, temp_end)) {
 500                         temp_start = temp_start + PAGE_SIZE;
 501                         continue;
 502                 }
 503
 504                 /* We found a suitable memory range */
 505                 break;
 506         } while (1);
 507
 508         /* If we are here, we found a suitable memory range */
 509         kbuf->mem = temp_start;
 510
 511         /* Success, stop navigating through remaining System RAM ranges */
 512         return 1;
 513 }
 514
 515 static int locate_mem_hole_callback(struct resource *res, void *arg)
 516 {
 517         struct kexec_buf *kbuf = (struct kexec_buf *)arg;
 518         u64 start = res->start, end = res->end;
 519         unsigned long sz = end - start + 1;
 520
 521         /* Returning 0 will take to next memory range */
 522
 523         /* Don't use memory that will be detected and handled by a driver. */
 524         if (res->flags & IORESOURCE_SYSRAM_DRIVER_MANAGED)
 525                 return 0;
 526
 527         if (sz < kbuf->memsz)
 528                 return 0;
 529
 530         if (end < kbuf->buf_min || start > kbuf->buf_max)
 531                 return 0;
 532
 533         /*
 534          * Allocate memory top down with-in ram range. Otherwise bottom up
 535          * allocation.
 536          */
 537         if (kbuf->top_down)
 538                 return locate_mem_hole_top_down(start, end, kbuf);
 539         return locate_mem_hole_bottom_up(start, end, kbuf);
 540 }
 541
 542 #ifdef CONFIG_ARCH_KEEP_MEMBLOCK
 543 static int kexec_walk_memblock(struct kexec_buf *kbuf,
 544                                int (*func)(struct resource *, void *))
 545 {
 546         int ret = 0;
 547         u64 i;
 548         phys_addr_t mstart, mend;
 549         struct resource res = { };
 550
 551         if (kbuf->image->type == KEXEC_TYPE_CRASH)
 552                 return func(&crashk_res, kbuf);
 553
 554         if (kbuf->top_down) {
 555                 for_each_free_mem_range_reverse(i, NUMA_NO_NODE, MEMBLOCK_NONE,
 556                                                 &mstart, &mend, NULL) {
 557                         /*
 558                          * In memblock, end points to the first byte after the
 559                          * range while in kexec, end points to the last byte
 560                          * in the range.
 561                          */
 562                         res.start = mstart;
 563                         res.end = mend - 1;
 564                         ret = func(&res, kbuf);
 565                         if (ret)
 566                                 break;
 567                 }
 568         } else {
 569                 for_each_free_mem_range(i, NUMA_NO_NODE, MEMBLOCK_NONE,
 570                                         &mstart, &mend, NULL) {
 571                         /*
 572                          * In memblock, end points to the first byte after the
 573                          * range while in kexec, end points to the last byte
 574                          * in the range.
 575                          */
 576                         res.start = mstart;
 577                         res.end = mend - 1;
 578                         ret = func(&res, kbuf);
 579                         if (ret)
 580                                 break;
 581                 }
 582         }
 583
 584         return ret;
 585 }
 586 #else
 587 static int kexec_walk_memblock(struct kexec_buf *kbuf,
 588                                int (*func)(struct resource *, void *))
 589 {
 590         return 0;
 591 }
 592 #endif
 593
 594 /**
 595  * kexec_walk_resources - call func(data) on free memory regions
 596  * @kbuf:       Context info for the search. Also passed to @func.
 597  * @func:       Function to call for each memory region.
 598  *
 599  * Return: The memory walk will stop when func returns a non-zero value
 600  * and that value will be returned. If all free regions are visited without
 601  * func returning non-zero, then zero will be returned.
 602  */
 603 static int kexec_walk_resources(struct kexec_buf *kbuf,
 604                                 int (*func)(struct resource *, void *))
 605 {
 606         if (kbuf->image->type == KEXEC_TYPE_CRASH)
 607                 return walk_iomem_res_desc(crashk_res.desc,
 608                                            IORESOURCE_SYSTEM_RAM | IORESOURCE_BUSY,
 609                                            crashk_res.start, crashk_res.end,
 610                                            kbuf, func);
 611         else
 612                 return walk_system_ram_res(0, ULONG_MAX, kbuf, func);
 613 }
 614
 615 /**
 616  * kexec_locate_mem_hole - find free memory for the purgatory or the next kernel
 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 kexec_locate_mem_hole(struct kexec_buf *kbuf)
 624 {
 625         int ret;
 626
 627         /* Arch knows where to place */
 628         if (kbuf->mem != KEXEC_BUF_MEM_UNKNOWN)
 629                 return 0;
 630
 631         if (!IS_ENABLED(CONFIG_ARCH_KEEP_MEMBLOCK))
 632                 ret = kexec_walk_resources(kbuf, locate_mem_hole_callback);
 633         else
 634                 ret = kexec_walk_memblock(kbuf, locate_mem_hole_callback);
 635
 636         return ret == 1 ? 0 : -EADDRNOTAVAIL;
 637 }
 638
 639 /**
 640  * arch_kexec_locate_mem_hole - Find free memory to place the segments.
 641  * @kbuf:                       Parameters for the memory search.
 642  *
 643  * On success, kbuf->mem will have the start address of the memory region found.
 644  *
 645  * Return: 0 on success, negative errno on error.
 646  */
 647 int __weak arch_kexec_locate_mem_hole(struct kexec_buf *kbuf)
 648 {
 649         return kexec_locate_mem_hole(kbuf);
 650 }
 651
 652 /**
 653  * kexec_add_buffer - place a buffer in a kexec segment
 654  * @kbuf:       Buffer contents and memory parameters.
 655  *
 656  * This function assumes that kexec_mutex is held.
 657  * On successful return, @kbuf->mem will have the physical address of
 658  * the buffer in memory.
 659  *
 660  * Return: 0 on success, negative errno on error.
 661  */
 662 int kexec_add_buffer(struct kexec_buf *kbuf)
 663 {
 664         struct kexec_segment *ksegment;
 665         int ret;
 666
 667         /* Currently adding segment this way is allowed only in file mode */
 668         if (!kbuf->image->file_mode)
 669                 return -EINVAL;
 670
 671         if (kbuf->image->nr_segments >= KEXEC_SEGMENT_MAX)
 672                 return -EINVAL;
 673
 674         /*
 675          * Make sure we are not trying to add buffer after allocating
 676          * control pages. All segments need to be placed first before
 677          * any control pages are allocated. As control page allocation
 678          * logic goes through list of segments to make sure there are
 679          * no destination overlaps.
 680          */
 681         if (!list_empty(&kbuf->image->control_pages)) {
 682                 WARN_ON(1);
 683                 return -EINVAL;
 684         }
 685
 686         /* Ensure minimum alignment needed for segments. */
 687         kbuf->memsz = ALIGN(kbuf->memsz, PAGE_SIZE);
 688         kbuf->buf_align = max(kbuf->buf_align, PAGE_SIZE);
 689
 690         /* Walk the RAM ranges and allocate a suitable range for the buffer */
 691         ret = arch_kexec_locate_mem_hole(kbuf);
 692         if (ret)
 693                 return ret;
 694
 695         /* Found a suitable memory range */
 696         ksegment = &kbuf->image->segment[kbuf->image->nr_segments];
 697         ksegment->kbuf = kbuf->buffer;
 698         ksegment->bufsz = kbuf->bufsz;
 699         ksegment->mem = kbuf->mem;
 700         ksegment->memsz = kbuf->memsz;
 701         kbuf->image->nr_segments++;
 702         return 0;
 703 }
 704
 705 /* Calculate and store the digest of segments */
 706 static int kexec_calculate_store_digests(struct kimage *image)
 707 {
 708         struct crypto_shash *tfm;
 709         struct shash_desc *desc;
 710         int ret = 0, i, j, zero_buf_sz, sha_region_sz;
 711         size_t desc_size, nullsz;
 712         char *digest;
 713         void *zero_buf;
 714         struct kexec_sha_region *sha_regions;
 715         struct purgatory_info *pi = &image->purgatory_info;
 716
 717         if (!IS_ENABLED(CONFIG_ARCH_HAS_KEXEC_PURGATORY))
 718                 return 0;
 719
 720         zero_buf = __va(page_to_pfn(ZERO_PAGE(0)) << PAGE_SHIFT);
 721         zero_buf_sz = PAGE_SIZE;
 722
 723         tfm = crypto_alloc_shash("sha256", 0, 0);
 724         if (IS_ERR(tfm)) {
 725                 ret = PTR_ERR(tfm);
 726                 goto out;
 727         }
 728
 729         desc_size = crypto_shash_descsize(tfm) + sizeof(*desc);
 730         desc = kzalloc(desc_size, GFP_KERNEL);
 731         if (!desc) {
 732                 ret = -ENOMEM;
 733                 goto out_free_tfm;
 734         }
 735
 736         sha_region_sz = KEXEC_SEGMENT_MAX * sizeof(struct kexec_sha_region);
 737         sha_regions = vzalloc(sha_region_sz);
 738         if (!sha_regions)
 739                 goto out_free_desc;
 740
 741         desc->tfm   = tfm;
 742
 743         ret = crypto_shash_init(desc);
 744         if (ret < 0)
 745                 goto out_free_sha_regions;
 746
 747         digest = kzalloc(SHA256_DIGEST_SIZE, GFP_KERNEL);
 748         if (!digest) {
 749                 ret = -ENOMEM;
 750                 goto out_free_sha_regions;
 751         }
 752
 753         for (j = i = 0; i < image->nr_segments; i++) {
 754                 struct kexec_segment *ksegment;
 755
 756                 ksegment = &image->segment[i];
 757                 /*
 758                  * Skip purgatory as it will be modified once we put digest
 759                  * info in purgatory.
 760                  */
 761                 if (ksegment->kbuf == pi->purgatory_buf)
 762                         continue;
 763
 764                 ret = crypto_shash_update(desc, ksegment->kbuf,
 765                                           ksegment->bufsz);
 766                 if (ret)
 767                         break;
 768
 769                 /*
 770                  * Assume rest of the buffer is filled with zero and
 771                  * update digest accordingly.
 772                  */
 773                 nullsz = ksegment->memsz - ksegment->bufsz;
 774                 while (nullsz) {
 775                         unsigned long bytes = nullsz;
 776
 777                         if (bytes > zero_buf_sz)
 778                                 bytes = zero_buf_sz;
 779                         ret = crypto_shash_update(desc, zero_buf, bytes);
 780                         if (ret)
 781                                 break;
 782                         nullsz -= bytes;
 783                 }
 784
 785                 if (ret)
 786                         break;
 787
 788                 sha_regions[j].start = ksegment->mem;
 789                 sha_regions[j].len = ksegment->memsz;
 790                 j++;
 791         }
 792
 793         if (!ret) {
 794                 ret = crypto_shash_final(desc, digest);
 795                 if (ret)
 796                         goto out_free_digest;
 797                 ret = kexec_purgatory_get_set_symbol(image, "purgatory_sha_regions",
 798                                                      sha_regions, sha_region_sz, 0);
 799                 if (ret)
 800                         goto out_free_digest;
 801
 802                 ret = kexec_purgatory_get_set_symbol(image, "purgatory_sha256_digest",
 803                                                      digest, SHA256_DIGEST_SIZE, 0);
 804                 if (ret)
 805                         goto out_free_digest;
 806         }
 807
 808 out_free_digest:
 809         kfree(digest);
 810 out_free_sha_regions:
 811         vfree(sha_regions);
 812 out_free_desc:
 813         kfree(desc);
 814 out_free_tfm:
 815         kfree(tfm);
 816 out:
 817         return ret;
 818 }
 819
 820 #ifdef CONFIG_ARCH_HAS_KEXEC_PURGATORY
 821 /*
 822  * kexec_purgatory_setup_kbuf - prepare buffer to load purgatory.
 823  * @pi:         Purgatory to be loaded.
 824  * @kbuf:       Buffer to setup.
 825  *
 826  * Allocates the memory needed for the buffer. Caller is responsible to free
 827  * the memory after use.
 828  *
 829  * Return: 0 on success, negative errno on error.
 830  */
 831 static int kexec_purgatory_setup_kbuf(struct purgatory_info *pi,
 832                                       struct kexec_buf *kbuf)
 833 {
 834         const Elf_Shdr *sechdrs;
 835         unsigned long bss_align;
 836         unsigned long bss_sz;
 837         unsigned long align;
 838         int i, ret;
 839
 840         sechdrs = (void *)pi->ehdr + pi->ehdr->e_shoff;
 841         kbuf->buf_align = bss_align = 1;
 842         kbuf->bufsz = bss_sz = 0;
 843
 844         for (i = 0; i < pi->ehdr->e_shnum; i++) {
 845                 if (!(sechdrs[i].sh_flags & SHF_ALLOC))
 846                         continue;
 847
 848                 align = sechdrs[i].sh_addralign;
 849                 if (sechdrs[i].sh_type != SHT_NOBITS) {
 850                         if (kbuf->buf_align < align)
 851                                 kbuf->buf_align = align;
 852                         kbuf->bufsz = ALIGN(kbuf->bufsz, align);
 853                         kbuf->bufsz += sechdrs[i].sh_size;
 854                 } else {
 855                         if (bss_align < align)
 856                                 bss_align = align;
 857                         bss_sz = ALIGN(bss_sz, align);
 858                         bss_sz += sechdrs[i].sh_size;
 859                 }
 860         }
 861         kbuf->bufsz = ALIGN(kbuf->bufsz, bss_align);
 862         kbuf->memsz = kbuf->bufsz + bss_sz;
 863         if (kbuf->buf_align < bss_align)
 864                 kbuf->buf_align = bss_align;
 865
 866         kbuf->buffer = vzalloc(kbuf->bufsz);
 867         if (!kbuf->buffer)
 868                 return -ENOMEM;
 869         pi->purgatory_buf = kbuf->buffer;
 870
 871         ret = kexec_add_buffer(kbuf);
 872         if (ret)
 873                 goto out;
 874
 875         return 0;
 876 out:
 877         vfree(pi->purgatory_buf);
 878         pi->purgatory_buf = NULL;
 879         return ret;
 880 }
 881
 882 /*
 883  * kexec_purgatory_setup_sechdrs - prepares the pi->sechdrs buffer.
 884  * @pi:         Purgatory to be loaded.
 885  * @kbuf:       Buffer prepared to store purgatory.
 886  *
 887  * Allocates the memory needed for the buffer. Caller is responsible to free
 888  * the memory after use.
 889  *
 890  * Return: 0 on success, negative errno on error.
 891  */
 892 static int kexec_purgatory_setup_sechdrs(struct purgatory_info *pi,
 893                                          struct kexec_buf *kbuf)
 894 {
 895         unsigned long bss_addr;
 896         unsigned long offset;
 897         Elf_Shdr *sechdrs;
 898         int i;
 899
 900         /*
 901          * The section headers in kexec_purgatory are read-only. In order to
 902          * have them modifiable make a temporary copy.
 903          */
 904         sechdrs = vzalloc(array_size(sizeof(Elf_Shdr), pi->ehdr->e_shnum));
 905         if (!sechdrs)
 906                 return -ENOMEM;
 907         memcpy(sechdrs, (void *)pi->ehdr + pi->ehdr->e_shoff,
 908                pi->ehdr->e_shnum * sizeof(Elf_Shdr));
 909         pi->sechdrs = sechdrs;
 910
 911         offset = 0;
 912         bss_addr = kbuf->mem + kbuf->bufsz;
 913         kbuf->image->start = pi->ehdr->e_entry;
 914
 915         for (i = 0; i < pi->ehdr->e_shnum; i++) {
 916                 unsigned long align;
 917                 void *src, *dst;
 918
 919                 if (!(sechdrs[i].sh_flags & SHF_ALLOC))
 920                         continue;
 921
 922                 align = sechdrs[i].sh_addralign;
 923                 if (sechdrs[i].sh_type == SHT_NOBITS) {
 924                         bss_addr = ALIGN(bss_addr, align);
 925                         sechdrs[i].sh_addr = bss_addr;
 926                         bss_addr += sechdrs[i].sh_size;
 927                         continue;
 928                 }
 929
 930                 offset = ALIGN(offset, align);
 931                 if (sechdrs[i].sh_flags & SHF_EXECINSTR &&
 932                     pi->ehdr->e_entry >= sechdrs[i].sh_addr &&
 933                     pi->ehdr->e_entry < (sechdrs[i].sh_addr
 934                                          + sechdrs[i].sh_size)) {
 935                         kbuf->image->start -= sechdrs[i].sh_addr;
 936                         kbuf->image->start += kbuf->mem + offset;
 937                 }
 938
 939                 src = (void *)pi->ehdr + sechdrs[i].sh_offset;
 940                 dst = pi->purgatory_buf + offset;
 941                 memcpy(dst, src, sechdrs[i].sh_size);
 942
 943                 sechdrs[i].sh_addr = kbuf->mem + offset;
 944                 sechdrs[i].sh_offset = offset;
 945                 offset += sechdrs[i].sh_size;
 946         }
 947
 948         return 0;
 949 }
 950
 951 static int kexec_apply_relocations(struct kimage *image)
 952 {
 953         int i, ret;
 954         struct purgatory_info *pi = &image->purgatory_info;
 955         const Elf_Shdr *sechdrs;
 956
 957         sechdrs = (void *)pi->ehdr + pi->ehdr->e_shoff;
 958
 959         for (i = 0; i < pi->ehdr->e_shnum; i++) {
 960                 const Elf_Shdr *relsec;
 961                 const Elf_Shdr *symtab;
 962                 Elf_Shdr *section;
 963
 964                 relsec = sechdrs + i;
 965
 966                 if (relsec->sh_type != SHT_RELA &&
 967                     relsec->sh_type != SHT_REL)
 968                         continue;
 969
 970                 /*
 971                  * For section of type SHT_RELA/SHT_REL,
 972                  * ->sh_link contains section header index of associated
 973                  * symbol table. And ->sh_info contains section header
 974                  * index of section to which relocations apply.
 975                  */
 976                 if (relsec->sh_info >= pi->ehdr->e_shnum ||
 977                     relsec->sh_link >= pi->ehdr->e_shnum)
 978                         return -ENOEXEC;
 979
 980                 section = pi->sechdrs + relsec->sh_info;
 981                 symtab = sechdrs + relsec->sh_link;
 982
 983                 if (!(section->sh_flags & SHF_ALLOC))
 984                         continue;
 985
 986                 /*
 987                  * symtab->sh_link contain section header index of associated
 988                  * string table.
 989                  */
 990                 if (symtab->sh_link >= pi->ehdr->e_shnum)
 991                         /* Invalid section number? */
 992                         continue;
 993
 994                 /*
 995                  * Respective architecture needs to provide support for applying
 996                  * relocations of type SHT_RELA/SHT_REL.
 997                  */
 998                 if (relsec->sh_type == SHT_RELA)
 999                         ret = arch_kexec_apply_relocations_add(pi, section,
1000                                                                relsec, symtab);
1001                 else if (relsec->sh_type == SHT_REL)
1002                         ret = arch_kexec_apply_relocations(pi, section,
1003                                                            relsec, symtab);
1004                 if (ret)
1005                         return ret;
1006         }
1007
1008         return 0;
1009 }
1010
1011 /*
1012  * kexec_load_purgatory - Load and relocate the purgatory object.
1013  * @image:      Image to add the purgatory to.
1014  * @kbuf:       Memory parameters to use.
1015  *
1016  * Allocates the memory needed for image->purgatory_info.sechdrs and
1017  * image->purgatory_info.purgatory_buf/kbuf->buffer. Caller is responsible
1018  * to free the memory after use.
1019  *
1020  * Return: 0 on success, negative errno on error.
1021  */
1022 int kexec_load_purgatory(struct kimage *image, struct kexec_buf *kbuf)
1023 {
1024         struct purgatory_info *pi = &image->purgatory_info;
1025         int ret;
1026
1027         if (kexec_purgatory_size <= 0)
1028                 return -EINVAL;
1029
1030         pi->ehdr = (const Elf_Ehdr *)kexec_purgatory;
1031
1032         ret = kexec_purgatory_setup_kbuf(pi, kbuf);
1033         if (ret)
1034                 return ret;
1035
1036         ret = kexec_purgatory_setup_sechdrs(pi, kbuf);
1037         if (ret)
1038                 goto out_free_kbuf;
1039
1040         ret = kexec_apply_relocations(image);
1041         if (ret)
1042                 goto out;
1043
1044         return 0;
1045 out:
1046         vfree(pi->sechdrs);
1047         pi->sechdrs = NULL;
1048 out_free_kbuf:
1049         vfree(pi->purgatory_buf);
1050         pi->purgatory_buf = NULL;
1051         return ret;
1052 }
1053
1054 /*
1055  * kexec_purgatory_find_symbol - find a symbol in the purgatory
1056  * @pi:         Purgatory to search in.
1057  * @name:       Name of the symbol.
1058  *
1059  * Return: pointer to symbol in read-only symtab on success, NULL on error.
1060  */
1061 static const Elf_Sym *kexec_purgatory_find_symbol(struct purgatory_info *pi,
1062                                                   const char *name)
1063 {
1064         const Elf_Shdr *sechdrs;
1065         const Elf_Ehdr *ehdr;
1066         const Elf_Sym *syms;
1067         const char *strtab;
1068         int i, k;
1069
1070         if (!pi->ehdr)
1071                 return NULL;
1072
1073         ehdr = pi->ehdr;
1074         sechdrs = (void *)ehdr + ehdr->e_shoff;
1075
1076         for (i = 0; i < ehdr->e_shnum; i++) {
1077                 if (sechdrs[i].sh_type != SHT_SYMTAB)
1078                         continue;
1079
1080                 if (sechdrs[i].sh_link >= ehdr->e_shnum)
1081                         /* Invalid strtab section number */
1082                         continue;
1083                 strtab = (void *)ehdr + sechdrs[sechdrs[i].sh_link].sh_offset;
1084                 syms = (void *)ehdr + sechdrs[i].sh_offset;
1085
1086                 /* Go through symbols for a match */
1087                 for (k = 0; k < sechdrs[i].sh_size/sizeof(Elf_Sym); k++) {
1088                         if (ELF_ST_BIND(syms[k].st_info) != STB_GLOBAL)
1089                                 continue;
1090
1091                         if (strcmp(strtab + syms[k].st_name, name) != 0)
1092                                 continue;
1093
1094                         if (syms[k].st_shndx == SHN_UNDEF ||
1095                             syms[k].st_shndx >= ehdr->e_shnum) {
1096                                 pr_debug("Symbol: %s has bad section index %d.\n",
1097                                                 name, syms[k].st_shndx);
1098                                 return NULL;
1099                         }
1100
1101                         /* Found the symbol we are looking for */
1102                         return &syms[k];
1103                 }
1104         }
1105
1106         return NULL;
1107 }
1108
1109 void *kexec_purgatory_get_symbol_addr(struct kimage *image, const char *name)
1110 {
1111         struct purgatory_info *pi = &image->purgatory_info;
1112         const Elf_Sym *sym;
1113         Elf_Shdr *sechdr;
1114
1115         sym = kexec_purgatory_find_symbol(pi, name);
1116         if (!sym)
1117                 return ERR_PTR(-EINVAL);
1118
1119         sechdr = &pi->sechdrs[sym->st_shndx];
1120
1121         /*
1122          * Returns the address where symbol will finally be loaded after
1123          * kexec_load_segment()
1124          */
1125         return (void *)(sechdr->sh_addr + sym->st_value);
1126 }
1127
1128 /*
1129  * Get or set value of a symbol. If "get_value" is true, symbol value is
1130  * returned in buf otherwise symbol value is set based on value in buf.
1131  */
1132 int kexec_purgatory_get_set_symbol(struct kimage *image, const char *name,
1133                                    void *buf, unsigned int size, bool get_value)
1134 {
1135         struct purgatory_info *pi = &image->purgatory_info;
1136         const Elf_Sym *sym;
1137         Elf_Shdr *sec;
1138         char *sym_buf;
1139
1140         sym = kexec_purgatory_find_symbol(pi, name);
1141         if (!sym)
1142                 return -EINVAL;
1143
1144         if (sym->st_size != size) {
1145                 pr_err("symbol %s size mismatch: expected %lu actual %u\n",
1146                        name, (unsigned long)sym->st_size, size);
1147                 return -EINVAL;
1148         }
1149
1150         sec = pi->sechdrs + sym->st_shndx;
1151
1152         if (sec->sh_type == SHT_NOBITS) {
1153                 pr_err("symbol %s is in a bss section. Cannot %s\n", name,
1154                        get_value ? "get" : "set");
1155                 return -EINVAL;
1156         }
1157
1158         sym_buf = (char *)pi->purgatory_buf + sec->sh_offset + sym->st_value;
1159
1160         if (get_value)
1161                 memcpy((void *)buf, sym_buf, size);
1162         else
1163                 memcpy((void *)sym_buf, buf, size);
1164
1165         return 0;
1166 }
1167 #endif /* CONFIG_ARCH_HAS_KEXEC_PURGATORY */
1168
1169 int crash_exclude_mem_range(struct crash_mem *mem,
1170                             unsigned long long mstart, unsigned long long mend)
1171 {
1172         int i, j;
1173         unsigned long long start, end, p_start, p_end;
1174         struct crash_mem_range temp_range = {0, 0};
1175
1176         for (i = 0; i < mem->nr_ranges; i++) {
1177                 start = mem->ranges[i].start;
1178                 end = mem->ranges[i].end;
1179                 p_start = mstart;
1180                 p_end = mend;
1181
1182                 if (mstart > end || mend < start)
1183                         continue;
1184
1185                 /* Truncate any area outside of range */
1186                 if (mstart < start)
1187                         p_start = start;
1188                 if (mend > end)
1189                         p_end = end;
1190
1191                 /* Found completely overlapping range */
1192                 if (p_start == start && p_end == end) {
1193                         mem->ranges[i].start = 0;
1194                         mem->ranges[i].end = 0;
1195                         if (i < mem->nr_ranges - 1) {
1196                                 /* Shift rest of the ranges to left */
1197                                 for (j = i; j < mem->nr_ranges - 1; j++) {
1198                                         mem->ranges[j].start =
1199                                                 mem->ranges[j+1].start;
1200                                         mem->ranges[j].end =
1201                                                         mem->ranges[j+1].end;
1202                                 }
1203
1204                                 /*
1205                                  * Continue to check if there are another overlapping ranges
1206                                  * from the current position because of shifting the above
1207                                  * mem ranges.
1208                                  */
1209                                 i--;
1210                                 mem->nr_ranges--;
1211                                 continue;
1212                         }
1213                         mem->nr_ranges--;
1214                         return 0;
1215                 }
1216
1217                 if (p_start > start && p_end < end) {
1218                         /* Split original range */
1219                         mem->ranges[i].end = p_start - 1;
1220                         temp_range.start = p_end + 1;
1221                         temp_range.end = end;
1222                 } else if (p_start != start)
1223                         mem->ranges[i].end = p_start - 1;
1224                 else
1225                         mem->ranges[i].start = p_end + 1;
1226                 break;
1227         }
1228
1229         /* If a split happened, add the split to array */
1230         if (!temp_range.end)
1231                 return 0;
1232
1233         /* Split happened */
1234         if (i == mem->max_nr_ranges - 1)
1235                 return -ENOMEM;
1236
1237         /* Location where new range should go */
1238         j = i + 1;
1239         if (j < mem->nr_ranges) {
1240                 /* Move over all ranges one slot towards the end */
1241                 for (i = mem->nr_ranges - 1; i >= j; i--)
1242                         mem->ranges[i + 1] = mem->ranges[i];
1243         }
1244
1245         mem->ranges[j].start = temp_range.start;
1246         mem->ranges[j].end = temp_range.end;
1247         mem->nr_ranges++;
1248         return 0;
1249 }
1250
1251 int crash_prepare_elf64_headers(struct crash_mem *mem, int kernel_map,
1252                           void **addr, unsigned long *sz)
1253 {
1254         Elf64_Ehdr *ehdr;
1255         Elf64_Phdr *phdr;
1256         unsigned long nr_cpus = num_possible_cpus(), nr_phdr, elf_sz;
1257         unsigned char *buf;
1258         unsigned int cpu, i;
1259         unsigned long long notes_addr;
1260         unsigned long mstart, mend;
1261
1262         /* extra phdr for vmcoreinfo ELF note */
1263         nr_phdr = nr_cpus + 1;
1264         nr_phdr += mem->nr_ranges;
1265
1266         /*
1267          * kexec-tools creates an extra PT_LOAD phdr for kernel text mapping
1268          * area (for example, ffffffff80000000 - ffffffffa0000000 on x86_64).
1269          * I think this is required by tools like gdb. So same physical
1270          * memory will be mapped in two ELF headers. One will contain kernel
1271          * text virtual addresses and other will have __va(physical) addresses.
1272          */
1273
1274         nr_phdr++;
1275         elf_sz = sizeof(Elf64_Ehdr) + nr_phdr * sizeof(Elf64_Phdr);
1276         elf_sz = ALIGN(elf_sz, ELF_CORE_HEADER_ALIGN);
1277
1278         buf = vzalloc(elf_sz);
1279         if (!buf)
1280                 return -ENOMEM;
1281
1282         ehdr = (Elf64_Ehdr *)buf;
1283         phdr = (Elf64_Phdr *)(ehdr + 1);
1284         memcpy(ehdr->e_ident, ELFMAG, SELFMAG);
1285         ehdr->e_ident[EI_CLASS] = ELFCLASS64;
1286         ehdr->e_ident[EI_DATA] = ELFDATA2LSB;
1287         ehdr->e_ident[EI_VERSION] = EV_CURRENT;
1288         ehdr->e_ident[EI_OSABI] = ELF_OSABI;
1289         memset(ehdr->e_ident + EI_PAD, 0, EI_NIDENT - EI_PAD);
1290         ehdr->e_type = ET_CORE;
1291         ehdr->e_machine = ELF_ARCH;
1292         ehdr->e_version = EV_CURRENT;
1293         ehdr->e_phoff = sizeof(Elf64_Ehdr);
1294         ehdr->e_ehsize = sizeof(Elf64_Ehdr);
1295         ehdr->e_phentsize = sizeof(Elf64_Phdr);
1296
1297         /* Prepare one phdr of type PT_NOTE for each present CPU */
1298         for_each_present_cpu(cpu) {
1299                 phdr->p_type = PT_NOTE;
1300                 notes_addr = per_cpu_ptr_to_phys(per_cpu_ptr(crash_notes, cpu));
1301                 phdr->p_offset = phdr->p_paddr = notes_addr;
1302                 phdr->p_filesz = phdr->p_memsz = sizeof(note_buf_t);
1303                 (ehdr->e_phnum)++;
1304                 phdr++;
1305         }
1306
1307         /* Prepare one PT_NOTE header for vmcoreinfo */
1308         phdr->p_type = PT_NOTE;
1309         phdr->p_offset = phdr->p_paddr = paddr_vmcoreinfo_note();
1310         phdr->p_filesz = phdr->p_memsz = VMCOREINFO_NOTE_SIZE;
1311         (ehdr->e_phnum)++;
1312         phdr++;
1313
1314         /* Prepare PT_LOAD type program header for kernel text region */
1315         if (kernel_map) {
1316                 phdr->p_type = PT_LOAD;
1317                 phdr->p_flags = PF_R|PF_W|PF_X;
1318                 phdr->p_vaddr = (unsigned long) _text;
1319                 phdr->p_filesz = phdr->p_memsz = _end - _text;
1320                 phdr->p_offset = phdr->p_paddr = __pa_symbol(_text);
1321                 ehdr->e_phnum++;
1322                 phdr++;
1323         }
1324
1325         /* Go through all the ranges in mem->ranges[] and prepare phdr */
1326         for (i = 0; i < mem->nr_ranges; i++) {
1327                 mstart = mem->ranges[i].start;
1328                 mend = mem->ranges[i].end;
1329
1330                 phdr->p_type = PT_LOAD;
1331                 phdr->p_flags = PF_R|PF_W|PF_X;
1332                 phdr->p_offset  = mstart;
1333
1334                 phdr->p_paddr = mstart;
1335                 phdr->p_vaddr = (unsigned long) __va(mstart);
1336                 phdr->p_filesz = phdr->p_memsz = mend - mstart + 1;
1337                 phdr->p_align = 0;
1338                 ehdr->e_phnum++;
1339                 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",
1340                         phdr, phdr->p_vaddr, phdr->p_paddr, phdr->p_filesz,
1341                         ehdr->e_phnum, phdr->p_offset);
1342                 phdr++;
1343         }
1344
1345         *addr = buf;
1346         *sz = elf_sz;
1347         return 0;
1348 }