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 #ifdef CONFIG_KEXEC_SIG
  33 static bool sig_enforce = IS_ENABLED(CONFIG_KEXEC_SIG_FORCE);
  34
  35 void set_kexec_sig_enforced(void)
  36 {
  37         sig_enforce = true;
  38 }
  39 #endif
  40
  41 static int kexec_calculate_store_digests(struct kimage *image);
  42
  43 /* Maximum size in bytes for kernel/initrd files. */
  44 #define KEXEC_FILE_SIZE_MAX     min_t(s64, 4LL << 30, SSIZE_MAX)
  45
  46 /*
  47  * Currently this is the only default function that is exported as some
  48  * architectures need it to do additional handlings.
  49  * In the future, other default functions may be exported too if required.
  50  */
  51 int kexec_image_probe_default(struct kimage *image, void *buf,
  52                               unsigned long buf_len)
  53 {
  54         const struct kexec_file_ops * const *fops;
  55         int ret = -ENOEXEC;
  56
  57         for (fops = &kexec_file_loaders[0]; *fops && (*fops)->probe; ++fops) {
  58                 ret = (*fops)->probe(buf, buf_len);
  59                 if (!ret) {
  60                         image->fops = *fops;
  61                         return ret;
  62                 }
  63         }
  64
  65         return ret;
  66 }
  67
  68 void *kexec_image_load_default(struct kimage *image)
  69 {
  70         if (!image->fops || !image->fops->load)
  71                 return ERR_PTR(-ENOEXEC);
  72
  73         return image->fops->load(image, image->kernel_buf,
  74                                  image->kernel_buf_len, image->initrd_buf,
  75                                  image->initrd_buf_len, image->cmdline_buf,
  76                                  image->cmdline_buf_len);
  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 /*
  88  * Free up memory used by kernel, initrd, and command line. This is temporary
  89  * memory allocation which is not needed any more after these buffers have
  90  * been loaded into separate segments and have been copied elsewhere.
  91  */
  92 void kimage_file_post_load_cleanup(struct kimage *image)
  93 {
  94         struct purgatory_info *pi = &image->purgatory_info;
  95
  96         vfree(image->kernel_buf);
  97         image->kernel_buf = NULL;
  98
  99         vfree(image->initrd_buf);
 100         image->initrd_buf = NULL;
 101
 102         kfree(image->cmdline_buf);
 103         image->cmdline_buf = NULL;
 104
 105         vfree(pi->purgatory_buf);
 106         pi->purgatory_buf = NULL;
 107
 108         vfree(pi->sechdrs);
 109         pi->sechdrs = NULL;
 110
 111 #ifdef CONFIG_IMA_KEXEC
 112         vfree(image->ima_buffer);
 113         image->ima_buffer = NULL;
 114 #endif /* CONFIG_IMA_KEXEC */
 115
 116         /* See if architecture has anything to cleanup post load */
 117         arch_kimage_file_post_load_cleanup(image);
 118
 119         /*
 120          * Above call should have called into bootloader to free up
 121          * any data stored in kimage->image_loader_data. It should
 122          * be ok now to free it up.
 123          */
 124         kfree(image->image_loader_data);
 125         image->image_loader_data = NULL;
 126 }
 127
 128 #ifdef CONFIG_KEXEC_SIG
 129 #ifdef CONFIG_SIGNED_PE_FILE_VERIFICATION
 130 int kexec_kernel_verify_pe_sig(const char *kernel, unsigned long kernel_len)
 131 {
 132         int ret;
 133
 134         ret = verify_pefile_signature(kernel, kernel_len,
 135                                       VERIFY_USE_SECONDARY_KEYRING,
 136                                       VERIFYING_KEXEC_PE_SIGNATURE);
 137         if (ret == -ENOKEY && IS_ENABLED(CONFIG_INTEGRITY_PLATFORM_KEYRING)) {
 138                 ret = verify_pefile_signature(kernel, kernel_len,
 139                                               VERIFY_USE_PLATFORM_KEYRING,
 140                                               VERIFYING_KEXEC_PE_SIGNATURE);
 141         }
 142         return ret;
 143 }
 144 #endif
 145
 146 static int kexec_image_verify_sig(struct kimage *image, void *buf,
 147                                   unsigned long buf_len)
 148 {
 149         if (!image->fops || !image->fops->verify_sig) {
 150                 pr_debug("kernel loader does not support signature verification.\n");
 151                 return -EKEYREJECTED;
 152         }
 153
 154         return image->fops->verify_sig(buf, buf_len);
 155 }
 156
 157 static int
 158 kimage_validate_signature(struct kimage *image)
 159 {
 160         int ret;
 161
 162         ret = kexec_image_verify_sig(image, image->kernel_buf,
 163                                      image->kernel_buf_len);
 164         if (ret) {
 165
 166                 if (sig_enforce) {
 167                         pr_notice("Enforced kernel signature verification failed (%d).\n", ret);
 168                         return ret;
 169                 }
 170
 171                 /*
 172                  * If IMA is guaranteed to appraise a signature on the kexec
 173                  * image, permit it even if the kernel is otherwise locked
 174                  * down.
 175                  */
 176                 if (!ima_appraise_signature(READING_KEXEC_IMAGE) &&
 177                     security_locked_down(LOCKDOWN_KEXEC))
 178                         return -EPERM;
 179
 180                 pr_debug("kernel signature verification failed (%d).\n", ret);
 181         }
 182
 183         return 0;
 184 }
 185 #endif
 186
 187 /*
 188  * In file mode list of segments is prepared by kernel. Copy relevant
 189  * data from user space, do error checking, prepare segment list
 190  */
 191 static int
 192 kimage_file_prepare_segments(struct kimage *image, int kernel_fd, int initrd_fd,
 193                              const char __user *cmdline_ptr,
 194                              unsigned long cmdline_len, unsigned flags)
 195 {
 196         ssize_t ret;
 197         void *ldata;
 198
 199         ret = kernel_read_file_from_fd(kernel_fd, 0, &image->kernel_buf,
 200                                        KEXEC_FILE_SIZE_MAX, NULL,
 201                                        READING_KEXEC_IMAGE);
 202         if (ret < 0)
 203                 return ret;
 204         image->kernel_buf_len = ret;
 205
 206         /* Call arch image probe handlers */
 207         ret = arch_kexec_kernel_image_probe(image, image->kernel_buf,
 208                                             image->kernel_buf_len);
 209         if (ret)
 210                 goto out;
 211
 212 #ifdef CONFIG_KEXEC_SIG
 213         ret = kimage_validate_signature(image);
 214
 215         if (ret)
 216                 goto out;
 217 #endif
 218         /* It is possible that there no initramfs is being loaded */
 219         if (!(flags & KEXEC_FILE_NO_INITRAMFS)) {
 220                 ret = kernel_read_file_from_fd(initrd_fd, 0, &image->initrd_buf,
 221                                                KEXEC_FILE_SIZE_MAX, NULL,
 222                                                READING_KEXEC_INITRAMFS);
 223                 if (ret < 0)
 224                         goto out;
 225                 image->initrd_buf_len = ret;
 226                 ret = 0;
 227         }
 228
 229         if (cmdline_len) {
 230                 image->cmdline_buf = memdup_user(cmdline_ptr, cmdline_len);
 231                 if (IS_ERR(image->cmdline_buf)) {
 232                         ret = PTR_ERR(image->cmdline_buf);
 233                         image->cmdline_buf = NULL;
 234                         goto out;
 235                 }
 236
 237                 image->cmdline_buf_len = cmdline_len;
 238
 239                 /* command line should be a string with last byte null */
 240                 if (image->cmdline_buf[cmdline_len - 1] != '\0') {
 241                         ret = -EINVAL;
 242                         goto out;
 243                 }
 244
 245                 ima_kexec_cmdline(kernel_fd, image->cmdline_buf,
 246                                   image->cmdline_buf_len - 1);
 247         }
 248
 249         /* IMA needs to pass the measurement list to the next kernel. */
 250         ima_add_kexec_buffer(image);
 251
 252         /* Call arch image load handlers */
 253         ldata = arch_kexec_kernel_image_load(image);
 254
 255         if (IS_ERR(ldata)) {
 256                 ret = PTR_ERR(ldata);
 257                 goto out;
 258         }
 259
 260         image->image_loader_data = ldata;
 261 out:
 262         /* In case of error, free up all allocated memory in this function */
 263         if (ret)
 264                 kimage_file_post_load_cleanup(image);
 265         return ret;
 266 }
 267
 268 static int
 269 kimage_file_alloc_init(struct kimage **rimage, int kernel_fd,
 270                        int initrd_fd, const char __user *cmdline_ptr,
 271                        unsigned long cmdline_len, unsigned long flags)
 272 {
 273         int ret;
 274         struct kimage *image;
 275         bool kexec_on_panic = flags & KEXEC_FILE_ON_CRASH;
 276
 277         image = do_kimage_alloc_init();
 278         if (!image)
 279                 return -ENOMEM;
 280
 281         image->file_mode = 1;
 282
 283         if (kexec_on_panic) {
 284                 /* Enable special crash kernel control page alloc policy. */
 285                 image->control_page = crashk_res.start;
 286                 image->type = KEXEC_TYPE_CRASH;
 287         }
 288
 289         ret = kimage_file_prepare_segments(image, kernel_fd, initrd_fd,
 290                                            cmdline_ptr, cmdline_len, flags);
 291         if (ret)
 292                 goto out_free_image;
 293
 294         ret = sanity_check_segment_list(image);
 295         if (ret)
 296                 goto out_free_post_load_bufs;
 297
 298         ret = -ENOMEM;
 299         image->control_code_page = kimage_alloc_control_pages(image,
 300                                            get_order(KEXEC_CONTROL_PAGE_SIZE));
 301         if (!image->control_code_page) {
 302                 pr_err("Could not allocate control_code_buffer\n");
 303                 goto out_free_post_load_bufs;
 304         }
 305
 306         if (!kexec_on_panic) {
 307                 image->swap_page = kimage_alloc_control_pages(image, 0);
 308                 if (!image->swap_page) {
 309                         pr_err("Could not allocate swap buffer\n");
 310                         goto out_free_control_pages;
 311                 }
 312         }
 313
 314         *rimage = image;
 315         return 0;
 316 out_free_control_pages:
 317         kimage_free_page_list(&image->control_pages);
 318 out_free_post_load_bufs:
 319         kimage_file_post_load_cleanup(image);
 320 out_free_image:
 321         kfree(image);
 322         return ret;
 323 }
 324
 325 SYSCALL_DEFINE5(kexec_file_load, int, kernel_fd, int, initrd_fd,
 326                 unsigned long, cmdline_len, const char __user *, cmdline_ptr,
 327                 unsigned long, flags)
 328 {
 329         int ret = 0, i;
 330         struct kimage **dest_image, *image;
 331
 332         /* We only trust the superuser with rebooting the system. */
 333         if (!capable(CAP_SYS_BOOT) || kexec_load_disabled)
 334                 return -EPERM;
 335
 336         /* Make sure we have a legal set of flags */
 337         if (flags != (flags & KEXEC_FILE_FLAGS))
 338                 return -EINVAL;
 339
 340         image = NULL;
 341
 342         if (!kexec_trylock())
 343                 return -EBUSY;
 344
 345         dest_image = &kexec_image;
 346         if (flags & KEXEC_FILE_ON_CRASH) {
 347                 dest_image = &kexec_crash_image;
 348                 if (kexec_crash_image)
 349                         arch_kexec_unprotect_crashkres();
 350         }
 351
 352         if (flags & KEXEC_FILE_UNLOAD)
 353                 goto exchange;
 354
 355         /*
 356          * In case of crash, new kernel gets loaded in reserved region. It is
 357          * same memory where old crash kernel might be loaded. Free any
 358          * current crash dump kernel before we corrupt it.
 359          */
 360         if (flags & KEXEC_FILE_ON_CRASH)
 361                 kimage_free(xchg(&kexec_crash_image, NULL));
 362
 363         ret = kimage_file_alloc_init(&image, kernel_fd, initrd_fd, cmdline_ptr,
 364                                      cmdline_len, flags);
 365         if (ret)
 366                 goto out;
 367
 368         ret = machine_kexec_prepare(image);
 369         if (ret)
 370                 goto out;
 371
 372         /*
 373          * Some architecture(like S390) may touch the crash memory before
 374          * machine_kexec_prepare(), we must copy vmcoreinfo data after it.
 375          */
 376         ret = kimage_crash_copy_vmcoreinfo(image);
 377         if (ret)
 378                 goto out;
 379
 380         ret = kexec_calculate_store_digests(image);
 381         if (ret)
 382                 goto out;
 383
 384         for (i = 0; i < image->nr_segments; i++) {
 385                 struct kexec_segment *ksegment;
 386
 387                 ksegment = &image->segment[i];
 388                 pr_debug("Loading segment %d: buf=0x%p bufsz=0x%zx mem=0x%lx memsz=0x%zx\n",
 389                          i, ksegment->buf, ksegment->bufsz, ksegment->mem,
 390                          ksegment->memsz);
 391
 392                 ret = kimage_load_segment(image, &image->segment[i]);
 393                 if (ret)
 394                         goto out;
 395         }
 396
 397         kimage_terminate(image);
 398
 399         ret = machine_kexec_post_load(image);
 400         if (ret)
 401                 goto out;
 402
 403         /*
 404          * Free up any temporary buffers allocated which are not needed
 405          * after image has been loaded
 406          */
 407         kimage_file_post_load_cleanup(image);
 408 exchange:
 409         image = xchg(dest_image, image);
 410 out:
 411         if ((flags & KEXEC_FILE_ON_CRASH) && kexec_crash_image)
 412                 arch_kexec_protect_crashkres();
 413
 414         kexec_unlock();
 415         kimage_free(image);
 416         return ret;
 417 }
 418
 419 static int locate_mem_hole_top_down(unsigned long start, unsigned long end,
 420                                     struct kexec_buf *kbuf)
 421 {
 422         struct kimage *image = kbuf->image;
 423         unsigned long temp_start, temp_end;
 424
 425         temp_end = min(end, kbuf->buf_max);
 426         temp_start = temp_end - kbuf->memsz;
 427
 428         do {
 429                 /* align down start */
 430                 temp_start = temp_start & (~(kbuf->buf_align - 1));
 431
 432                 if (temp_start < start || temp_start < kbuf->buf_min)
 433                         return 0;
 434
 435                 temp_end = temp_start + kbuf->memsz - 1;
 436
 437                 /*
 438                  * Make sure this does not conflict with any of existing
 439                  * segments
 440                  */
 441                 if (kimage_is_destination_range(image, temp_start, temp_end)) {
 442                         temp_start = temp_start - PAGE_SIZE;
 443                         continue;
 444                 }
 445
 446                 /* We found a suitable memory range */
 447                 break;
 448         } while (1);
 449
 450         /* If we are here, we found a suitable memory range */
 451         kbuf->mem = temp_start;
 452
 453         /* Success, stop navigating through remaining System RAM ranges */
 454         return 1;
 455 }
 456
 457 static int locate_mem_hole_bottom_up(unsigned long start, unsigned long end,
 458                                      struct kexec_buf *kbuf)
 459 {
 460         struct kimage *image = kbuf->image;
 461         unsigned long temp_start, temp_end;
 462
 463         temp_start = max(start, kbuf->buf_min);
 464
 465         do {
 466                 temp_start = ALIGN(temp_start, kbuf->buf_align);
 467                 temp_end = temp_start + kbuf->memsz - 1;
 468
 469                 if (temp_end > end || temp_end > kbuf->buf_max)
 470                         return 0;
 471                 /*
 472                  * Make sure this does not conflict with any of existing
 473                  * segments
 474                  */
 475                 if (kimage_is_destination_range(image, temp_start, temp_end)) {
 476                         temp_start = temp_start + PAGE_SIZE;
 477                         continue;
 478                 }
 479
 480                 /* We found a suitable memory range */
 481                 break;
 482         } while (1);
 483
 484         /* If we are here, we found a suitable memory range */
 485         kbuf->mem = temp_start;
 486
 487         /* Success, stop navigating through remaining System RAM ranges */
 488         return 1;
 489 }
 490
 491 static int locate_mem_hole_callback(struct resource *res, void *arg)
 492 {
 493         struct kexec_buf *kbuf = (struct kexec_buf *)arg;
 494         u64 start = res->start, end = res->end;
 495         unsigned long sz = end - start + 1;
 496
 497         /* Returning 0 will take to next memory range */
 498
 499         /* Don't use memory that will be detected and handled by a driver. */
 500         if (res->flags & IORESOURCE_SYSRAM_DRIVER_MANAGED)
 501                 return 0;
 502
 503         if (sz < kbuf->memsz)
 504                 return 0;
 505
 506         if (end < kbuf->buf_min || start > kbuf->buf_max)
 507                 return 0;
 508
 509         /*
 510          * Allocate memory top down with-in ram range. Otherwise bottom up
 511          * allocation.
 512          */
 513         if (kbuf->top_down)
 514                 return locate_mem_hole_top_down(start, end, kbuf);
 515         return locate_mem_hole_bottom_up(start, end, kbuf);
 516 }
 517
 518 #ifdef CONFIG_ARCH_KEEP_MEMBLOCK
 519 static int kexec_walk_memblock(struct kexec_buf *kbuf,
 520                                int (*func)(struct resource *, void *))
 521 {
 522         int ret = 0;
 523         u64 i;
 524         phys_addr_t mstart, mend;
 525         struct resource res = { };
 526
 527         if (kbuf->image->type == KEXEC_TYPE_CRASH)
 528                 return func(&crashk_res, kbuf);
 529
 530         /*
 531          * Using MEMBLOCK_NONE will properly skip MEMBLOCK_DRIVER_MANAGED. See
 532          * IORESOURCE_SYSRAM_DRIVER_MANAGED handling in
 533          * locate_mem_hole_callback().
 534          */
 535         if (kbuf->top_down) {
 536                 for_each_free_mem_range_reverse(i, NUMA_NO_NODE, MEMBLOCK_NONE,
 537                                                 &mstart, &mend, NULL) {
 538                         /*
 539                          * In memblock, end points to the first byte after the
 540                          * range while in kexec, end points to the last byte
 541                          * in the range.
 542                          */
 543                         res.start = mstart;
 544                         res.end = mend - 1;
 545                         ret = func(&res, kbuf);
 546                         if (ret)
 547                                 break;
 548                 }
 549         } else {
 550                 for_each_free_mem_range(i, NUMA_NO_NODE, MEMBLOCK_NONE,
 551                                         &mstart, &mend, NULL) {
 552                         /*
 553                          * In memblock, end points to the first byte after the
 554                          * range while in kexec, end points to the last byte
 555                          * in the range.
 556                          */
 557                         res.start = mstart;
 558                         res.end = mend - 1;
 559                         ret = func(&res, kbuf);
 560                         if (ret)
 561                                 break;
 562                 }
 563         }
 564
 565         return ret;
 566 }
 567 #else
 568 static int kexec_walk_memblock(struct kexec_buf *kbuf,
 569                                int (*func)(struct resource *, void *))
 570 {
 571         return 0;
 572 }
 573 #endif
 574
 575 /**
 576  * kexec_walk_resources - call func(data) on free memory regions
 577  * @kbuf:       Context info for the search. Also passed to @func.
 578  * @func:       Function to call for each memory region.
 579  *
 580  * Return: The memory walk will stop when func returns a non-zero value
 581  * and that value will be returned. If all free regions are visited without
 582  * func returning non-zero, then zero will be returned.
 583  */
 584 static int kexec_walk_resources(struct kexec_buf *kbuf,
 585                                 int (*func)(struct resource *, void *))
 586 {
 587         if (kbuf->image->type == KEXEC_TYPE_CRASH)
 588                 return walk_iomem_res_desc(crashk_res.desc,
 589                                            IORESOURCE_SYSTEM_RAM | IORESOURCE_BUSY,
 590                                            crashk_res.start, crashk_res.end,
 591                                            kbuf, func);
 592         else
 593                 return walk_system_ram_res(0, ULONG_MAX, kbuf, func);
 594 }
 595
 596 /**
 597  * kexec_locate_mem_hole - find free memory for the purgatory or the next kernel
 598  * @kbuf:       Parameters for the memory search.
 599  *
 600  * On success, kbuf->mem will have the start address of the memory region found.
 601  *
 602  * Return: 0 on success, negative errno on error.
 603  */
 604 int kexec_locate_mem_hole(struct kexec_buf *kbuf)
 605 {
 606         int ret;
 607
 608         /* Arch knows where to place */
 609         if (kbuf->mem != KEXEC_BUF_MEM_UNKNOWN)
 610                 return 0;
 611
 612         if (!IS_ENABLED(CONFIG_ARCH_KEEP_MEMBLOCK))
 613                 ret = kexec_walk_resources(kbuf, locate_mem_hole_callback);
 614         else
 615                 ret = kexec_walk_memblock(kbuf, locate_mem_hole_callback);
 616
 617         return ret == 1 ? 0 : -EADDRNOTAVAIL;
 618 }
 619
 620 /**
 621  * kexec_add_buffer - place a buffer in a kexec segment
 622  * @kbuf:       Buffer contents and memory parameters.
 623  *
 624  * This function assumes that kexec_mutex is held.
 625  * On successful return, @kbuf->mem will have the physical address of
 626  * the buffer in memory.
 627  *
 628  * Return: 0 on success, negative errno on error.
 629  */
 630 int kexec_add_buffer(struct kexec_buf *kbuf)
 631 {
 632         struct kexec_segment *ksegment;
 633         int ret;
 634
 635         /* Currently adding segment this way is allowed only in file mode */
 636         if (!kbuf->image->file_mode)
 637                 return -EINVAL;
 638
 639         if (kbuf->image->nr_segments >= KEXEC_SEGMENT_MAX)
 640                 return -EINVAL;
 641
 642         /*
 643          * Make sure we are not trying to add buffer after allocating
 644          * control pages. All segments need to be placed first before
 645          * any control pages are allocated. As control page allocation
 646          * logic goes through list of segments to make sure there are
 647          * no destination overlaps.
 648          */
 649         if (!list_empty(&kbuf->image->control_pages)) {
 650                 WARN_ON(1);
 651                 return -EINVAL;
 652         }
 653
 654         /* Ensure minimum alignment needed for segments. */
 655         kbuf->memsz = ALIGN(kbuf->memsz, PAGE_SIZE);
 656         kbuf->buf_align = max(kbuf->buf_align, PAGE_SIZE);
 657
 658         /* Walk the RAM ranges and allocate a suitable range for the buffer */
 659         ret = arch_kexec_locate_mem_hole(kbuf);
 660         if (ret)
 661                 return ret;
 662
 663         /* Found a suitable memory range */
 664         ksegment = &kbuf->image->segment[kbuf->image->nr_segments];
 665         ksegment->kbuf = kbuf->buffer;
 666         ksegment->bufsz = kbuf->bufsz;
 667         ksegment->mem = kbuf->mem;
 668         ksegment->memsz = kbuf->memsz;
 669         kbuf->image->nr_segments++;
 670         return 0;
 671 }
 672
 673 /* Calculate and store the digest of segments */
 674 static int kexec_calculate_store_digests(struct kimage *image)
 675 {
 676         struct crypto_shash *tfm;
 677         struct shash_desc *desc;
 678         int ret = 0, i, j, zero_buf_sz, sha_region_sz;
 679         size_t desc_size, nullsz;
 680         char *digest;
 681         void *zero_buf;
 682         struct kexec_sha_region *sha_regions;
 683         struct purgatory_info *pi = &image->purgatory_info;
 684
 685         if (!IS_ENABLED(CONFIG_ARCH_HAS_KEXEC_PURGATORY))
 686                 return 0;
 687
 688         zero_buf = __va(page_to_pfn(ZERO_PAGE(0)) << PAGE_SHIFT);
 689         zero_buf_sz = PAGE_SIZE;
 690
 691         tfm = crypto_alloc_shash("sha256", 0, 0);
 692         if (IS_ERR(tfm)) {
 693                 ret = PTR_ERR(tfm);
 694                 goto out;
 695         }
 696
 697         desc_size = crypto_shash_descsize(tfm) + sizeof(*desc);
 698         desc = kzalloc(desc_size, GFP_KERNEL);
 699         if (!desc) {
 700                 ret = -ENOMEM;
 701                 goto out_free_tfm;
 702         }
 703
 704         sha_region_sz = KEXEC_SEGMENT_MAX * sizeof(struct kexec_sha_region);
 705         sha_regions = vzalloc(sha_region_sz);
 706         if (!sha_regions) {
 707                 ret = -ENOMEM;
 708                 goto out_free_desc;
 709         }
 710
 711         desc->tfm   = tfm;
 712
 713         ret = crypto_shash_init(desc);
 714         if (ret < 0)
 715                 goto out_free_sha_regions;
 716
 717         digest = kzalloc(SHA256_DIGEST_SIZE, GFP_KERNEL);
 718         if (!digest) {
 719                 ret = -ENOMEM;
 720                 goto out_free_sha_regions;
 721         }
 722
 723         for (j = i = 0; i < image->nr_segments; i++) {
 724                 struct kexec_segment *ksegment;
 725
 726                 ksegment = &image->segment[i];
 727                 /*
 728                  * Skip purgatory as it will be modified once we put digest
 729                  * info in purgatory.
 730                  */
 731                 if (ksegment->kbuf == pi->purgatory_buf)
 732                         continue;
 733
 734                 ret = crypto_shash_update(desc, ksegment->kbuf,
 735                                           ksegment->bufsz);
 736                 if (ret)
 737                         break;
 738
 739                 /*
 740                  * Assume rest of the buffer is filled with zero and
 741                  * update digest accordingly.
 742                  */
 743                 nullsz = ksegment->memsz - ksegment->bufsz;
 744                 while (nullsz) {
 745                         unsigned long bytes = nullsz;
 746
 747                         if (bytes > zero_buf_sz)
 748                                 bytes = zero_buf_sz;
 749                         ret = crypto_shash_update(desc, zero_buf, bytes);
 750                         if (ret)
 751                                 break;
 752                         nullsz -= bytes;
 753                 }
 754
 755                 if (ret)
 756                         break;
 757
 758                 sha_regions[j].start = ksegment->mem;
 759                 sha_regions[j].len = ksegment->memsz;
 760                 j++;
 761         }
 762
 763         if (!ret) {
 764                 ret = crypto_shash_final(desc, digest);
 765                 if (ret)
 766                         goto out_free_digest;
 767                 ret = kexec_purgatory_get_set_symbol(image, "purgatory_sha_regions",
 768                                                      sha_regions, sha_region_sz, 0);
 769                 if (ret)
 770                         goto out_free_digest;
 771
 772                 ret = kexec_purgatory_get_set_symbol(image, "purgatory_sha256_digest",
 773                                                      digest, SHA256_DIGEST_SIZE, 0);
 774                 if (ret)
 775                         goto out_free_digest;
 776         }
 777
 778 out_free_digest:
 779         kfree(digest);
 780 out_free_sha_regions:
 781         vfree(sha_regions);
 782 out_free_desc:
 783         kfree(desc);
 784 out_free_tfm:
 785         kfree(tfm);
 786 out:
 787         return ret;
 788 }
 789
 790 #ifdef CONFIG_ARCH_HAS_KEXEC_PURGATORY
 791 /*
 792  * kexec_purgatory_setup_kbuf - prepare buffer to load purgatory.
 793  * @pi:         Purgatory to be loaded.
 794  * @kbuf:       Buffer to setup.
 795  *
 796  * Allocates the memory needed for the buffer. Caller is responsible to free
 797  * the memory after use.
 798  *
 799  * Return: 0 on success, negative errno on error.
 800  */
 801 static int kexec_purgatory_setup_kbuf(struct purgatory_info *pi,
 802                                       struct kexec_buf *kbuf)
 803 {
 804         const Elf_Shdr *sechdrs;
 805         unsigned long bss_align;
 806         unsigned long bss_sz;
 807         unsigned long align;
 808         int i, ret;
 809
 810         sechdrs = (void *)pi->ehdr + pi->ehdr->e_shoff;
 811         kbuf->buf_align = bss_align = 1;
 812         kbuf->bufsz = bss_sz = 0;
 813
 814         for (i = 0; i < pi->ehdr->e_shnum; i++) {
 815                 if (!(sechdrs[i].sh_flags & SHF_ALLOC))
 816                         continue;
 817
 818                 align = sechdrs[i].sh_addralign;
 819                 if (sechdrs[i].sh_type != SHT_NOBITS) {
 820                         if (kbuf->buf_align < align)
 821                                 kbuf->buf_align = align;
 822                         kbuf->bufsz = ALIGN(kbuf->bufsz, align);
 823                         kbuf->bufsz += sechdrs[i].sh_size;
 824                 } else {
 825                         if (bss_align < align)
 826                                 bss_align = align;
 827                         bss_sz = ALIGN(bss_sz, align);
 828                         bss_sz += sechdrs[i].sh_size;
 829                 }
 830         }
 831         kbuf->bufsz = ALIGN(kbuf->bufsz, bss_align);
 832         kbuf->memsz = kbuf->bufsz + bss_sz;
 833         if (kbuf->buf_align < bss_align)
 834                 kbuf->buf_align = bss_align;
 835
 836         kbuf->buffer = vzalloc(kbuf->bufsz);
 837         if (!kbuf->buffer)
 838                 return -ENOMEM;
 839         pi->purgatory_buf = kbuf->buffer;
 840
 841         ret = kexec_add_buffer(kbuf);
 842         if (ret)
 843                 goto out;
 844
 845         return 0;
 846 out:
 847         vfree(pi->purgatory_buf);
 848         pi->purgatory_buf = NULL;
 849         return ret;
 850 }
 851
 852 /*
 853  * kexec_purgatory_setup_sechdrs - prepares the pi->sechdrs buffer.
 854  * @pi:         Purgatory to be loaded.
 855  * @kbuf:       Buffer prepared to store purgatory.
 856  *
 857  * Allocates the memory needed for the buffer. Caller is responsible to free
 858  * the memory after use.
 859  *
 860  * Return: 0 on success, negative errno on error.
 861  */
 862 static int kexec_purgatory_setup_sechdrs(struct purgatory_info *pi,
 863                                          struct kexec_buf *kbuf)
 864 {
 865         unsigned long bss_addr;
 866         unsigned long offset;
 867         Elf_Shdr *sechdrs;
 868         int i;
 869
 870         /*
 871          * The section headers in kexec_purgatory are read-only. In order to
 872          * have them modifiable make a temporary copy.
 873          */
 874         sechdrs = vzalloc(array_size(sizeof(Elf_Shdr), pi->ehdr->e_shnum));
 875         if (!sechdrs)
 876                 return -ENOMEM;
 877         memcpy(sechdrs, (void *)pi->ehdr + pi->ehdr->e_shoff,
 878                pi->ehdr->e_shnum * sizeof(Elf_Shdr));
 879         pi->sechdrs = sechdrs;
 880
 881         offset = 0;
 882         bss_addr = kbuf->mem + kbuf->bufsz;
 883         kbuf->image->start = pi->ehdr->e_entry;
 884
 885         for (i = 0; i < pi->ehdr->e_shnum; i++) {
 886                 unsigned long align;
 887                 void *src, *dst;
 888
 889                 if (!(sechdrs[i].sh_flags & SHF_ALLOC))
 890                         continue;
 891
 892                 align = sechdrs[i].sh_addralign;
 893                 if (sechdrs[i].sh_type == SHT_NOBITS) {
 894                         bss_addr = ALIGN(bss_addr, align);
 895                         sechdrs[i].sh_addr = bss_addr;
 896                         bss_addr += sechdrs[i].sh_size;
 897                         continue;
 898                 }
 899
 900                 offset = ALIGN(offset, align);
 901
 902                 /*
 903                  * Check if the segment contains the entry point, if so,
 904                  * calculate the value of image->start based on it.
 905                  * If the compiler has produced more than one .text section
 906                  * (Eg: .text.hot), they are generally after the main .text
 907                  * section, and they shall not be used to calculate
 908                  * image->start. So do not re-calculate image->start if it
 909                  * is not set to the initial value, and warn the user so they
 910                  * have a chance to fix their purgatory's linker script.
 911                  */
 912                 if (sechdrs[i].sh_flags & SHF_EXECINSTR &&
 913                     pi->ehdr->e_entry >= sechdrs[i].sh_addr &&
 914                     pi->ehdr->e_entry < (sechdrs[i].sh_addr
 915                                          + sechdrs[i].sh_size) &&
 916                     !WARN_ON(kbuf->image->start != pi->ehdr->e_entry)) {
 917                         kbuf->image->start -= sechdrs[i].sh_addr;
 918                         kbuf->image->start += kbuf->mem + offset;
 919                 }
 920
 921                 src = (void *)pi->ehdr + sechdrs[i].sh_offset;
 922                 dst = pi->purgatory_buf + offset;
 923                 memcpy(dst, src, sechdrs[i].sh_size);
 924
 925                 sechdrs[i].sh_addr = kbuf->mem + offset;
 926                 sechdrs[i].sh_offset = offset;
 927                 offset += sechdrs[i].sh_size;
 928         }
 929
 930         return 0;
 931 }
 932
 933 static int kexec_apply_relocations(struct kimage *image)
 934 {
 935         int i, ret;
 936         struct purgatory_info *pi = &image->purgatory_info;
 937         const Elf_Shdr *sechdrs;
 938
 939         sechdrs = (void *)pi->ehdr + pi->ehdr->e_shoff;
 940
 941         for (i = 0; i < pi->ehdr->e_shnum; i++) {
 942                 const Elf_Shdr *relsec;
 943                 const Elf_Shdr *symtab;
 944                 Elf_Shdr *section;
 945
 946                 relsec = sechdrs + i;
 947
 948                 if (relsec->sh_type != SHT_RELA &&
 949                     relsec->sh_type != SHT_REL)
 950                         continue;
 951
 952                 /*
 953                  * For section of type SHT_RELA/SHT_REL,
 954                  * ->sh_link contains section header index of associated
 955                  * symbol table. And ->sh_info contains section header
 956                  * index of section to which relocations apply.
 957                  */
 958                 if (relsec->sh_info >= pi->ehdr->e_shnum ||
 959                     relsec->sh_link >= pi->ehdr->e_shnum)
 960                         return -ENOEXEC;
 961
 962                 section = pi->sechdrs + relsec->sh_info;
 963                 symtab = sechdrs + relsec->sh_link;
 964
 965                 if (!(section->sh_flags & SHF_ALLOC))
 966                         continue;
 967
 968                 /*
 969                  * symtab->sh_link contain section header index of associated
 970                  * string table.
 971                  */
 972                 if (symtab->sh_link >= pi->ehdr->e_shnum)
 973                         /* Invalid section number? */
 974                         continue;
 975
 976                 /*
 977                  * Respective architecture needs to provide support for applying
 978                  * relocations of type SHT_RELA/SHT_REL.
 979                  */
 980                 if (relsec->sh_type == SHT_RELA)
 981                         ret = arch_kexec_apply_relocations_add(pi, section,
 982                                                                relsec, symtab);
 983                 else if (relsec->sh_type == SHT_REL)
 984                         ret = arch_kexec_apply_relocations(pi, section,
 985                                                            relsec, symtab);
 986                 if (ret)
 987                         return ret;
 988         }
 989
 990         return 0;
 991 }
 992
 993 /*
 994  * kexec_load_purgatory - Load and relocate the purgatory object.
 995  * @image:      Image to add the purgatory to.
 996  * @kbuf:       Memory parameters to use.
 997  *
 998  * Allocates the memory needed for image->purgatory_info.sechdrs and
 999  * image->purgatory_info.purgatory_buf/kbuf->buffer. Caller is responsible
1000  * to free the memory after use.
1001  *
1002  * Return: 0 on success, negative errno on error.
1003  */
1004 int kexec_load_purgatory(struct kimage *image, struct kexec_buf *kbuf)
1005 {
1006         struct purgatory_info *pi = &image->purgatory_info;
1007         int ret;
1008
1009         if (kexec_purgatory_size <= 0)
1010                 return -EINVAL;
1011
1012         pi->ehdr = (const Elf_Ehdr *)kexec_purgatory;
1013
1014         ret = kexec_purgatory_setup_kbuf(pi, kbuf);
1015         if (ret)
1016                 return ret;
1017
1018         ret = kexec_purgatory_setup_sechdrs(pi, kbuf);
1019         if (ret)
1020                 goto out_free_kbuf;
1021
1022         ret = kexec_apply_relocations(image);
1023         if (ret)
1024                 goto out;
1025
1026         return 0;
1027 out:
1028         vfree(pi->sechdrs);
1029         pi->sechdrs = NULL;
1030 out_free_kbuf:
1031         vfree(pi->purgatory_buf);
1032         pi->purgatory_buf = NULL;
1033         return ret;
1034 }
1035
1036 /*
1037  * kexec_purgatory_find_symbol - find a symbol in the purgatory
1038  * @pi:         Purgatory to search in.
1039  * @name:       Name of the symbol.
1040  *
1041  * Return: pointer to symbol in read-only symtab on success, NULL on error.
1042  */
1043 static const Elf_Sym *kexec_purgatory_find_symbol(struct purgatory_info *pi,
1044                                                   const char *name)
1045 {
1046         const Elf_Shdr *sechdrs;
1047         const Elf_Ehdr *ehdr;
1048         const Elf_Sym *syms;
1049         const char *strtab;
1050         int i, k;
1051
1052         if (!pi->ehdr)
1053                 return NULL;
1054
1055         ehdr = pi->ehdr;
1056         sechdrs = (void *)ehdr + ehdr->e_shoff;
1057
1058         for (i = 0; i < ehdr->e_shnum; i++) {
1059                 if (sechdrs[i].sh_type != SHT_SYMTAB)
1060                         continue;
1061
1062                 if (sechdrs[i].sh_link >= ehdr->e_shnum)
1063                         /* Invalid strtab section number */
1064                         continue;
1065                 strtab = (void *)ehdr + sechdrs[sechdrs[i].sh_link].sh_offset;
1066                 syms = (void *)ehdr + sechdrs[i].sh_offset;
1067
1068                 /* Go through symbols for a match */
1069                 for (k = 0; k < sechdrs[i].sh_size/sizeof(Elf_Sym); k++) {
1070                         if (ELF_ST_BIND(syms[k].st_info) != STB_GLOBAL)
1071                                 continue;
1072
1073                         if (strcmp(strtab + syms[k].st_name, name) != 0)
1074                                 continue;
1075
1076                         if (syms[k].st_shndx == SHN_UNDEF ||
1077                             syms[k].st_shndx >= ehdr->e_shnum) {
1078                                 pr_debug("Symbol: %s has bad section index %d.\n",
1079                                                 name, syms[k].st_shndx);
1080                                 return NULL;
1081                         }
1082
1083                         /* Found the symbol we are looking for */
1084                         return &syms[k];
1085                 }
1086         }
1087
1088         return NULL;
1089 }
1090
1091 void *kexec_purgatory_get_symbol_addr(struct kimage *image, const char *name)
1092 {
1093         struct purgatory_info *pi = &image->purgatory_info;
1094         const Elf_Sym *sym;
1095         Elf_Shdr *sechdr;
1096
1097         sym = kexec_purgatory_find_symbol(pi, name);
1098         if (!sym)
1099                 return ERR_PTR(-EINVAL);
1100
1101         sechdr = &pi->sechdrs[sym->st_shndx];
1102
1103         /*
1104          * Returns the address where symbol will finally be loaded after
1105          * kexec_load_segment()
1106          */
1107         return (void *)(sechdr->sh_addr + sym->st_value);
1108 }
1109
1110 /*
1111  * Get or set value of a symbol. If "get_value" is true, symbol value is
1112  * returned in buf otherwise symbol value is set based on value in buf.
1113  */
1114 int kexec_purgatory_get_set_symbol(struct kimage *image, const char *name,
1115                                    void *buf, unsigned int size, bool get_value)
1116 {
1117         struct purgatory_info *pi = &image->purgatory_info;
1118         const Elf_Sym *sym;
1119         Elf_Shdr *sec;
1120         char *sym_buf;
1121
1122         sym = kexec_purgatory_find_symbol(pi, name);
1123         if (!sym)
1124                 return -EINVAL;
1125
1126         if (sym->st_size != size) {
1127                 pr_err("symbol %s size mismatch: expected %lu actual %u\n",
1128                        name, (unsigned long)sym->st_size, size);
1129                 return -EINVAL;
1130         }
1131
1132         sec = pi->sechdrs + sym->st_shndx;
1133
1134         if (sec->sh_type == SHT_NOBITS) {
1135                 pr_err("symbol %s is in a bss section. Cannot %s\n", name,
1136                        get_value ? "get" : "set");
1137                 return -EINVAL;
1138         }
1139
1140         sym_buf = (char *)pi->purgatory_buf + sec->sh_offset + sym->st_value;
1141
1142         if (get_value)
1143                 memcpy((void *)buf, sym_buf, size);
1144         else
1145                 memcpy((void *)sym_buf, buf, size);
1146
1147         return 0;
1148 }
1149 #endif /* CONFIG_ARCH_HAS_KEXEC_PURGATORY */
1150
1151 int crash_exclude_mem_range(struct crash_mem *mem,
1152                             unsigned long long mstart, unsigned long long mend)
1153 {
1154         int i, j;
1155         unsigned long long start, end, p_start, p_end;
1156         struct crash_mem_range temp_range = {0, 0};
1157
1158         for (i = 0; i < mem->nr_ranges; i++) {
1159                 start = mem->ranges[i].start;
1160                 end = mem->ranges[i].end;
1161                 p_start = mstart;
1162                 p_end = mend;
1163
1164                 if (mstart > end || mend < start)
1165                         continue;
1166
1167                 /* Truncate any area outside of range */
1168                 if (mstart < start)
1169                         p_start = start;
1170                 if (mend > end)
1171                         p_end = end;
1172
1173                 /* Found completely overlapping range */
1174                 if (p_start == start && p_end == end) {
1175                         mem->ranges[i].start = 0;
1176                         mem->ranges[i].end = 0;
1177                         if (i < mem->nr_ranges - 1) {
1178                                 /* Shift rest of the ranges to left */
1179                                 for (j = i; j < mem->nr_ranges - 1; j++) {
1180                                         mem->ranges[j].start =
1181                                                 mem->ranges[j+1].start;
1182                                         mem->ranges[j].end =
1183                                                         mem->ranges[j+1].end;
1184                                 }
1185
1186                                 /*
1187                                  * Continue to check if there are another overlapping ranges
1188                                  * from the current position because of shifting the above
1189                                  * mem ranges.
1190                                  */
1191                                 i--;
1192                                 mem->nr_ranges--;
1193                                 continue;
1194                         }
1195                         mem->nr_ranges--;
1196                         return 0;
1197                 }
1198
1199                 if (p_start > start && p_end < end) {
1200                         /* Split original range */
1201                         mem->ranges[i].end = p_start - 1;
1202                         temp_range.start = p_end + 1;
1203                         temp_range.end = end;
1204                 } else if (p_start != start)
1205                         mem->ranges[i].end = p_start - 1;
1206                 else
1207                         mem->ranges[i].start = p_end + 1;
1208                 break;
1209         }
1210
1211         /* If a split happened, add the split to array */
1212         if (!temp_range.end)
1213                 return 0;
1214
1215         /* Split happened */
1216         if (i == mem->max_nr_ranges - 1)
1217                 return -ENOMEM;
1218
1219         /* Location where new range should go */
1220         j = i + 1;
1221         if (j < mem->nr_ranges) {
1222                 /* Move over all ranges one slot towards the end */
1223                 for (i = mem->nr_ranges - 1; i >= j; i--)
1224                         mem->ranges[i + 1] = mem->ranges[i];
1225         }
1226
1227         mem->ranges[j].start = temp_range.start;
1228         mem->ranges[j].end = temp_range.end;
1229         mem->nr_ranges++;
1230         return 0;
1231 }
1232
1233 int crash_prepare_elf64_headers(struct crash_mem *mem, int need_kernel_map,
1234                           void **addr, unsigned long *sz)
1235 {
1236         Elf64_Ehdr *ehdr;
1237         Elf64_Phdr *phdr;
1238         unsigned long nr_cpus = num_possible_cpus(), nr_phdr, elf_sz;
1239         unsigned char *buf;
1240         unsigned int cpu, i;
1241         unsigned long long notes_addr;
1242         unsigned long mstart, mend;
1243
1244         /* extra phdr for vmcoreinfo ELF note */
1245         nr_phdr = nr_cpus + 1;
1246         nr_phdr += mem->nr_ranges;
1247
1248         /*
1249          * kexec-tools creates an extra PT_LOAD phdr for kernel text mapping
1250          * area (for example, ffffffff80000000 - ffffffffa0000000 on x86_64).
1251          * I think this is required by tools like gdb. So same physical
1252          * memory will be mapped in two ELF headers. One will contain kernel
1253          * text virtual addresses and other will have __va(physical) addresses.
1254          */
1255
1256         nr_phdr++;
1257         elf_sz = sizeof(Elf64_Ehdr) + nr_phdr * sizeof(Elf64_Phdr);
1258         elf_sz = ALIGN(elf_sz, ELF_CORE_HEADER_ALIGN);
1259
1260         buf = vzalloc(elf_sz);
1261         if (!buf)
1262                 return -ENOMEM;
1263
1264         ehdr = (Elf64_Ehdr *)buf;
1265         phdr = (Elf64_Phdr *)(ehdr + 1);
1266         memcpy(ehdr->e_ident, ELFMAG, SELFMAG);
1267         ehdr->e_ident[EI_CLASS] = ELFCLASS64;
1268         ehdr->e_ident[EI_DATA] = ELFDATA2LSB;
1269         ehdr->e_ident[EI_VERSION] = EV_CURRENT;
1270         ehdr->e_ident[EI_OSABI] = ELF_OSABI;
1271         memset(ehdr->e_ident + EI_PAD, 0, EI_NIDENT - EI_PAD);
1272         ehdr->e_type = ET_CORE;
1273         ehdr->e_machine = ELF_ARCH;
1274         ehdr->e_version = EV_CURRENT;
1275         ehdr->e_phoff = sizeof(Elf64_Ehdr);
1276         ehdr->e_ehsize = sizeof(Elf64_Ehdr);
1277         ehdr->e_phentsize = sizeof(Elf64_Phdr);
1278
1279         /* Prepare one phdr of type PT_NOTE for each present CPU */
1280         for_each_present_cpu(cpu) {
1281                 phdr->p_type = PT_NOTE;
1282                 notes_addr = per_cpu_ptr_to_phys(per_cpu_ptr(crash_notes, cpu));
1283                 phdr->p_offset = phdr->p_paddr = notes_addr;
1284                 phdr->p_filesz = phdr->p_memsz = sizeof(note_buf_t);
1285                 (ehdr->e_phnum)++;
1286                 phdr++;
1287         }
1288
1289         /* Prepare one PT_NOTE header for vmcoreinfo */
1290         phdr->p_type = PT_NOTE;
1291         phdr->p_offset = phdr->p_paddr = paddr_vmcoreinfo_note();
1292         phdr->p_filesz = phdr->p_memsz = VMCOREINFO_NOTE_SIZE;
1293         (ehdr->e_phnum)++;
1294         phdr++;
1295
1296         /* Prepare PT_LOAD type program header for kernel text region */
1297         if (need_kernel_map) {
1298                 phdr->p_type = PT_LOAD;
1299                 phdr->p_flags = PF_R|PF_W|PF_X;
1300                 phdr->p_vaddr = (unsigned long) _text;
1301                 phdr->p_filesz = phdr->p_memsz = _end - _text;
1302                 phdr->p_offset = phdr->p_paddr = __pa_symbol(_text);
1303                 ehdr->e_phnum++;
1304                 phdr++;
1305         }
1306
1307         /* Go through all the ranges in mem->ranges[] and prepare phdr */
1308         for (i = 0; i < mem->nr_ranges; i++) {
1309                 mstart = mem->ranges[i].start;
1310                 mend = mem->ranges[i].end;
1311
1312                 phdr->p_type = PT_LOAD;
1313                 phdr->p_flags = PF_R|PF_W|PF_X;
1314                 phdr->p_offset  = mstart;
1315
1316                 phdr->p_paddr = mstart;
1317                 phdr->p_vaddr = (unsigned long) __va(mstart);
1318                 phdr->p_filesz = phdr->p_memsz = mend - mstart + 1;
1319                 phdr->p_align = 0;
1320                 ehdr->e_phnum++;
1321                 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",
1322                         phdr, phdr->p_vaddr, phdr->p_paddr, phdr->p_filesz,
1323                         ehdr->e_phnum, phdr->p_offset);
1324                 phdr++;
1325         }
1326
1327         *addr = buf;
1328         *sz = elf_sz;
1329         return 0;
1330 }