kernel/kexec_file.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  * kexec: kexec_file_load system call
   4  *
   5  * Copyright (C) 2014 Red Hat Inc.
   6  * Authors:
   7  *      Vivek Goyal <vgoyal@redhat.com>
   8  */
   9
  10 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
  11
  12 #include <linux/capability.h>
  13 #include <linux/mm.h>
  14 #include <linux/file.h>
  15 #include <linux/slab.h>
  16 #include <linux/kexec.h>
  17 #include <linux/memblock.h>
  18 #include <linux/mutex.h>
  19 #include <linux/list.h>
  20 #include <linux/fs.h>
  21 #include <linux/ima.h>
  22 #include <crypto/hash.h>
  23 #include <crypto/sha.h>
  24 #include <linux/elf.h>
  25 #include <linux/elfcore.h>
  26 #include <linux/kernel.h>
  27 #include <linux/syscalls.h>
  28 #include <linux/vmalloc.h>
  29 #include "kexec_internal.h"
  30
  31 static int kexec_calculate_store_digests(struct kimage *image);
  32
  33 /*
  34  * Currently this is the only default function that is exported as some
  35  * architectures need it to do additional handlings.
  36  * In the future, other default functions may be exported too if required.
  37  */
  38 int kexec_image_probe_default(struct kimage *image, void *buf,
  39                               unsigned long buf_len)
  40 {
  41         const struct kexec_file_ops * const *fops;
  42         int ret = -ENOEXEC;
  43
  44         for (fops = &kexec_file_loaders[0]; *fops && (*fops)->probe; ++fops) {
  45                 ret = (*fops)->probe(buf, buf_len);
  46                 if (!ret) {
  47                         image->fops = *fops;
  48                         return ret;
  49                 }
  50         }
  51
  52         return ret;
  53 }
  54
  55 /* Architectures can provide this probe function */
  56 int __weak arch_kexec_kernel_image_probe(struct kimage *image, void *buf,
  57                                          unsigned long buf_len)
  58 {
  59         return kexec_image_probe_default(image, buf, buf_len);
  60 }
  61
  62 static void *kexec_image_load_default(struct kimage *image)
  63 {
  64         if (!image->fops || !image->fops->load)
  65                 return ERR_PTR(-ENOEXEC);
  66
  67         return image->fops->load(image, image->kernel_buf,
  68                                  image->kernel_buf_len, image->initrd_buf,
  69                                  image->initrd_buf_len, image->cmdline_buf,
  70                                  image->cmdline_buf_len);
  71 }
  72
  73 void * __weak arch_kexec_kernel_image_load(struct kimage *image)
  74 {
  75         return kexec_image_load_default(image);
  76 }
  77
  78 int kexec_image_post_load_cleanup_default(struct kimage *image)
  79 {
  80         if (!image->fops || !image->fops->cleanup)
  81                 return 0;
  82
  83         return image->fops->cleanup(image->image_loader_data);
  84 }
  85
  86 int __weak arch_kimage_file_post_load_cleanup(struct kimage *image)
  87 {
  88         return kexec_image_post_load_cleanup_default(image);
  89 }
  90
  91 #ifdef CONFIG_KEXEC_SIG
  92 static int kexec_image_verify_sig_default(struct kimage *image, void *buf,
  93                                           unsigned long buf_len)
  94 {
  95         if (!image->fops || !image->fops->verify_sig) {
  96                 pr_debug("kernel loader does not support signature verification.\n");
  97                 return -EKEYREJECTED;
  98         }
  99
 100         return image->fops->verify_sig(buf, buf_len);
 101 }
 102
 103 int __weak arch_kexec_kernel_verify_sig(struct kimage *image, void *buf,
 104                                         unsigned long buf_len)
 105 {
 106         return kexec_image_verify_sig_default(image, buf, buf_len);
 107 }
 108 #endif
 109
 110 /*
 111  * arch_kexec_apply_relocations_add - apply relocations of type RELA
 112  * @pi:         Purgatory to be relocated.
 113  * @section:    Section relocations applying to.
 114  * @relsec:     Section containing RELAs.
 115  * @symtab:     Corresponding symtab.
 116  *
 117  * Return: 0 on success, negative errno on error.
 118  */
 119 int __weak
 120 arch_kexec_apply_relocations_add(struct purgatory_info *pi, Elf_Shdr *section,
 121                                  const Elf_Shdr *relsec, const Elf_Shdr *symtab)
 122 {
 123         pr_err("RELA relocation unsupported.\n");
 124         return -ENOEXEC;
 125 }
 126
 127 /*
 128  * arch_kexec_apply_relocations - apply relocations of type REL
 129  * @pi:         Purgatory to be relocated.
 130  * @section:    Section relocations applying to.
 131  * @relsec:     Section containing RELs.
 132  * @symtab:     Corresponding symtab.
 133  *
 134  * Return: 0 on success, negative errno on error.
 135  */
 136 int __weak
 137 arch_kexec_apply_relocations(struct purgatory_info *pi, Elf_Shdr *section,
 138                              const Elf_Shdr *relsec, const Elf_Shdr *symtab)
 139 {
 140         pr_err("REL relocation unsupported.\n");
 141         return -ENOEXEC;
 142 }
 143
 144 /*
 145  * Free up memory used by kernel, initrd, and command line. This is temporary
 146  * memory allocation which is not needed any more after these buffers have
 147  * been loaded into separate segments and have been copied elsewhere.
 148  */
 149 void kimage_file_post_load_cleanup(struct kimage *image)
 150 {
 151         struct purgatory_info *pi = &image->purgatory_info;
 152
 153         vfree(image->kernel_buf);
 154         image->kernel_buf = NULL;
 155
 156         vfree(image->initrd_buf);
 157         image->initrd_buf = NULL;
 158
 159         kfree(image->cmdline_buf);
 160         image->cmdline_buf = NULL;
 161
 162         vfree(pi->purgatory_buf);
 163         pi->purgatory_buf = NULL;
 164
 165         vfree(pi->sechdrs);
 166         pi->sechdrs = NULL;
 167
 168         /* See if architecture has anything to cleanup post load */
 169         arch_kimage_file_post_load_cleanup(image);
 170
 171         /*
 172          * Above call should have called into bootloader to free up
 173          * any data stored in kimage->image_loader_data. It should
 174          * be ok now to free it up.
 175          */
 176         kfree(image->image_loader_data);
 177         image->image_loader_data = NULL;
 178 }
 179
 180 #ifdef CONFIG_KEXEC_SIG
 181 static int
 182 kimage_validate_signature(struct kimage *image)
 183 {
 184         int ret;
 185
 186         ret = arch_kexec_kernel_verify_sig(image, image->kernel_buf,
 187                                            image->kernel_buf_len);
 188         if (ret) {
 189
 190                 if (IS_ENABLED(CONFIG_KEXEC_SIG_FORCE)) {
 191                         pr_notice("Enforced kernel signature verification failed (%d).\n", ret);
 192                         return ret;
 193                 }
 194
 195                 /*
 196                  * If IMA is guaranteed to appraise a signature on the kexec
 197                  * image, permit it even if the kernel is otherwise locked
 198                  * down.
 199                  */
 200                 if (!ima_appraise_signature(READING_KEXEC_IMAGE) &&
 201                     security_locked_down(LOCKDOWN_KEXEC))
 202                         return -EPERM;
 203
 204                 pr_debug("kernel signature verification failed (%d).\n", ret);
 205         }
 206
 207         return 0;
 208 }
 209 #endif
 210
 211 /*
 212  * In file mode list of segments is prepared by kernel. Copy relevant
 213  * data from user space, do error checking, prepare segment list
 214  */
 215 static int
 216 kimage_file_prepare_segments(struct kimage *image, int kernel_fd, int initrd_fd,
 217                              const char __user *cmdline_ptr,
 218                              unsigned long cmdline_len, unsigned flags)
 219 {
 220         int ret;
 221         void *ldata;
 222         loff_t size;
 223
 224         ret = kernel_read_file_from_fd(kernel_fd, &image->kernel_buf,
 225                                        &size, INT_MAX, READING_KEXEC_IMAGE);
 226         if (ret)
 227                 return ret;
 228         image->kernel_buf_len = size;
 229
 230         /* Call arch image probe handlers */
 231         ret = arch_kexec_kernel_image_probe(image, image->kernel_buf,
 232                                             image->kernel_buf_len);
 233         if (ret)
 234                 goto out;
 235
 236 #ifdef CONFIG_KEXEC_SIG
 237         ret = kimage_validate_signature(image);
 238
 239         if (ret)
 240                 goto out;
 241 #endif
 242         /* It is possible that there no initramfs is being loaded */
 243         if (!(flags & KEXEC_FILE_NO_INITRAMFS)) {
 244                 ret = kernel_read_file_from_fd(initrd_fd, &image->initrd_buf,
 245                                                &size, INT_MAX,
 246                                                READING_KEXEC_INITRAMFS);
 247                 if (ret)
 248                         goto out;
 249                 image->initrd_buf_len = size;
 250         }
 251
 252         if (cmdline_len) {
 253                 image->cmdline_buf = memdup_user(cmdline_ptr, cmdline_len);
 254                 if (IS_ERR(image->cmdline_buf)) {
 255                         ret = PTR_ERR(image->cmdline_buf);
 256                         image->cmdline_buf = NULL;
 257                         goto out;
 258                 }
 259
 260                 image->cmdline_buf_len = cmdline_len;
 261
 262                 /* command line should be a string with last byte null */
 263                 if (image->cmdline_buf[cmdline_len - 1] != '\0') {
 264                         ret = -EINVAL;
 265                         goto out;
 266                 }
 267
 268                 ima_kexec_cmdline(image->cmdline_buf,
 269                                   image->cmdline_buf_len - 1);
 270         }
 271
 272         /* IMA needs to pass the measurement list to the next kernel. */
 273         ima_add_kexec_buffer(image);
 274
 275         /* Call arch image load handlers */
 276         ldata = arch_kexec_kernel_image_load(image);
 277
 278         if (IS_ERR(ldata)) {
 279                 ret = PTR_ERR(ldata);
 280                 goto out;
 281         }
 282
 283         image->image_loader_data = ldata;
 284 out:
 285         /* In case of error, free up all allocated memory in this function */
 286         if (ret)
 287                 kimage_file_post_load_cleanup(image);
 288         return ret;
 289 }
 290
 291 static int
 292 kimage_file_alloc_init(struct kimage **rimage, int kernel_fd,
 293                        int initrd_fd, const char __user *cmdline_ptr,
 294                        unsigned long cmdline_len, unsigned long flags)
 295 {
 296         int ret;
 297         struct kimage *image;
 298         bool kexec_on_panic = flags & KEXEC_FILE_ON_CRASH;
 299
 300         image = do_kimage_alloc_init();
 301         if (!image)
 302                 return -ENOMEM;
 303
 304         image->file_mode = 1;
 305
 306         if (kexec_on_panic) {
 307                 /* Enable special crash kernel control page alloc policy. */
 308                 image->control_page = crashk_res.start;
 309                 image->type = KEXEC_TYPE_CRASH;
 310         }
 311
 312         ret = kimage_file_prepare_segments(image, kernel_fd, initrd_fd,
 313                                            cmdline_ptr, cmdline_len, flags);
 314         if (ret)
 315                 goto out_free_image;
 316
 317         ret = sanity_check_segment_list(image);
 318         if (ret)
 319                 goto out_free_post_load_bufs;
 320
 321         ret = -ENOMEM;
 322         image->control_code_page = kimage_alloc_control_pages(image,
 323                                            get_order(KEXEC_CONTROL_PAGE_SIZE));
 324         if (!image->control_code_page) {
 325                 pr_err("Could not allocate control_code_buffer\n");
 326                 goto out_free_post_load_bufs;
 327         }
 328
 329         if (!kexec_on_panic) {
 330                 image->swap_page = kimage_alloc_control_pages(image, 0);
 331                 if (!image->swap_page) {
 332                         pr_err("Could not allocate swap buffer\n");
 333                         goto out_free_control_pages;
 334                 }
 335         }
 336
 337         *rimage = image;
 338         return 0;
 339 out_free_control_pages:
 340         kimage_free_page_list(&image->control_pages);
 341 out_free_post_load_bufs:
 342         kimage_file_post_load_cleanup(image);
 343 out_free_image:
 344         kfree(image);
 345         return ret;
 346 }
 347
 348 SYSCALL_DEFINE5(kexec_file_load, int, kernel_fd, int, initrd_fd,
 349                 unsigned long, cmdline_len, const char __user *, cmdline_ptr,
 350                 unsigned long, flags)
 351 {
 352         int ret = 0, i;
 353         struct kimage **dest_image, *image;
 354
 355         /* We only trust the superuser with rebooting the system. */
 356         if (!capable(CAP_SYS_BOOT) || kexec_load_disabled)
 357                 return -EPERM;
 358
 359         /* Make sure we have a legal set of flags */
 360         if (flags != (flags & KEXEC_FILE_FLAGS))
 361                 return -EINVAL;
 362
 363         image = NULL;
 364
 365         if (!mutex_trylock(&kexec_mutex))
 366                 return -EBUSY;
 367
 368         dest_image = &kexec_image;
 369         if (flags & KEXEC_FILE_ON_CRASH) {
 370                 dest_image = &kexec_crash_image;
 371                 if (kexec_crash_image)
 372                         arch_kexec_unprotect_crashkres();
 373         }
 374
 375         if (flags & KEXEC_FILE_UNLOAD)
 376                 goto exchange;
 377
 378         /*
 379          * In case of crash, new kernel gets loaded in reserved region. It is
 380          * same memory where old crash kernel might be loaded. Free any
 381          * current crash dump kernel before we corrupt it.
 382          */
 383         if (flags & KEXEC_FILE_ON_CRASH)
 384                 kimage_free(xchg(&kexec_crash_image, NULL));
 385
 386         ret = kimage_file_alloc_init(&image, kernel_fd, initrd_fd, cmdline_ptr,
 387                                      cmdline_len, flags);
 388         if (ret)
 389                 goto out;
 390
 391         ret = machine_kexec_prepare(image);
 392         if (ret)
 393                 goto out;
 394
 395         /*
 396          * Some architecture(like S390) may touch the crash memory before
 397          * machine_kexec_prepare(), we must copy vmcoreinfo data after it.
 398          */
 399         ret = kimage_crash_copy_vmcoreinfo(image);
 400         if (ret)
 401                 goto out;
 402
 403         ret = kexec_calculate_store_digests(image);
 404         if (ret)
 405                 goto out;
 406
 407         for (i = 0; i < image->nr_segments; i++) {
 408                 struct kexec_segment *ksegment;
 409
 410                 ksegment = &image->segment[i];
 411                 pr_debug("Loading segment %d: buf=0x%p bufsz=0x%zx mem=0x%lx memsz=0x%zx\n",
 412                          i, ksegment->buf, ksegment->bufsz, ksegment->mem,
 413                          ksegment->memsz);
 414
 415                 ret = kimage_load_segment(image, &image->segment[i]);
 416                 if (ret)
 417                         goto out;
 418         }
 419
 420         kimage_terminate(image);
 421
 422         ret = machine_kexec_post_load(image);
 423         if (ret)
 424                 goto out;
 425
 426         /*
 427          * Free up any temporary buffers allocated which are not needed
 428          * after image has been loaded
 429          */
 430         kimage_file_post_load_cleanup(image);
 431 exchange:
 432         image = xchg(dest_image, image);
 433 out:
 434         if ((flags & KEXEC_FILE_ON_CRASH) && kexec_crash_image)
 435                 arch_kexec_protect_crashkres();
 436
 437         mutex_unlock(&kexec_mutex);
 438         kimage_free(image);
 439         return ret;
 440 }
 441
 442 static int locate_mem_hole_top_down(unsigned long start, unsigned long end,
 443                                     struct kexec_buf *kbuf)
 444 {
 445         struct kimage *image = kbuf->image;
 446         unsigned long temp_start, temp_end;
 447
 448         temp_end = min(end, kbuf->buf_max);
 449         temp_start = temp_end - kbuf->memsz;
 450
 451         do {
 452                 /* align down start */
 453                 temp_start = temp_start & (~(kbuf->buf_align - 1));
 454
 455                 if (temp_start < start || temp_start < kbuf->buf_min)
 456                         return 0;
 457
 458                 temp_end = temp_start + kbuf->memsz - 1;
 459
 460                 /*
 461                  * Make sure this does not conflict with any of existing
 462                  * segments
 463                  */
 464                 if (kimage_is_destination_range(image, temp_start, temp_end)) {
 465                         temp_start = temp_start - PAGE_SIZE;
 466                         continue;
 467                 }
 468
 469                 /* We found a suitable memory range */
 470                 break;
 471         } while (1);
 472
 473         /* If we are here, we found a suitable memory range */
 474         kbuf->mem = temp_start;
 475
 476         /* Success, stop navigating through remaining System RAM ranges */
 477         return 1;
 478 }
 479
 480 static int locate_mem_hole_bottom_up(unsigned long start, unsigned long end,
 481                                      struct kexec_buf *kbuf)
 482 {
 483         struct kimage *image = kbuf->image;
 484         unsigned long temp_start, temp_end;
 485
 486         temp_start = max(start, kbuf->buf_min);
 487
 488         do {
 489                 temp_start = ALIGN(temp_start, kbuf->buf_align);
 490                 temp_end = temp_start + kbuf->memsz - 1;
 491
 492                 if (temp_end > end || temp_end > kbuf->buf_max)
 493                         return 0;
 494                 /*
 495                  * Make sure this does not conflict with any of existing
 496                  * segments
 497                  */
 498                 if (kimage_is_destination_range(image, temp_start, temp_end)) {
 499                         temp_start = temp_start + PAGE_SIZE;
 500                         continue;
 501                 }
 502
 503                 /* We found a suitable memory range */
 504                 break;
 505         } while (1);
 506
 507         /* If we are here, we found a suitable memory range */
 508         kbuf->mem = temp_start;
 509
 510         /* Success, stop navigating through remaining System RAM ranges */
 511         return 1;
 512 }
 513
 514 static int locate_mem_hole_callback(struct resource *res, void *arg)
 515 {
 516         struct kexec_buf *kbuf = (struct kexec_buf *)arg;
 517         u64 start = res->start, end = res->end;
 518         unsigned long sz = end - start + 1;
 519
 520         /* Returning 0 will take to next memory range */
 521
 522         /* Don't use memory that will be detected and handled by a driver. */
 523         if (res->flags & IORESOURCE_MEM_DRIVER_MANAGED)
 524                 return 0;
 525
 526         if (sz < kbuf->memsz)
 527                 return 0;
 528
 529         if (end < kbuf->buf_min || start > kbuf->buf_max)
 530                 return 0;
 531
 532         /*
 533          * Allocate memory top down with-in ram range. Otherwise bottom up
 534          * allocation.
 535          */
 536         if (kbuf->top_down)
 537                 return locate_mem_hole_top_down(start, end, kbuf);
 538         return locate_mem_hole_bottom_up(start, end, kbuf);
 539 }
 540
 541 #ifdef CONFIG_ARCH_KEEP_MEMBLOCK
 542 static int kexec_walk_memblock(struct kexec_buf *kbuf,
 543                                int (*func)(struct resource *, void *))
 544 {
 545         int ret = 0;
 546         u64 i;
 547         phys_addr_t mstart, mend;
 548         struct resource res = { };
 549
 550         if (kbuf->image->type == KEXEC_TYPE_CRASH)
 551                 return func(&crashk_res, kbuf);
 552
 553         if (kbuf->top_down) {
 554                 for_each_free_mem_range_reverse(i, NUMA_NO_NODE, MEMBLOCK_NONE,
 555                                                 &mstart, &mend, NULL) {
 556                         /*
 557                          * In memblock, end points to the first byte after the
 558                          * range while in kexec, end points to the last byte
 559                          * in the range.
 560                          */
 561                         res.start = mstart;
 562                         res.end = mend - 1;
 563                         ret = func(&res, kbuf);
 564                         if (ret)
 565                                 break;
 566                 }
 567         } else {
 568                 for_each_free_mem_range(i, NUMA_NO_NODE, MEMBLOCK_NONE,
 569                                         &mstart, &mend, NULL) {
 570                         /*
 571                          * In memblock, end points to the first byte after the
 572                          * range while in kexec, end points to the last byte
 573                          * in the range.
 574                          */
 575                         res.start = mstart;
 576                         res.end = mend - 1;
 577                         ret = func(&res, kbuf);
 578                         if (ret)
 579                                 break;
 580                 }
 581         }
 582
 583         return ret;
 584 }
 585 #else
 586 static int kexec_walk_memblock(struct kexec_buf *kbuf,
 587                                int (*func)(struct resource *, void *))
 588 {
 589         return 0;
 590 }
 591 #endif
 592
 593 /**
 594  * kexec_walk_resources - call func(data) on free memory regions
 595  * @kbuf:       Context info for the search. Also passed to @func.
 596  * @func:       Function to call for each memory region.
 597  *
 598  * Return: The memory walk will stop when func returns a non-zero value
 599  * and that value will be returned. If all free regions are visited without
 600  * func returning non-zero, then zero will be returned.
 601  */
 602 static int kexec_walk_resources(struct kexec_buf *kbuf,
 603                                 int (*func)(struct resource *, void *))
 604 {
 605         if (kbuf->image->type == KEXEC_TYPE_CRASH)
 606                 return walk_iomem_res_desc(crashk_res.desc,
 607                                            IORESOURCE_SYSTEM_RAM | IORESOURCE_BUSY,
 608                                            crashk_res.start, crashk_res.end,
 609                                            kbuf, func);
 610         else
 611                 return walk_system_ram_res(0, ULONG_MAX, kbuf, func);
 612 }
 613
 614 /**
 615  * kexec_locate_mem_hole - find free memory for the purgatory or the next kernel
 616  * @kbuf:       Parameters for the memory search.
 617  *
 618  * On success, kbuf->mem will have the start address of the memory region found.
 619  *
 620  * Return: 0 on success, negative errno on error.
 621  */
 622 int kexec_locate_mem_hole(struct kexec_buf *kbuf)
 623 {
 624         int ret;
 625
 626         /* Arch knows where to place */
 627         if (kbuf->mem != KEXEC_BUF_MEM_UNKNOWN)
 628                 return 0;
 629
 630         if (!IS_ENABLED(CONFIG_ARCH_KEEP_MEMBLOCK))
 631                 ret = kexec_walk_resources(kbuf, locate_mem_hole_callback);
 632         else
 633                 ret = kexec_walk_memblock(kbuf, locate_mem_hole_callback);
 634
 635         return ret == 1 ? 0 : -EADDRNOTAVAIL;
 636 }
 637
 638 /**
 639  * kexec_add_buffer - place a buffer in a kexec segment
 640  * @kbuf:       Buffer contents and memory parameters.
 641  *
 642  * This function assumes that kexec_mutex is held.
 643  * On successful return, @kbuf->mem will have the physical address of
 644  * the buffer in memory.
 645  *
 646  * Return: 0 on success, negative errno on error.
 647  */
 648 int kexec_add_buffer(struct kexec_buf *kbuf)
 649 {
 650
 651         struct kexec_segment *ksegment;
 652         int ret;
 653
 654         /* Currently adding segment this way is allowed only in file mode */
 655         if (!kbuf->image->file_mode)
 656                 return -EINVAL;
 657
 658         if (kbuf->image->nr_segments >= KEXEC_SEGMENT_MAX)
 659                 return -EINVAL;
 660
 661         /*
 662          * Make sure we are not trying to add buffer after allocating
 663          * control pages. All segments need to be placed first before
 664          * any control pages are allocated. As control page allocation
 665          * logic goes through list of segments to make sure there are
 666          * no destination overlaps.
 667          */
 668         if (!list_empty(&kbuf->image->control_pages)) {
 669                 WARN_ON(1);
 670                 return -EINVAL;
 671         }
 672
 673         /* Ensure minimum alignment needed for segments. */
 674         kbuf->memsz = ALIGN(kbuf->memsz, PAGE_SIZE);
 675         kbuf->buf_align = max(kbuf->buf_align, PAGE_SIZE);
 676
 677         /* Walk the RAM ranges and allocate a suitable range for the buffer */
 678         ret = kexec_locate_mem_hole(kbuf);
 679         if (ret)
 680                 return ret;
 681
 682         /* Found a suitable memory range */
 683         ksegment = &kbuf->image->segment[kbuf->image->nr_segments];
 684         ksegment->kbuf = kbuf->buffer;
 685         ksegment->bufsz = kbuf->bufsz;
 686         ksegment->mem = kbuf->mem;
 687         ksegment->memsz = kbuf->memsz;
 688         kbuf->image->nr_segments++;
 689         return 0;
 690 }
 691
 692 /* Calculate and store the digest of segments */
 693 static int kexec_calculate_store_digests(struct kimage *image)
 694 {
 695         struct crypto_shash *tfm;
 696         struct shash_desc *desc;
 697         int ret = 0, i, j, zero_buf_sz, sha_region_sz;
 698         size_t desc_size, nullsz;
 699         char *digest;
 700         void *zero_buf;
 701         struct kexec_sha_region *sha_regions;
 702         struct purgatory_info *pi = &image->purgatory_info;
 703
 704         if (!IS_ENABLED(CONFIG_ARCH_HAS_KEXEC_PURGATORY))
 705                 return 0;
 706
 707         zero_buf = __va(page_to_pfn(ZERO_PAGE(0)) << PAGE_SHIFT);
 708         zero_buf_sz = PAGE_SIZE;
 709
 710         tfm = crypto_alloc_shash("sha256", 0, 0);
 711         if (IS_ERR(tfm)) {
 712                 ret = PTR_ERR(tfm);
 713                 goto out;
 714         }
 715
 716         desc_size = crypto_shash_descsize(tfm) + sizeof(*desc);
 717         desc = kzalloc(desc_size, GFP_KERNEL);
 718         if (!desc) {
 719                 ret = -ENOMEM;
 720                 goto out_free_tfm;
 721         }
 722
 723         sha_region_sz = KEXEC_SEGMENT_MAX * sizeof(struct kexec_sha_region);
 724         sha_regions = vzalloc(sha_region_sz);
 725         if (!sha_regions)
 726                 goto out_free_desc;
 727
 728         desc->tfm   = tfm;
 729
 730         ret = crypto_shash_init(desc);
 731         if (ret < 0)
 732                 goto out_free_sha_regions;
 733
 734         digest = kzalloc(SHA256_DIGEST_SIZE, GFP_KERNEL);
 735         if (!digest) {
 736                 ret = -ENOMEM;
 737                 goto out_free_sha_regions;
 738         }
 739
 740         for (j = i = 0; i < image->nr_segments; i++) {
 741                 struct kexec_segment *ksegment;
 742
 743                 ksegment = &image->segment[i];
 744                 /*
 745                  * Skip purgatory as it will be modified once we put digest
 746                  * info in purgatory.
 747                  */
 748                 if (ksegment->kbuf == pi->purgatory_buf)
 749                         continue;
 750
 751                 ret = crypto_shash_update(desc, ksegment->kbuf,
 752                                           ksegment->bufsz);
 753                 if (ret)
 754                         break;
 755
 756                 /*
 757                  * Assume rest of the buffer is filled with zero and
 758                  * update digest accordingly.
 759                  */
 760                 nullsz = ksegment->memsz - ksegment->bufsz;
 761                 while (nullsz) {
 762                         unsigned long bytes = nullsz;
 763
 764                         if (bytes > zero_buf_sz)
 765                                 bytes = zero_buf_sz;
 766                         ret = crypto_shash_update(desc, zero_buf, bytes);
 767                         if (ret)
 768                                 break;
 769                         nullsz -= bytes;
 770                 }
 771
 772                 if (ret)
 773                         break;
 774
 775                 sha_regions[j].start = ksegment->mem;
 776                 sha_regions[j].len = ksegment->memsz;
 777                 j++;
 778         }
 779
 780         if (!ret) {
 781                 ret = crypto_shash_final(desc, digest);
 782                 if (ret)
 783                         goto out_free_digest;
 784                 ret = kexec_purgatory_get_set_symbol(image, "purgatory_sha_regions",
 785                                                      sha_regions, sha_region_sz, 0);
 786                 if (ret)
 787                         goto out_free_digest;
 788
 789                 ret = kexec_purgatory_get_set_symbol(image, "purgatory_sha256_digest",
 790                                                      digest, SHA256_DIGEST_SIZE, 0);
 791                 if (ret)
 792                         goto out_free_digest;
 793         }
 794
 795 out_free_digest:
 796         kfree(digest);
 797 out_free_sha_regions:
 798         vfree(sha_regions);
 799 out_free_desc:
 800         kfree(desc);
 801 out_free_tfm:
 802         kfree(tfm);
 803 out:
 804         return ret;
 805 }
 806
 807 #ifdef CONFIG_ARCH_HAS_KEXEC_PURGATORY
 808 /*
 809  * kexec_purgatory_setup_kbuf - prepare buffer to load purgatory.
 810  * @pi:         Purgatory to be loaded.
 811  * @kbuf:       Buffer to setup.
 812  *
 813  * Allocates the memory needed for the buffer. Caller is responsible to free
 814  * the memory after use.
 815  *
 816  * Return: 0 on success, negative errno on error.
 817  */
 818 static int kexec_purgatory_setup_kbuf(struct purgatory_info *pi,
 819                                       struct kexec_buf *kbuf)
 820 {
 821         const Elf_Shdr *sechdrs;
 822         unsigned long bss_align;
 823         unsigned long bss_sz;
 824         unsigned long align;
 825         int i, ret;
 826
 827         sechdrs = (void *)pi->ehdr + pi->ehdr->e_shoff;
 828         kbuf->buf_align = bss_align = 1;
 829         kbuf->bufsz = bss_sz = 0;
 830
 831         for (i = 0; i < pi->ehdr->e_shnum; i++) {
 832                 if (!(sechdrs[i].sh_flags & SHF_ALLOC))
 833                         continue;
 834
 835                 align = sechdrs[i].sh_addralign;
 836                 if (sechdrs[i].sh_type != SHT_NOBITS) {
 837                         if (kbuf->buf_align < align)
 838                                 kbuf->buf_align = align;
 839                         kbuf->bufsz = ALIGN(kbuf->bufsz, align);
 840                         kbuf->bufsz += sechdrs[i].sh_size;
 841                 } else {
 842                         if (bss_align < align)
 843                                 bss_align = align;
 844                         bss_sz = ALIGN(bss_sz, align);
 845                         bss_sz += sechdrs[i].sh_size;
 846                 }
 847         }
 848         kbuf->bufsz = ALIGN(kbuf->bufsz, bss_align);
 849         kbuf->memsz = kbuf->bufsz + bss_sz;
 850         if (kbuf->buf_align < bss_align)
 851                 kbuf->buf_align = bss_align;
 852
 853         kbuf->buffer = vzalloc(kbuf->bufsz);
 854         if (!kbuf->buffer)
 855                 return -ENOMEM;
 856         pi->purgatory_buf = kbuf->buffer;
 857
 858         ret = kexec_add_buffer(kbuf);
 859         if (ret)
 860                 goto out;
 861
 862         return 0;
 863 out:
 864         vfree(pi->purgatory_buf);
 865         pi->purgatory_buf = NULL;
 866         return ret;
 867 }
 868
 869 /*
 870  * kexec_purgatory_setup_sechdrs - prepares the pi->sechdrs buffer.
 871  * @pi:         Purgatory to be loaded.
 872  * @kbuf:       Buffer prepared to store purgatory.
 873  *
 874  * Allocates the memory needed for the buffer. Caller is responsible to free
 875  * the memory after use.
 876  *
 877  * Return: 0 on success, negative errno on error.
 878  */
 879 static int kexec_purgatory_setup_sechdrs(struct purgatory_info *pi,
 880                                          struct kexec_buf *kbuf)
 881 {
 882         unsigned long bss_addr;
 883         unsigned long offset;
 884         Elf_Shdr *sechdrs;
 885         int i;
 886
 887         /*
 888          * The section headers in kexec_purgatory are read-only. In order to
 889          * have them modifiable make a temporary copy.
 890          */
 891         sechdrs = vzalloc(array_size(sizeof(Elf_Shdr), pi->ehdr->e_shnum));
 892         if (!sechdrs)
 893                 return -ENOMEM;
 894         memcpy(sechdrs, (void *)pi->ehdr + pi->ehdr->e_shoff,
 895                pi->ehdr->e_shnum * sizeof(Elf_Shdr));
 896         pi->sechdrs = sechdrs;
 897
 898         offset = 0;
 899         bss_addr = kbuf->mem + kbuf->bufsz;
 900         kbuf->image->start = pi->ehdr->e_entry;
 901
 902         for (i = 0; i < pi->ehdr->e_shnum; i++) {
 903                 unsigned long align;
 904                 void *src, *dst;
 905
 906                 if (!(sechdrs[i].sh_flags & SHF_ALLOC))
 907                         continue;
 908
 909                 align = sechdrs[i].sh_addralign;
 910                 if (sechdrs[i].sh_type == SHT_NOBITS) {
 911                         bss_addr = ALIGN(bss_addr, align);
 912                         sechdrs[i].sh_addr = bss_addr;
 913                         bss_addr += sechdrs[i].sh_size;
 914                         continue;
 915                 }
 916
 917                 offset = ALIGN(offset, align);
 918                 if (sechdrs[i].sh_flags & SHF_EXECINSTR &&
 919                     pi->ehdr->e_entry >= sechdrs[i].sh_addr &&
 920                     pi->ehdr->e_entry < (sechdrs[i].sh_addr
 921                                          + sechdrs[i].sh_size)) {
 922                         kbuf->image->start -= sechdrs[i].sh_addr;
 923                         kbuf->image->start += kbuf->mem + offset;
 924                 }
 925
 926                 src = (void *)pi->ehdr + sechdrs[i].sh_offset;
 927                 dst = pi->purgatory_buf + offset;
 928                 memcpy(dst, src, sechdrs[i].sh_size);
 929
 930                 sechdrs[i].sh_addr = kbuf->mem + offset;
 931                 sechdrs[i].sh_offset = offset;
 932                 offset += sechdrs[i].sh_size;
 933         }
 934
 935         return 0;
 936 }
 937
 938 static int kexec_apply_relocations(struct kimage *image)
 939 {
 940         int i, ret;
 941         struct purgatory_info *pi = &image->purgatory_info;
 942         const Elf_Shdr *sechdrs;
 943
 944         sechdrs = (void *)pi->ehdr + pi->ehdr->e_shoff;
 945
 946         for (i = 0; i < pi->ehdr->e_shnum; i++) {
 947                 const Elf_Shdr *relsec;
 948                 const Elf_Shdr *symtab;
 949                 Elf_Shdr *section;
 950
 951                 relsec = sechdrs + i;
 952
 953                 if (relsec->sh_type != SHT_RELA &&
 954                     relsec->sh_type != SHT_REL)
 955                         continue;
 956
 957                 /*
 958                  * For section of type SHT_RELA/SHT_REL,
 959                  * ->sh_link contains section header index of associated
 960                  * symbol table. And ->sh_info contains section header
 961                  * index of section to which relocations apply.
 962                  */
 963                 if (relsec->sh_info >= pi->ehdr->e_shnum ||
 964                     relsec->sh_link >= pi->ehdr->e_shnum)
 965                         return -ENOEXEC;
 966
 967                 section = pi->sechdrs + relsec->sh_info;
 968                 symtab = sechdrs + relsec->sh_link;
 969
 970                 if (!(section->sh_flags & SHF_ALLOC))
 971                         continue;
 972
 973                 /*
 974                  * symtab->sh_link contain section header index of associated
 975                  * string table.
 976                  */
 977                 if (symtab->sh_link >= pi->ehdr->e_shnum)
 978                         /* Invalid section number? */
 979                         continue;
 980
 981                 /*
 982                  * Respective architecture needs to provide support for applying
 983                  * relocations of type SHT_RELA/SHT_REL.
 984                  */
 985                 if (relsec->sh_type == SHT_RELA)
 986                         ret = arch_kexec_apply_relocations_add(pi, section,
 987                                                                relsec, symtab);
 988                 else if (relsec->sh_type == SHT_REL)
 989                         ret = arch_kexec_apply_relocations(pi, section,
 990                                                            relsec, symtab);
 991                 if (ret)
 992                         return ret;
 993         }
 994
 995         return 0;
 996 }
 997
 998 /*
 999  * kexec_load_purgatory - Load and relocate the purgatory object.
1000  * @image:      Image to add the purgatory to.
1001  * @kbuf:       Memory parameters to use.
1002  *
1003  * Allocates the memory needed for image->purgatory_info.sechdrs and
1004  * image->purgatory_info.purgatory_buf/kbuf->buffer. Caller is responsible
1005  * to free the memory after use.
1006  *
1007  * Return: 0 on success, negative errno on error.
1008  */
1009 int kexec_load_purgatory(struct kimage *image, struct kexec_buf *kbuf)
1010 {
1011         struct purgatory_info *pi = &image->purgatory_info;
1012         int ret;
1013
1014         if (kexec_purgatory_size <= 0)
1015                 return -EINVAL;
1016
1017         pi->ehdr = (const Elf_Ehdr *)kexec_purgatory;
1018
1019         ret = kexec_purgatory_setup_kbuf(pi, kbuf);
1020         if (ret)
1021                 return ret;
1022
1023         ret = kexec_purgatory_setup_sechdrs(pi, kbuf);
1024         if (ret)
1025                 goto out_free_kbuf;
1026
1027         ret = kexec_apply_relocations(image);
1028         if (ret)
1029                 goto out;
1030
1031         return 0;
1032 out:
1033         vfree(pi->sechdrs);
1034         pi->sechdrs = NULL;
1035 out_free_kbuf:
1036         vfree(pi->purgatory_buf);
1037         pi->purgatory_buf = NULL;
1038         return ret;
1039 }
1040
1041 /*
1042  * kexec_purgatory_find_symbol - find a symbol in the purgatory
1043  * @pi:         Purgatory to search in.
1044  * @name:       Name of the symbol.
1045  *
1046  * Return: pointer to symbol in read-only symtab on success, NULL on error.
1047  */
1048 static const Elf_Sym *kexec_purgatory_find_symbol(struct purgatory_info *pi,
1049                                                   const char *name)
1050 {
1051         const Elf_Shdr *sechdrs;
1052         const Elf_Ehdr *ehdr;
1053         const Elf_Sym *syms;
1054         const char *strtab;
1055         int i, k;
1056
1057         if (!pi->ehdr)
1058                 return NULL;
1059
1060         ehdr = pi->ehdr;
1061         sechdrs = (void *)ehdr + ehdr->e_shoff;
1062
1063         for (i = 0; i < ehdr->e_shnum; i++) {
1064                 if (sechdrs[i].sh_type != SHT_SYMTAB)
1065                         continue;
1066
1067                 if (sechdrs[i].sh_link >= ehdr->e_shnum)
1068                         /* Invalid strtab section number */
1069                         continue;
1070                 strtab = (void *)ehdr + sechdrs[sechdrs[i].sh_link].sh_offset;
1071                 syms = (void *)ehdr + sechdrs[i].sh_offset;
1072
1073                 /* Go through symbols for a match */
1074                 for (k = 0; k < sechdrs[i].sh_size/sizeof(Elf_Sym); k++) {
1075                         if (ELF_ST_BIND(syms[k].st_info) != STB_GLOBAL)
1076                                 continue;
1077
1078                         if (strcmp(strtab + syms[k].st_name, name) != 0)
1079                                 continue;
1080
1081                         if (syms[k].st_shndx == SHN_UNDEF ||
1082                             syms[k].st_shndx >= ehdr->e_shnum) {
1083                                 pr_debug("Symbol: %s has bad section index %d.\n",
1084                                                 name, syms[k].st_shndx);
1085                                 return NULL;
1086                         }
1087
1088                         /* Found the symbol we are looking for */
1089                         return &syms[k];
1090                 }
1091         }
1092
1093         return NULL;
1094 }
1095
1096 void *kexec_purgatory_get_symbol_addr(struct kimage *image, const char *name)
1097 {
1098         struct purgatory_info *pi = &image->purgatory_info;
1099         const Elf_Sym *sym;
1100         Elf_Shdr *sechdr;
1101
1102         sym = kexec_purgatory_find_symbol(pi, name);
1103         if (!sym)
1104                 return ERR_PTR(-EINVAL);
1105
1106         sechdr = &pi->sechdrs[sym->st_shndx];
1107
1108         /*
1109          * Returns the address where symbol will finally be loaded after
1110          * kexec_load_segment()
1111          */
1112         return (void *)(sechdr->sh_addr + sym->st_value);
1113 }
1114
1115 /*
1116  * Get or set value of a symbol. If "get_value" is true, symbol value is
1117  * returned in buf otherwise symbol value is set based on value in buf.
1118  */
1119 int kexec_purgatory_get_set_symbol(struct kimage *image, const char *name,
1120                                    void *buf, unsigned int size, bool get_value)
1121 {
1122         struct purgatory_info *pi = &image->purgatory_info;
1123         const Elf_Sym *sym;
1124         Elf_Shdr *sec;
1125         char *sym_buf;
1126
1127         sym = kexec_purgatory_find_symbol(pi, name);
1128         if (!sym)
1129                 return -EINVAL;
1130
1131         if (sym->st_size != size) {
1132                 pr_err("symbol %s size mismatch: expected %lu actual %u\n",
1133                        name, (unsigned long)sym->st_size, size);
1134                 return -EINVAL;
1135         }
1136
1137         sec = pi->sechdrs + sym->st_shndx;
1138
1139         if (sec->sh_type == SHT_NOBITS) {
1140                 pr_err("symbol %s is in a bss section. Cannot %s\n", name,
1141                        get_value ? "get" : "set");
1142                 return -EINVAL;
1143         }
1144
1145         sym_buf = (char *)pi->purgatory_buf + sec->sh_offset + sym->st_value;
1146
1147         if (get_value)
1148                 memcpy((void *)buf, sym_buf, size);
1149         else
1150                 memcpy((void *)sym_buf, buf, size);
1151
1152         return 0;
1153 }
1154 #endif /* CONFIG_ARCH_HAS_KEXEC_PURGATORY */
1155
1156 int crash_exclude_mem_range(struct crash_mem *mem,
1157                             unsigned long long mstart, unsigned long long mend)
1158 {
1159         int i, j;
1160         unsigned long long start, end;
1161         struct crash_mem_range temp_range = {0, 0};
1162
1163         for (i = 0; i < mem->nr_ranges; i++) {
1164                 start = mem->ranges[i].start;
1165                 end = mem->ranges[i].end;
1166
1167                 if (mstart > end || mend < start)
1168                         continue;
1169
1170                 /* Truncate any area outside of range */
1171                 if (mstart < start)
1172                         mstart = start;
1173                 if (mend > end)
1174                         mend = end;
1175
1176                 /* Found completely overlapping range */
1177                 if (mstart == start && mend == end) {
1178                         mem->ranges[i].start = 0;
1179                         mem->ranges[i].end = 0;
1180                         if (i < mem->nr_ranges - 1) {
1181                                 /* Shift rest of the ranges to left */
1182                                 for (j = i; j < mem->nr_ranges - 1; j++) {
1183                                         mem->ranges[j].start =
1184                                                 mem->ranges[j+1].start;
1185                                         mem->ranges[j].end =
1186                                                         mem->ranges[j+1].end;
1187                                 }
1188                         }
1189                         mem->nr_ranges--;
1190                         return 0;
1191                 }
1192
1193                 if (mstart > start && mend < end) {
1194                         /* Split original range */
1195                         mem->ranges[i].end = mstart - 1;
1196                         temp_range.start = mend + 1;
1197                         temp_range.end = end;
1198                 } else if (mstart != start)
1199                         mem->ranges[i].end = mstart - 1;
1200                 else
1201                         mem->ranges[i].start = mend + 1;
1202                 break;
1203         }
1204
1205         /* If a split happened, add the split to array */
1206         if (!temp_range.end)
1207                 return 0;
1208
1209         /* Split happened */
1210         if (i == mem->max_nr_ranges - 1)
1211                 return -ENOMEM;
1212
1213         /* Location where new range should go */
1214         j = i + 1;
1215         if (j < mem->nr_ranges) {
1216                 /* Move over all ranges one slot towards the end */
1217                 for (i = mem->nr_ranges - 1; i >= j; i--)
1218                         mem->ranges[i + 1] = mem->ranges[i];
1219         }
1220
1221         mem->ranges[j].start = temp_range.start;
1222         mem->ranges[j].end = temp_range.end;
1223         mem->nr_ranges++;
1224         return 0;
1225 }
1226
1227 int crash_prepare_elf64_headers(struct crash_mem *mem, int kernel_map,
1228                           void **addr, unsigned long *sz)
1229 {
1230         Elf64_Ehdr *ehdr;
1231         Elf64_Phdr *phdr;
1232         unsigned long nr_cpus = num_possible_cpus(), nr_phdr, elf_sz;
1233         unsigned char *buf;
1234         unsigned int cpu, i;
1235         unsigned long long notes_addr;
1236         unsigned long mstart, mend;
1237
1238         /* extra phdr for vmcoreinfo elf note */
1239         nr_phdr = nr_cpus + 1;
1240         nr_phdr += mem->nr_ranges;
1241
1242         /*
1243          * kexec-tools creates an extra PT_LOAD phdr for kernel text mapping
1244          * area (for example, ffffffff80000000 - ffffffffa0000000 on x86_64).
1245          * I think this is required by tools like gdb. So same physical
1246          * memory will be mapped in two elf headers. One will contain kernel
1247          * text virtual addresses and other will have __va(physical) addresses.
1248          */
1249
1250         nr_phdr++;
1251         elf_sz = sizeof(Elf64_Ehdr) + nr_phdr * sizeof(Elf64_Phdr);
1252         elf_sz = ALIGN(elf_sz, ELF_CORE_HEADER_ALIGN);
1253
1254         buf = vzalloc(elf_sz);
1255         if (!buf)
1256                 return -ENOMEM;
1257
1258         ehdr = (Elf64_Ehdr *)buf;
1259         phdr = (Elf64_Phdr *)(ehdr + 1);
1260         memcpy(ehdr->e_ident, ELFMAG, SELFMAG);
1261         ehdr->e_ident[EI_CLASS] = ELFCLASS64;
1262         ehdr->e_ident[EI_DATA] = ELFDATA2LSB;
1263         ehdr->e_ident[EI_VERSION] = EV_CURRENT;
1264         ehdr->e_ident[EI_OSABI] = ELF_OSABI;
1265         memset(ehdr->e_ident + EI_PAD, 0, EI_NIDENT - EI_PAD);
1266         ehdr->e_type = ET_CORE;
1267         ehdr->e_machine = ELF_ARCH;
1268         ehdr->e_version = EV_CURRENT;
1269         ehdr->e_phoff = sizeof(Elf64_Ehdr);
1270         ehdr->e_ehsize = sizeof(Elf64_Ehdr);
1271         ehdr->e_phentsize = sizeof(Elf64_Phdr);
1272
1273         /* Prepare one phdr of type PT_NOTE for each present cpu */
1274         for_each_present_cpu(cpu) {
1275                 phdr->p_type = PT_NOTE;
1276                 notes_addr = per_cpu_ptr_to_phys(per_cpu_ptr(crash_notes, cpu));
1277                 phdr->p_offset = phdr->p_paddr = notes_addr;
1278                 phdr->p_filesz = phdr->p_memsz = sizeof(note_buf_t);
1279                 (ehdr->e_phnum)++;
1280                 phdr++;
1281         }
1282
1283         /* Prepare one PT_NOTE header for vmcoreinfo */
1284         phdr->p_type = PT_NOTE;
1285         phdr->p_offset = phdr->p_paddr = paddr_vmcoreinfo_note();
1286         phdr->p_filesz = phdr->p_memsz = VMCOREINFO_NOTE_SIZE;
1287         (ehdr->e_phnum)++;
1288         phdr++;
1289
1290         /* Prepare PT_LOAD type program header for kernel text region */
1291         if (kernel_map) {
1292                 phdr->p_type = PT_LOAD;
1293                 phdr->p_flags = PF_R|PF_W|PF_X;
1294                 phdr->p_vaddr = (unsigned long) _text;
1295                 phdr->p_filesz = phdr->p_memsz = _end - _text;
1296                 phdr->p_offset = phdr->p_paddr = __pa_symbol(_text);
1297                 ehdr->e_phnum++;
1298                 phdr++;
1299         }
1300
1301         /* Go through all the ranges in mem->ranges[] and prepare phdr */
1302         for (i = 0; i < mem->nr_ranges; i++) {
1303                 mstart = mem->ranges[i].start;
1304                 mend = mem->ranges[i].end;
1305
1306                 phdr->p_type = PT_LOAD;
1307                 phdr->p_flags = PF_R|PF_W|PF_X;
1308                 phdr->p_offset  = mstart;
1309
1310                 phdr->p_paddr = mstart;
1311                 phdr->p_vaddr = (unsigned long) __va(mstart);
1312                 phdr->p_filesz = phdr->p_memsz = mend - mstart + 1;
1313                 phdr->p_align = 0;
1314                 ehdr->e_phnum++;
1315                 phdr++;
1316                 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",
1317                         phdr, phdr->p_vaddr, phdr->p_paddr, phdr->p_filesz,
1318                         ehdr->e_phnum, phdr->p_offset);
1319         }
1320
1321         *addr = buf;
1322         *sz = elf_sz;
1323         return 0;
1324 }