2 * kexec: kexec_file_load system call
4 * Copyright (C) 2014 Red Hat Inc.
6 * Vivek Goyal <vgoyal@redhat.com>
8 * This source code is licensed under the GNU General Public License,
9 * Version 2. See the file COPYING for more details.
12 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
14 #include <linux/capability.h>
16 #include <linux/file.h>
17 #include <linux/slab.h>
18 #include <linux/kexec.h>
19 #include <linux/mutex.h>
20 #include <linux/list.h>
21 #include <crypto/hash.h>
22 #include <crypto/sha.h>
23 #include <linux/syscalls.h>
24 #include <linux/vmalloc.h>
25 #include "kexec_internal.h"
28 * Declare these symbols weak so that if architecture provides a purgatory,
29 * these will be overridden.
31 char __weak kexec_purgatory[0];
32 size_t __weak kexec_purgatory_size = 0;
34 static int kexec_calculate_store_digests(struct kimage *image);
36 static int copy_file_from_fd(int fd, void **buf, unsigned long *buf_len)
38 struct fd f = fdget(fd);
47 ret = vfs_getattr(&f.file->f_path, &stat);
51 if (stat.size > INT_MAX) {
56 /* Don't hand 0 to vmalloc, it whines. */
62 *buf = vmalloc(stat.size);
69 while (pos < stat.size) {
70 bytes = kernel_read(f.file, pos, (char *)(*buf) + pos,
83 if (pos != stat.size) {
95 /* Architectures can provide this probe function */
96 int __weak arch_kexec_kernel_image_probe(struct kimage *image, void *buf,
97 unsigned long buf_len)
102 void * __weak arch_kexec_kernel_image_load(struct kimage *image)
104 return ERR_PTR(-ENOEXEC);
107 int __weak arch_kimage_file_post_load_cleanup(struct kimage *image)
112 #ifdef CONFIG_KEXEC_VERIFY_SIG
113 int __weak arch_kexec_kernel_verify_sig(struct kimage *image, void *buf,
114 unsigned long buf_len)
116 return -EKEYREJECTED;
120 /* Apply relocations of type RELA */
122 arch_kexec_apply_relocations_add(const Elf_Ehdr *ehdr, Elf_Shdr *sechdrs,
125 pr_err("RELA relocation unsupported.\n");
129 /* Apply relocations of type REL */
131 arch_kexec_apply_relocations(const Elf_Ehdr *ehdr, Elf_Shdr *sechdrs,
134 pr_err("REL relocation unsupported.\n");
139 * Free up memory used by kernel, initrd, and command line. This is temporary
140 * memory allocation which is not needed any more after these buffers have
141 * been loaded into separate segments and have been copied elsewhere.
143 void kimage_file_post_load_cleanup(struct kimage *image)
145 struct purgatory_info *pi = &image->purgatory_info;
147 vfree(image->kernel_buf);
148 image->kernel_buf = NULL;
150 vfree(image->initrd_buf);
151 image->initrd_buf = NULL;
153 kfree(image->cmdline_buf);
154 image->cmdline_buf = NULL;
156 vfree(pi->purgatory_buf);
157 pi->purgatory_buf = NULL;
162 /* See if architecture has anything to cleanup post load */
163 arch_kimage_file_post_load_cleanup(image);
166 * Above call should have called into bootloader to free up
167 * any data stored in kimage->image_loader_data. It should
168 * be ok now to free it up.
170 kfree(image->image_loader_data);
171 image->image_loader_data = NULL;
175 * In file mode list of segments is prepared by kernel. Copy relevant
176 * data from user space, do error checking, prepare segment list
179 kimage_file_prepare_segments(struct kimage *image, int kernel_fd, int initrd_fd,
180 const char __user *cmdline_ptr,
181 unsigned long cmdline_len, unsigned flags)
186 ret = copy_file_from_fd(kernel_fd, &image->kernel_buf,
187 &image->kernel_buf_len);
191 /* Call arch image probe handlers */
192 ret = arch_kexec_kernel_image_probe(image, image->kernel_buf,
193 image->kernel_buf_len);
198 #ifdef CONFIG_KEXEC_VERIFY_SIG
199 ret = arch_kexec_kernel_verify_sig(image, image->kernel_buf,
200 image->kernel_buf_len);
202 pr_debug("kernel signature verification failed.\n");
205 pr_debug("kernel signature verification successful.\n");
207 /* It is possible that there no initramfs is being loaded */
208 if (!(flags & KEXEC_FILE_NO_INITRAMFS)) {
209 ret = copy_file_from_fd(initrd_fd, &image->initrd_buf,
210 &image->initrd_buf_len);
216 image->cmdline_buf = kzalloc(cmdline_len, GFP_KERNEL);
217 if (!image->cmdline_buf) {
222 ret = copy_from_user(image->cmdline_buf, cmdline_ptr,
229 image->cmdline_buf_len = cmdline_len;
231 /* command line should be a string with last byte null */
232 if (image->cmdline_buf[cmdline_len - 1] != '\0') {
238 /* Call arch image load handlers */
239 ldata = arch_kexec_kernel_image_load(image);
242 ret = PTR_ERR(ldata);
246 image->image_loader_data = ldata;
248 /* In case of error, free up all allocated memory in this function */
250 kimage_file_post_load_cleanup(image);
255 kimage_file_alloc_init(struct kimage **rimage, int kernel_fd,
256 int initrd_fd, const char __user *cmdline_ptr,
257 unsigned long cmdline_len, unsigned long flags)
260 struct kimage *image;
261 bool kexec_on_panic = flags & KEXEC_FILE_ON_CRASH;
263 image = do_kimage_alloc_init();
267 image->file_mode = 1;
269 if (kexec_on_panic) {
270 /* Enable special crash kernel control page alloc policy. */
271 image->control_page = crashk_res.start;
272 image->type = KEXEC_TYPE_CRASH;
275 ret = kimage_file_prepare_segments(image, kernel_fd, initrd_fd,
276 cmdline_ptr, cmdline_len, flags);
280 ret = sanity_check_segment_list(image);
282 goto out_free_post_load_bufs;
285 image->control_code_page = kimage_alloc_control_pages(image,
286 get_order(KEXEC_CONTROL_PAGE_SIZE));
287 if (!image->control_code_page) {
288 pr_err("Could not allocate control_code_buffer\n");
289 goto out_free_post_load_bufs;
292 if (!kexec_on_panic) {
293 image->swap_page = kimage_alloc_control_pages(image, 0);
294 if (!image->swap_page) {
295 pr_err("Could not allocate swap buffer\n");
296 goto out_free_control_pages;
302 out_free_control_pages:
303 kimage_free_page_list(&image->control_pages);
304 out_free_post_load_bufs:
305 kimage_file_post_load_cleanup(image);
311 SYSCALL_DEFINE5(kexec_file_load, int, kernel_fd, int, initrd_fd,
312 unsigned long, cmdline_len, const char __user *, cmdline_ptr,
313 unsigned long, flags)
316 struct kimage **dest_image, *image;
318 /* We only trust the superuser with rebooting the system. */
319 if (!capable(CAP_SYS_BOOT) || kexec_load_disabled)
322 /* Make sure we have a legal set of flags */
323 if (flags != (flags & KEXEC_FILE_FLAGS))
328 if (!mutex_trylock(&kexec_mutex))
331 dest_image = &kexec_image;
332 if (flags & KEXEC_FILE_ON_CRASH) {
333 dest_image = &kexec_crash_image;
334 if (kexec_crash_image)
335 arch_kexec_unprotect_crashkres();
338 if (flags & KEXEC_FILE_UNLOAD)
342 * In case of crash, new kernel gets loaded in reserved region. It is
343 * same memory where old crash kernel might be loaded. Free any
344 * current crash dump kernel before we corrupt it.
346 if (flags & KEXEC_FILE_ON_CRASH)
347 kimage_free(xchg(&kexec_crash_image, NULL));
349 ret = kimage_file_alloc_init(&image, kernel_fd, initrd_fd, cmdline_ptr,
354 ret = machine_kexec_prepare(image);
358 ret = kexec_calculate_store_digests(image);
362 for (i = 0; i < image->nr_segments; i++) {
363 struct kexec_segment *ksegment;
365 ksegment = &image->segment[i];
366 pr_debug("Loading segment %d: buf=0x%p bufsz=0x%zx mem=0x%lx memsz=0x%zx\n",
367 i, ksegment->buf, ksegment->bufsz, ksegment->mem,
370 ret = kimage_load_segment(image, &image->segment[i]);
375 kimage_terminate(image);
378 * Free up any temporary buffers allocated which are not needed
379 * after image has been loaded
381 kimage_file_post_load_cleanup(image);
383 image = xchg(dest_image, image);
385 if ((flags & KEXEC_FILE_ON_CRASH) && kexec_crash_image)
386 arch_kexec_protect_crashkres();
388 mutex_unlock(&kexec_mutex);
393 static int locate_mem_hole_top_down(unsigned long start, unsigned long end,
394 struct kexec_buf *kbuf)
396 struct kimage *image = kbuf->image;
397 unsigned long temp_start, temp_end;
399 temp_end = min(end, kbuf->buf_max);
400 temp_start = temp_end - kbuf->memsz;
403 /* align down start */
404 temp_start = temp_start & (~(kbuf->buf_align - 1));
406 if (temp_start < start || temp_start < kbuf->buf_min)
409 temp_end = temp_start + kbuf->memsz - 1;
412 * Make sure this does not conflict with any of existing
415 if (kimage_is_destination_range(image, temp_start, temp_end)) {
416 temp_start = temp_start - PAGE_SIZE;
420 /* We found a suitable memory range */
424 /* If we are here, we found a suitable memory range */
425 kbuf->mem = temp_start;
427 /* Success, stop navigating through remaining System RAM ranges */
431 static int locate_mem_hole_bottom_up(unsigned long start, unsigned long end,
432 struct kexec_buf *kbuf)
434 struct kimage *image = kbuf->image;
435 unsigned long temp_start, temp_end;
437 temp_start = max(start, kbuf->buf_min);
440 temp_start = ALIGN(temp_start, kbuf->buf_align);
441 temp_end = temp_start + kbuf->memsz - 1;
443 if (temp_end > end || temp_end > kbuf->buf_max)
446 * Make sure this does not conflict with any of existing
449 if (kimage_is_destination_range(image, temp_start, temp_end)) {
450 temp_start = temp_start + PAGE_SIZE;
454 /* We found a suitable memory range */
458 /* If we are here, we found a suitable memory range */
459 kbuf->mem = temp_start;
461 /* Success, stop navigating through remaining System RAM ranges */
465 static int locate_mem_hole_callback(u64 start, u64 end, void *arg)
467 struct kexec_buf *kbuf = (struct kexec_buf *)arg;
468 unsigned long sz = end - start + 1;
470 /* Returning 0 will take to next memory range */
471 if (sz < kbuf->memsz)
474 if (end < kbuf->buf_min || start > kbuf->buf_max)
478 * Allocate memory top down with-in ram range. Otherwise bottom up
482 return locate_mem_hole_top_down(start, end, kbuf);
483 return locate_mem_hole_bottom_up(start, end, kbuf);
487 * Helper function for placing a buffer in a kexec segment. This assumes
488 * that kexec_mutex is held.
490 int kexec_add_buffer(struct kimage *image, char *buffer, unsigned long bufsz,
491 unsigned long memsz, unsigned long buf_align,
492 unsigned long buf_min, unsigned long buf_max,
493 bool top_down, unsigned long *load_addr)
496 struct kexec_segment *ksegment;
497 struct kexec_buf buf, *kbuf;
500 /* Currently adding segment this way is allowed only in file mode */
501 if (!image->file_mode)
504 if (image->nr_segments >= KEXEC_SEGMENT_MAX)
508 * Make sure we are not trying to add buffer after allocating
509 * control pages. All segments need to be placed first before
510 * any control pages are allocated. As control page allocation
511 * logic goes through list of segments to make sure there are
512 * no destination overlaps.
514 if (!list_empty(&image->control_pages)) {
519 memset(&buf, 0, sizeof(struct kexec_buf));
522 kbuf->buffer = buffer;
525 kbuf->memsz = ALIGN(memsz, PAGE_SIZE);
526 kbuf->buf_align = max(buf_align, PAGE_SIZE);
527 kbuf->buf_min = buf_min;
528 kbuf->buf_max = buf_max;
529 kbuf->top_down = top_down;
531 /* Walk the RAM ranges and allocate a suitable range for the buffer */
532 if (image->type == KEXEC_TYPE_CRASH)
533 ret = walk_iomem_res_desc(crashk_res.desc,
534 IORESOURCE_SYSTEM_RAM | IORESOURCE_BUSY,
535 crashk_res.start, crashk_res.end, kbuf,
536 locate_mem_hole_callback);
538 ret = walk_system_ram_res(0, -1, kbuf,
539 locate_mem_hole_callback);
541 /* A suitable memory range could not be found for buffer */
542 return -EADDRNOTAVAIL;
545 /* Found a suitable memory range */
546 ksegment = &image->segment[image->nr_segments];
547 ksegment->kbuf = kbuf->buffer;
548 ksegment->bufsz = kbuf->bufsz;
549 ksegment->mem = kbuf->mem;
550 ksegment->memsz = kbuf->memsz;
551 image->nr_segments++;
552 *load_addr = ksegment->mem;
556 /* Calculate and store the digest of segments */
557 static int kexec_calculate_store_digests(struct kimage *image)
559 struct crypto_shash *tfm;
560 struct shash_desc *desc;
561 int ret = 0, i, j, zero_buf_sz, sha_region_sz;
562 size_t desc_size, nullsz;
565 struct kexec_sha_region *sha_regions;
566 struct purgatory_info *pi = &image->purgatory_info;
568 zero_buf = __va(page_to_pfn(ZERO_PAGE(0)) << PAGE_SHIFT);
569 zero_buf_sz = PAGE_SIZE;
571 tfm = crypto_alloc_shash("sha256", 0, 0);
577 desc_size = crypto_shash_descsize(tfm) + sizeof(*desc);
578 desc = kzalloc(desc_size, GFP_KERNEL);
584 sha_region_sz = KEXEC_SEGMENT_MAX * sizeof(struct kexec_sha_region);
585 sha_regions = vzalloc(sha_region_sz);
592 ret = crypto_shash_init(desc);
594 goto out_free_sha_regions;
596 digest = kzalloc(SHA256_DIGEST_SIZE, GFP_KERNEL);
599 goto out_free_sha_regions;
602 for (j = i = 0; i < image->nr_segments; i++) {
603 struct kexec_segment *ksegment;
605 ksegment = &image->segment[i];
607 * Skip purgatory as it will be modified once we put digest
610 if (ksegment->kbuf == pi->purgatory_buf)
613 ret = crypto_shash_update(desc, ksegment->kbuf,
619 * Assume rest of the buffer is filled with zero and
620 * update digest accordingly.
622 nullsz = ksegment->memsz - ksegment->bufsz;
624 unsigned long bytes = nullsz;
626 if (bytes > zero_buf_sz)
628 ret = crypto_shash_update(desc, zero_buf, bytes);
637 sha_regions[j].start = ksegment->mem;
638 sha_regions[j].len = ksegment->memsz;
643 ret = crypto_shash_final(desc, digest);
645 goto out_free_digest;
646 ret = kexec_purgatory_get_set_symbol(image, "sha_regions",
647 sha_regions, sha_region_sz, 0);
649 goto out_free_digest;
651 ret = kexec_purgatory_get_set_symbol(image, "sha256_digest",
652 digest, SHA256_DIGEST_SIZE, 0);
654 goto out_free_digest;
659 out_free_sha_regions:
669 /* Actually load purgatory. Lot of code taken from kexec-tools */
670 static int __kexec_load_purgatory(struct kimage *image, unsigned long min,
671 unsigned long max, int top_down)
673 struct purgatory_info *pi = &image->purgatory_info;
674 unsigned long align, buf_align, bss_align, buf_sz, bss_sz, bss_pad;
675 unsigned long memsz, entry, load_addr, curr_load_addr, bss_addr, offset;
676 unsigned char *buf_addr, *src;
677 int i, ret = 0, entry_sidx = -1;
678 const Elf_Shdr *sechdrs_c;
679 Elf_Shdr *sechdrs = NULL;
680 void *purgatory_buf = NULL;
683 * sechdrs_c points to section headers in purgatory and are read
684 * only. No modifications allowed.
686 sechdrs_c = (void *)pi->ehdr + pi->ehdr->e_shoff;
689 * We can not modify sechdrs_c[] and its fields. It is read only.
690 * Copy it over to a local copy where one can store some temporary
691 * data and free it at the end. We need to modify ->sh_addr and
692 * ->sh_offset fields to keep track of permanent and temporary
693 * locations of sections.
695 sechdrs = vzalloc(pi->ehdr->e_shnum * sizeof(Elf_Shdr));
699 memcpy(sechdrs, sechdrs_c, pi->ehdr->e_shnum * sizeof(Elf_Shdr));
702 * We seem to have multiple copies of sections. First copy is which
703 * is embedded in kernel in read only section. Some of these sections
704 * will be copied to a temporary buffer and relocated. And these
705 * sections will finally be copied to their final destination at
708 * Use ->sh_offset to reflect section address in memory. It will
709 * point to original read only copy if section is not allocatable.
710 * Otherwise it will point to temporary copy which will be relocated.
712 * Use ->sh_addr to contain final address of the section where it
713 * will go during execution time.
715 for (i = 0; i < pi->ehdr->e_shnum; i++) {
716 if (sechdrs[i].sh_type == SHT_NOBITS)
719 sechdrs[i].sh_offset = (unsigned long)pi->ehdr +
720 sechdrs[i].sh_offset;
724 * Identify entry point section and make entry relative to section
727 entry = pi->ehdr->e_entry;
728 for (i = 0; i < pi->ehdr->e_shnum; i++) {
729 if (!(sechdrs[i].sh_flags & SHF_ALLOC))
732 if (!(sechdrs[i].sh_flags & SHF_EXECINSTR))
735 /* Make entry section relative */
736 if (sechdrs[i].sh_addr <= pi->ehdr->e_entry &&
737 ((sechdrs[i].sh_addr + sechdrs[i].sh_size) >
738 pi->ehdr->e_entry)) {
740 entry -= sechdrs[i].sh_addr;
745 /* Determine how much memory is needed to load relocatable object. */
751 for (i = 0; i < pi->ehdr->e_shnum; i++) {
752 if (!(sechdrs[i].sh_flags & SHF_ALLOC))
755 align = sechdrs[i].sh_addralign;
756 if (sechdrs[i].sh_type != SHT_NOBITS) {
757 if (buf_align < align)
759 buf_sz = ALIGN(buf_sz, align);
760 buf_sz += sechdrs[i].sh_size;
763 if (bss_align < align)
765 bss_sz = ALIGN(bss_sz, align);
766 bss_sz += sechdrs[i].sh_size;
770 /* Determine the bss padding required to align bss properly */
772 if (buf_sz & (bss_align - 1))
773 bss_pad = bss_align - (buf_sz & (bss_align - 1));
775 memsz = buf_sz + bss_pad + bss_sz;
777 /* Allocate buffer for purgatory */
778 purgatory_buf = vzalloc(buf_sz);
779 if (!purgatory_buf) {
784 if (buf_align < bss_align)
785 buf_align = bss_align;
787 /* Add buffer to segment list */
788 ret = kexec_add_buffer(image, purgatory_buf, buf_sz, memsz,
789 buf_align, min, max, top_down,
790 &pi->purgatory_load_addr);
794 /* Load SHF_ALLOC sections */
795 buf_addr = purgatory_buf;
796 load_addr = curr_load_addr = pi->purgatory_load_addr;
797 bss_addr = load_addr + buf_sz + bss_pad;
799 for (i = 0; i < pi->ehdr->e_shnum; i++) {
800 if (!(sechdrs[i].sh_flags & SHF_ALLOC))
803 align = sechdrs[i].sh_addralign;
804 if (sechdrs[i].sh_type != SHT_NOBITS) {
805 curr_load_addr = ALIGN(curr_load_addr, align);
806 offset = curr_load_addr - load_addr;
807 /* We already modifed ->sh_offset to keep src addr */
808 src = (char *) sechdrs[i].sh_offset;
809 memcpy(buf_addr + offset, src, sechdrs[i].sh_size);
811 /* Store load address and source address of section */
812 sechdrs[i].sh_addr = curr_load_addr;
815 * This section got copied to temporary buffer. Update
816 * ->sh_offset accordingly.
818 sechdrs[i].sh_offset = (unsigned long)(buf_addr + offset);
820 /* Advance to the next address */
821 curr_load_addr += sechdrs[i].sh_size;
823 bss_addr = ALIGN(bss_addr, align);
824 sechdrs[i].sh_addr = bss_addr;
825 bss_addr += sechdrs[i].sh_size;
829 /* Update entry point based on load address of text section */
831 entry += sechdrs[entry_sidx].sh_addr;
833 /* Make kernel jump to purgatory after shutdown */
834 image->start = entry;
836 /* Used later to get/set symbol values */
837 pi->sechdrs = sechdrs;
840 * Used later to identify which section is purgatory and skip it
843 pi->purgatory_buf = purgatory_buf;
847 vfree(purgatory_buf);
851 static int kexec_apply_relocations(struct kimage *image)
854 struct purgatory_info *pi = &image->purgatory_info;
855 Elf_Shdr *sechdrs = pi->sechdrs;
857 /* Apply relocations */
858 for (i = 0; i < pi->ehdr->e_shnum; i++) {
859 Elf_Shdr *section, *symtab;
861 if (sechdrs[i].sh_type != SHT_RELA &&
862 sechdrs[i].sh_type != SHT_REL)
866 * For section of type SHT_RELA/SHT_REL,
867 * ->sh_link contains section header index of associated
868 * symbol table. And ->sh_info contains section header
869 * index of section to which relocations apply.
871 if (sechdrs[i].sh_info >= pi->ehdr->e_shnum ||
872 sechdrs[i].sh_link >= pi->ehdr->e_shnum)
875 section = &sechdrs[sechdrs[i].sh_info];
876 symtab = &sechdrs[sechdrs[i].sh_link];
878 if (!(section->sh_flags & SHF_ALLOC))
882 * symtab->sh_link contain section header index of associated
885 if (symtab->sh_link >= pi->ehdr->e_shnum)
886 /* Invalid section number? */
890 * Respective architecture needs to provide support for applying
891 * relocations of type SHT_RELA/SHT_REL.
893 if (sechdrs[i].sh_type == SHT_RELA)
894 ret = arch_kexec_apply_relocations_add(pi->ehdr,
896 else if (sechdrs[i].sh_type == SHT_REL)
897 ret = arch_kexec_apply_relocations(pi->ehdr,
906 /* Load relocatable purgatory object and relocate it appropriately */
907 int kexec_load_purgatory(struct kimage *image, unsigned long min,
908 unsigned long max, int top_down,
909 unsigned long *load_addr)
911 struct purgatory_info *pi = &image->purgatory_info;
914 if (kexec_purgatory_size <= 0)
917 if (kexec_purgatory_size < sizeof(Elf_Ehdr))
920 pi->ehdr = (Elf_Ehdr *)kexec_purgatory;
922 if (memcmp(pi->ehdr->e_ident, ELFMAG, SELFMAG) != 0
923 || pi->ehdr->e_type != ET_REL
924 || !elf_check_arch(pi->ehdr)
925 || pi->ehdr->e_shentsize != sizeof(Elf_Shdr))
928 if (pi->ehdr->e_shoff >= kexec_purgatory_size
929 || (pi->ehdr->e_shnum * sizeof(Elf_Shdr) >
930 kexec_purgatory_size - pi->ehdr->e_shoff))
933 ret = __kexec_load_purgatory(image, min, max, top_down);
937 ret = kexec_apply_relocations(image);
941 *load_addr = pi->purgatory_load_addr;
945 vfree(pi->purgatory_buf);
949 static Elf_Sym *kexec_purgatory_find_symbol(struct purgatory_info *pi,
958 if (!pi->sechdrs || !pi->ehdr)
961 sechdrs = pi->sechdrs;
964 for (i = 0; i < ehdr->e_shnum; i++) {
965 if (sechdrs[i].sh_type != SHT_SYMTAB)
968 if (sechdrs[i].sh_link >= ehdr->e_shnum)
969 /* Invalid strtab section number */
971 strtab = (char *)sechdrs[sechdrs[i].sh_link].sh_offset;
972 syms = (Elf_Sym *)sechdrs[i].sh_offset;
974 /* Go through symbols for a match */
975 for (k = 0; k < sechdrs[i].sh_size/sizeof(Elf_Sym); k++) {
976 if (ELF_ST_BIND(syms[k].st_info) != STB_GLOBAL)
979 if (strcmp(strtab + syms[k].st_name, name) != 0)
982 if (syms[k].st_shndx == SHN_UNDEF ||
983 syms[k].st_shndx >= ehdr->e_shnum) {
984 pr_debug("Symbol: %s has bad section index %d.\n",
985 name, syms[k].st_shndx);
989 /* Found the symbol we are looking for */
997 void *kexec_purgatory_get_symbol_addr(struct kimage *image, const char *name)
999 struct purgatory_info *pi = &image->purgatory_info;
1003 sym = kexec_purgatory_find_symbol(pi, name);
1005 return ERR_PTR(-EINVAL);
1007 sechdr = &pi->sechdrs[sym->st_shndx];
1010 * Returns the address where symbol will finally be loaded after
1011 * kexec_load_segment()
1013 return (void *)(sechdr->sh_addr + sym->st_value);
1017 * Get or set value of a symbol. If "get_value" is true, symbol value is
1018 * returned in buf otherwise symbol value is set based on value in buf.
1020 int kexec_purgatory_get_set_symbol(struct kimage *image, const char *name,
1021 void *buf, unsigned int size, bool get_value)
1025 struct purgatory_info *pi = &image->purgatory_info;
1028 sym = kexec_purgatory_find_symbol(pi, name);
1032 if (sym->st_size != size) {
1033 pr_err("symbol %s size mismatch: expected %lu actual %u\n",
1034 name, (unsigned long)sym->st_size, size);
1038 sechdrs = pi->sechdrs;
1040 if (sechdrs[sym->st_shndx].sh_type == SHT_NOBITS) {
1041 pr_err("symbol %s is in a bss section. Cannot %s\n", name,
1042 get_value ? "get" : "set");
1046 sym_buf = (unsigned char *)sechdrs[sym->st_shndx].sh_offset +
1050 memcpy((void *)buf, sym_buf, size);
1052 memcpy((void *)sym_buf, buf, size);