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  1/*
  2 * Load ELF vmlinux file for the kexec_file_load syscall.
  3 *
  4 * Copyright (C) 2004  Adam Litke (agl@us.ibm.com)
  5 * Copyright (C) 2004  IBM Corp.
  6 * Copyright (C) 2005  R Sharada (sharada@in.ibm.com)
  7 * Copyright (C) 2006  Mohan Kumar M (mohan@in.ibm.com)
  8 * Copyright (C) 2016  IBM Corporation
  9 *
 10 * Based on kexec-tools' kexec-elf-exec.c and kexec-elf-ppc64.c.
 11 * Heavily modified for the kernel by
 12 * Thiago Jung Bauermann <bauerman@linux.vnet.ibm.com>.
 13 *
 14 * This program is free software; you can redistribute it and/or modify
 15 * it under the terms of the GNU General Public License as published by
 16 * the Free Software Foundation (version 2 of the License).
 17 *
 18 * This program is distributed in the hope that it will be useful,
 19 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 20 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 21 * GNU General Public License for more details.
 22 */
 23
 24#define pr_fmt(fmt)	"kexec_elf: " fmt
 25
 26#include <linux/elf.h>
 27#include <linux/kexec.h>
 28#include <linux/libfdt.h>
 29#include <linux/module.h>
 30#include <linux/of_fdt.h>
 31#include <linux/slab.h>
 32#include <linux/types.h>
 33
 34#define PURGATORY_STACK_SIZE	(16 * 1024)
 35
 36#define elf_addr_to_cpu	elf64_to_cpu
 37
 38#ifndef Elf_Rel
 39#define Elf_Rel		Elf64_Rel
 40#endif /* Elf_Rel */
 41
 42struct elf_info {
 43	/*
 44	 * Where the ELF binary contents are kept.
 45	 * Memory managed by the user of the struct.
 46	 */
 47	const char *buffer;
 48
 49	const struct elfhdr *ehdr;
 50	const struct elf_phdr *proghdrs;
 51	struct elf_shdr *sechdrs;
 52};
 53
 54static inline bool elf_is_elf_file(const struct elfhdr *ehdr)
 55{
 56       return memcmp(ehdr->e_ident, ELFMAG, SELFMAG) == 0;
 57}
 58
 59static uint64_t elf64_to_cpu(const struct elfhdr *ehdr, uint64_t value)
 60{
 61	if (ehdr->e_ident[EI_DATA] == ELFDATA2LSB)
 62		value = le64_to_cpu(value);
 63	else if (ehdr->e_ident[EI_DATA] == ELFDATA2MSB)
 64		value = be64_to_cpu(value);
 65
 66	return value;
 67}
 68
 69static uint16_t elf16_to_cpu(const struct elfhdr *ehdr, uint16_t value)
 70{
 71	if (ehdr->e_ident[EI_DATA] == ELFDATA2LSB)
 72		value = le16_to_cpu(value);
 73	else if (ehdr->e_ident[EI_DATA] == ELFDATA2MSB)
 74		value = be16_to_cpu(value);
 75
 76	return value;
 77}
 78
 79static uint32_t elf32_to_cpu(const struct elfhdr *ehdr, uint32_t value)
 80{
 81	if (ehdr->e_ident[EI_DATA] == ELFDATA2LSB)
 82		value = le32_to_cpu(value);
 83	else if (ehdr->e_ident[EI_DATA] == ELFDATA2MSB)
 84		value = be32_to_cpu(value);
 85
 86	return value;
 87}
 88
 89/**
 90 * elf_is_ehdr_sane - check that it is safe to use the ELF header
 91 * @buf_len:	size of the buffer in which the ELF file is loaded.
 92 */
 93static bool elf_is_ehdr_sane(const struct elfhdr *ehdr, size_t buf_len)
 94{
 95	if (ehdr->e_phnum > 0 && ehdr->e_phentsize != sizeof(struct elf_phdr)) {
 96		pr_debug("Bad program header size.\n");
 97		return false;
 98	} else if (ehdr->e_shnum > 0 &&
 99		   ehdr->e_shentsize != sizeof(struct elf_shdr)) {
100		pr_debug("Bad section header size.\n");
101		return false;
102	} else if (ehdr->e_ident[EI_VERSION] != EV_CURRENT ||
103		   ehdr->e_version != EV_CURRENT) {
104		pr_debug("Unknown ELF version.\n");
105		return false;
106	}
107
108	if (ehdr->e_phoff > 0 && ehdr->e_phnum > 0) {
109		size_t phdr_size;
110
111		/*
112		 * e_phnum is at most 65535 so calculating the size of the
113		 * program header cannot overflow.
114		 */
115		phdr_size = sizeof(struct elf_phdr) * ehdr->e_phnum;
116
117		/* Sanity check the program header table location. */
118		if (ehdr->e_phoff + phdr_size < ehdr->e_phoff) {
119			pr_debug("Program headers at invalid location.\n");
120			return false;
121		} else if (ehdr->e_phoff + phdr_size > buf_len) {
122			pr_debug("Program headers truncated.\n");
123			return false;
124		}
125	}
126
127	if (ehdr->e_shoff > 0 && ehdr->e_shnum > 0) {
128		size_t shdr_size;
129
130		/*
131		 * e_shnum is at most 65536 so calculating
132		 * the size of the section header cannot overflow.
133		 */
134		shdr_size = sizeof(struct elf_shdr) * ehdr->e_shnum;
135
136		/* Sanity check the section header table location. */
137		if (ehdr->e_shoff + shdr_size < ehdr->e_shoff) {
138			pr_debug("Section headers at invalid location.\n");
139			return false;
140		} else if (ehdr->e_shoff + shdr_size > buf_len) {
141			pr_debug("Section headers truncated.\n");
142			return false;
143		}
144	}
145
146	return true;
147}
148
149static int elf_read_ehdr(const char *buf, size_t len, struct elfhdr *ehdr)
150{
151	struct elfhdr *buf_ehdr;
152
153	if (len < sizeof(*buf_ehdr)) {
154		pr_debug("Buffer is too small to hold ELF header.\n");
155		return -ENOEXEC;
156	}
157
158	memset(ehdr, 0, sizeof(*ehdr));
159	memcpy(ehdr->e_ident, buf, sizeof(ehdr->e_ident));
160	if (!elf_is_elf_file(ehdr)) {
161		pr_debug("No ELF header magic.\n");
162		return -ENOEXEC;
163	}
164
165	if (ehdr->e_ident[EI_CLASS] != ELF_CLASS) {
166		pr_debug("Not a supported ELF class.\n");
167		return -ENOEXEC;
168	} else  if (ehdr->e_ident[EI_DATA] != ELFDATA2LSB &&
169		ehdr->e_ident[EI_DATA] != ELFDATA2MSB) {
170		pr_debug("Not a supported ELF data format.\n");
171		return -ENOEXEC;
172	}
173
174	buf_ehdr = (struct elfhdr *) buf;
175	if (elf16_to_cpu(ehdr, buf_ehdr->e_ehsize) != sizeof(*buf_ehdr)) {
176		pr_debug("Bad ELF header size.\n");
177		return -ENOEXEC;
178	}
179
180	ehdr->e_type      = elf16_to_cpu(ehdr, buf_ehdr->e_type);
181	ehdr->e_machine   = elf16_to_cpu(ehdr, buf_ehdr->e_machine);
182	ehdr->e_version   = elf32_to_cpu(ehdr, buf_ehdr->e_version);
183	ehdr->e_entry     = elf_addr_to_cpu(ehdr, buf_ehdr->e_entry);
184	ehdr->e_phoff     = elf_addr_to_cpu(ehdr, buf_ehdr->e_phoff);
185	ehdr->e_shoff     = elf_addr_to_cpu(ehdr, buf_ehdr->e_shoff);
186	ehdr->e_flags     = elf32_to_cpu(ehdr, buf_ehdr->e_flags);
187	ehdr->e_phentsize = elf16_to_cpu(ehdr, buf_ehdr->e_phentsize);
188	ehdr->e_phnum     = elf16_to_cpu(ehdr, buf_ehdr->e_phnum);
189	ehdr->e_shentsize = elf16_to_cpu(ehdr, buf_ehdr->e_shentsize);
190	ehdr->e_shnum     = elf16_to_cpu(ehdr, buf_ehdr->e_shnum);
191	ehdr->e_shstrndx  = elf16_to_cpu(ehdr, buf_ehdr->e_shstrndx);
192
193	return elf_is_ehdr_sane(ehdr, len) ? 0 : -ENOEXEC;
194}
195
196/**
197 * elf_is_phdr_sane - check that it is safe to use the program header
198 * @buf_len:	size of the buffer in which the ELF file is loaded.
199 */
200static bool elf_is_phdr_sane(const struct elf_phdr *phdr, size_t buf_len)
201{
202
203	if (phdr->p_offset + phdr->p_filesz < phdr->p_offset) {
204		pr_debug("ELF segment location wraps around.\n");
205		return false;
206	} else if (phdr->p_offset + phdr->p_filesz > buf_len) {
207		pr_debug("ELF segment not in file.\n");
208		return false;
209	} else if (phdr->p_paddr + phdr->p_memsz < phdr->p_paddr) {
210		pr_debug("ELF segment address wraps around.\n");
211		return false;
212	}
213
214	return true;
215}
216
217static int elf_read_phdr(const char *buf, size_t len, struct elf_info *elf_info,
218			 int idx)
219{
220	/* Override the const in proghdrs, we are the ones doing the loading. */
221	struct elf_phdr *phdr = (struct elf_phdr *) &elf_info->proghdrs[idx];
222	const char *pbuf;
223	struct elf_phdr *buf_phdr;
224
225	pbuf = buf + elf_info->ehdr->e_phoff + (idx * sizeof(*buf_phdr));
226	buf_phdr = (struct elf_phdr *) pbuf;
227
228	phdr->p_type   = elf32_to_cpu(elf_info->ehdr, buf_phdr->p_type);
229	phdr->p_offset = elf_addr_to_cpu(elf_info->ehdr, buf_phdr->p_offset);
230	phdr->p_paddr  = elf_addr_to_cpu(elf_info->ehdr, buf_phdr->p_paddr);
231	phdr->p_vaddr  = elf_addr_to_cpu(elf_info->ehdr, buf_phdr->p_vaddr);
232	phdr->p_flags  = elf32_to_cpu(elf_info->ehdr, buf_phdr->p_flags);
233
234	/*
235	 * The following fields have a type equivalent to Elf_Addr
236	 * both in 32 bit and 64 bit ELF.
237	 */
238	phdr->p_filesz = elf_addr_to_cpu(elf_info->ehdr, buf_phdr->p_filesz);
239	phdr->p_memsz  = elf_addr_to_cpu(elf_info->ehdr, buf_phdr->p_memsz);
240	phdr->p_align  = elf_addr_to_cpu(elf_info->ehdr, buf_phdr->p_align);
241
242	return elf_is_phdr_sane(phdr, len) ? 0 : -ENOEXEC;
243}
244
245/**
246 * elf_read_phdrs - read the program headers from the buffer
247 *
248 * This function assumes that the program header table was checked for sanity.
249 * Use elf_is_ehdr_sane() if it wasn't.
250 */
251static int elf_read_phdrs(const char *buf, size_t len,
252			  struct elf_info *elf_info)
253{
254	size_t phdr_size, i;
255	const struct elfhdr *ehdr = elf_info->ehdr;
256
257	/*
258	 * e_phnum is at most 65535 so calculating the size of the
259	 * program header cannot overflow.
260	 */
261	phdr_size = sizeof(struct elf_phdr) * ehdr->e_phnum;
262
263	elf_info->proghdrs = kzalloc(phdr_size, GFP_KERNEL);
264	if (!elf_info->proghdrs)
265		return -ENOMEM;
266
267	for (i = 0; i < ehdr->e_phnum; i++) {
268		int ret;
269
270		ret = elf_read_phdr(buf, len, elf_info, i);
271		if (ret) {
272			kfree(elf_info->proghdrs);
273			elf_info->proghdrs = NULL;
274			return ret;
275		}
276	}
277
278	return 0;
279}
280
281/**
282 * elf_is_shdr_sane - check that it is safe to use the section header
283 * @buf_len:	size of the buffer in which the ELF file is loaded.
284 */
285static bool elf_is_shdr_sane(const struct elf_shdr *shdr, size_t buf_len)
286{
287	bool size_ok;
288
289	/* SHT_NULL headers have undefined values, so we can't check them. */
290	if (shdr->sh_type == SHT_NULL)
291		return true;
292
293	/* Now verify sh_entsize */
294	switch (shdr->sh_type) {
295	case SHT_SYMTAB:
296		size_ok = shdr->sh_entsize == sizeof(Elf_Sym);
297		break;
298	case SHT_RELA:
299		size_ok = shdr->sh_entsize == sizeof(Elf_Rela);
300		break;
301	case SHT_DYNAMIC:
302		size_ok = shdr->sh_entsize == sizeof(Elf_Dyn);
303		break;
304	case SHT_REL:
305		size_ok = shdr->sh_entsize == sizeof(Elf_Rel);
306		break;
307	case SHT_NOTE:
308	case SHT_PROGBITS:
309	case SHT_HASH:
310	case SHT_NOBITS:
311	default:
312		/*
313		 * This is a section whose entsize requirements
314		 * I don't care about.  If I don't know about
315		 * the section I can't care about it's entsize
316		 * requirements.
317		 */
318		size_ok = true;
319		break;
320	}
321
322	if (!size_ok) {
323		pr_debug("ELF section with wrong entry size.\n");
324		return false;
325	} else if (shdr->sh_addr + shdr->sh_size < shdr->sh_addr) {
326		pr_debug("ELF section address wraps around.\n");
327		return false;
328	}
329
330	if (shdr->sh_type != SHT_NOBITS) {
331		if (shdr->sh_offset + shdr->sh_size < shdr->sh_offset) {
332			pr_debug("ELF section location wraps around.\n");
333			return false;
334		} else if (shdr->sh_offset + shdr->sh_size > buf_len) {
335			pr_debug("ELF section not in file.\n");
336			return false;
337		}
338	}
339
340	return true;
341}
342
343static int elf_read_shdr(const char *buf, size_t len, struct elf_info *elf_info,
344			 int idx)
345{
346	struct elf_shdr *shdr = &elf_info->sechdrs[idx];
347	const struct elfhdr *ehdr = elf_info->ehdr;
348	const char *sbuf;
349	struct elf_shdr *buf_shdr;
350
351	sbuf = buf + ehdr->e_shoff + idx * sizeof(*buf_shdr);
352	buf_shdr = (struct elf_shdr *) sbuf;
353
354	shdr->sh_name      = elf32_to_cpu(ehdr, buf_shdr->sh_name);
355	shdr->sh_type      = elf32_to_cpu(ehdr, buf_shdr->sh_type);
356	shdr->sh_addr      = elf_addr_to_cpu(ehdr, buf_shdr->sh_addr);
357	shdr->sh_offset    = elf_addr_to_cpu(ehdr, buf_shdr->sh_offset);
358	shdr->sh_link      = elf32_to_cpu(ehdr, buf_shdr->sh_link);
359	shdr->sh_info      = elf32_to_cpu(ehdr, buf_shdr->sh_info);
360
361	/*
362	 * The following fields have a type equivalent to Elf_Addr
363	 * both in 32 bit and 64 bit ELF.
364	 */
365	shdr->sh_flags     = elf_addr_to_cpu(ehdr, buf_shdr->sh_flags);
366	shdr->sh_size      = elf_addr_to_cpu(ehdr, buf_shdr->sh_size);
367	shdr->sh_addralign = elf_addr_to_cpu(ehdr, buf_shdr->sh_addralign);
368	shdr->sh_entsize   = elf_addr_to_cpu(ehdr, buf_shdr->sh_entsize);
369
370	return elf_is_shdr_sane(shdr, len) ? 0 : -ENOEXEC;
371}
372
373/**
374 * elf_read_shdrs - read the section headers from the buffer
375 *
376 * This function assumes that the section header table was checked for sanity.
377 * Use elf_is_ehdr_sane() if it wasn't.
378 */
379static int elf_read_shdrs(const char *buf, size_t len,
380			  struct elf_info *elf_info)
381{
382	size_t shdr_size, i;
383
384	/*
385	 * e_shnum is at most 65536 so calculating
386	 * the size of the section header cannot overflow.
387	 */
388	shdr_size = sizeof(struct elf_shdr) * elf_info->ehdr->e_shnum;
389
390	elf_info->sechdrs = kzalloc(shdr_size, GFP_KERNEL);
391	if (!elf_info->sechdrs)
392		return -ENOMEM;
393
394	for (i = 0; i < elf_info->ehdr->e_shnum; i++) {
395		int ret;
396
397		ret = elf_read_shdr(buf, len, elf_info, i);
398		if (ret) {
399			kfree(elf_info->sechdrs);
400			elf_info->sechdrs = NULL;
401			return ret;
402		}
403	}
404
405	return 0;
406}
407
408/**
409 * elf_read_from_buffer - read ELF file and sets up ELF header and ELF info
410 * @buf:	Buffer to read ELF file from.
411 * @len:	Size of @buf.
412 * @ehdr:	Pointer to existing struct which will be populated.
413 * @elf_info:	Pointer to existing struct which will be populated.
414 *
415 * This function allows reading ELF files with different byte order than
416 * the kernel, byte-swapping the fields as needed.
417 *
418 * Return:
419 * On success returns 0, and the caller should call elf_free_info(elf_info) to
420 * free the memory allocated for the section and program headers.
421 */
422int elf_read_from_buffer(const char *buf, size_t len, struct elfhdr *ehdr,
423			 struct elf_info *elf_info)
424{
425	int ret;
426
427	ret = elf_read_ehdr(buf, len, ehdr);
428	if (ret)
429		return ret;
430
431	elf_info->buffer = buf;
432	elf_info->ehdr = ehdr;
433	if (ehdr->e_phoff > 0 && ehdr->e_phnum > 0) {
434		ret = elf_read_phdrs(buf, len, elf_info);
435		if (ret)
436			return ret;
437	}
438	if (ehdr->e_shoff > 0 && ehdr->e_shnum > 0) {
439		ret = elf_read_shdrs(buf, len, elf_info);
440		if (ret) {
441			kfree(elf_info->proghdrs);
442			return ret;
443		}
444	}
445
446	return 0;
447}
448
449/**
450 * elf_free_info - free memory allocated by elf_read_from_buffer
451 */
452void elf_free_info(struct elf_info *elf_info)
453{
454	kfree(elf_info->proghdrs);
455	kfree(elf_info->sechdrs);
456	memset(elf_info, 0, sizeof(*elf_info));
457}
458/**
459 * build_elf_exec_info - read ELF executable and check that we can use it
460 */
461static int build_elf_exec_info(const char *buf, size_t len, struct elfhdr *ehdr,
462			       struct elf_info *elf_info)
463{
464	int i;
465	int ret;
466
467	ret = elf_read_from_buffer(buf, len, ehdr, elf_info);
468	if (ret)
469		return ret;
470
471	/* Big endian vmlinux has type ET_DYN. */
472	if (ehdr->e_type != ET_EXEC && ehdr->e_type != ET_DYN) {
473		pr_err("Not an ELF executable.\n");
474		goto error;
475	} else if (!elf_info->proghdrs) {
476		pr_err("No ELF program header.\n");
477		goto error;
478	}
479
480	for (i = 0; i < ehdr->e_phnum; i++) {
481		/*
482		 * Kexec does not support loading interpreters.
483		 * In addition this check keeps us from attempting
484		 * to kexec ordinay executables.
485		 */
486		if (elf_info->proghdrs[i].p_type == PT_INTERP) {
487			pr_err("Requires an ELF interpreter.\n");
488			goto error;
489		}
490	}
491
492	return 0;
493error:
494	elf_free_info(elf_info);
495	return -ENOEXEC;
496}
497
498static int elf64_probe(const char *buf, unsigned long len)
499{
500	struct elfhdr ehdr;
501	struct elf_info elf_info;
502	int ret;
503
504	ret = build_elf_exec_info(buf, len, &ehdr, &elf_info);
505	if (ret)
506		return ret;
507
508	elf_free_info(&elf_info);
509
510	return elf_check_arch(&ehdr) ? 0 : -ENOEXEC;
511}
512
513/**
514 * elf_exec_load - load ELF executable image
515 * @lowest_load_addr:	On return, will be the address where the first PT_LOAD
516 *			section will be loaded in memory.
517 *
518 * Return:
519 * 0 on success, negative value on failure.
520 */
521static int elf_exec_load(struct kimage *image, struct elfhdr *ehdr,
522			 struct elf_info *elf_info,
523			 unsigned long *lowest_load_addr)
524{
525	unsigned long base = 0, lowest_addr = UINT_MAX;
526	int ret;
527	size_t i;
528	struct kexec_buf kbuf = { .image = image, .buf_max = ppc64_rma_size,
529				  .top_down = false };
530
531	/* Read in the PT_LOAD segments. */
532	for (i = 0; i < ehdr->e_phnum; i++) {
533		unsigned long load_addr;
534		size_t size;
535		const struct elf_phdr *phdr;
536
537		phdr = &elf_info->proghdrs[i];
538		if (phdr->p_type != PT_LOAD)
539			continue;
540
541		size = phdr->p_filesz;
542		if (size > phdr->p_memsz)
543			size = phdr->p_memsz;
544
545		kbuf.buffer = (void *) elf_info->buffer + phdr->p_offset;
546		kbuf.bufsz = size;
547		kbuf.memsz = phdr->p_memsz;
548		kbuf.buf_align = phdr->p_align;
549		kbuf.buf_min = phdr->p_paddr + base;
550		ret = kexec_add_buffer(&kbuf);
551		if (ret)
552			goto out;
553		load_addr = kbuf.mem;
554
555		if (load_addr < lowest_addr)
556			lowest_addr = load_addr;
557	}
558
559	/* Update entry point to reflect new load address. */
560	ehdr->e_entry += base;
561
562	*lowest_load_addr = lowest_addr;
563	ret = 0;
564 out:
565	return ret;
566}
567
568static void *elf64_load(struct kimage *image, char *kernel_buf,
569			unsigned long kernel_len, char *initrd,
570			unsigned long initrd_len, char *cmdline,
571			unsigned long cmdline_len)
572{
573	int ret;
574	unsigned int fdt_size;
575	unsigned long kernel_load_addr;
576	unsigned long initrd_load_addr = 0, fdt_load_addr;
577	void *fdt;
578	const void *slave_code;
579	struct elfhdr ehdr;
580	struct elf_info elf_info;
581	struct kexec_buf kbuf = { .image = image, .buf_min = 0,
582				  .buf_max = ppc64_rma_size };
583	struct kexec_buf pbuf = { .image = image, .buf_min = 0,
584				  .buf_max = ppc64_rma_size, .top_down = true };
585
586	ret = build_elf_exec_info(kernel_buf, kernel_len, &ehdr, &elf_info);
587	if (ret)
588		goto out;
589
590	ret = elf_exec_load(image, &ehdr, &elf_info, &kernel_load_addr);
591	if (ret)
592		goto out;
593
594	pr_debug("Loaded the kernel at 0x%lx\n", kernel_load_addr);
595
596	ret = kexec_load_purgatory(image, &pbuf);
597	if (ret) {
598		pr_err("Loading purgatory failed.\n");
599		goto out;
600	}
601
602	pr_debug("Loaded purgatory at 0x%lx\n", pbuf.mem);
603
604	if (initrd != NULL) {
605		kbuf.buffer = initrd;
606		kbuf.bufsz = kbuf.memsz = initrd_len;
607		kbuf.buf_align = PAGE_SIZE;
608		kbuf.top_down = false;
609		ret = kexec_add_buffer(&kbuf);
610		if (ret)
611			goto out;
612		initrd_load_addr = kbuf.mem;
613
614		pr_debug("Loaded initrd at 0x%lx\n", initrd_load_addr);
615	}
616
617	fdt_size = fdt_totalsize(initial_boot_params) * 2;
618	fdt = kmalloc(fdt_size, GFP_KERNEL);
619	if (!fdt) {
620		pr_err("Not enough memory for the device tree.\n");
621		ret = -ENOMEM;
622		goto out;
623	}
624	ret = fdt_open_into(initial_boot_params, fdt, fdt_size);
625	if (ret < 0) {
626		pr_err("Error setting up the new device tree.\n");
627		ret = -EINVAL;
628		goto out;
629	}
630
631	ret = setup_new_fdt(image, fdt, initrd_load_addr, initrd_len, cmdline);
632	if (ret)
633		goto out;
634
635	fdt_pack(fdt);
636
637	kbuf.buffer = fdt;
638	kbuf.bufsz = kbuf.memsz = fdt_size;
639	kbuf.buf_align = PAGE_SIZE;
640	kbuf.top_down = true;
641	ret = kexec_add_buffer(&kbuf);
642	if (ret)
643		goto out;
644	fdt_load_addr = kbuf.mem;
645
646	pr_debug("Loaded device tree at 0x%lx\n", fdt_load_addr);
647
648	slave_code = elf_info.buffer + elf_info.proghdrs[0].p_offset;
649	ret = setup_purgatory(image, slave_code, fdt, kernel_load_addr,
650			      fdt_load_addr);
651	if (ret)
652		pr_err("Error setting up the purgatory.\n");
653
654out:
655	elf_free_info(&elf_info);
656
657	/* Make kimage_file_post_load_cleanup free the fdt buffer for us. */
658	return ret ? ERR_PTR(ret) : fdt;
659}
660
661const struct kexec_file_ops kexec_elf64_ops = {
662	.probe = elf64_probe,
663	.load = elf64_load,
664};