diff options
Diffstat (limited to 'arch/arm64/kernel/kexec_image.c')
| -rw-r--r-- | arch/arm64/kernel/kexec_image.c | 130 |
1 files changed, 130 insertions, 0 deletions
diff --git a/arch/arm64/kernel/kexec_image.c b/arch/arm64/kernel/kexec_image.c new file mode 100644 index 000000000000..07bf740bea91 --- /dev/null +++ b/arch/arm64/kernel/kexec_image.c @@ -0,0 +1,130 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Kexec image loader + + * Copyright (C) 2018 Linaro Limited + * Author: AKASHI Takahiro <takahiro.akashi@linaro.org> + */ + +#define pr_fmt(fmt) "kexec_file(Image): " fmt + +#include <linux/err.h> +#include <linux/errno.h> +#include <linux/kernel.h> +#include <linux/kexec.h> +#include <linux/pe.h> +#include <linux/string.h> +#include <linux/verification.h> +#include <asm/byteorder.h> +#include <asm/cpufeature.h> +#include <asm/image.h> +#include <asm/memory.h> + +static int image_probe(const char *kernel_buf, unsigned long kernel_len) +{ + const struct arm64_image_header *h = + (const struct arm64_image_header *)(kernel_buf); + + if (!h || (kernel_len < sizeof(*h))) + return -EINVAL; + + if (memcmp(&h->magic, ARM64_IMAGE_MAGIC, sizeof(h->magic))) + return -EINVAL; + + return 0; +} + +static void *image_load(struct kimage *image, + char *kernel, unsigned long kernel_len, + char *initrd, unsigned long initrd_len, + char *cmdline, unsigned long cmdline_len) +{ + struct arm64_image_header *h; + u64 flags, value; + bool be_image, be_kernel; + struct kexec_buf kbuf; + unsigned long text_offset; + struct kexec_segment *kernel_segment; + int ret; + + /* We don't support crash kernels yet. */ + if (image->type == KEXEC_TYPE_CRASH) + return ERR_PTR(-EOPNOTSUPP); + + /* + * We require a kernel with an unambiguous Image header. Per + * Documentation/booting.txt, this is the case when image_size + * is non-zero (practically speaking, since v3.17). + */ + h = (struct arm64_image_header *)kernel; + if (!h->image_size) + return ERR_PTR(-EINVAL); + + /* Check cpu features */ + flags = le64_to_cpu(h->flags); + be_image = arm64_image_flag_field(flags, ARM64_IMAGE_FLAG_BE); + be_kernel = IS_ENABLED(CONFIG_CPU_BIG_ENDIAN); + if ((be_image != be_kernel) && !system_supports_mixed_endian()) + return ERR_PTR(-EINVAL); + + value = arm64_image_flag_field(flags, ARM64_IMAGE_FLAG_PAGE_SIZE); + if (((value == ARM64_IMAGE_FLAG_PAGE_SIZE_4K) && + !system_supports_4kb_granule()) || + ((value == ARM64_IMAGE_FLAG_PAGE_SIZE_64K) && + !system_supports_64kb_granule()) || + ((value == ARM64_IMAGE_FLAG_PAGE_SIZE_16K) && + !system_supports_16kb_granule())) + return ERR_PTR(-EINVAL); + + /* Load the kernel */ + kbuf.image = image; + kbuf.buf_min = 0; + kbuf.buf_max = ULONG_MAX; + kbuf.top_down = false; + + kbuf.buffer = kernel; + kbuf.bufsz = kernel_len; + kbuf.mem = 0; + kbuf.memsz = le64_to_cpu(h->image_size); + text_offset = le64_to_cpu(h->text_offset); + kbuf.buf_align = MIN_KIMG_ALIGN; + + /* Adjust kernel segment with TEXT_OFFSET */ + kbuf.memsz += text_offset; + + ret = kexec_add_buffer(&kbuf); + if (ret) + return ERR_PTR(ret); + + kernel_segment = &image->segment[image->nr_segments - 1]; + kernel_segment->mem += text_offset; + kernel_segment->memsz -= text_offset; + image->start = kernel_segment->mem; + + pr_debug("Loaded kernel at 0x%lx bufsz=0x%lx memsz=0x%lx\n", + kernel_segment->mem, kbuf.bufsz, + kernel_segment->memsz); + + /* Load additional data */ + ret = load_other_segments(image, + kernel_segment->mem, kernel_segment->memsz, + initrd, initrd_len, cmdline); + + return ERR_PTR(ret); +} + +#ifdef CONFIG_KEXEC_IMAGE_VERIFY_SIG +static int image_verify_sig(const char *kernel, unsigned long kernel_len) +{ + return verify_pefile_signature(kernel, kernel_len, NULL, + VERIFYING_KEXEC_PE_SIGNATURE); +} +#endif + +const struct kexec_file_ops kexec_image_ops = { + .probe = image_probe, + .load = image_load, +#ifdef CONFIG_KEXEC_IMAGE_VERIFY_SIG + .verify_sig = image_verify_sig, +#endif +}; |