1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
|
// 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, kernel_segment_number;
struct kexec_segment *kernel_segment;
int ret;
/*
* We require a kernel with an unambiguous Image header. Per
* Documentation/arm64/booting.rst, 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 = KEXEC_BUF_MEM_UNKNOWN;
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;
kernel_segment_number = image->nr_segments;
/*
* The location of the kernel segment may make it impossible to satisfy
* the other segment requirements, so we try repeatedly to find a
* location that will work.
*/
while ((ret = kexec_add_buffer(&kbuf)) == 0) {
/* Try to load additional data */
kernel_segment = &image->segment[kernel_segment_number];
ret = load_other_segments(image, kernel_segment->mem,
kernel_segment->memsz, initrd,
initrd_len, cmdline);
if (!ret)
break;
/*
* We couldn't find space for the other segments; erase the
* kernel segment and try the next available hole.
*/
image->nr_segments -= 1;
kbuf.buf_min = kernel_segment->mem + kernel_segment->memsz;
kbuf.mem = KEXEC_BUF_MEM_UNKNOWN;
}
if (ret) {
pr_err("Could not find any suitable kernel location!");
return ERR_PTR(ret);
}
kernel_segment = &image->segment[kernel_segment_number];
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);
return NULL;
}
#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
};
|
