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
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
|
/*
* Copyright 2017 The Chromium OS Authors. All rights reserved.
* Use of this source code is governed by a BSD-style license that can be
* found in the LICENSE file.
*/
#include <errno.h>
#include <fcntl.h>
#include <linux/memfd.h>
#include <pthread.h>
#include <stdint.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sys/mman.h>
#include <sys/syscall.h>
#include <time.h>
#include <unistd.h>
#include "crosvm.h"
#ifndef F_LINUX_SPECIFIC_BASE
#define F_LINUX_SPECIFIC_BASE 1024
#endif
#ifndef F_ADD_SEALS
#define F_ADD_SEALS (F_LINUX_SPECIFIC_BASE + 9)
#endif
#ifndef F_SEAL_SHRINK
#define F_SEAL_SHRINK 0x0002
#endif
#define LOAD_ADDRESS 0x1000
#define DATAMATCH_VAL 0x88
#define KILL_ADDRESS 0x4000
int g_kill_evt;
void *vcpu_thread(void *arg) {
struct crosvm_vcpu *vcpu = arg;
struct crosvm_vcpu_event evt;
int i = 0;
while (crosvm_vcpu_wait(vcpu, &evt) == 0) {
if (evt.kind == CROSVM_VCPU_EVENT_KIND_INIT) {
struct kvm_sregs sregs;
crosvm_vcpu_get_sregs(vcpu, &sregs);
sregs.cs.base = 0;
sregs.cs.selector = 0;
sregs.es.base = KILL_ADDRESS;
sregs.es.selector = 0;
crosvm_vcpu_set_sregs(vcpu, &sregs);
struct kvm_regs regs;
crosvm_vcpu_get_regs(vcpu, ®s);
regs.rflags = 2;
regs.rip = LOAD_ADDRESS;
regs.rax = DATAMATCH_VAL;
regs.rbx = DATAMATCH_VAL - 1;
crosvm_vcpu_set_regs(vcpu, ®s);
}
if (evt.kind == CROSVM_VCPU_EVENT_KIND_IO_ACCESS &&
evt.io_access.address_space == CROSVM_ADDRESS_SPACE_MMIO &&
evt.io_access.address == KILL_ADDRESS &&
evt.io_access.is_write &&
evt.io_access.length == 1 &&
evt.io_access.data[0] == 1)
{
uint64_t dummy = 1;
write(g_kill_evt, &dummy, sizeof(dummy));
return NULL;
}
crosvm_vcpu_resume(vcpu);
}
return NULL;
}
int main(int argc, char** argv) {
const uint8_t code[] = {
/*
0000 BAF803 mov dx,0x3f8
0003 88C3 mov bl,al
0005 EE out dx,al
0006 B000 mov al,0x0
0008 EE out dx,al
0009 88D8 mov al,bl
000B EE out dx,al
0014 26C606000001 mov byte [es:0x0],0x1
000C F4 hlt
*/
0xba, 0xf8, 0x03,
0x88, 0xc3,
0xee,
0xb0, 0x00,
0xee,
0x88, 0xd8,
0xee,
0x26, 0xc6, 0x06, 0x00, 0x00, 0x01,
0xf4,
};
struct crosvm *crosvm;
int ret = crosvm_connect(&crosvm);
if (ret) {
fprintf(stderr, "failed to connect to crosvm: %d\n", ret);
return 1;
}
g_kill_evt = crosvm_get_shutdown_eventfd(crosvm);
if (g_kill_evt < 0) {
fprintf(stderr, "failed to get kill eventfd: %d\n", g_kill_evt);
return 1;
}
ret = crosvm_reserve_range(crosvm, CROSVM_ADDRESS_SPACE_MMIO, KILL_ADDRESS, 1);
if (ret) {
fprintf(stderr, "failed to reserve mmio range: %d\n", ret);
return 1;
}
uint8_t datamatch = DATAMATCH_VAL;
struct crosvm_io *io;
ret = crosvm_create_io_event(crosvm, CROSVM_ADDRESS_SPACE_IOPORT, 0x3f8, 1, &datamatch, &io);
if (ret) {
fprintf(stderr, "failed to create ioevent: %d\n", ret);
return 1;
}
int ioeventfd = crosvm_io_event_fd(io);
int mem_size = 0x4000;
int mem_fd = syscall(SYS_memfd_create, "guest_mem", MFD_CLOEXEC | MFD_ALLOW_SEALING);
if (mem_fd < 0) {
fprintf(stderr, "failed to create guest memfd: %d\n", errno);
return 1;
}
ret = ftruncate(mem_fd, mem_size);
if (ret) {
fprintf(stderr, "failed to set size of guest memory: %d\n", errno);
return 1;
}
uint8_t *mem = mmap(NULL, mem_size, PROT_READ | PROT_WRITE, MAP_SHARED, mem_fd, 0);
if (mem == MAP_FAILED) {
fprintf(stderr, "failed to mmap guest memory: %d\n", errno);
return 1;
}
fcntl(mem_fd, F_ADD_SEALS, F_SEAL_SHRINK);
memcpy(mem + LOAD_ADDRESS, code, sizeof(code));
struct crosvm_memory *mem_obj;
ret = crosvm_create_memory(crosvm, mem_fd, 0, mem_size, 0, false, false, &mem_obj);
if (ret) {
fprintf(stderr, "failed to create memory in crosvm: %d\n", ret);
return 1;
}
/* get and creat a thread for each vcpu */
struct crosvm_vcpu *vcpus[32];
pthread_t vcpu_threads[32];
uint32_t vcpu_count;
for (vcpu_count = 0; vcpu_count < 32; vcpu_count++) {
ret = crosvm_get_vcpu(crosvm, vcpu_count, &vcpus[vcpu_count]);
if (ret == -ENOENT)
break;
if (ret) {
fprintf(stderr, "error while getting all vcpus: %d\n", ret);
return 1;
}
pthread_create(&vcpu_threads[vcpu_count], NULL, vcpu_thread, vcpus[vcpu_count]);
}
ret = crosvm_start(crosvm);
if (ret) {
fprintf(stderr, "failed to tell crosvm to start: %d\n", ret);
return 1;
}
uint64_t dummy;
read(g_kill_evt, &dummy, 8);
ret = read(ioeventfd, &dummy, sizeof(dummy));
if (ret == -1) {
fprintf(stderr, "failed to read ioeventfd: %d\n", errno);
return 1;
}
if (dummy != 2) {
fprintf(stderr, "ioeventfd was not triggered the expected number of times: %d\n", dummy);
return 1;
}
return 0;
}
|