syzkaller/executor/kvm.S
Dmitry Vyukov 4ee789185b sys: improve kvm description
Allow fuzzer to change types of segment descriptors.
Alter more flags.
Allow fuzzer to do a random vmwrite.
2017-01-28 19:58:31 +01:00

326 lines
8.1 KiB
ArmAsm

// Copyright 2017 syzkaller project authors. All rights reserved.
// Use of this source code is governed by Apache 2 LICENSE that can be found in the LICENSE file.
// kvm_gen.cc generates machine code from this file and saves it into kvm.S.h.
// +build
#include "kvm.h"
.global kvm_asm64_enable_long, kvm_asm64_enable_long_end
kvm_asm64_enable_long:
.code32
mov %cr0, %eax
or $0x80000000, %eax
mov %eax, %cr0
ljmp $SEL_CS64, NEXT_INSN
.code64
mov $SEL_TSS64, %rax
ltr %ax
kvm_asm64_enable_long_end:
nop
.global kvm_asm32_paged, kvm_asm32_paged_end
kvm_asm32_paged:
.code32
mov %cr0, %eax
or $0x80000000, %eax
mov %eax, %cr0
kvm_asm32_paged_end:
nop
.global kvm_asm32_vm86, kvm_asm32_vm86_end
kvm_asm32_vm86:
.code32
mov $SEL_TSS32, %ax
ltr %ax
ljmp $SEL_TSS32_VM86, $0
kvm_asm32_vm86_end:
nop
.global kvm_asm32_paged_vm86, kvm_asm32_paged_vm86_end
kvm_asm32_paged_vm86:
.code32
mov %cr0, %eax
or $0x80000000, %eax
mov %eax, %cr0
mov $SEL_TSS32, %ax
ltr %ax
ljmp $SEL_TSS32_VM86, $0
kvm_asm32_paged_vm86_end:
nop
.global kvm_asm64_vm86, kvm_asm64_vm86_end
kvm_asm64_vm86:
.code32
mov %cr0, %eax
or $0x80000000, %eax
mov %eax, %cr0
mov $SEL_TSS32, %ax
ltr %ax
ljmp $SEL_TSS32_VM86, $0
kvm_asm64_vm86_end:
nop
.global kvm_asm16_cpl3, kvm_asm16_cpl3_end
kvm_asm16_cpl3:
.code16
mov %cr0, %eax
or $1, %eax
mov %eax, %cr0
mov $SEL_TSS16, %ax
ltr %ax
mov $SEL_DS16_CPL3, %ax
mov %ax, %ds
mov %ax, %es
mov %ax, %fs
mov %ax, %gs
mov $0x100, %sp
movw $PREFIX_SIZE, 0x100
movw $SEL_CS16_CPL3, 0x102
movw $0x100, 0x104
movw $SEL_DS16_CPL3, 0x106
lret
kvm_asm16_cpl3_end:
nop
.global kvm_asm64_cpl3, kvm_asm64_cpl3_end
kvm_asm64_cpl3:
.code32
mov %cr0, %eax
or $0x80000000, %eax
mov %eax, %cr0
ljmp $SEL_CS64, NEXT_INSN
.code64
mov $SEL_TSS64, %rax
ltr %ax
mov $SEL_DS64_CPL3, %rax
mov %ax, %ds
mov %ax, %es
mov %ax, %fs
mov %ax, %gs
mov $ADDR_STACK0, %rsp
movq $PREFIX_SIZE, 0(%rsp)
movq $SEL_CS64_CPL3, 4(%rsp)
movq $ADDR_STACK0, 8(%rsp)
movq $SEL_DS64_CPL3, 12(%rsp)
lret
kvm_asm64_cpl3_end:
nop
.global kvm_asm64_init_vm, kvm_asm64_init_vm_end
kvm_asm64_init_vm:
.code32
// CR0.PG = 1
mov %cr0, %eax
or $0x80000000, %eax
mov %eax, %cr0
ljmp $SEL_CS64, NEXT_INSN
.code64
mov $SEL_TSS64, %rax
ltr %ax
// Enable and lock non-SMM VM
mov $MSR_IA32_FEATURE_CONTROL, %rcx
rdmsr
or $0x5, %rax
wrmsr
// CR4.VMXE = 1
mov %cr4, %rax
or $0x2000, %rax
mov %rax, %cr4
// Write VMCS revision into VMXON and VMCS regions
mov $MSR_IA32_VMX_BASIC, %rcx
rdmsr
mov $ADDR_VAR_VMXON, %rdx
mov %eax, (%rdx)
mov $ADDR_VAR_VMCS, %rdx
mov %eax, (%rdx)
mov $ADDR_VAR_VMXON_PTR, %rax
vmxon (%rax)
mov $ADDR_VAR_VMCS_PTR, %rax
vmclear (%rax)
vmptrld (%rax)
#define VMSET(FIELD, VAL) \
mov $FIELD, %rdx; \
mov VAL, %rax; \
vmwrite %rax, %rdx; \
/**/
#define VMSET_LIMITED(FIELD, VAL, MSR) \
mov $MSR, %rcx; \
rdmsr; \
or VAL, %rax; \
and %rdx, %rax; \
mov $FIELD, %rdx; \
vmwrite %rax, %rdx; \
/**/
VMSET_LIMITED(0x00004000, $0x3f, 0x481) // Pin-based VM-execution controls
//VMSET_LIMITED(0x00004002, $0x61999e84, 0x482) // Primary processor-based VM-execution controls
VMSET(0x00004002, $0xf3999e84)
VMSET(0x0000401E, $((1<<0) | (1<<7))) // Secondary processor-based VM-execution controls
VMSET_LIMITED(0x0000400C, $0x36fff, 0x483) // VM-exit controls (F6FFF)
VMSET_LIMITED(0x00004012, $0x17ff, 0x484) // VM-entry controls (51FF)
VMSET(0x00002C04, $0) // Host IA32_PERF_GLOBAL_CTR
VMSET(0x00002800, $0xffffffffffffffff) // VMCS link pointer
VMSET(0x00000C02, $SEL_CS64) // host CS
mov $SEL_DS64, %rax
mov $0x00000C00, %rdx // host ES
vmwrite %rax, %rdx
mov $0x00000C04, %rdx // host SS
vmwrite %rax, %rdx
mov $0x00000C06, %rdx // host DS
vmwrite %rax, %rdx
mov $0x00000C08, %rdx // host FS
vmwrite %rax, %rdx
mov $0x00000C0A, %rdx // host GS
vmwrite %rax, %rdx
mov $SEL_TSS64, %rax
mov $0x00000C0C, %rdx // host TR
vmwrite %rax, %rdx
VMSET(0x00002C02, $0x500) // host EFER
VMSET(0x00004C00, $SEL_CS64) // Host IA32_SYSENTER_CS
VMSET(0x00006C10, $0) // Host IA32_SYSENTER_ESP
VMSET(0x00006C12, $0) // Host IA32_SYSENTER_EIP
mov %cr0, %rax
VMSET(0x00006C00, %rax) // host CR0
mov %cr3, %rax
VMSET(0x00006C02, %rax) // host CR3
mov %cr4, %rax
VMSET(0x00006C04, %rax) // host CR4
VMSET(0x00006C06, $0) // host FS base
VMSET(0x00006C08, $0) // host GS base
VMSET(0x00006C0A, $ADDR_VAR_TSS64) // host TR base
VMSET(0x00006C0C, $ADDR_GDT) // host GDTR base
VMSET(0x00006C0E, $ADDR_VAR_IDT) // host IDTR base
VMSET(0x00006C14, $0) // host RSP
VMSET(0x00006C16, ADDR_VAR_VMEXIT_PTR) // host RIP
VMSET(0x00000000, $1) // VPID
VMSET(0x00000002, $0) // Posted-interrupt notification vector
//VMSET(0x00000004, $0) // EPTP index
VMSET(0x00002000, $0) // Address of I/O bitmap A
VMSET(0x00002002, $0) // Address of I/O bitmap B
VMSET(0x00002004, $0) // Address of MSR bitmaps
VMSET(0x00002006, $0) // VM-exit MSR-store address
mov $0x277, %rcx
rdmsr
shl $32, %rdx
or %rdx, %rax
VMSET(0x00002C00, %rax) // Host IA32_PAT
VMSET(0x00004004, $0) // Exception bitmap
VMSET(0x0000400A, $0) // CR3-target count
VMSET(0x0000400E, $0) // VM-exit MSR-store count
VMSET(0x00004010, $0) // VM-exit MSR-load count
VMSET(0x00004016, $0) // VM-entry interruption-information field
VMSET(0x00004014, $0) // VM-entry MSR-load count
VMSET(0x00006000, $0xffffffffffffffff) // CR0 guest/host mask
VMSET(0x00006002, $0xffffffffffffffff) // CR4 guest/host mask
VMSET(0x0000201C, $0) // EOI-exit bitmap 0
VMSET(0x0000201E, $0) // EOI-exit bitmap 1
VMSET(0x00002020, $0) // EOI-exit bitmap 2
VMSET(0x00002022, $0) // EOI-exit bitmap 3
VMSET(0x00000800, $SEL_DS64) // Guest ES selector
VMSET(0x00000802, $SEL_CS64) // Guest CS selector
VMSET(0x00000804, $SEL_DS64) // Guest SS selector
VMSET(0x00000806, $SEL_DS64) // Guest DS selector
VMSET(0x00000808, $SEL_DS64) // Guest FS selector
VMSET(0x0000080A, $SEL_DS64) // Guest GS selector
VMSET(0x0000080C, $0) // Guest LDTR selector
VMSET(0x0000080E, $SEL_TSS64) // Guest TR selector
VMSET(0x00006812, $0) // Guest LDTR base
VMSET(0x00006814, $ADDR_VAR_TSS64) // Guest TR base
VMSET(0x00006816, $ADDR_GDT) // Guest GDTR base
VMSET(0x00006818, $ADDR_VAR_IDT) // Guest IDTR base
VMSET(0x00004800, $0xfffff) // Guest ES limit
VMSET(0x00004802, $0xfffff) // Guest CS limit
VMSET(0x00004804, $0xfffff) // Guest SS limit
VMSET(0x00004806, $0xfffff) // Guest DS limit
VMSET(0x00004808, $0xfffff) // Guest FS limit
VMSET(0x0000480A, $0xfffff) // Guest GS limit
VMSET(0x0000480C, $0) // Guest LDTR limit
VMSET(0x0000480E, $0x1fff) // Guest TR limit
VMSET(0x00004810, $0x1fff) // Guest GDTR limit
VMSET(0x00004812, $0x1fff) // Guest IDTR limit
VMSET(0x00004814, $0x4093) // Guest ES access rights
VMSET(0x00004816, $0x209b) // Guest CS access rights
VMSET(0x00004818, $0x4093) // Guest SS access rights
VMSET(0x0000481A, $0x4093) // Guest DS access rights
VMSET(0x0000481C, $0x4093) // Guest FS access rights
VMSET(0x0000481E, $0x4093) // Guest GS access rights
VMSET(0x00004820, $0x82) // Guest LDTR access rights
VMSET(0x00004822, $0x8b) // Guest TR access rights
VMSET(0x0000681C, $0) // Guest RSP
VMSET(0x0000681E, $ADDR_VAR_USER_CODE) // Guest RIP
VMSET(0x00006820, $((1<<1))) // Guest RFLAGS
VMSET(0x00002806, $0x500) // Guest IA32_EFER
VMSET(0x0000280A, $0) // Guest PDPTE0
VMSET(0x0000280C, $0) // Guest PDPTE1
VMSET(0x0000280E, $0) // Guest PDPTE2
VMSET(0x00002810, $0) // Guest PDPTE3
mov %cr0, %rax
VMSET(0x00006800, %rax) // Guest CR0
mov %cr3, %rax
VMSET(0x00006802, %rax) // Guest CR3
mov %cr4, %rax
VMSET(0x00006804, %rax) // Guest CR4
// Write 1 additional random field.
mov $ADDR_VAR_VMWRITE_FLD, %rax
mov (%rax), %rdx
mov $ADDR_VAR_VMWRITE_VAL, %rax
mov (%rax), %rcx
xor %rax, %rax
vmread %rdx, %rax
xor %rcx, %rax
vmwrite %rax, %rdx
vmlaunch
mov $0x00004400, %rdx
vmread %rdx, %rax
hlt
kvm_asm64_init_vm_end:
nop
.global kvm_asm64_vm_exit, kvm_asm64_vm_exit_end
kvm_asm64_vm_exit:
.code64
//vmresume
mov $0x00004400, %rbx // VM-instruction error
vmread %rbx, %rdx
mov $0x00004402, %rbx // Exit reason
vmread %rbx, %rcx
mov $0x00006400, %rax // Exit qualification
vmread %rax, %rax
mov $0x0000681E, %rbx // Guest RIP
vmread %rbx, %rbx
hlt
kvm_asm64_vm_exit_end:
nop