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
|
#
# requires: arch=amd64 -threaded
#
r0 = openat$kvm(0, &AUTO='/dev/kvm\x00', 0x0, 0x0)
r1 = ioctl$KVM_CREATE_VM(r0, AUTO, 0x0)
r2 = syz_kvm_setup_syzos_vm$x86(r1, &(0x7f0000c00000/0x400000)=nil)
# Test AMD Nested Intercepts: The RDTSC Liberation
#
# 1. L1 Setup:
# - SYZOS initializes VMCB with ALL intercepts enabled.
# - We call SET_INTERCEPT to *CLEAR* the RDTSC intercept.
# - Offset: 0xC (Control Vector 1)
# - Bit: 14 (0x4000) = RDTSC
# - Action: 0 (Clear/Disable)
#
# 2. L2 Payload:
# - "rdtsc" (0x0f 0x31)
# - "hlt" (0xf4)
#
# 3. Execution Flow:
# - If RDTSC is intercepted: Exit Reason = RDTSC (0x4).
# - If RDTSC is native: executes RDTSC -> executes HLT -> Exit Reason = HLT (0x1).
#
r3 = syz_kvm_add_vcpu$x86(r2, &AUTO={0x0, &AUTO=[@enable_nested={AUTO, AUTO, 0x0}, @nested_create_vm={AUTO, AUTO, 0x0}, @nested_amd_set_intercept={AUTO, AUTO, {0x0, 0xC, 0x4000, 0x0}}, @nested_load_code={AUTO, AUTO, {0x0, "0f31f4"}}, @nested_vmlaunch={AUTO, AUTO, 0x0}], AUTO})
r4 = ioctl$KVM_GET_VCPU_MMAP_SIZE(r0, AUTO)
r5 = mmap$KVM_VCPU(&(0x7f0000009000/0x1000)=nil, r4, 0x3, 0x1, r3, 0x0)
# Run the VCPU.
# Expectation: Success (Native Execution) -> HLT Exit.
# Code: 0xe2e20001 (SYZOS_NESTED_EXIT_REASON_HLT)
#
ioctl$KVM_RUN(r3, AUTO, 0x0)
syz_kvm_assert_syzos_uexit$x86(r3, r5, 0xe2e20001)
# Cleanup
#
ioctl$KVM_RUN(r3, AUTO, 0x0)
syz_kvm_assert_syzos_uexit$x86(r3, r5, 0xffffffffffffffff)
|
