diff options
| author | Felix Wilhelm | 2018-06-11 09:43:44 +0200 |
|---|---|---|
| committer | Paolo Bonzini | 2018-06-12 15:06:06 +0200 |
| commit | 727ba748e110b4de50d142edca9d6a9b7e6111d8 (patch) | |
| tree | b7573effd1110a11aac720cc38407bfdb45f651f | |
| parent | f4160e459c57646122beaea3f163b798179ea446 (diff) | |
kvm: nVMX: Enforce cpl=0 for VMX instructions
VMX instructions executed inside a L1 VM will always trigger a VM exit
even when executed with cpl 3. This means we must perform the
privilege check in software.
Fixes: 70f3aac964ae("kvm: nVMX: Remove superfluous VMX instruction fault checks")
Cc: stable@vger.kernel.org
Signed-off-by: Felix Wilhelm <fwilhelm@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
| -rw-r--r-- | arch/x86/kvm/vmx.c | 15 |
1 files changed, 13 insertions, 2 deletions
diff --git a/arch/x86/kvm/vmx.c b/arch/x86/kvm/vmx.c index 709de996f063..4bf1f9de9332 100644 --- a/arch/x86/kvm/vmx.c +++ b/arch/x86/kvm/vmx.c @@ -7905,6 +7905,12 @@ static int handle_vmon(struct kvm_vcpu *vcpu) return 1; } + /* CPL=0 must be checked manually. */ + if (vmx_get_cpl(vcpu)) { + kvm_queue_exception(vcpu, UD_VECTOR); + return 1; + } + if (vmx->nested.vmxon) { nested_vmx_failValid(vcpu, VMXERR_VMXON_IN_VMX_ROOT_OPERATION); return kvm_skip_emulated_instruction(vcpu); @@ -7964,6 +7970,11 @@ static int handle_vmon(struct kvm_vcpu *vcpu) */ static int nested_vmx_check_permission(struct kvm_vcpu *vcpu) { + if (vmx_get_cpl(vcpu)) { + kvm_queue_exception(vcpu, UD_VECTOR); + return 0; + } + if (!to_vmx(vcpu)->nested.vmxon) { kvm_queue_exception(vcpu, UD_VECTOR); return 0; @@ -8283,7 +8294,7 @@ static int handle_vmread(struct kvm_vcpu *vcpu) if (get_vmx_mem_address(vcpu, exit_qualification, vmx_instruction_info, true, &gva)) return 1; - /* _system ok, as hardware has verified cpl=0 */ + /* _system ok, nested_vmx_check_permission has verified cpl=0 */ kvm_write_guest_virt_system(&vcpu->arch.emulate_ctxt, gva, &field_value, (is_long_mode(vcpu) ? 8 : 4), NULL); } @@ -8448,7 +8459,7 @@ static int handle_vmptrst(struct kvm_vcpu *vcpu) if (get_vmx_mem_address(vcpu, exit_qualification, vmx_instruction_info, true, &vmcs_gva)) return 1; - /* ok to use *_system, as hardware has verified cpl=0 */ + /* *_system ok, nested_vmx_check_permission has verified cpl=0 */ if (kvm_write_guest_virt_system(&vcpu->arch.emulate_ctxt, vmcs_gva, (void *)&to_vmx(vcpu)->nested.current_vmptr, sizeof(u64), &e)) { |