diff options
| author |   Sean Christopherson <seanjc@google.com> | 2021-06-09 16:42:34 -0700 |
|---|---|---|
| committer |   Paolo Bonzini <pbonzini@redhat.com> | 2021-06-17 13:09:54 -0400 |
| commit | 546e8398bc0c7f75f696a24a997d2befeb632154 (patch) | |
| tree | 4490e2fcf3ddefefb07f5f1445dc0c538e2a1533 /arch/x86/kvm/vmx/nested.c | |
| parent | KVM: x86: Drop pointless @reset_roots from kvm_init_mmu() (diff) | |
| download | linux-dev-546e8398bc0c7f75f696a24a997d2befeb632154.tar.xz linux-dev-546e8398bc0c7f75f696a24a997d2befeb632154.zip | |
KVM: nVMX: WARN if subtly-impossible VMFUNC conditions occur
WARN and inject #UD when emulating VMFUNC for L2 if the function is
out-of-bounds or if VMFUNC is not enabled in vmcs12. Neither condition
should occur in practice, as the CPU is supposed to prioritize the #UD
over VM-Exit for out-of-bounds input and KVM is supposed to enable
VMFUNC in vmcs02 if and only if it's enabled in vmcs12, but neither of
those dependencies is obvious.
Signed-off-by: Sean Christopherson <seanjc@google.com>
Message-Id: <20210609234235.1244004-15-seanjc@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Diffstat (limited to '')
| -rw-r--r-- | arch/x86/kvm/vmx/nested.c | 10 |
1 files changed, 10 insertions, 0 deletions
diff --git a/arch/x86/kvm/vmx/nested.c b/arch/x86/kvm/vmx/nested.c index aba11422500c..6342bb4c46b3 100644 --- a/arch/x86/kvm/vmx/nested.c +++ b/arch/x86/kvm/vmx/nested.c @@ -5552,6 +5552,16 @@ static int handle_vmfunc(struct kvm_vcpu *vcpu) } vmcs12 = get_vmcs12(vcpu); + + /* + * #UD on out-of-bounds function has priority over VM-Exit, and VMFUNC + * is enabled in vmcs02 if and only if it's enabled in vmcs12. + */ + if (WARN_ON_ONCE((function > 63) || !nested_cpu_has_vmfunc(vmcs12))) { + kvm_queue_exception(vcpu, UD_VECTOR); + return 1; + } + if (!(vmcs12->vm_function_control & BIT_ULL(function))) goto fail; |