KVM: VMX: Handle vmx instruction vmexits

IF a guest tries to use vmx instructions, inject a #UD to let it know the
instruction is not implemented, rather than crashing.

This prevents guest userspace from crashing the guest kernel.

Cc: stable@kernel.org
Signed-off-by: Avi Kivity <avi@redhat.com>

diff --git a/arch/x86/kvm/vmx.c b/arch/x86/kvm/vmx.c
index e770bf3..356a0ce 100644 (file)
--- a/arch/x86/kvm/vmx.c
+++ b/arch/x86/kvm/vmx.c
@@ -3012,6 +3012,12 @@ static int handle_vmcall(struct kvm_vcpu *vcpu, struct kvm_run *kvm_run)
        return 1;
 }
 
+static int handle_vmx_insn(struct kvm_vcpu *vcpu, struct kvm_run *kvm_run)
+{
+       kvm_queue_exception(vcpu, UD_VECTOR);
+       return 1;
+}
+
 static int handle_invlpg(struct kvm_vcpu *vcpu, struct kvm_run *kvm_run)
 {
        unsigned long exit_qualification = vmcs_readl(EXIT_QUALIFICATION);
@@ -3198,6 +3204,15 @@ static int (*kvm_vmx_exit_handlers[])(struct kvm_vcpu *vcpu,
        [EXIT_REASON_HLT]                     = handle_halt,
        [EXIT_REASON_INVLPG]                  = handle_invlpg,
        [EXIT_REASON_VMCALL]                  = handle_vmcall,
+       [EXIT_REASON_VMCLEAR]                 = handle_vmx_insn,
+       [EXIT_REASON_VMLAUNCH]                = handle_vmx_insn,
+       [EXIT_REASON_VMPTRLD]                 = handle_vmx_insn,
+       [EXIT_REASON_VMPTRST]                 = handle_vmx_insn,
+       [EXIT_REASON_VMREAD]                  = handle_vmx_insn,
+       [EXIT_REASON_VMRESUME]                = handle_vmx_insn,
+       [EXIT_REASON_VMWRITE]                 = handle_vmx_insn,
+       [EXIT_REASON_VMOFF]                   = handle_vmx_insn,
+       [EXIT_REASON_VMON]                    = handle_vmx_insn,
        [EXIT_REASON_TPR_BELOW_THRESHOLD]     = handle_tpr_below_threshold,
        [EXIT_REASON_APIC_ACCESS]             = handle_apic_access,
        [EXIT_REASON_WBINVD]                  = handle_wbinvd,