KVM: VMX: Don't allow uninhibited access to EFER on i386
vmx_set_msr() does not allow i386 guests to touch EFER, but they can still
do so through the default: label in the switch. If they set EFER_LME, they
can oops the host.
Fix by having EFER access through the normal channel (which will check for
EFER_LME) even on i386.
Reported-and-tested-by: Benjamin Gilbert <bgilbert@cs.cmu.edu>
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 48063a0..bb48133 100644
--- a/arch/x86/kvm/vmx.c
+++ b/arch/x86/kvm/vmx.c
@@ -936,11 +936,11 @@
int ret = 0;
switch (msr_index) {
-#ifdef CONFIG_X86_64
case MSR_EFER:
vmx_load_host_state(vmx);
ret = kvm_set_msr_common(vcpu, msr_index, data);
break;
+#ifdef CONFIG_X86_64
case MSR_FS_BASE:
vmcs_writel(GUEST_FS_BASE, data);
break;
