| Message ID | 20210422022128.3464144-6-seanjc@google.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | KVM: x86: Fixes for (benign?) truncation bugs | expand |
diff --git a/arch/x86/kvm/vmx/nested.c b/arch/x86/kvm/vmx/nested.c index 8b111682fe5c..0e580305a1ee 100644 --- a/arch/x86/kvm/vmx/nested.c +++ b/arch/x86/kvm/vmx/nested.c @@ -5743,7 +5743,7 @@ static bool nested_vmx_exit_handled_vmcs_access(struct kvm_vcpu *vcpu, /* Decode instruction info and find the field to access */ vmx_instruction_info = vmcs_read32(VMX_INSTRUCTION_INFO); - field = kvm_register_read(vcpu, (((vmx_instruction_info) >> 28) & 0xf)); + field = kvm_register_readl(vcpu, (((vmx_instruction_info) >> 28) & 0xf)); /* Out-of-range fields always cause a VM exit from L2 to L1 */ if (field >> 15)
Drop bits 63:32 of the VMCS field encoding when checking for a nested VM-Exit on VMREAD/VMWRITE in !64-bit mode. VMREAD and VMWRITE always use 32-bit operands outside of 64-bit mode. The actual emulation of VMREAD/VMWRITE does the right thing, this bug is purely limited to incorrectly causing a nested VM-Exit if a GPR happens to have bits 63:32 set outside of 64-bit mode. Fixes: a7cde481b6e8 ("KVM: nVMX: Do not forward VMREAD/VMWRITE VMExits to L1 if required so by vmcs12 vmread/vmwrite bitmaps") Cc: stable@vger.kernel.org Signed-off-by: Sean Christopherson <seanjc@google.com> --- arch/x86/kvm/vmx/nested.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)