[PATCH v2 6/9] KVM: nVMX: Truncate base/index GPR value on address calc in !64-bit

Sean Christopherson
2021-04-22T02:21:49Z

Drop bits 63:32 of the base and/or index GPRs when calculating the
effective address of a VMX instruction memory operand. Outside of 64-bit
mode, memory encodings are strictly limited to E*X and below.

Fixes: 064aea774768 ("KVM: nVMX: Decoding memory operands of VMX instructions")
Cc: stable@vger.kernel.org
Signed-off-by: Sean Christopherson <seanjc@google.com>
---
arch/x86/kvm/vmx/nested.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/arch/x86/kvm/vmx/nested.c b/arch/x86/kvm/vmx/nested.c
index 0e580305a1ee..4daf1ff45221 100644
--- a/arch/x86/kvm/vmx/nested.c
+++ b/arch/x86/kvm/vmx/nested.c
@@ -4617,9 +4617,9 @@ int get_vmx_mem_address(struct kvm_vcpu *vcpu, unsigned long exit_qualification,
else if (addr_size == 0)
off = (gva_t)sign_extend64(off, 15);
if (base_is_valid)
- off += kvm_register_read(vcpu, base_reg);
+ off += kvm_register_readl(vcpu, base_reg);
if (index_is_valid)
- off += kvm_register_read(vcpu, index_reg) << scaling;
+ off += kvm_register_readl(vcpu, index_reg) << scaling;
vmx_get_segment(vcpu, &s, seg_reg);

/*