[PATCH 5.11 107/601] KVM: nVMX: Truncate base/index GPR value on address calc in !64-bit

Greg Kroah-Hartman
2021-05-12T17:02:33Z

From: Sean Christopherson <seanjc@google.com>

commit 82277eeed65eed6c6ee5b8f97bd978763eab148f upstream.

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>
Message-Id: <20210422022128.3464144-7-seanjc@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
arch/x86/kvm/vmx/nested.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)

--- a/arch/x86/kvm/vmx/nested.c
+++ b/arch/x86/kvm/vmx/nested.c
@@ -4639,9 +4639,9 @@ int get_vmx_mem_address(struct kvm_vcpu
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);

/*