KVM/nVMX: Do not validate that posted_intr_desc_addr is page aligned

commit 22a7cdcae6a4a3c8974899e62851d270956f58ce upstream.

The spec only requires the posted interrupt descriptor address to be
64-bytes aligned (i.e. bits[0:5] == 0). Using page_address_valid also
forces the address to be page aligned.

Only validate that the address does not cross the maximum physical address
without enforcing a page alignment.

Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Radim Krčmář <rkrcmar@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: x86@kernel.org
Cc: kvm@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Fixes: 6de84e581c0 ("nVMX x86: check posted-interrupt descriptor addresss on vmentry of L2")
Signed-off-by: KarimAllah Ahmed <karahmed@amazon.de>
Reviewed-by: Jim Mattson <jmattson@google.com>
Reviewed-by: Krish Sadhuhan <krish.sadhukhan@oracle.com>
Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
From: Mark Mielke <mark.mielke@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/arch/x86/kvm/vmx.c b/arch/x86/kvm/vmx.c
index 3721a34..39a0e34 100644 (file)
--- a/arch/x86/kvm/vmx.c
+++ b/arch/x86/kvm/vmx.c
@@ -11733,7 +11733,7 @@ static int nested_vmx_check_apicv_controls(struct kvm_vcpu *vcpu,
            !nested_exit_intr_ack_set(vcpu) ||
            (vmcs12->posted_intr_nv & 0xff00) ||
            (vmcs12->posted_intr_desc_addr & 0x3f) ||
-           (!page_address_valid(vcpu, vmcs12->posted_intr_desc_addr))))
+           (vmcs12->posted_intr_desc_addr >> cpuid_maxphyaddr(vcpu))))
                return -EINVAL;
 
        /* tpr shadow is needed by all apicv features. */