--- /dev/null
+From foo@baz Mon Aug 16 09:26:03 PM CEST 2021
+From: Paolo Bonzini <pbonzini@redhat.com>
+Date: Mon, 16 Aug 2021 16:02:32 +0200
+Subject: KVM: nSVM: avoid picking up unsupported bits from L2 in int_ctl (CVE-2021-3653)
+To: linux-kernel@vger.kernel.org, kvm@vger.kernel.org
+Cc: stable@vger.kernel.org, Maxim Levitsky <mlevitsk@redhat.com>
+Message-ID: <20210816140240.11399-4-pbonzini@redhat.com>
+
+From: Maxim Levitsky <mlevitsk@redhat.com>
+
+[ upstream commit 0f923e07124df069ba68d8bb12324398f4b6b709 ]
+
+* Invert the mask of bits that we pick from L2 in
+ nested_vmcb02_prepare_control
+
+* Invert and explicitly use VIRQ related bits bitmask in svm_clear_vintr
+
+This fixes a security issue that allowed a malicious L1 to run L2 with
+AVIC enabled, which allowed the L2 to exploit the uninitialized and enabled
+AVIC to read/write the host physical memory at some offsets.
+
+Fixes: 3d6368ef580a ("KVM: SVM: Add VMRUN handler")
+Signed-off-by: Maxim Levitsky <mlevitsk@redhat.com>
+Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
+Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
+---
+ arch/x86/include/asm/svm.h | 2 ++
+ arch/x86/kvm/svm.c | 6 +++++-
+ 2 files changed, 7 insertions(+), 1 deletion(-)
+
+--- a/arch/x86/include/asm/svm.h
++++ b/arch/x86/include/asm/svm.h
+@@ -113,6 +113,8 @@ struct __attribute__ ((__packed__)) vmcb
+ #define V_IGN_TPR_SHIFT 20
+ #define V_IGN_TPR_MASK (1 << V_IGN_TPR_SHIFT)
+
++#define V_IRQ_INJECTION_BITS_MASK (V_IRQ_MASK | V_INTR_PRIO_MASK | V_IGN_TPR_MASK)
++
+ #define V_INTR_MASKING_SHIFT 24
+ #define V_INTR_MASKING_MASK (1 << V_INTR_MASKING_SHIFT)
+
+--- a/arch/x86/kvm/svm.c
++++ b/arch/x86/kvm/svm.c
+@@ -3048,7 +3048,11 @@ static bool nested_svm_vmrun(struct vcpu
+ svm->nested.intercept = nested_vmcb->control.intercept;
+
+ svm_flush_tlb(&svm->vcpu);
+- svm->vmcb->control.int_ctl = nested_vmcb->control.int_ctl | V_INTR_MASKING_MASK;
++ svm->vmcb->control.int_ctl = nested_vmcb->control.int_ctl &
++ (V_TPR_MASK | V_IRQ_INJECTION_BITS_MASK);
++
++ svm->vmcb->control.int_ctl |= V_INTR_MASKING_MASK;
++
+ if (nested_vmcb->control.int_ctl & V_INTR_MASKING_MASK)
+ svm->vcpu.arch.hflags |= HF_VINTR_MASK;
+ else