FAILED: patch "[PATCH] KVM: x86: Avoid theoretical NULL pointer dereference in" failed to apply to 5.4-stable tree

The patch below does not apply to the 5.4-stable tree.
If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to <[email protected]>.

thanks,

greg k-h

------------------ original commit in Linus's tree ------------------

From 00b5f37189d24ac3ed46cb7f11742094778c46ce Mon Sep 17 00:00:00 2001
From: Vitaly Kuznetsov <[email protected]>
Date: Fri, 25 Mar 2022 14:21:39 +0100
Subject: [PATCH] KVM: x86: Avoid theoretical NULL pointer dereference in
kvm_irq_delivery_to_apic_fast()

When kvm_irq_delivery_to_apic_fast() is called with APIC_DEST_SELF shorthand, 'src' must not be NULL. Crash the VM with KVM_BUG_ON() instead of crashing the host.

Message-Id: <[email protected]>

index 80a2020c4db4..66b0eb0bda94 100644
@@ -1024,6 +1024,10 @@ bool kvm_irq_delivery_to_apic_fast(struct kvm *kvm, struct kvm_lapic *src,
 	*r = -1;
 
 	if (irq->shorthand == APIC_DEST_SELF) {
+		if (KVM_BUG_ON(!src, kvm)) {
+			*r = 0;
+			return true;
+		}
 		*r = kvm_apic_set_irq(src->vcpu, irq, dest_map);
 		return true;
 	}