diff --git a/virt/kvm/dirty_ring.c b/virt/kvm/dirty_ring.c
index d6fabf238032..cb7b167ea82c 100644
--- a/virt/kvm/dirty_ring.c
+++ b/virt/kvm/dirty_ring.c
@@ -49,7 +49,8 @@ static void kvm_reset_dirty_gfn(struct kvm *kvm, u32 slot, u64 offset, u64 mask)
 
 	memslot = id_to_memslot(__kvm_memslots(kvm, as_id), id);
 
-	if (!memslot || (offset + __fls(mask)) >= memslot->npages)
+	if (!memslot || offset >= memslot->npages ||
+	    offset + __fls(mask) >= memslot->npages)
 		return;
 
 	KVM_MMU_LOCK(kvm);