CVE-2023-52639

In the Linux kernel, the following vulnerability has been resolved: KVM:
s390: vsie: fix race during shadow creation Right now it is possible to see
gmap->private being zero in kvm_s390_vsie_gmap_notifier resulting in a
crash. This is due to the fact that we add gmap->private == kvm after
creation: static int acquire_gmap_shadow(struct kvm_vcpu *vcpu, struct
vsie_page *vsie_page) { […] gmap = gmap_shadow(vcpu->arch.gmap, asce,
edat); if (IS_ERR(gmap)) return PTR_ERR(gmap); gmap->private = vcpu->kvm;
Let children inherit the private field of the parent.