From 4e2c7f7cbc27418f9a290399b986c1b85ff93b90 Mon Sep 17 00:00:00 2001 From: Christian Borntraeger Date: Wed, 5 Aug 2026 13:04:49 +0200 Subject: KVM: s390: Zero initialize data structures for inject_pfault_token __kvm_inject_pfault_token() only sets .type and .u.ext.ext_params2 of the on-stack struct kvm_s390_irq but the full ext substructure is copied into the cpu local variable on inject. ext_params and pad contain stale stack values. Interrupt delivery only uses ext_params2, so nothing leaks to the guest, but a host user can use the migration ioctls to get to the data. Fix by zero-initializing the irq struct. Do the same for the inti data structure. Fixes: 383d0b050106 ("KVM: s390: handle pending local interrupts via bitmap") Cc: stable@vger.kernel.org Signed-off-by: Christian Borntraeger Reviewed-by: Matthew Rosato Reviewed-by: Claudio Imbrenda Signed-off-by: Claudio Imbrenda Message-ID: <20260805110455.7200-3-borntraeger@linux.ibm.com> --- arch/s390/kvm/kvm-s390.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/arch/s390/kvm/kvm-s390.c b/arch/s390/kvm/kvm-s390.c index 518a69c55e85..611dcb534210 100644 --- a/arch/s390/kvm/kvm-s390.c +++ b/arch/s390/kvm/kvm-s390.c @@ -4474,8 +4474,8 @@ int kvm_s390_try_set_tod_clock(struct kvm *kvm, const struct kvm_s390_vm_tod_clo static void __kvm_inject_pfault_token(struct kvm_vcpu *vcpu, bool start_token, unsigned long token) { - struct kvm_s390_interrupt inti; - struct kvm_s390_irq irq; + struct kvm_s390_interrupt inti = {}; + struct kvm_s390_irq irq = {}; struct kvm_s390_interrupt_info *inti_mem = NULL; int ret = 0; -- cgit v1.2.3