On 04.09.19 10:51, Thomas Huth wrote: > If unknown bits are set in kvm_valid_regs or kvm_dirty_regs, this > clearly indicates that something went wrong in the KVM userspace > application. The x86 variant of KVM already contains a check for > bad bits, so let's do the same on s390x now, too. > > Reviewed-by: Janosch Frank <frankja@xxxxxxxxxxxxx> > Reviewed-by: Christian Borntraeger <borntraeger@xxxxxxxxxx> > Reviewed-by: Cornelia Huck <cohuck@xxxxxxxxxx> > Signed-off-by: Thomas Huth <thuth@xxxxxxxxxx> > --- > arch/s390/include/uapi/asm/kvm.h | 6 ++++++ > arch/s390/kvm/kvm-s390.c | 4 ++++ > 2 files changed, 10 insertions(+) > > diff --git a/arch/s390/include/uapi/asm/kvm.h b/arch/s390/include/uapi/asm/kvm.h > index 47104e5b47fd..436ec7636927 100644 > --- a/arch/s390/include/uapi/asm/kvm.h > +++ b/arch/s390/include/uapi/asm/kvm.h > @@ -231,6 +231,12 @@ struct kvm_guest_debug_arch { > #define KVM_SYNC_GSCB (1UL << 9) > #define KVM_SYNC_BPBC (1UL << 10) > #define KVM_SYNC_ETOKEN (1UL << 11) > + > +#define KVM_SYNC_S390_VALID_FIELDS \ > + (KVM_SYNC_PREFIX | KVM_SYNC_GPRS | KVM_SYNC_ACRS | KVM_SYNC_CRS | \ > + KVM_SYNC_ARCH0 | KVM_SYNC_PFAULT | KVM_SYNC_VRS | KVM_SYNC_RICCB | \ > + KVM_SYNC_FPRS | KVM_SYNC_GSCB | KVM_SYNC_BPBC | KVM_SYNC_ETOKEN) > + We didn't care about the S390 for the actual flags, why care now? > /* length and alignment of the sdnx as a power of two */ > #define SDNXC 8 > #define SDNXL (1UL << SDNXC) > diff --git a/arch/s390/kvm/kvm-s390.c b/arch/s390/kvm/kvm-s390.c > index 49d7722229ae..a7d7dedfe527 100644 > --- a/arch/s390/kvm/kvm-s390.c > +++ b/arch/s390/kvm/kvm-s390.c > @@ -3998,6 +3998,10 @@ int kvm_arch_vcpu_ioctl_run(struct kvm_vcpu *vcpu, struct kvm_run *kvm_run) > if (kvm_run->immediate_exit) > return -EINTR; > > + if (kvm_run->kvm_valid_regs & ~KVM_SYNC_S390_VALID_FIELDS || > + kvm_run->kvm_dirty_regs & ~KVM_SYNC_S390_VALID_FIELDS) > + return -EINVAL; > + > vcpu_load(vcpu); > > if (guestdbg_exit_pending(vcpu)) { > Reviewed-by: David Hildenbrand <david@xxxxxxxxxx> -- Thanks, David / dhildenb