KVM: s390: Disallow invalid bits in kvm_valid_regs and kvm_dirty_regs

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@linux.ibm.com>
Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Signed-off-by: Thomas Huth <thuth@redhat.com>
Link: https://lore.kernel.org/lkml/20190904085200.29021-2-thuth@redhat.com/
Signed-off-by: Janosch Frank <frankja@linux.ibm.com>
This commit is contained in:
Thomas Huth 2019-09-04 10:51:59 +02:00 committed by Janosch Frank
parent be6f55a60d
commit 200824f55e
2 changed files with 10 additions and 0 deletions

View File

@ -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)
/* length and alignment of the sdnx as a power of two */
#define SDNXC 8
#define SDNXL (1UL << SDNXC)

View File

@ -4008,6 +4008,10 @@ 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)) {