On 26.04.19 10:56, Pierre Morel wrote:
> When the guest do not have AP instructions nor Key management
> we should return without shadowing the CRYCB.
>
> We did not check correctly in the past.
>
> Fixes: b10bd9a256ae ("s390: vsie: Use effective CRYCBD.31 to check CRYCBD
> validity")
> Fixes: 6ee74098201b ("KVM: s390: vsie: allow CRYCB FORMAT-0")
>
> Signed-off-by: Pierre Morel <pmorel@xxxxxxxxxxxxx>
> Reported-by: Christian Borntraeger <borntraeger@xxxxxxxxxx>
Tested-by: Christian Borntraeger <borntraeger@xxxxxxxxxx>
Reviewed-by: Christian Borntraeger <borntraeger@xxxxxxxxxx>
> ---
> arch/s390/kvm/vsie.c | 6 ++++--
> 1 file changed, 4 insertions(+), 2 deletions(-)
>
> diff --git a/arch/s390/kvm/vsie.c b/arch/s390/kvm/vsie.c
> index c6983d9..ac411e9 100644
> --- a/arch/s390/kvm/vsie.c
> +++ b/arch/s390/kvm/vsie.c
> @@ -290,6 +290,7 @@ static int shadow_crycb(struct kvm_vcpu *vcpu, struct vsie_page *vsie_page)
> u8 ecb3_flags;
> u32 ecd_flags;
> int apie_h;
> + int apie_s;
> int key_msk = test_kvm_facility(vcpu->kvm, 76);
> int fmt_o = crycbd_o & CRYCB_FORMAT_MASK;
> int fmt_h = vcpu->arch.sie_block->crycbd & CRYCB_FORMAT_MASK;
> @@ -298,7 +299,8 @@ static int shadow_crycb(struct kvm_vcpu *vcpu, struct vsie_page *vsie_page)
> scb_s->crycbd = 0;
>
> apie_h = vcpu->arch.sie_block->eca & ECA_APIE;
> - if (!apie_h && (!key_msk || fmt_o == CRYCB_FORMAT0))
> + apie_s = apie_h & scb_o->eca;
> + if (!apie_s && (!key_msk || (fmt_o == CRYCB_FORMAT0)))
> return 0;
>
> if (!crycb_addr)
> @@ -309,7 +311,7 @@ static int shadow_crycb(struct kvm_vcpu *vcpu, struct vsie_page *vsie_page)
> ((crycb_addr + 128) & PAGE_MASK))
> return set_validity_icpt(scb_s, 0x003CU);
>
> - if (apie_h && (scb_o->eca & ECA_APIE)) {
> + if (apie_s) {
> ret = setup_apcb(vcpu, &vsie_page->crycb, crycb_addr,
> vcpu->kvm->arch.crypto.crycb,
> fmt_o, fmt_h);
>
