diff options
| author | Janis Schoetterl-Glausch <scgl@linux.ibm.com> | 2022-02-11 19:22:10 +0100 |
|---|---|---|
| committer | Christian Borntraeger <borntraeger@linux.ibm.com> | 2022-02-14 16:12:57 +0100 |
| commit | e9e9feebcbc14b174fef862842f8cc9a388e1db3 (patch) | |
| tree | dee98779651470e6df4534688a926db761e7bd7e /arch/s390/kvm | |
| parent | c7ef9ebbed20b860f70cc7bece65622b570a8a93 (diff) | |
KVM: s390: Add optional storage key checking to MEMOP IOCTL
User space needs a mechanism to perform key checked accesses when
emulating instructions.
The key can be passed as an additional argument.
Having an additional argument is flexible, as user space can
pass the guest PSW's key, in order to make an access the same way the
CPU would, or pass another key if necessary.
Signed-off-by: Janis Schoetterl-Glausch <scgl@linux.ibm.com>
Reviewed-by: Claudio Imbrenda <imbrenda@linux.ibm.com>
Reviewed-by: Christian Borntraeger <borntraeger@linux.ibm.com>
Reviewed-by: Janosch Frank <frankja@linux.ibm.com>
Link: https://lore.kernel.org/r/20220211182215.2730017-6-scgl@linux.ibm.com
Signed-off-by: Christian Borntraeger <borntraeger@linux.ibm.com>
Diffstat (limited to 'arch/s390/kvm')
| -rw-r--r-- | arch/s390/kvm/kvm-s390.c | 31 |
1 files changed, 21 insertions, 10 deletions
diff --git a/arch/s390/kvm/kvm-s390.c b/arch/s390/kvm/kvm-s390.c index fdbd6c1dc709..c31b40abfa23 100644 --- a/arch/s390/kvm/kvm-s390.c +++ b/arch/s390/kvm/kvm-s390.c @@ -2359,6 +2359,11 @@ static int kvm_s390_handle_pv(struct kvm *kvm, struct kvm_pv_cmd *cmd) return r; } +static bool access_key_invalid(u8 access_key) +{ + return access_key > 0xf; +} + long kvm_arch_vm_ioctl(struct file *filp, unsigned int ioctl, unsigned long arg) { @@ -4692,17 +4697,21 @@ static long kvm_s390_guest_mem_op(struct kvm_vcpu *vcpu, void *tmpbuf = NULL; int r = 0; const u64 supported_flags = KVM_S390_MEMOP_F_INJECT_EXCEPTION - | KVM_S390_MEMOP_F_CHECK_ONLY; + | KVM_S390_MEMOP_F_CHECK_ONLY + | KVM_S390_MEMOP_F_SKEY_PROTECTION; if (mop->flags & ~supported_flags || mop->ar >= NUM_ACRS || !mop->size) return -EINVAL; - if (mop->size > MEM_OP_MAX_SIZE) return -E2BIG; - if (kvm_s390_pv_cpu_is_protected(vcpu)) return -EINVAL; - + if (mop->flags & KVM_S390_MEMOP_F_SKEY_PROTECTION) { + if (access_key_invalid(mop->key)) + return -EINVAL; + } else { + mop->key = 0; + } if (!(mop->flags & KVM_S390_MEMOP_F_CHECK_ONLY)) { tmpbuf = vmalloc(mop->size); if (!tmpbuf) @@ -4712,11 +4721,12 @@ static long kvm_s390_guest_mem_op(struct kvm_vcpu *vcpu, switch (mop->op) { case KVM_S390_MEMOP_LOGICAL_READ: if (mop->flags & KVM_S390_MEMOP_F_CHECK_ONLY) { - r = check_gva_range(vcpu, mop->gaddr, mop->ar, - mop->size, GACC_FETCH, 0); + r = check_gva_range(vcpu, mop->gaddr, mop->ar, mop->size, + GACC_FETCH, mop->key); break; } - r = read_guest(vcpu, mop->gaddr, mop->ar, tmpbuf, mop->size); + r = read_guest_with_key(vcpu, mop->gaddr, mop->ar, tmpbuf, + mop->size, mop->key); if (r == 0) { if (copy_to_user(uaddr, tmpbuf, mop->size)) r = -EFAULT; @@ -4724,15 +4734,16 @@ static long kvm_s390_guest_mem_op(struct kvm_vcpu *vcpu, break; case KVM_S390_MEMOP_LOGICAL_WRITE: if (mop->flags & KVM_S390_MEMOP_F_CHECK_ONLY) { - r = check_gva_range(vcpu, mop->gaddr, mop->ar, - mop->size, GACC_STORE, 0); + r = check_gva_range(vcpu, mop->gaddr, mop->ar, mop->size, + GACC_STORE, mop->key); break; } if (copy_from_user(tmpbuf, uaddr, mop->size)) { r = -EFAULT; break; } - r = write_guest(vcpu, mop->gaddr, mop->ar, tmpbuf, mop->size); + r = write_guest_with_key(vcpu, mop->gaddr, mop->ar, tmpbuf, + mop->size, mop->key); break; } |