From: Janis Schoetterl-Glausch <scgl@xxxxxxxxxxxxx> The vcpu and vm mem_op ioctl implementations share some functionality. Move argument checking into a function and call it from both implementations. This allows code reuse in case of additional future mem_op operations. Suggested-by: Janosch Frank <frankja@xxxxxxxxxxxxx> Signed-off-by: Janis Schoetterl-Glausch <scgl@xxxxxxxxxxxxx> Reviewed-by: Janosch Frank <frankja@xxxxxxxxxxxxx> Link: https://lore.kernel.org/r/20230206164602.138068-9-scgl@xxxxxxxxxxxxx Message-Id: <20230206164602.138068-9-scgl@xxxxxxxxxxxxx> Signed-off-by: Janosch Frank <frankja@xxxxxxxxxxxxx> --- arch/s390/kvm/kvm-s390.c | 52 +++++++++++++++++++--------------------- 1 file changed, 24 insertions(+), 28 deletions(-) diff --git a/arch/s390/kvm/kvm-s390.c b/arch/s390/kvm/kvm-s390.c index cb72f9a09fb3..9645015f5921 100644 --- a/arch/s390/kvm/kvm-s390.c +++ b/arch/s390/kvm/kvm-s390.c @@ -2764,24 +2764,32 @@ static int kvm_s390_handle_pv(struct kvm *kvm, struct kvm_pv_cmd *cmd) return r; } -static bool access_key_invalid(u8 access_key) +static int mem_op_validate_common(struct kvm_s390_mem_op *mop, u64 supported_flags) { - return access_key > 0xf; + if (mop->flags & ~supported_flags || !mop->size) + return -EINVAL; + if (mop->size > MEM_OP_MAX_SIZE) + return -E2BIG; + if (mop->flags & KVM_S390_MEMOP_F_SKEY_PROTECTION) { + if (mop->key > 0xf) + return -EINVAL; + } else { + mop->key = 0; + } + return 0; } static int kvm_s390_vm_mem_op(struct kvm *kvm, struct kvm_s390_mem_op *mop) { void __user *uaddr = (void __user *)mop->buf; - u64 supported_flags; void *tmpbuf = NULL; int r, srcu_idx; - supported_flags = KVM_S390_MEMOP_F_SKEY_PROTECTION - | KVM_S390_MEMOP_F_CHECK_ONLY; - if (mop->flags & ~supported_flags || !mop->size) - return -EINVAL; - if (mop->size > MEM_OP_MAX_SIZE) - return -E2BIG; + r = mem_op_validate_common(mop, KVM_S390_MEMOP_F_SKEY_PROTECTION | + KVM_S390_MEMOP_F_CHECK_ONLY); + if (r) + return r; + /* * This is technically a heuristic only, if the kvm->lock is not * taken, it is not guaranteed that the vm is/remains non-protected. @@ -2793,12 +2801,6 @@ static int kvm_s390_vm_mem_op(struct kvm *kvm, struct kvm_s390_mem_op *mop) */ if (kvm_s390_pv_get_handle(kvm)) 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) @@ -5250,23 +5252,17 @@ static long kvm_s390_vcpu_mem_op(struct kvm_vcpu *vcpu, { void __user *uaddr = (void __user *)mop->buf; 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_SKEY_PROTECTION; + int r; - if (mop->flags & ~supported_flags || mop->ar >= NUM_ACRS || !mop->size) + r = mem_op_validate_common(mop, KVM_S390_MEMOP_F_INJECT_EXCEPTION | + KVM_S390_MEMOP_F_CHECK_ONLY | + KVM_S390_MEMOP_F_SKEY_PROTECTION); + if (r) + return r; + if (mop->ar >= NUM_ACRS) 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) -- 2.39.1