Replace kzalloc() followed by copy_from_user() with memdup_user() to improve and simplify svm_set_nested_state(). Return early if an error occurs instead of trying to allocate memory for 'save' when memory allocation for 'ctl' already failed. Signed-off-by: Thorsten Blum --- arch/x86/kvm/svm/nested.c | 20 +++++++++----------- 1 file changed, 9 insertions(+), 11 deletions(-) diff --git a/arch/x86/kvm/svm/nested.c b/arch/x86/kvm/svm/nested.c index b7fd2e869998..826473f2d7c7 100644 --- a/arch/x86/kvm/svm/nested.c +++ b/arch/x86/kvm/svm/nested.c @@ -1798,17 +1798,15 @@ static int svm_set_nested_state(struct kvm_vcpu *vcpu, if (kvm_state->size < sizeof(*kvm_state) + KVM_STATE_NESTED_SVM_VMCB_SIZE) return -EINVAL; - ret = -ENOMEM; - ctl = kzalloc(sizeof(*ctl), GFP_KERNEL); - save = kzalloc(sizeof(*save), GFP_KERNEL); - if (!ctl || !save) - goto out_free; - - ret = -EFAULT; - if (copy_from_user(ctl, &user_vmcb->control, sizeof(*ctl))) - goto out_free; - if (copy_from_user(save, &user_vmcb->save, sizeof(*save))) - goto out_free; + ctl = memdup_user(&user_vmcb->control, sizeof(*ctl)); + if (IS_ERR(ctl)) + return PTR_ERR(ctl); + + save = memdup_user(&user_vmcb->save, sizeof(*save)); + if (IS_ERR(save)) { + kfree(ctl); + return PTR_ERR(save); + } ret = -EINVAL; __nested_copy_vmcb_control_to_cache(vcpu, &ctl_cached, ctl); -- 2.51.0