On Wed, Jul 10, 2019 at 08:13:06PM +0000, Singh, Brijesh wrote:
> The command is used for copying the incoming buffer into the
> SEV guest memory space.
...
> +static int sev_receive_update_data(struct kvm *kvm, struct kvm_sev_cmd *argp)
> +{
> + struct kvm_sev_info *sev = &to_kvm_svm(kvm)->sev_info;
> + struct kvm_sev_receive_update_data params;
> + struct sev_data_receive_update_data *data;
> + void *hdr = NULL, *trans = NULL;
> + struct page **guest_page;
> + unsigned long n;
> + int ret, offset;
> +
> + if (!sev_guest(kvm))
> + return -EINVAL;
> +
> + if (copy_from_user(¶ms, (void __user *)(uintptr_t)argp->data,
> + sizeof(struct kvm_sev_receive_update_data)))
> + return -EFAULT;
> +
> + if (!params.hdr_uaddr || !params.hdr_len ||
> + !params.guest_uaddr || !params.guest_len ||
> + !params.trans_uaddr || !params.trans_len)
> + return -EINVAL;
> +
> + /* Check if we are crossing the page boundry */
WARNING: 'boundry' may be misspelled - perhaps 'boundary'?
> + offset = params.guest_uaddr & (PAGE_SIZE - 1);
> + if ((params.guest_len + offset > PAGE_SIZE))
> + return -EINVAL;
> +
> + data = kzalloc(sizeof(*data), GFP_KERNEL);
> + if (!data)
> + return -ENOMEM;
> +
> + hdr = psp_copy_user_blob(params.hdr_uaddr, params.hdr_len);
> + if (IS_ERR(hdr)) {
> + ret = PTR_ERR(hdr);
> + goto e_free;
> + }
> +
> + data->hdr_address = __psp_pa(hdr);
> + data->hdr_len = params.hdr_len;
> +
> + trans = psp_copy_user_blob(params.trans_uaddr, params.trans_len);
> + if (IS_ERR(trans)) {
> + ret = PTR_ERR(trans);
> + goto e_free;
> + }
> +
> + data->trans_address = __psp_pa(trans);
> + data->trans_len = params.trans_len;
> +
> + /* Pin guest memory */
> + ret = -EFAULT;
> + guest_page = sev_pin_memory(kvm, params.guest_uaddr & PAGE_MASK,
> + PAGE_SIZE, &n, 0);
> + if (!guest_page)
> + goto e_free;
> +
> + /* The RECEIVE_UPDATE_DATA command requires C-bit to be always set. */
> + data->guest_address = (page_to_pfn(guest_page[0]) << PAGE_SHIFT) + offset;
> + data->guest_address |= sev_me_mask;
> + data->guest_len = params.guest_len;
> +
> + data->handle = sev->handle;
> + ret = sev_issue_cmd(kvm, SEV_CMD_RECEIVE_UPDATE_DATA, data, &argp->error);
> +
> + sev_unpin_memory(kvm, guest_page, n);
> +e_free:
> + kfree(data);
> + kfree(hdr);
> + kfree(trans);
Pls add separate labels so that you don't have to init function-local
vars above to NULL.
--
Regards/Gruss,
Boris.
SUSE Software Solutions Germany GmbH, GF: Felix Imendörffer, HRB 247165, AG München
