KVM: SVM: CSV: Add KVM_CSV3_RECEIVE_ENCRYPT_DATA command

hygon inclusion
category: feature
CVE: NA

---------------------------

The command is used for copying the incoming buffer into the
CSV3 guest's private memory.

Signed-off-by: Xin Jiang <jiangxin@hygon.cn>
Signed-off-by: hanliyang <hanliyang@hygon.cn>

arch/x86/kvm/svm/csv.c

@@ -1546,6 +1546,125 @@ static int csv3_send_encrypt_context(struct kvm *kvm, struct kvm_sev_cmd *argp)
 	return ret;
 }
 
+static int csv3_receive_encrypt_data(struct kvm *kvm, struct kvm_sev_cmd *argp)
+{
+	struct kvm_sev_info *sev = &to_kvm_svm(kvm)->sev_info;
+	struct kvm_csv_info *csv = &to_kvm_svm_csv(kvm)->csv_info;
+	struct csv3_data_receive_encrypt_data data;
+	struct kvm_csv3_receive_encrypt_data params;
+	void *hdr;
+	void *trans_data;
+	struct trans_paddr_block *trans_block;
+	struct guest_paddr_block *guest_block;
+	unsigned long pfn;
+	int i;
+	u32 offset;
+	int ret = 0;
+
+	if (!csv3_guest(kvm))
+		return -ENOTTY;
+
+	if (unlikely(list_empty(&csv->smr_list))) {
+		/* Allocate all the guest memory from CMA */
+		ret = csv3_set_guest_private_memory(kvm);
+		if (ret)
+			goto exit;
+	}
+
+	if (copy_from_user(&params, (void __user *)(uintptr_t)argp->data,
+			   sizeof(params)))
+		return -EFAULT;
+
+	if (!params.hdr_uaddr || !params.hdr_len ||
+	    !params.guest_addr_data || !params.guest_addr_len ||
+	    !params.trans_uaddr || !params.trans_len)
+		return -EINVAL;
+
+	if (params.guest_addr_len > sizeof(*guest_block))
+		return -EINVAL;
+
+	if (params.trans_len > ARRAY_SIZE(trans_block->trans_paddr) * PAGE_SIZE)
+		return -EINVAL;
+
+	/* allocate memory for header and transport buffer */
+	hdr = kzalloc(params.hdr_len, GFP_KERNEL_ACCOUNT);
+	if (!hdr) {
+		ret = -ENOMEM;
+		goto exit;
+	}
+
+	if (copy_from_user(hdr,
+			   (void __user *)(uintptr_t)params.hdr_uaddr,
+			   params.hdr_len)) {
+		ret = -EFAULT;
+		goto e_free_hdr;
+	}
+
+	guest_block = kzalloc(sizeof(*guest_block), GFP_KERNEL_ACCOUNT);
+	if (!guest_block) {
+		ret = -ENOMEM;
+		goto e_free_hdr;
+	}
+
+	if (copy_from_user(guest_block,
+			   (void __user *)(uintptr_t)params.guest_addr_data,
+			   params.guest_addr_len)) {
+		ret = -EFAULT;
+		goto e_free_guest_block;
+	}
+
+	trans_block = kzalloc(sizeof(*trans_block), GFP_KERNEL_ACCOUNT);
+	if (!trans_block) {
+		ret = -ENOMEM;
+		goto e_free_guest_block;
+	}
+	trans_data = vzalloc(params.trans_len);
+	if (!trans_data) {
+		ret = -ENOMEM;
+		goto e_free_trans_block;
+	}
+
+	if (copy_from_user(trans_data,
+			   (void __user *)(uintptr_t)params.trans_uaddr,
+			   params.trans_len)) {
+		ret = -EFAULT;
+		goto e_free_trans_data;
+	}
+
+	for (offset = 0, i = 0; offset < params.trans_len; offset += PAGE_SIZE) {
+		pfn = vmalloc_to_pfn(offset + trans_data);
+		trans_block->trans_paddr[i] = __sme_set(pfn_to_hpa(pfn));
+		i++;
+	}
+
+	memset(&data, 0, sizeof(data));
+	data.hdr_address = __psp_pa(hdr);
+	data.hdr_len = params.hdr_len;
+	data.trans_block = __psp_pa(trans_block);
+	data.trans_len = params.trans_len;
+	data.guest_block = __psp_pa(guest_block);
+	data.guest_len = params.guest_addr_len;
+	data.handle = sev->handle;
+
+	clflush_cache_range(hdr, params.hdr_len);
+	clflush_cache_range(trans_data, params.trans_len);
+	clflush_cache_range(trans_block, PAGE_SIZE);
+	clflush_cache_range(guest_block, PAGE_SIZE);
+	ret = hygon_kvm_hooks.sev_issue_cmd(kvm, CSV3_CMD_RECEIVE_ENCRYPT_DATA,
+					    &data, &argp->error);
+
+e_free_trans_data:
+	vfree(trans_data);
+e_free_trans_block:
+	kfree(trans_block);
+e_free_guest_block:
+	kfree(guest_block);
+e_free_hdr:
+	kfree(hdr);
+exit:
+	return ret;
+}
+
 static void csv3_mark_page_dirty(struct kvm_vcpu *vcpu, gva_t gpa,
 				 unsigned long npages)
 {
@@ -2024,6 +2143,9 @@ static int csv_mem_enc_ioctl(struct kvm *kvm, void __user *argp)
 	case KVM_CSV3_SEND_ENCRYPT_CONTEXT:
 		r = csv3_send_encrypt_context(kvm, &sev_cmd);
 		break;
+	case KVM_CSV3_RECEIVE_ENCRYPT_DATA:
+		r = csv3_receive_encrypt_data(kvm, &sev_cmd);
+		break;
 	default:
 		/*
 		 * If the command is compatible between CSV and SEV, the

include/uapi/linux/kvm.h

@@ -2319,6 +2319,7 @@ enum csv3_cmd_id {
 	KVM_CSV3_LAUNCH_ENCRYPT_VMCB,
 	KVM_CSV3_SEND_ENCRYPT_DATA,
 	KVM_CSV3_SEND_ENCRYPT_CONTEXT,
+	KVM_CSV3_RECEIVE_ENCRYPT_DATA,
 
 	KVM_CSV3_NR_MAX,
 };
@@ -2349,4 +2350,13 @@ struct kvm_csv3_send_encrypt_context {
 	__u32 trans_len;
 };
 
+struct kvm_csv3_receive_encrypt_data {
+	__u64 hdr_uaddr;
+	__u32 hdr_len;
+	__u64 guest_addr_data;
+	__u32 guest_addr_len;
+	__u64 trans_uaddr;
+	__u32 trans_len;
+};
+
 #endif /* __LINUX_KVM_H */