--- x/drivers/misc/vmw_vmci/vmci_context.c
+++ y/drivers/misc/vmw_vmci/vmci_context.c
@@ -535,6 +535,7 @@ int vmci_ctx_dequeue_datagram(struct vmc
 			 (u32) *max_size);
 		return VMCI_ERROR_NO_MEM;
 	}
+	*max_size = dq_entry->dg_size;
 
 	list_del(list_item);
 	context->pending_datagrams--;
--- x/drivers/misc/vmw_vmci/vmci_host.c
+++ y/drivers/misc/vmw_vmci/vmci_host.c
@@ -435,7 +435,7 @@ static int vmci_host_do_receive_datagram
 
 	if (recv_info.result >= VMCI_SUCCESS) {
 		void __user *ubuf = (void __user *)(uintptr_t)recv_info.addr;
-		retval = copy_to_user(ubuf, dg, VMCI_DG_SIZE(dg));
+		retval = copy_to_user(ubuf, dg, size);
 		kfree(dg);
 		if (retval != 0)
 			return -EFAULT;