Halt Vagrant if within WSL and attempting to operate out of rootfs

lib/vagrant/errors.rb

@@ -895,5 +895,9 @@ module Vagrant
     class WSLVagrantVersionMismatch < VagrantError
       error_key(:wsl_vagrant_version_mismatch)
     end
+
+    class WSLVagrantAccessError < VagrantError
+      error_key(:wsl_vagrant_access_error)
+    end
   end
 end

lib/vagrant/util/platform.rb

@@ -290,9 +290,11 @@ module Vagrant
         # simple setup to allow sharing of the user's VAGRANT_HOME directory
         # within the subsystem
         #
+        # @param [Environment] env
         # @param [Logger] logger Optional logger to display information
-        def wsl_init(logger=nil)
+        def wsl_init(env, logger=nil)
-          if wsl? && ENV["VAGRANT_WSL_ACCESS_WINDOWS_USER"]
+          if wsl?
+            if ENV["VAGRANT_WSL_ACCESS_WINDOWS_USER"]
               wsl_validate_matching_vagrant_versions!
               shared_user = ENV["VAGRANT_WSL_ACCESS_WINDOWS_USER"]
               if logger
@@ -308,6 +310,11 @@ module Vagrant
                   logger.info("Overriding VAGRANT_HOME environment variable to configured windows user. (#{ENV["VAGRANT_HOME"]})")
                 end
               end
+            else
+              if env.local_data_path.to_s.start_with?("/mnt/")
+                raise Vagrant::Errors::WSLVagrantAccessError
+              end
+            end
           end
         end
 
@@ -319,13 +326,14 @@ module Vagrant
           if result.exit_code == 0
             windows_version = result.stdout.match(/Installed Version: (?<version>.+$)/)
             if windows_version
-              valid = windows_version[:version] == Vagrant::VERSION
+              windows_version = windows_version[:version].strip
+              valid = windows_version == Vagrant::VERSION
             end
           end
           if !valid
             raise Vagrant::Errors::WSLVagrantVersionMismatch,
               wsl_version: Vagrant::VERSION,
-              windows_version: windows_version ? windows_version[:version] : "unknown"
+              windows_version: windows_version || "unknown"
           end
         end
 

templates/locales/en.yml

@@ -1530,6 +1530,14 @@ en:
 
           Windows Vagrant version: %{windows_version}
           Windows Subsystem for Linux Vagrant version: %{wsl_version}
+      wsl_vagrant_access_error: |-
+        Vagrant will not operate outside the Windows Subsystem for Linux unless explicitly
+        instructed. Due to the inability to enforce expected Linux file ownership and
+        permissions on the Windows system, Vagrant will not make modifications to prevent
+        unexpected errors. To learn more about this, and the options that are available,
+        please refer to the Vagrant documentation:
+
+          https://www.vagrantup.com/docs/other/wsl
 
 #-------------------------------------------------------------------------------
 # Translations for config validation errors