synced_folders/rsync: dup arg list [GH-3864]

CHANGELOG.md

@@ -33,6 +33,8 @@ BUG FIXES:
       disable recursive chown after sync. [GH-3810]
   - synced\_folders/rsync: Use a proper msys path if not in
       Cygwin. [GH-3804]
+  - synced\_folders/rsync: Don't append args infinitely, clear out
+      arg list on each run. [GH-3864]
 
 ## 1.6.2 (May 12, 2014)
 

plugins/synced_folders/rsync/helper.rb

@@ -77,7 +77,7 @@ module VagrantPlugins
 
         # Get the command-line arguments
         args = nil
-        args = Array(opts[:args]) if opts[:args]
+        args = Array(opts[:args]).dup if opts[:args]
         args ||= ["--verbose", "--archive", "--delete", "-z", "--copy-links"]
 
         # On Windows, we have to set a default chmod flag to avoid permission issues