drd_handle_free is missing cli_free, so all memory allocated by client mallocs is not actually freed by client frees. this creates a notable leak.
Created attachment 24413 [details] Call cli_free to free client memory
Created attachment 24414 [details] Test case
Thanks for reporting this. This issue is fixed in SVN revision 7895, and the fix will be included in Valgrind version 3.3.1.