Need to use list_for_entry_safe(), as we're removing items during the
traversal.  list_for_each_entry() uses the first ptr also as an iterator, if
you kfree() it slab takes it, might poison it and then you try to use it to
iterate to the next object in list.

Cc: Vojtech Pavlik <vojtech@suse.cz>
Cc: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>