[ 030/101] staging: comedi: ni_labpc: fix possible NULL deref during detach

3.6-stable review patch. If anyone has any objections, please let me know. -- From: Ian Abbott commit 922b67c1ac53014d80649a961a2fde700cd065d8 upstream. `labpc_common_detach()` is called by the comedi core to clean up if either `labpc_attach()` (including the one in the

[ 030/101] staging: comedi: ni_labpc: fix possible NULL deref during detach

3.6-stable review patch. If anyone has any objections, please let me know. -- From: Ian Abbott abbo...@mev.co.uk commit 922b67c1ac53014d80649a961a2fde700cd065d8 upstream. `labpc_common_detach()` is called by the comedi core to clean up if either `labpc_attach()` (including the