From: Tom Rix <trix@xxxxxxxxxx> clang static analysis flags this representive problem net2272.c:1541:8: warning: Dereference of null pointer if ((req->req.length % ep->ep.maxpacket != 0) || ^~~~~~~~~~~~~~~ This is mostly not a problem. In net2272_handle_dma(), even though every path through the routine dereferences req, it is set to NULL when the ep->queue is empty. If the eq->queue was ever empty this would have oops. So the else statement should not be needed. If it is, flag it as a BUG. Signed-off-by: Tom Rix <trix@xxxxxxxxxx> --- drivers/usb/gadget/udc/net2272.c | 5 ++--- 1 file changed, 2 insertions(+), 3 deletions(-) diff --git a/drivers/usb/gadget/udc/net2272.c b/drivers/usb/gadget/udc/net2272.c index 44d1ea2307bb..8301723a8b1a 100644 --- a/drivers/usb/gadget/udc/net2272.c +++ b/drivers/usb/gadget/udc/net2272.c @@ -1506,17 +1506,16 @@ static int net2272_stop(struct usb_gadget *_gadget) static void net2272_handle_dma(struct net2272_ep *ep) { - struct net2272_request *req; + struct net2272_request *req = NULL; unsigned len; int status; if (!list_empty(&ep->queue)) req = list_entry(ep->queue.next, struct net2272_request, queue); - else - req = NULL; dev_vdbg(ep->dev->dev, "handle_dma %s req %p\n", ep->ep.name, req); + BUG_ON(!req); /* Ensure DREQ is de-asserted */ net2272_write(ep->dev, DMAREQ, -- 2.18.1