From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-10.3 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,MAILING_LIST_MULTI, SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_1 autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id B180DC11F67 for ; Tue, 29 Jun 2021 14:32:56 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 91E8061D40 for ; Tue, 29 Jun 2021 14:32:56 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S234440AbhF2OfW (ORCPT ); Tue, 29 Jun 2021 10:35:22 -0400 Received: from netrider.rowland.org ([192.131.102.5]:34777 "HELO netrider.rowland.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with SMTP id S234285AbhF2OfT (ORCPT ); Tue, 29 Jun 2021 10:35:19 -0400 Received: (qmail 699680 invoked by uid 1000); 29 Jun 2021 10:32:51 -0400 Date: Tue, 29 Jun 2021 10:32:51 -0400 From: Alan Stern To: Linyu Yuan Cc: Felipe Balbi , Thinh Nguyen , Greg Kroah-Hartman , linux-usb@vger.kernel.org, linux-kernel@vger.kernel.org, Jack Pham Subject: Re: [PATCH v2] usb: dwc3: avoid NULL access of usb_gadget_driver Message-ID: <20210629143251.GA699290@rowland.harvard.edu> References: <20210629015118.7944-1-linyyuan@codeaurora.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20210629015118.7944-1-linyyuan@codeaurora.org> User-Agent: Mutt/1.10.1 (2018-07-13) Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, Jun 29, 2021 at 09:51:18AM +0800, Linyu Yuan wrote: > we found crash in dwc3_disconnect_gadget(), > it is because dwc->gadget_driver become NULL before async access. > 7dc0c55e9f30 ('USB: UDC core: Add udc_async_callbacks gadget op') > suggest a common way to avoid such kind of issue. > > this change implment the callback in dwc3 and > change related functions which have callback to usb gadget driver. > > Signed-off-by: Linyu Yuan > --- > > v2: add missing check in dwc3_reset_gadget(), found by Alan Stern. This is better. Acked-by: Alan Stern