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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 9BBC9C433EF for ; Thu, 31 Mar 2022 07:27:40 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232017AbiCaH3Y (ORCPT ); Thu, 31 Mar 2022 03:29:24 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:44668 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230421AbiCaH3X (ORCPT ); Thu, 31 Mar 2022 03:29:23 -0400 Received: from smtp-out1.suse.de (smtp-out1.suse.de [195.135.220.28]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 9EC4214751D; Thu, 31 Mar 2022 00:27:36 -0700 (PDT) Received: from relay2.suse.de (relay2.suse.de [149.44.160.134]) by smtp-out1.suse.de (Postfix) with ESMTP id 580BA21900; Thu, 31 Mar 2022 07:27:35 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=suse.de; s=susede2_rsa; t=1648711655; h=from:from:reply-to:date:date:message-id:message-id:to:to:cc:cc: mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=UxBwR/PjwnOFcNjDP3c0UR/ocYb9BAqDrgRbYKoLlfU=; b=0uqTfuyqb0f+fqZQrPgYkWTnViU0fj75smFlgEGrepqKX5wGkScT+ng+UlO5sFXCP2G1bM 47Y/HcehTl5iFStLrgpFvwJQWfi0Ek5h+hCdqy80p1dy2Zu1/hPymTyl+Yscd8aODpQpug pBrLhsZnc07kD6bvtnkSRdk1F4xTlvM= DKIM-Signature: v=1; a=ed25519-sha256; c=relaxed/relaxed; d=suse.de; s=susede2_ed25519; t=1648711655; h=from:from:reply-to:date:date:message-id:message-id:to:to:cc:cc: mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=UxBwR/PjwnOFcNjDP3c0UR/ocYb9BAqDrgRbYKoLlfU=; b=Qi54/xHZgDBTCOo9IBATm0BgiALm40S48SCQBEIQdWm3tZtm/5mYTjzkMlwskovVda8Geh Tu/Aim9rUUGnMDCw== Received: from alsa1.suse.de (alsa1.suse.de [10.160.4.42]) by relay2.suse.de (Postfix) with ESMTP id 97D8AA3B82; Thu, 31 Mar 2022 07:27:30 +0000 (UTC) Date: Thu, 31 Mar 2022 09:27:35 +0200 Message-ID: From: Takashi Iwai To: Won Chung Cc: Jaroslav Kysela , Takashi Iwai , Heikki Krogerus , Mika Westerberg , Benson Leung , Prashant Malani , linux-kernel@vger.kernel.org, stable@vger.kernel.org Subject: Re: [PATCH v2] sound/hda: Add NULL check to component match callback function In-Reply-To: <20220330211913.2068108-1-wonchung@google.com> References: <20220330211913.2068108-1-wonchung@google.com> User-Agent: Wanderlust/2.15.9 (Almost Unreal) SEMI/1.14.6 (Maruoka) FLIM/1.14.9 (=?UTF-8?B?R29qxY0=?=) APEL/10.8 Emacs/25.3 (x86_64-suse-linux-gnu) MULE/6.0 (HANACHIRUSATO) MIME-Version: 1.0 (generated by SEMI 1.14.6 - "Maruoka") Content-Type: text/plain; charset=US-ASCII Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org On Wed, 30 Mar 2022 23:19:13 +0200, Won Chung wrote: > > Component match callback function needs to check if expected data is > passed to it. Without this check, it can cause a NULL pointer > dereference when another driver registers a component before i915 > drivers have their component master fully bind. > > Fixes: 7b882fe3e3e8b ("ALSA: hda - handle multiple i915 device instances") > Signed-off-by: Heikki Krogerus > Signed-off-by: Mika Westerberg > Signed-off-by: Won Chung > --- > - Add "Fixes" tag > - Send to stable@vger.kernel.org You rather need to add "Cc: stable@vger.kernel.org" line to the patch itself (around sign-off block), not actually Cc'ing the mail. I edited manually, but please do it so at the next time. Although I applied the patch as-is now, I wonder... > - if (!strcmp(dev->driver->name, "i915") && > + if (dev->driver && !strcmp(dev->driver->name, "i915") && Can NULL dev->driver be really seen? I thought the components are added by the drivers, hence they ought to have the driver field set. But there can be corner cases I overlooked. thanks, Takashi