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=-0.9 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_PASS, T_DKIMWL_WL_HIGH,URIBL_BLOCKED autolearn=ham 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 05F3EECDFB8 for ; Wed, 18 Jul 2018 10:58:29 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 5B09F2084E for ; Wed, 18 Jul 2018 10:58:28 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=samsung.com header.i=@samsung.com header.b="qCXf2A0p" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 5B09F2084E Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=samsung.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730627AbeGRLfq (ORCPT ); Wed, 18 Jul 2018 07:35:46 -0400 Received: from mailout1.samsung.com ([203.254.224.24]:49262 "EHLO mailout1.samsung.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728283AbeGRLfq (ORCPT ); Wed, 18 Jul 2018 07:35:46 -0400 Received: from epcas5p1.samsung.com (unknown [182.195.41.39]) by mailout1.samsung.com (KnoxPortal) with ESMTP id 20180718105823epoutp0189ef2fa9635f6fd01a8a90b15f1676c1~CcWVjVb8s0559705597epoutp01n for ; Wed, 18 Jul 2018 10:58:23 +0000 (GMT) DKIM-Filter: OpenDKIM Filter v2.11.0 mailout1.samsung.com 20180718105823epoutp0189ef2fa9635f6fd01a8a90b15f1676c1~CcWVjVb8s0559705597epoutp01n DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=samsung.com; s=mail20170921; t=1531911503; bh=P0riJyq8+InZtyM/n9tMKUyI4cuoACFPQJbFNHqBg7g=; h=Subject:Reply-To:From:To:CC:In-Reply-To:Date:References:From; b=qCXf2A0psSnTXklkl5OfLdKHkU8z/zMzytluGAllshq4exPB5hEvkYHbMZFbMIf95 Q0A0rVZE9Ujk0sLUrX5m22KdXraPbgvUNwj/2xGankFJSALZtl2/u/fmi1vUgR/cAL aTTZxfku7TTfHtiWOp+pxopJTRyanCGjzyVxe3AU= Received: from epsmges5p1new.samsung.com (unknown [182.195.40.194]) by epcas5p3.samsung.com (KnoxPortal) with ESMTP id 20180718105821epcas5p36527f3577fd68442e753d58d1d9918e4~CcWTg2w380092300923epcas5p3m; Wed, 18 Jul 2018 10:58:21 +0000 (GMT) X-AuditID: b6c32a49-aefff70000001142-be-5b4f1d4d9044 Received: from epcas5p1.samsung.com ( [182.195.41.39]) by epsmges5p1new.samsung.com (Symantec Messaging Gateway) with SMTP id 2D.23.04418.D4D1F4B5; Wed, 18 Jul 2018 19:58:21 +0900 (KST) Mime-Version: 1.0 Subject: RE: Re: [PATCH 1/1] Preventive fix in sound module Reply-To: srikanth.h@samsung.com From: Srikanth Korangala Hari To: Takashi Iwai CC: "alsa-devel@alsa-project.org" , "keescook@chromium.org" , "ben.hutchings@codethink.co.uk" , "perex@perex.cz" , "elfring@users.sourceforge.net" , "linux-kernel@vger.kernel.org" , "viro@zeniv.linux.org.uk" , CPGS X-Priority: 3 X-Content-Kind-Code: NORMAL In-Reply-To: X-Drm-Type: N,general X-Msg-Generator: Mail X-Msg-Type: PERSONAL X-Reply-Demand: N Message-ID: <20180718105820epcms5p173879897edd4cc93b381f8125c11b91b@epcms5p1> Date: Wed, 18 Jul 2018 16:28:20 +0530 X-CMS-MailID: 20180718105820epcms5p173879897edd4cc93b381f8125c11b91b Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" X-CPGSPASS: Y CMS-TYPE: 105P X-Brightmail-Tracker: H4sIAAAAAAAAA+NgFlrNJsWRmVeSWpSXmKPExsWy7bCmuq6vrH+0wZl3ghZXLh5isrix8x+r xctDmhbnO5czW5zpzrW4vGsOm0Xnrn6g8OY3TBbn/x5ndeD02PC5ic1jdsNFFo9nLyczeex7 u4zNo2/LKkaPzaerPZpOtbN6fN4k57HpyVumAM6oVJuM1MSU1CKF1Lzk/JTMvHRbJe/geOd4 UzMDQ11DSwtzJYW8xNxUWyUXnwBdt8wcoAuVFMoSc0qBQgGJxcVK+nY2RfmlJakKGfnFJbZK 0YaGRnqGBuZ6RkZA2jTWysgUqCQhNaPn/COWgvNSFU0Hr7I3MH6V7GLk5JAQMJF4e24KUxcj F4eQwG5GiS8/7rN2MXJw8AoISvzdIQxSIyxgLfFv2gWwsJCAgsStVdEQYQuJSTM6mUFsNgEz iZ7ve5hAbBGgkjev7jGCjGQWWMcs8X/TS2aIXbwSM9qfskDY0hLbl29lBLE5BbQlTq+bzgQR F5W4ufotO4z9/th8RghbRKL13lmoOYISD37uZoSZ8/4YxP0SApMZJb7+3MkC4axmlNh/6AXU NnOJxzc3g23gFfCVODfxDQvINywCqhLb+4UhSlwk5v+/yAZiMwMdtGzha2aQEmYBTYn1u/Rh 7m/Y+JsdooRPovf3EyaY+I55IDYHkK0i8WB/GYQpJdH7yQ6iwkNi5fZ+dkgor2OUWLVmMdME RoVZiICehWTvLIS9CxiZVzFKphYU56anFpsWGOallusVJ+YWl+al6yXn525iBCdULc8djLPO +RxiFOBgVOLhPfDfN1qINbGsuDL3EKMEB7OSCO/B937RQrwpiZVVqUX58UWlOanFhxhNgQEw kVlKNDkfmOzzSuINTY3MzAwsDUyNLcwMlcR5z/F6RAsJpCeWpGanphakFsH0MXFwSjUwbuDR M5ncov3/Q14Vy3xljl0GzGczN20o5/c63sM1bc9Ov6rumFxpFq9G3puPWlZNeSbNnGv00U7U 7hPTwiUcnxvlzrD93np+5rKGB/K2sabHZrsdu5/9X0VR+eyn0BwWm5yQU32L39S56ul8+HVg OtP+eZ0iEo1P1FrKTCZ2Ri031gjavT5QiaU4I9FQi7moOBEA7P16Tb4DAAA= DLP-Filter: Pass X-CFilter-Loop: Reflected X-CMS-RootMailID: 20180718100741epcas1p393bea852d102e903ab6a48ff952761db References: <1531908468-1352-1-git-send-email-srikanth.h@samsung.com> Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org >>=C2=A0=0D=0A>>=C2=A0Signed-off-by:=C2=A0Srikanth=C2=A0K=C2=A0H=C2=A0=0D=0A=C2=A0=0D=0A>What=C2=A0does=C2=A0this=C2=A0fix,= =C2=A0and=C2=A0above=C2=A0all,=C2=A0why=C2=A0is=C2=A0this=C2=A0needed?=0D= =0A=0D=0AHi,=0D=0A=0D=0AWhen=20the=20sound=20driver=20creates=20the=20timer= =20without=20sound=20card=20object,=20then=20while=20reading=20the=20sound= =20info=20entry=20the=20timer=20object=E2=80=99s=20card=20information=20is= =20dereferenced=20without=20checking=20for=20NULL=20pointer=20which=20will= =20result=20for=20kernel=20panic.=20I=20tried=20to=20simulate=20this=20scen= ario=20and=20got=20below=20call=20stack,=0D=0A=5B=20=20=2036.668=5D=20E/DEV= KMSG=20(P=20=20=20=200,=20T=20=20=20=200):=20Unable=20to=20handle=20kernel= =20NULL=20pointer=20dereference=20at=20virtual=20address=2000000000=0D=0A= =5B=20=20=2036.668=5D=20E/DEVKMSG=20(P=20=20=20=200,=20T=20=20=20=200):=20p= gd=20=3D=20e52f0000=0D=0A=5B=20=20=2036.668=5D=20E/DEVKMSG=20(P=20=20=20=20= 0,=20T=20=20=20=200):=20=5B00000000=5D=20*pgd=3D00000000=0D=0A=5B=20=20=203= 6.668=5D=20E/DEVKMSG=20(P=20=20=20=200,=20T=20=20=20=200):=20Internal=20err= or:=20Oops:=205=20=5B=231=5D=20PREEMPT=20SMP=20ARM=0D=0A=5B=20=20=2036.668= =5D=20E/DEVKMSG=20(P=20=20=20=200,=20T=20=20=20=200):=20Modules=20linked=20= in:=0D=0A=5B=20=20=2036.668=5D=20E/DEVKMSG=20(P=20=20=20=200,=20T=20=20=20= =200):=20CPU:=201=20PID:=201258=20Comm:=20cat=20Tainted:=20G=20=20=20=20=20= =20=20=20W=20=20=20=203.10.65-00121-g83e9b9b-dirty=20=2354-Tizen=0D=0A=5B= =20=20=2036.668=5D=20E/DEVKMSG=20(P=20=20=20=200,=20T=20=20=20=200):=20task= :=20e653aec0=20ti:=20e52ec000=20task.ti:=20e52ec000=0D=0A=5B=20=20=2036.668= =5D=20E/DEVKMSG=20(P=20=20=20=200,=20T=20=20=20=200):=20PC=20is=20at=20snd_= timer_proc_read+0x104/0x278=0D=0A=5B=20=20=2036.668=5D=20E/DEVKMSG=20(P=20= =20=20=200,=20T=20=20=20=200):=20LR=20is=20at=20snd_timer_proc_read+0xec/0x= 278=0D=0A=5B=20=20=2036.668=5D=20E/DEVKMSG=20(P=20=20=20=200,=20T=20=20=20= =200):=20pc=20:=20=5B=5D=20=20=20=20lr=20:=20=5B=5D=20= =20=20=20psr:=2060040013=5Cx0asp=20:=20e52eded0=20=20ip=20:=2000000000=20= =20fp=20:=2010624dd3=0D=0A=5B=20=20=2036.668=5D=20E/DEVKMSG=20(P=20=20=20= =200,=20T=20=20=20=200):=20r10:=20c08ded6c=20=20r9=20:=20e49e3bd8=20=20r8= =20:=20c074f518=0D=0A=5B=20=20=2036.668=5D=20E/DEVKMSG=20(P=20=20=20=200,= =20T=20=20=20=200):=20r7=20:=20c0afbae4=20=20r6=20:=20eb95a000=20=20r5=20:= =20e49e3240=20=20r4=20:=20eb257e00=0D=0A=5B=20=20=2036.668=5D=20E/DEVKMSG= =20(P=20=20=20=200,=20T=20=20=20=200):=20r3=20:=2000000000=20=20r2=20:=2000= 000000=20=20r1=20:=20c0987cd7=20=20r0=20:=20e49e3240=0D=0A=5B=20=20=2036.66= 8=5D=20E/DEVKMSG=20(P=20=20=20=200,=20T=20=20=20=200):=20Flags:=20nZCv=20= =20IRQs=20on=20=20FIQs=20on=20=20Mode=20SVC_32=20=20ISA=20ARM=20=20Segment= =20user=0D=0A=5B=20=20=2036.668=5D=20E/DEVKMSG=20(P=20=20=20=200,=20T=20=20= =20=200):=20Control:=2010c53c7d=20=20Table:=20a52f006a=20=20DAC:=2000000015= =0D=0A=0D=0AHence=20this=20is=20a=20preventive=20patch=20to=20avoid=20kerne= l=20panic=20in=20case=20if=20the=20card=20object=20passed=20to=20timer=20fu= nction=20is=20NULL.=20This=20would=20not=20happen=20in=20normal=20case,=20b= ut=20in=20case=20of=20buggy=20scenario=20this=20would=20results=20in=20kern= el=20panic=20rather=20than=20graceful=20exit.=0D=0A=0D=0Athanks,=0D=0Asrika= nth