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=-8.2 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_1 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 59D84C2D0C2 for ; Mon, 30 Dec 2019 19:37:10 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 2BFA1206DB for ; Mon, 30 Dec 2019 19:37:10 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="TOAZ66X1" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727695AbfL3ThJ (ORCPT ); Mon, 30 Dec 2019 14:37:09 -0500 Received: from mail-lf1-f66.google.com ([209.85.167.66]:43122 "EHLO mail-lf1-f66.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727278AbfL3ThI (ORCPT ); Mon, 30 Dec 2019 14:37:08 -0500 Received: by mail-lf1-f66.google.com with SMTP id 9so25768751lfq.10; Mon, 30 Dec 2019 11:37:07 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=subject:to:cc:references:from:message-id:date:user-agent :mime-version:in-reply-to:content-language:content-transfer-encoding; bh=qOOSKaKHeFnod5RsK2x90NOSdkdcsmV7T1nxZJUbNFM=; b=TOAZ66X1HMUwmsDMiHpQaMSWjWbrMckRdF29Qmkw7WUdjCLexTFaLygZn8cL9rW5i9 u2nmP4MGXAdzM0V0vWb85sv0RkLb+sc2jJhz7mF9tJVpf5W5VR9tqxPD4Ee0550aYaaB 3wA9OdqVgQ6eN3NMBX/IPlw8gPc4WmGEmxVt2+Ze6lJB7g8edNyM7l7ObYvqwMgvkyRp LpVqziMyB7SbH3CCkTDL9J0gfxSHQPbZN0W3lQk3cwNHRflk4wNHe3EBHN4D/JU5Vawv /M21K4hjE5XCMVwZVwQCvzBA/zESjM0aS9G1mluJAS1TxItdyZPOM+DYk9yniyZHx3aE bLOA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:subject:to:cc:references:from:message-id:date :user-agent:mime-version:in-reply-to:content-language :content-transfer-encoding; bh=qOOSKaKHeFnod5RsK2x90NOSdkdcsmV7T1nxZJUbNFM=; b=WDyPpa9tLMC1ctYbrXpwDKOw0jFVFDZv4coynqAbT9dAEnisAAs8Aqu6tMbgiT1K+H dxHDw0HwVF2/K+l2jeWDGwZpk55uXgbF9nv0M1dfM9Gc4/laoP0RomKLAzguYBSdmLzg SW9cWqhvbG6ZyW2dLrQQaH4XXIT4fu8kse1LJ7T+5x9NKhcDEP/NZJutd9HSgs7Zi1pB wEoRXCMl7dP9s7dwlAmfWBbosAybBqjuJH1oIt0hXTpl8tD+JCHbwWLHnWfPPw/p4DzJ o+G7y/U64FkYYtcpuQrt4XG4YaPtaTitXwrsrji83lZiQ/9FxFuvOXe7afPJ96ZELO3s TuLw== X-Gm-Message-State: APjAAAUreLJpmKhwaGMyCFAzsavaXdmTOVvhU/Yldci1AKfA3DJSpbwU tP/hYqfp88eeFJOUAnSFTwog6Mmm X-Google-Smtp-Source: APXvYqxazqU9rDtT0rPVHMMgwW7B4Kv0P8Jgclqa/eU938P2WNSQlrWfofGwQnG/j+Id1P8xPxj4ag== X-Received: by 2002:ac2:41c8:: with SMTP id d8mr38454027lfi.65.1577734626358; Mon, 30 Dec 2019 11:37:06 -0800 (PST) Received: from [192.168.2.145] (79-139-233-37.dynamic.spd-mgts.ru. [79.139.233.37]) by smtp.googlemail.com with ESMTPSA id m15sm18353822ljg.4.2019.12.30.11.37.04 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Mon, 30 Dec 2019 11:37:04 -0800 (PST) Subject: Re: [PATCH v1] ASoC: rt5640: Fix NULL dereference on module unload To: Takashi Iwai Cc: Thierry Reding , Jonathan Hunter , Mark Brown , Jaroslav Kysela , Bard Liao , Oder Chiou , Liam Girdwood , Takashi Iwai , linux-tegra@vger.kernel.org, alsa-devel@alsa-project.org, linux-kernel@vger.kernel.org References: <20191229150454.2127-1-digetx@gmail.com> From: Dmitry Osipenko Message-ID: <68754394-fb34-b109-264a-98f36d05ff2a@gmail.com> Date: Mon, 30 Dec 2019 22:37:03 +0300 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:68.0) Gecko/20100101 Thunderbird/68.3.0 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 30.12.2019 10:11, Takashi Iwai пишет: > On Sun, 29 Dec 2019 16:04:54 +0100, > Dmitry Osipenko wrote: >> >> The rt5640->jack is NULL if jack is already disabled at the time of >> driver's module unloading. >> >> Unable to handle kernel NULL pointer dereference at virtual address 00000024 >> ... >> (rt5640_set_jack [snd_soc_rt5640]) from [] (snd_soc_component_set_jack+0x11/0x1c [snd_soc_core]) >> (snd_soc_component_set_jack [snd_soc_core]) from [] (soc_remove_component+0x1b/0x54 [snd_soc_core]) >> (soc_remove_component [snd_soc_core]) from [] (soc_cleanup_card_resources+0xad/0x1cc [snd_soc_core]) >> (soc_cleanup_card_resources [snd_soc_core]) from [] (snd_soc_unregister_card+0x47/0x78 [snd_soc_core]) >> (snd_soc_unregister_card [snd_soc_core]) from [] (tegra_rt5640_remove+0x13/0x1c [snd_soc_tegra_rt5640]) >> (tegra_rt5640_remove [snd_soc_tegra_rt5640]) from [] (platform_drv_remove+0x17/0x24) >> (platform_drv_remove) from [] (device_release_driver_internal+0x95/0x114) >> (device_release_driver_internal) from [] (driver_detach+0x4d/0x90) >> (driver_detach) from [] (bus_remove_driver+0x31/0x70) >> (bus_remove_driver) from [] (tegra_rt5640_driver_exit+0x9/0xdf4 [snd_soc_tegra_rt5640]) >> (tegra_rt5640_driver_exit [snd_soc_tegra_rt5640]) from [] (sys_delete_module+0xe7/0x184) >> (sys_delete_module) from [] (ret_fast_syscall+0x1/0x28) >> >> Signed-off-by: Dmitry Osipenko >> --- >> sound/soc/codecs/rt5640.c | 22 ++++++++++++++-------- >> 1 file changed, 14 insertions(+), 8 deletions(-) >> >> diff --git a/sound/soc/codecs/rt5640.c b/sound/soc/codecs/rt5640.c >> index adbae1f36a8a..b245c44cafbc 100644 >> --- a/sound/soc/codecs/rt5640.c >> +++ b/sound/soc/codecs/rt5640.c >> @@ -2432,16 +2432,22 @@ static void rt5640_disable_jack_detect(struct snd_soc_component *component) >> { >> struct rt5640_priv *rt5640 = snd_soc_component_get_drvdata(component); >> >> - disable_irq(rt5640->irq); >> - rt5640_cancel_work(rt5640); >> + /* >> + * soc_remove_component() force-disables jack and thus rt5640->jack >> + * could be NULL at the time of driver's module unloading. >> + */ >> + if (rt5640->jack) { >> + disable_irq(rt5640->irq); >> + rt5640_cancel_work(rt5640); >> >> - if (rt5640->jack->status & SND_JACK_MICROPHONE) { >> - rt5640_disable_micbias1_ovcd_irq(component); >> - rt5640_disable_micbias1_for_ovcd(component); >> - snd_soc_jack_report(rt5640->jack, 0, SND_JACK_BTN_0); >> - } >> + if (rt5640->jack->status & SND_JACK_MICROPHONE) { >> + rt5640_disable_micbias1_ovcd_irq(component); >> + rt5640_disable_micbias1_for_ovcd(component); >> + snd_soc_jack_report(rt5640->jack, 0, SND_JACK_BTN_0); >> + } >> >> - rt5640->jack = NULL; >> + rt5640->jack = NULL; >> + } >> } > > I guess it's simpler just returning if rt5640->jack is already NULL. > > --- a/sound/soc/codecs/rt5640.c > +++ b/sound/soc/codecs/rt5640.c > @@ -2432,6 +2432,10 @@ static void rt5640_disable_jack_detect(struct snd_soc_component *component) > { > struct rt5640_priv *rt5640 = snd_soc_component_get_drvdata(component); > > + /* already disabled? */ > + if (!rt5640->jack) > + return; > + > disable_irq(rt5640->irq); > rt5640_cancel_work(rt5640); > > > thanks, > > Takashi > Okay, I'll make v2.