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 779E6C43219 for ; Mon, 7 Feb 2022 11:46:58 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1387046AbiBGLiu (ORCPT ); Mon, 7 Feb 2022 06:38:50 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:45042 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1385490AbiBGLbz (ORCPT ); Mon, 7 Feb 2022 06:31:55 -0500 Received: from dfw.source.kernel.org (dfw.source.kernel.org [139.178.84.217]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 55260C03E952; Mon, 7 Feb 2022 03:30:34 -0800 (PST) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id D9F346077B; Mon, 7 Feb 2022 11:30:33 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id AFE2DC004E1; Mon, 7 Feb 2022 11:30:32 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1644233433; bh=5OlD3dhXOCojKO3N7H+U3aupk719bOzjvga7rhxB4wA=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=lQlkwCeQH2nm+ActBsIL3oOEctHfOKCEpl504jYoNdbarnRLpTWZxBdPHJnsVzJbg Bn8zQWCzoTXvsJy/DbgKvojJvFvxybGsW86rexdbHrEnh+Khdw/ItsIKF42DCF4Dcs eUimsYSBk51YU72ZgbkX/2hNMUUs/MU9aPS5e58g= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Alexander Sergeyev , Takashi Iwai Subject: [PATCH 5.16 011/126] ALSA: hda: Fix UAF of leds class devs at unbinding Date: Mon, 7 Feb 2022 12:05:42 +0100 Message-Id: <20220207103804.452290450@linuxfoundation.org> X-Mailer: git-send-email 2.35.1 In-Reply-To: <20220207103804.053675072@linuxfoundation.org> References: <20220207103804.053675072@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Takashi Iwai commit 549f8ffc7b2f7561bea7f90930b6c5104318e87b upstream. The LED class devices that are created by HD-audio codec drivers are registered via devm_led_classdev_register() and associated with the HD-audio codec device. Unfortunately, it turned out that the devres release doesn't work for this case; namely, since the codec resource release happens before the devm call chain, it triggers a NULL dereference or a UAF for a stale set_brightness_delay callback. For fixing the bug, this patch changes the LED class device register and unregister in a manual manner without devres, keeping the instances in hda_gen_spec. Reported-by: Alexander Sergeyev Cc: Link: https://lore.kernel.org/r/20220111195229.a77wrpjclqwrx4bx@localhost.localdomain Link: https://lore.kernel.org/r/20220126145011.16728-1-tiwai@suse.de Signed-off-by: Takashi Iwai Signed-off-by: Greg Kroah-Hartman --- sound/pci/hda/hda_generic.c | 17 +++++++++++++++-- sound/pci/hda/hda_generic.h | 3 +++ 2 files changed, 18 insertions(+), 2 deletions(-) --- a/sound/pci/hda/hda_generic.c +++ b/sound/pci/hda/hda_generic.c @@ -91,6 +91,12 @@ static void snd_hda_gen_spec_free(struct free_kctls(spec); snd_array_free(&spec->paths); snd_array_free(&spec->loopback_list); +#ifdef CONFIG_SND_HDA_GENERIC_LEDS + if (spec->led_cdevs[LED_AUDIO_MUTE]) + led_classdev_unregister(spec->led_cdevs[LED_AUDIO_MUTE]); + if (spec->led_cdevs[LED_AUDIO_MICMUTE]) + led_classdev_unregister(spec->led_cdevs[LED_AUDIO_MICMUTE]); +#endif } /* @@ -3922,7 +3928,10 @@ static int create_mute_led_cdev(struct h enum led_brightness), bool micmute) { + struct hda_gen_spec *spec = codec->spec; struct led_classdev *cdev; + int idx = micmute ? LED_AUDIO_MICMUTE : LED_AUDIO_MUTE; + int err; cdev = devm_kzalloc(&codec->core.dev, sizeof(*cdev), GFP_KERNEL); if (!cdev) @@ -3932,10 +3941,14 @@ static int create_mute_led_cdev(struct h cdev->max_brightness = 1; cdev->default_trigger = micmute ? "audio-micmute" : "audio-mute"; cdev->brightness_set_blocking = callback; - cdev->brightness = ledtrig_audio_get(micmute ? LED_AUDIO_MICMUTE : LED_AUDIO_MUTE); + cdev->brightness = ledtrig_audio_get(idx); cdev->flags = LED_CORE_SUSPENDRESUME; - return devm_led_classdev_register(&codec->core.dev, cdev); + err = led_classdev_register(&codec->core.dev, cdev); + if (err < 0) + return err; + spec->led_cdevs[idx] = cdev; + return 0; } /** --- a/sound/pci/hda/hda_generic.h +++ b/sound/pci/hda/hda_generic.h @@ -294,6 +294,9 @@ struct hda_gen_spec { struct hda_jack_callback *cb); void (*mic_autoswitch_hook)(struct hda_codec *codec, struct hda_jack_callback *cb); + + /* leds */ + struct led_classdev *led_cdevs[NUM_AUDIO_LEDS]; }; /* values for add_stereo_mix_input flag */