From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail.linuxfoundation.org ([140.211.169.12]:47788 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752193AbdFLMtc (ORCPT ); Mon, 12 Jun 2017 08:49:32 -0400 Subject: Patch "ASoC: Fix use-after-free at card unregistration" has been added to the 4.4-stable tree To: tiwai@suse.de, broonie@kernel.org, gregkh@linuxfoundation.org, robert.jarzmik@free.fr Cc: , From: Date: Mon, 12 Jun 2017 14:49:23 +0200 Message-ID: <1497271763125165@kroah.com> MIME-Version: 1.0 Content-Type: text/plain; charset=ANSI_X3.4-1968 Content-Transfer-Encoding: 8bit Sender: stable-owner@vger.kernel.org List-ID: This is a note to let you know that I've just added the patch titled ASoC: Fix use-after-free at card unregistration to the 4.4-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: asoc-fix-use-after-free-at-card-unregistration.patch and it can be found in the queue-4.4 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let know about it. >>From 4efda5f2130da033aeedc5b3205569893b910de2 Mon Sep 17 00:00:00 2001 From: Takashi Iwai Date: Wed, 24 May 2017 10:19:45 +0200 Subject: ASoC: Fix use-after-free at card unregistration From: Takashi Iwai commit 4efda5f2130da033aeedc5b3205569893b910de2 upstream. soc_cleanup_card_resources() call snd_card_free() at the last of its procedure. This turned out to lead to a use-after-free. PCM runtimes have been already removed via soc_remove_pcm_runtimes(), while it's dereferenced later in soc_pcm_free() called via snd_card_free(). The fix is simple: just move the snd_card_free() call to the beginning of the whole procedure. This also gives another benefit: it guarantees that all operations have been shut down before actually releasing the resources, which was racy until now. Reported-and-tested-by: Robert Jarzmik Signed-off-by: Takashi Iwai Signed-off-by: Mark Brown Signed-off-by: Greg Kroah-Hartman --- sound/soc/soc-core.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) --- a/sound/soc/soc-core.c +++ b/sound/soc/soc-core.c @@ -1775,6 +1775,9 @@ static int soc_cleanup_card_resources(st for (i = 0; i < card->num_aux_devs; i++) soc_remove_aux_dev(card, i); + /* free the ALSA card at first; this syncs with pending operations */ + snd_card_free(card->snd_card); + /* remove and free each DAI */ soc_remove_dai_links(card); @@ -1786,9 +1789,7 @@ static int soc_cleanup_card_resources(st snd_soc_dapm_free(&card->dapm); - snd_card_free(card->snd_card); return 0; - } /* removes a socdev */ Patches currently in stable-queue which might be from tiwai@suse.de are queue-4.4/alsa-timer-fix-race-between-read-and-ioctl.patch queue-4.4/alsa-timer-fix-missing-queue-indices-reset-at-sndrv_timer_ioctl_select.patch queue-4.4/asoc-fix-use-after-free-at-card-unregistration.patch queue-4.4/ptrace-properly-initialize-ptracer_cred-on-fork.patch