From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Cyrus-Session-Id: sloti22d1t05-2630128-1524406121-2-5202935674307827643 X-Sieve: CMU Sieve 3.0 X-Spam-known-sender: no X-Spam-score: 0.0 X-Spam-hits: BAYES_00 -1.9, HEADER_FROM_DIFFERENT_DOMAINS 0.25, MAILING_LIST_MULTI -1, ME_NOAUTH 0.01, RCVD_IN_DNSWL_HI -5, LANGUAGES ro, BAYES_USED global, SA_VERSION 3.4.0 X-Spam-source: IP='209.132.180.67', Host='vger.kernel.org', Country='US', FromHeader='org', MailFrom='org' X-Spam-charsets: plain='UTF-8' X-Resolved-to: greg@kroah.com X-Delivered-to: greg@kroah.com X-Mail-from: stable-owner@vger.kernel.org ARC-Seal: i=1; a=rsa-sha256; cv=none; d=messagingengine.com; s=fm2; t= 1524406120; b=E9ZpKfAjqCU6cQqtPn5psXg4Ev9SS6/GOT8W5ChfkoO0XDvJgM HjOG4mlLlN8p/EauyMXLi4B6/T5XnlDmi0B5fhiuN4GMyjPAuVlU8sK4SnLDVxzI OAbgCWYFvKfP/K1sxYCfPqXVFQKOmVnVBJFkWqDbpA963uJ5K1y69A6VwyLUcX2N 7Uonmbz02cncdg1PO5PY2YB/pkxPz4pT/KipneLpoZlHsmVRLZeOEZK8TTXJwUbT B3YrlZGUU5fmqcmCGskD3DL2ZQiHxK6ALFnYiVbbY6DpShkme8cvS/yLkBw9fCi7 wg0fAwn7aNjTAIAFwTBIiLqvOXvOFC/oIsJA== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d= messagingengine.com; h=from:to:cc:subject:date:message-id :in-reply-to:references:mime-version:content-type:sender :list-id; s=fm2; t=1524406120; bh=AT9cfOE8q0fmto1x3+C+HvHt3J8Dlx W1hiuxxykwmSQ=; b=PKhopXcb22ejmX35LXiut6XO6xSjaqRRR5+l1onodYhzdO P0m0WIhnjKLJAcX7HyWKDE0PTyYiBfXlxDBIGlmkZzjiI5niRiT7SjUPR7SfXDWY kVAm4JPmsj64+aizqP3Fc/nc27N2c5YctpvMB8Db47xUkmhwkiUhh31aaVsbsOVY jPNOTkAQGH8/kij8sHZSPErd2cSv9Wvje4mwrlp/uEVg1eTKE4VrGSxXfcusCmHn pwugtCNkrNE7VFkw3Gq9PwsDG1bgL2XJcDN4TI9o8l9tyabUWsvvPgbm65HlWS2B KV8of7Y0iVc7HBFigoQva1Fazkrr1pqy5MQ2lLGg== ARC-Authentication-Results: i=1; mx2.messagingengine.com; arc=none (no signatures found); dkim=none (no signatures found); dmarc=none (p=none,has-list-id=yes,d=none) header.from=linuxfoundation.org; iprev=pass policy.iprev=209.132.180.67 (vger.kernel.org); spf=none smtp.mailfrom=stable-owner@vger.kernel.org smtp.helo=vger.kernel.org; x-aligned-from=fail; x-cm=none score=0; x-ptr=pass x-ptr-helo=vger.kernel.org x-ptr-lookup=vger.kernel.org; x-return-mx=pass smtp.domain=vger.kernel.org smtp.result=pass smtp_org.domain=kernel.org smtp_org.result=pass smtp_is_org_domain=no header.domain=linuxfoundation.org header.result=pass header_is_org_domain=yes; x-vs=clean score=-100 state=0 Authentication-Results: mx2.messagingengine.com; arc=none (no signatures found); dkim=none (no signatures found); dmarc=none (p=none,has-list-id=yes,d=none) header.from=linuxfoundation.org; iprev=pass policy.iprev=209.132.180.67 (vger.kernel.org); spf=none smtp.mailfrom=stable-owner@vger.kernel.org smtp.helo=vger.kernel.org; x-aligned-from=fail; x-cm=none score=0; x-ptr=pass x-ptr-helo=vger.kernel.org x-ptr-lookup=vger.kernel.org; x-return-mx=pass smtp.domain=vger.kernel.org smtp.result=pass smtp_org.domain=kernel.org smtp_org.result=pass smtp_is_org_domain=no header.domain=linuxfoundation.org header.result=pass header_is_org_domain=yes; x-vs=clean score=-100 state=0 X-ME-VSCategory: clean X-CM-Envelope: MS4wfGy3dN+XQ3mP8SoXzRFah1OU+6xO5s2gq+CKykr71z8CguTusNvBYUGNo2ym7eBRzOwgsmDvb9FZabcEIrmCk/h2quOzb+i87s2I+/A4pdOYYPZP5vFQ K4IZNBPEIsTBYNAamhXtKj4+e0k68/IS7QIsKuy7wOGPE4hwwW3rVlJ0qhOUw1rNqhGC3ouRZgaoYy00N8aFCXAhk+vlka6l2b/Ivgedk0pO1zMDtfweOg0x X-CM-Analysis: v=2.3 cv=E8HjW5Vl c=1 sm=1 tr=0 a=UK1r566ZdBxH71SXbqIOeA==:117 a=UK1r566ZdBxH71SXbqIOeA==:17 a=IkcTkHD0fZMA:10 a=Kd1tUaAdevIA:10 a=yPCof4ZbAAAA:8 a=VwQbUJbxAAAA:8 a=ag1SF4gXAAAA:8 a=aLJ7TmNuWhDDgIU_xPUA:9 a=QEXdDO2ut3YA:10 a=AjGcO6oz07-iQ99wixmX:22 a=Yupwre4RP9_Eg_Bd0iYG:22 X-ME-CMScore: 0 X-ME-CMCategory: none Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755712AbeDVOIe (ORCPT ); Sun, 22 Apr 2018 10:08:34 -0400 Received: from mail.linuxfoundation.org ([140.211.169.12]:52410 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755988AbeDVOId (ORCPT ); Sun, 22 Apr 2018 10:08:33 -0400 From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Dan Carpenter , Takashi Iwai Subject: [PATCH 4.14 118/164] ALSA: pcm: Fix mutex unbalance in OSS emulation ioctls Date: Sun, 22 Apr 2018 15:53:05 +0200 Message-Id: <20180422135140.237609317@linuxfoundation.org> X-Mailer: git-send-email 2.17.0 In-Reply-To: <20180422135135.400265110@linuxfoundation.org> References: <20180422135135.400265110@linuxfoundation.org> User-Agent: quilt/0.65 X-stable: review MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Sender: stable-owner@vger.kernel.org X-Mailing-List: stable@vger.kernel.org X-getmail-retrieved-from-mailbox: INBOX X-Mailing-List: linux-kernel@vger.kernel.org List-ID: 4.14-stable review patch. If anyone has any objections, please let me know. ------------------ From: Takashi Iwai commit f6d297df4dd47ef949540e4a201230d0c5308325 upstream. The previous fix 40cab6e88cb0 ("ALSA: pcm: Return -EBUSY for OSS ioctls changing busy streams") introduced some mutex unbalance; the check of runtime->oss.rw_ref was inserted in a wrong place after the mutex lock. This patch fixes the inconsistency by rewriting with the helper functions to lock/unlock parameters with the stream check. Fixes: 40cab6e88cb0 ("ALSA: pcm: Return -EBUSY for OSS ioctls changing busy streams") Reported-by: Dan Carpenter Cc: Signed-off-by: Takashi Iwai Signed-off-by: Greg Kroah-Hartman --- sound/core/oss/pcm_oss.c | 67 +++++++++++++++++++++++++++++------------------ 1 file changed, 42 insertions(+), 25 deletions(-) --- a/sound/core/oss/pcm_oss.c +++ b/sound/core/oss/pcm_oss.c @@ -823,6 +823,23 @@ static int choose_rate(struct snd_pcm_su return snd_pcm_hw_param_near(substream, params, SNDRV_PCM_HW_PARAM_RATE, best_rate, NULL); } +/* parameter locking: returns immediately if tried during streaming */ +static int lock_params(struct snd_pcm_runtime *runtime) +{ + if (mutex_lock_interruptible(&runtime->oss.params_lock)) + return -ERESTARTSYS; + if (atomic_read(&runtime->oss.rw_ref)) { + mutex_unlock(&runtime->oss.params_lock); + return -EBUSY; + } + return 0; +} + +static void unlock_params(struct snd_pcm_runtime *runtime) +{ + mutex_unlock(&runtime->oss.params_lock); +} + /* call with params_lock held */ static int snd_pcm_oss_change_params_locked(struct snd_pcm_substream *substream) { @@ -1721,6 +1738,8 @@ static int snd_pcm_oss_set_rate(struct s for (idx = 1; idx >= 0; --idx) { struct snd_pcm_substream *substream = pcm_oss_file->streams[idx]; struct snd_pcm_runtime *runtime; + int err; + if (substream == NULL) continue; runtime = substream->runtime; @@ -1728,15 +1747,14 @@ static int snd_pcm_oss_set_rate(struct s rate = 1000; else if (rate > 192000) rate = 192000; - if (mutex_lock_interruptible(&runtime->oss.params_lock)) - return -ERESTARTSYS; - if (atomic_read(&runtime->oss.rw_ref)) - return -EBUSY; + err = lock_params(runtime); + if (err < 0) + return err; if (runtime->oss.rate != rate) { runtime->oss.params = 1; runtime->oss.rate = rate; } - mutex_unlock(&runtime->oss.params_lock); + unlock_params(runtime); } return snd_pcm_oss_get_rate(pcm_oss_file); } @@ -1761,18 +1779,19 @@ static int snd_pcm_oss_set_channels(stru for (idx = 1; idx >= 0; --idx) { struct snd_pcm_substream *substream = pcm_oss_file->streams[idx]; struct snd_pcm_runtime *runtime; + int err; + if (substream == NULL) continue; runtime = substream->runtime; - if (mutex_lock_interruptible(&runtime->oss.params_lock)) - return -ERESTARTSYS; - if (atomic_read(&runtime->oss.rw_ref)) - return -EBUSY; + err = lock_params(runtime); + if (err < 0) + return err; if (runtime->oss.channels != channels) { runtime->oss.params = 1; runtime->oss.channels = channels; } - mutex_unlock(&runtime->oss.params_lock); + unlock_params(runtime); } return snd_pcm_oss_get_channels(pcm_oss_file); } @@ -1845,6 +1864,7 @@ static int snd_pcm_oss_get_formats(struc static int snd_pcm_oss_set_format(struct snd_pcm_oss_file *pcm_oss_file, int format) { int formats, idx; + int err; if (format != AFMT_QUERY) { formats = snd_pcm_oss_get_formats(pcm_oss_file); @@ -1858,15 +1878,14 @@ static int snd_pcm_oss_set_format(struct if (substream == NULL) continue; runtime = substream->runtime; - if (atomic_read(&runtime->oss.rw_ref)) - return -EBUSY; - if (mutex_lock_interruptible(&runtime->oss.params_lock)) - return -ERESTARTSYS; + err = lock_params(runtime); + if (err < 0) + return err; if (runtime->oss.format != format) { runtime->oss.params = 1; runtime->oss.format = format; } - mutex_unlock(&runtime->oss.params_lock); + unlock_params(runtime); } } return snd_pcm_oss_get_format(pcm_oss_file); @@ -1914,12 +1933,11 @@ static int snd_pcm_oss_set_subdivide(str if (substream == NULL) continue; runtime = substream->runtime; - if (atomic_read(&runtime->oss.rw_ref)) - return -EBUSY; - if (mutex_lock_interruptible(&runtime->oss.params_lock)) - return -ERESTARTSYS; + err = lock_params(runtime); + if (err < 0) + return err; err = snd_pcm_oss_set_subdivide1(substream, subdivide); - mutex_unlock(&runtime->oss.params_lock); + unlock_params(runtime); if (err < 0) return err; } @@ -1954,12 +1972,11 @@ static int snd_pcm_oss_set_fragment(stru if (substream == NULL) continue; runtime = substream->runtime; - if (atomic_read(&runtime->oss.rw_ref)) - return -EBUSY; - if (mutex_lock_interruptible(&runtime->oss.params_lock)) - return -ERESTARTSYS; + err = lock_params(runtime); + if (err < 0) + return err; err = snd_pcm_oss_set_fragment1(substream, val); - mutex_unlock(&runtime->oss.params_lock); + unlock_params(runtime); if (err < 0) return err; }