From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Cyrus-Session-Id: sloti22d1t05-560692-1519836263-2-6783557509729378824 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 0.249, ME_NOAUTH 0.01, RCVD_IN_DNSWL_HI -5, T_RP_MATCHES_RCVD -0.01, LANGUAGES en, BAYES_USED global, SA_VERSION 3.4.0 X-Spam-source: IP='209.132.180.67', Host='vger.kernel.org', Country='CN', FromHeader='uk', 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=arctest; t=1519836262; b=gPIauz5i8R5mwl0AsV2MGweOU+DjOEt/PNYFtSlTIfdp2+l UdZQMqQwN/xg+GFwN8BRf66w85etkb+W5qOKOf6xNscQAcoo3kr94exIHIjkSrUy Go9S051N+pYDexDPqF8x15I2grKcEBn98PlQbG7Cef6TpfFriH1q1nBxZ5IH7Azx cv5Q7oZ4MVQUnylGSh1Ooj/4+RKPXQ5ucXpxdAZMfzTK46tA2LLBEP9rnb3O3NIQ YUoKu4/jPkAdUlwkTBVRjqqBfc5a3yXVW/ngGiL2UCvavslDKJTmDpt3kvLZBD1P dH4kPbeoLoRAtlCOiYDIzDriRqpKDtSPrzYIJCA== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d= messagingengine.com; h=content-type:content-transfer-encoding :mime-version:from:to:cc:date:message-id:subject:in-reply-to :sender:list-id; s=arctest; t=1519836262; bh=fNGbvGRP1LSmkLhxQLv F2B5D/7pHsH7xUj7AII+aHgs=; b=snoSOOM4fmRxoJfN0p3YL4QzoYx8xGkWGTf plliEUkTL9SJh84hihFM66O9ZazTLBYJ794Hg3VK+C0LL0GavgpSQf2bWFHl0jYB TW4TiTcad9eN2fvkDL6Wt3cJmp2y5nHQum0repHDP02sSuRyZIlO64ztVK7cotmJ OKUAgLYRgNjsOHEFSq9I5r8G8ibEtZny0v+/Cf+tN2moIddKkqXGD5QX5McEOy0s bGbAdEo27Vd5ZXMTqP1nkfReMADP2M42LH3Or+9c0ckccwSvy4LZSaRJlb50gUQu 5fN7R9HXmthg/ZWZNJBZ/+ZqQXHXjKu329nQqfhDlhptSesCNvQ== 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=decadent.org.uk; 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-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=decadent.org.uk header.result=pass header_is_org_domain=yes 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=decadent.org.uk; 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-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=decadent.org.uk header.result=pass header_is_org_domain=yes Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753151AbeB1QCi (ORCPT ); Wed, 28 Feb 2018 11:02:38 -0500 Received: from shadbolt.e.decadent.org.uk ([88.96.1.126]:34718 "EHLO shadbolt.e.decadent.org.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752967AbeB1QCg (ORCPT ); Wed, 28 Feb 2018 11:02:36 -0500 Content-Type: text/plain; charset="UTF-8" Content-Disposition: inline Content-Transfer-Encoding: 8bit MIME-Version: 1.0 From: Ben Hutchings To: linux-kernel@vger.kernel.org, stable@vger.kernel.org CC: akpm@linux-foundation.org, "Nick Desaulniers" , "Takashi Iwai" , "Robb Glasser" Date: Wed, 28 Feb 2018 15:20:18 +0000 Message-ID: X-Mailer: LinuxStableQueue (scripts by bwh) Subject: [PATCH 3.16 058/254] ALSA: pcm: prevent UAF in snd_pcm_info In-Reply-To: X-SA-Exim-Connect-IP: 2a02:8011:400e:2:6f00:88c8:c921:d332 X-SA-Exim-Mail-From: ben@decadent.org.uk X-SA-Exim-Scanned: No (on shadbolt.decadent.org.uk); SAEximRunCond expanded to false 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: 3.16.55-rc1 review patch. If anyone has any objections, please let me know. ------------------ From: Robb Glasser commit 362bca57f5d78220f8b5907b875961af9436e229 upstream. When the device descriptor is closed, the `substream->runtime` pointer is freed. But another thread may be in the ioctl handler, case SNDRV_CTL_IOCTL_PCM_INFO. This case calls snd_pcm_info_user() which calls snd_pcm_info() which accesses the now freed `substream->runtime`. Note: this fixes CVE-2017-0861 Signed-off-by: Robb Glasser Signed-off-by: Nick Desaulniers Signed-off-by: Takashi Iwai Signed-off-by: Ben Hutchings --- sound/core/pcm.c | 2 ++ 1 file changed, 2 insertions(+) --- a/sound/core/pcm.c +++ b/sound/core/pcm.c @@ -150,7 +150,9 @@ static int snd_pcm_control_ioctl(struct err = -ENXIO; goto _error; } + mutex_lock(&pcm->open_mutex); err = snd_pcm_info_user(substream, info); + mutex_unlock(&pcm->open_mutex); _error: mutex_unlock(®ister_mutex); return err;