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=-12.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT 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 CDB2FC433E1 for ; Wed, 19 Aug 2020 06:31:11 +0000 (UTC) Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 952A620772 for ; Wed, 19 Aug 2020 06:31:11 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=hostfission.com header.i=@hostfission.com header.b="rXCT6QKa" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 952A620772 Authentication-Results: mail.kernel.org; dmarc=fail (p=reject dis=none) header.from=hostfission.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Received: from localhost ([::1]:50620 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1k8Hcs-0006dQ-SA for qemu-devel@archiver.kernel.org; Wed, 19 Aug 2020 02:31:10 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:60152) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1k8HbU-0005Ej-PJ for qemu-devel@nongnu.org; Wed, 19 Aug 2020 02:29:44 -0400 Received: from mail1.hostfission.com ([139.99.139.48]:32910) by eggs.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1k8HbS-0003xP-Sm for qemu-devel@nongnu.org; Wed, 19 Aug 2020 02:29:44 -0400 Received: from moya.office.hostfission.com (office.hostfission.com [220.233.29.71]) by mail1.hostfission.com (Postfix) with ESMTP id C08BA42730; Wed, 19 Aug 2020 16:29:41 +1000 (AEST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=hostfission.com; s=mail; t=1597818581; bh=Pu+NS9rLkZZPl1vLlUN9PbQd4yq0gCdDCk+RN+6r9LI=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=rXCT6QKaQfmrAUttJmZZXqUS/csZXUJT0dgDpfmz446bOZGv7EmHng2CEiErTQn34 LRFBNAqP1f+rvvbtwCq+niVDfyqIusDlBGZyQNZvLAFKVZav3D8I+Lm6MvWvqgLUD9 UqU3lOaLre4JWj+Ik+TM4T7bJi9IYNK90FXuyFXQ= Received: by moya.office.hostfission.com (Postfix, from userid 0) id B11E23A01BF; Wed, 19 Aug 2020 16:29:41 +1000 (AEST) From: Geoffrey McRae To: qemu-devel@nongnu.org Cc: Geoffrey McRae , kraxel@redhat.com Subject: [PATCH v5 1/1] audio/jack: fix use after free segfault Date: Wed, 19 Aug 2020 16:29:39 +1000 Message-Id: <20200819062940.52774-2-geoff@hostfission.com> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20200819062940.52774-1-geoff@hostfission.com> References: <20200819062940.52774-1-geoff@hostfission.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Received-SPF: none client-ip=139.99.139.48; envelope-from=root@moya.office.hostfission.com; helo=mail1.hostfission.com X-detected-operating-system: by eggs.gnu.org: First seen = 2020/08/18 23:36:32 X-ACL-Warn: Detected OS = Linux 3.11 and newer X-Spam_score_int: -27 X-Spam_score: -2.8 X-Spam_bar: -- X-Spam_report: (-2.8 / 5.0 requ) BAYES_00=-1.9, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_DNSWL_LOW=-0.7, RCVD_IN_MSPIKE_H4=-0.01, RCVD_IN_MSPIKE_WL=-0.01, SPF_HELO_NONE=0.001, SPF_NONE=0.001, URIBL_BLOCKED=0.001 autolearn=ham autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" This change registers a bottom handler to close the JACK client connection when a server shutdown signal is recieved. Without this libjack2 attempts to "clean up" old clients and causes a use after free segfault. Signed-off-by: Geoffrey McRae --- audio/jackaudio.c | 29 ++++++++++++++++++++--------- 1 file changed, 20 insertions(+), 9 deletions(-) diff --git a/audio/jackaudio.c b/audio/jackaudio.c index 72ed7c4929..b0da5cd00b 100644 --- a/audio/jackaudio.c +++ b/audio/jackaudio.c @@ -25,6 +25,7 @@ #include "qemu/osdep.h" #include "qemu/module.h" #include "qemu/atomic.h" +#include "qemu/main-loop.h" #include "qemu-common.h" #include "audio.h" @@ -63,6 +64,7 @@ typedef struct QJackClient { QJackState state; jack_client_t *client; jack_nframes_t freq; + QEMUBH *shutdown_bh; struct QJack *j; int nchannels; @@ -306,21 +308,27 @@ static int qjack_xrun(void *arg) return 0; } +static void qjack_shutdown_bh(void *opaque) +{ + QJackClient *c = (QJackClient *)opaque; + qjack_client_fini(c); +} + static void qjack_shutdown(void *arg) { QJackClient *c = (QJackClient *)arg; - c->state = QJACK_STATE_SHUTDOWN; + c->state = QJACK_STATE_SHUTDOWN; + qemu_bh_schedule(c->shutdown_bh); } static void qjack_client_recover(QJackClient *c) { - if (c->state == QJACK_STATE_SHUTDOWN) { - qjack_client_fini(c); + if (c->state != QJACK_STATE_DISCONNECTED) { + return; } /* packets is used simply to throttle this */ - if (c->state == QJACK_STATE_DISCONNECTED && - c->packets % 100 == 0) { + if (c->packets % 100 == 0) { /* if enabled then attempt to recover */ if (c->enabled) { @@ -417,6 +425,10 @@ static int qjack_client_init(QJackClient *c) options |= JackServerName; } + if (!c->shutdown_bh) { + c->shutdown_bh = qemu_bh_new(qjack_shutdown_bh, c); + } + c->client = jack_client_open(client_name, options, &status, c->opt->server_name); @@ -489,8 +501,6 @@ static int qjack_init_out(HWVoiceOut *hw, struct audsettings *as, QJackOut *jo = (QJackOut *)hw; Audiodev *dev = (Audiodev *)drv_opaque; - qjack_client_fini(&jo->c); - jo->c.out = true; jo->c.enabled = false; jo->c.nchannels = as->nchannels; @@ -525,8 +535,6 @@ static int qjack_init_in(HWVoiceIn *hw, struct audsettings *as, QJackIn *ji = (QJackIn *)hw; Audiodev *dev = (Audiodev *)drv_opaque; - qjack_client_fini(&ji->c); - ji->c.out = false; ji->c.enabled = false; ji->c.nchannels = as->nchannels; @@ -557,6 +565,8 @@ static int qjack_init_in(HWVoiceIn *hw, struct audsettings *as, static void qjack_client_fini(QJackClient *c) { + qemu_bh_cancel(c->shutdown_bh); + switch (c->state) { case QJACK_STATE_RUNNING: jack_deactivate(c->client); @@ -564,6 +574,7 @@ static void qjack_client_fini(QJackClient *c) case QJACK_STATE_SHUTDOWN: jack_client_close(c->client); + c->client = NULL; /* fallthrough */ case QJACK_STATE_DISCONNECTED: -- 2.20.1