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=-17.2 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER,INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED,USER_AGENT_SANE_1 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 4AD91C4361B for ; Fri, 18 Dec 2020 00:03:41 +0000 (UTC) Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [216.205.24.124]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id A26A823A58 for ; Fri, 18 Dec 2020 00:03:40 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org A26A823A58 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=redhat.com Authentication-Results: mail.kernel.org; spf=tempfail smtp.mailfrom=dm-devel-bounces@redhat.com DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1608249819; h=from:from:sender:sender:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references:list-id:list-help: list-unsubscribe:list-subscribe:list-post; bh=G1cNqixqdJLFIMC1cdDNZ2Q+SU0gT971/ZgyLDf+DCc=; b=Dh1JFvbvTs+EfdCVjbKitXvOOmVQQvINxbXVBZJcl/ShgjnvSH7ANFSXRSghTr3q8jfuaE C04acc84e3IblPVQLjUIgkdm7G3POXh+nBH8vZzeESHxaK2/SxOuGAnzktScqJLwTqFUd/ bK2lLkZWHgHkgEIIFKU4kusV+1f/gY8= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-331-dW6iXi-OPRWUCi5aRKjOjQ-1; Thu, 17 Dec 2020 19:03:36 -0500 X-MC-Unique: dW6iXi-OPRWUCi5aRKjOjQ-1 Received: from smtp.corp.redhat.com (int-mx08.intmail.prod.int.phx2.redhat.com [10.5.11.23]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 651A380364F; Fri, 18 Dec 2020 00:03:16 +0000 (UTC) Received: from colo-mx.corp.redhat.com (colo-mx02.intmail.prod.int.phx2.redhat.com [10.5.11.21]) by smtp.corp.redhat.com (Postfix) with ESMTPS id 0CF8B19D9F; Fri, 18 Dec 2020 00:03:16 +0000 (UTC) Received: from lists01.pubmisc.prod.ext.phx2.redhat.com (lists01.pubmisc.prod.ext.phx2.redhat.com [10.5.19.33]) by colo-mx.corp.redhat.com (Postfix) with ESMTP id 57F6A4BB7B; Fri, 18 Dec 2020 00:03:15 +0000 (UTC) Received: from smtp.corp.redhat.com (int-mx05.intmail.prod.int.phx2.redhat.com [10.5.11.15]) by lists01.pubmisc.prod.ext.phx2.redhat.com (8.13.8/8.13.8) with ESMTP id 0BI03Dh1015822 for ; Thu, 17 Dec 2020 19:03:13 -0500 Received: by smtp.corp.redhat.com (Postfix) id 3D1BE63633; Fri, 18 Dec 2020 00:03:13 +0000 (UTC) Received: from octiron.msp.redhat.com (octiron.msp.redhat.com [10.15.80.209]) by smtp.corp.redhat.com (Postfix) with ESMTPS id 24CC45D737; Fri, 18 Dec 2020 00:03:13 +0000 (UTC) Received: from octiron.msp.redhat.com (localhost.localdomain [127.0.0.1]) by octiron.msp.redhat.com (8.14.9/8.14.9) with ESMTP id 0BI03Bgp002514; Thu, 17 Dec 2020 18:03:11 -0600 Received: (from bmarzins@localhost) by octiron.msp.redhat.com (8.14.9/8.14.9/Submit) id 0BI03BWM002512; Thu, 17 Dec 2020 18:03:11 -0600 Date: Thu, 17 Dec 2020 18:03:11 -0600 From: Benjamin Marzinski To: mwilck@suse.com Message-ID: <20201218000311.GD3103@octiron.msp.redhat.com> References: <20201217110018.3347-1-mwilck@suse.com> <20201217110018.3347-3-mwilck@suse.com> MIME-Version: 1.0 In-Reply-To: <20201217110018.3347-3-mwilck@suse.com> User-Agent: Mutt/1.5.23 (2014-03-12) X-Scanned-By: MIMEDefang 2.79 on 10.5.11.15 X-loop: dm-devel@redhat.com Cc: dm-devel@redhat.com Subject: Re: [dm-devel] [PATCH 2/7] libmultipath: protect logarea with logq_lock X-BeenThere: dm-devel@redhat.com X-Mailman-Version: 2.1.12 Precedence: junk List-Id: device-mapper development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: dm-devel-bounces@redhat.com Errors-To: dm-devel-bounces@redhat.com X-Scanned-By: MIMEDefang 2.84 on 10.5.11.23 Authentication-Results: relay.mimecast.com; auth=pass smtp.auth=CUSA124A263 smtp.mailfrom=dm-devel-bounces@redhat.com X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Content-Disposition: inline Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit On Thu, Dec 17, 2020 at 12:00:13PM +0100, mwilck@suse.com wrote: > From: Martin Wilck > > Make sure the global logarea (la) is only allocated and freed > hile holding logq_lock. This avoids invalid memory access. > > This patch makes free_logarea() static. libmultipath.version > is unchanged, as free_logarea() wasn't exported anyway. > > Signed-off-by: Martin Wilck > --- > libmultipath/log.c | 32 +++++++++++++++++++++++--------- > libmultipath/log.h | 1 - > 2 files changed, 23 insertions(+), 10 deletions(-) > > diff --git a/libmultipath/log.c b/libmultipath/log.c > index 7f33787..95c8f01 100644 > --- a/libmultipath/log.c > +++ b/libmultipath/log.c > @@ -77,16 +77,23 @@ static int logarea_init (int size) > > int log_init(char *program_name, int size) > { > + int ret = 1; > + > logdbg(stderr,"enter log_init\n"); > + > + pthread_mutex_lock(&logq_lock); > + pthread_cleanup_push(cleanup_mutex, &logq_lock); > + > openlog(program_name, 0, LOG_DAEMON); > + if (!la) > + ret = logarea_init(size); > > - if (logarea_init(size)) > - return 1; > + pthread_cleanup_pop(1); > > - return 0; > + return ret; > } > > -void free_logarea (void) > +static void free_logarea (void) > { > FREE(la->start); > FREE(la->buff); I realize that the log area can only be freed by log_close(), which is called when mulitpathd exits, but it would be nice to have la set to NULL it's freed, just to make it obvious that that there can't be double-frees there. However, the code is clearly correct, so Reviewed-by: Benjamin Marzinski > @@ -96,9 +103,14 @@ void free_logarea (void) > > void log_close (void) > { > - free_logarea(); > + pthread_mutex_lock(&logq_lock); > + pthread_cleanup_push(cleanup_mutex, &logq_lock); > + > + if (la) > + free_logarea(); > closelog(); > > + pthread_cleanup_pop(1); > return; > } > > @@ -175,11 +187,12 @@ static int _log_enqueue(int prio, const char * fmt, va_list ap) > > int log_enqueue(int prio, const char *fmt, va_list ap) > { > - int ret; > + int ret = 1; > > pthread_mutex_lock(&logq_lock); > pthread_cleanup_push(cleanup_mutex, &logq_lock); > - ret = _log_enqueue(prio, fmt, ap); > + if (la) > + ret = _log_enqueue(prio, fmt, ap); > pthread_cleanup_pop(1); > return ret; > } > @@ -215,11 +228,12 @@ static int _log_dequeue(void *buff) > > int log_dequeue(void *buff) > { > - int ret; > + int ret = 1; > > pthread_mutex_lock(&logq_lock); > pthread_cleanup_push(cleanup_mutex, &logq_lock); > - ret = _log_dequeue(buff); > + if (la) > + ret = _log_dequeue(buff); > pthread_cleanup_pop(1); > return ret; > } > diff --git a/libmultipath/log.h b/libmultipath/log.h > index d2448f6..fa224e4 100644 > --- a/libmultipath/log.h > +++ b/libmultipath/log.h > @@ -39,6 +39,5 @@ int log_enqueue (int prio, const char * fmt, va_list ap) > int log_dequeue (void *); > void log_syslog (void *); > void dump_logmsg (void *); > -void free_logarea (void); > > #endif /* LOG_H */ > -- > 2.29.0 -- dm-devel mailing list dm-devel@redhat.com https://www.redhat.com/mailman/listinfo/dm-devel