From mboxrd@z Thu Jan 1 00:00:00 1970 From: Tejun Heo Subject: [PATCH 3/4] blkcg: fix blkcg->css ref leak in __blkg_lookup_create() Date: Thu, 19 Apr 2012 16:29:23 -0700 Message-ID: <1334878164-24788-4-git-send-email-tj@kernel.org> References: <1334878164-24788-1-git-send-email-tj@kernel.org> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20120113; h=sender:from:to:cc:subject:date:message-id:x-mailer:in-reply-to :references; bh=gWip8WwVDKYMvuR0kgiPzY07opaWvDhtYvyLB9tJ3g8=; b=0mvfxoIOjQ0Z7M5e7h4BvhxD+/5tfq+1LNLhLGGtJxnLq6PZgjBg858uXbu4GaQoT2 uTexiODLp8U/ynxOvQkqX/hr5qJQZWWbjiIMzd0Tj+rqHRGNH7CDGkFWVQKyTSK+p0Gp LZihD1SmAK3W0+xiXsDMzXIGrgDM0AOvmgIB7PyedJhoQ2JFHaTToKndcvPWWzzQnxUF VlZZs6MWksDuTU/lILLgIsgEyuAJs3tVTSMncqnuWyDdGspfNwnFADHpy+1TzLKEtv77 QUKAsENvhvaPc3/zWC6OBcqD+UfG0l3MoY3cjsSuqTwTcDpJc9bRMs7ZMhER6YLRs8gy CoAA== In-Reply-To: <1334878164-24788-1-git-send-email-tj-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org> List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: containers-bounces-cunTk1MwBs9QetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA@public.gmane.org Errors-To: containers-bounces-cunTk1MwBs9QetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA@public.gmane.org To: axboe-tSWWG44O7X1aa/9Udqfwiw@public.gmane.org Cc: ctalbott-hpIqsD4AKlfQT0dZR+AlfA@public.gmane.org, rni-hpIqsD4AKlfQT0dZR+AlfA@public.gmane.org, containers-cunTk1MwBs9QetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA@public.gmane.org, linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, Tejun Heo , cgroups-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, vgoyal-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org __blkg_lookup_create() leaked blkcg->css ref if blkg allocation failed. Fix it. Signed-off-by: Tejun Heo Cc: Vivek Goyal --- block/blk-cgroup.c | 19 +++++++++---------- 1 files changed, 9 insertions(+), 10 deletions(-) diff --git a/block/blk-cgroup.c b/block/blk-cgroup.c index 8228385..30a7a9c 100644 --- a/block/blk-cgroup.c +++ b/block/blk-cgroup.c @@ -174,6 +174,7 @@ static struct blkcg_gq *__blkg_lookup_create(struct blkcg *blkcg, __releases(q->queue_lock) __acquires(q->queue_lock) { struct blkcg_gq *blkg; + int ret; WARN_ON_ONCE(!rcu_read_lock_held()); lockdep_assert_held(q->queue_lock); @@ -186,24 +187,22 @@ static struct blkcg_gq *__blkg_lookup_create(struct blkcg *blkcg, if (!css_tryget(&blkcg->css)) return ERR_PTR(-EINVAL); - /* - * Allocate and initialize. - */ + /* allocate */ + ret = -ENOMEM; blkg = blkg_alloc(blkcg, q); - - /* did alloc fail? */ - if (unlikely(!blkg)) { - blkg = ERR_PTR(-ENOMEM); - goto out; - } + if (unlikely(!blkg)) + goto err_put; /* insert */ spin_lock(&blkcg->lock); hlist_add_head_rcu(&blkg->blkcg_node, &blkcg->blkg_list); list_add(&blkg->q_node, &q->blkg_list); spin_unlock(&blkcg->lock); -out: return blkg; + +err_put: + css_put(&blkcg->css); + return ERR_PTR(ret); } struct blkcg_gq *blkg_lookup_create(struct blkcg *blkcg, -- 1.7.7.3 From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756276Ab2DSX3h (ORCPT ); Thu, 19 Apr 2012 19:29:37 -0400 Received: from mail-pb0-f46.google.com ([209.85.160.46]:42641 "EHLO mail-pb0-f46.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756107Ab2DSX3g (ORCPT ); Thu, 19 Apr 2012 19:29:36 -0400 From: Tejun Heo To: axboe@kernel.dk Cc: vgoyal@redhat.com, ctalbott@google.com, rni@google.com, cgroups@vger.kernel.org, containers@lists.linux-foundation.org, linux-kernel@vger.kernel.org, Tejun Heo Subject: [PATCH 3/4] blkcg: fix blkcg->css ref leak in __blkg_lookup_create() Date: Thu, 19 Apr 2012 16:29:23 -0700 Message-Id: <1334878164-24788-4-git-send-email-tj@kernel.org> X-Mailer: git-send-email 1.7.7.3 In-Reply-To: <1334878164-24788-1-git-send-email-tj@kernel.org> References: <1334878164-24788-1-git-send-email-tj@kernel.org> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org __blkg_lookup_create() leaked blkcg->css ref if blkg allocation failed. Fix it. Signed-off-by: Tejun Heo Cc: Vivek Goyal --- block/blk-cgroup.c | 19 +++++++++---------- 1 files changed, 9 insertions(+), 10 deletions(-) diff --git a/block/blk-cgroup.c b/block/blk-cgroup.c index 8228385..30a7a9c 100644 --- a/block/blk-cgroup.c +++ b/block/blk-cgroup.c @@ -174,6 +174,7 @@ static struct blkcg_gq *__blkg_lookup_create(struct blkcg *blkcg, __releases(q->queue_lock) __acquires(q->queue_lock) { struct blkcg_gq *blkg; + int ret; WARN_ON_ONCE(!rcu_read_lock_held()); lockdep_assert_held(q->queue_lock); @@ -186,24 +187,22 @@ static struct blkcg_gq *__blkg_lookup_create(struct blkcg *blkcg, if (!css_tryget(&blkcg->css)) return ERR_PTR(-EINVAL); - /* - * Allocate and initialize. - */ + /* allocate */ + ret = -ENOMEM; blkg = blkg_alloc(blkcg, q); - - /* did alloc fail? */ - if (unlikely(!blkg)) { - blkg = ERR_PTR(-ENOMEM); - goto out; - } + if (unlikely(!blkg)) + goto err_put; /* insert */ spin_lock(&blkcg->lock); hlist_add_head_rcu(&blkg->blkcg_node, &blkcg->blkg_list); list_add(&blkg->q_node, &q->blkg_list); spin_unlock(&blkcg->lock); -out: return blkg; + +err_put: + css_put(&blkcg->css); + return ERR_PTR(ret); } struct blkcg_gq *blkg_lookup_create(struct blkcg *blkcg, -- 1.7.7.3