From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Niu Yawei , Jan Kara Subject: [PATCH 3.15 026/109] quota: missing lock in dqcache_shrink_scan() Date: Sat, 26 Jul 2014 12:01:48 -0700 Message-Id: <20140726190224.618930283@linuxfoundation.org> In-Reply-To: <20140726190223.834037485@linuxfoundation.org> References: <20140726190223.834037485@linuxfoundation.org> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: 3.15-stable review patch. If anyone has any objections, please let me know. ------------------ From: Niu Yawei commit d68aab6b8f572406aa93b45ef6483934dd3b54a6 upstream. Commit 1ab6c4997e04 (fs: convert fs shrinkers to new scan/count API) accidentally removed locking from quota shrinker. Fix it - dqcache_shrink_scan() should use dq_list_lock to protect the scan on free_dquots list. Fixes: 1ab6c4997e04a00c50c6d786c2f046adc0d1f5de Signed-off-by: Niu Yawei Signed-off-by: Jan Kara Signed-off-by: Greg Kroah-Hartman --- fs/quota/dquot.c | 2 ++ 1 file changed, 2 insertions(+) --- a/fs/quota/dquot.c +++ b/fs/quota/dquot.c @@ -702,6 +702,7 @@ dqcache_shrink_scan(struct shrinker *shr struct dquot *dquot; unsigned long freed = 0; + spin_lock(&dq_list_lock); head = free_dquots.prev; while (head != &free_dquots && sc->nr_to_scan) { dquot = list_entry(head, struct dquot, dq_free); @@ -713,6 +714,7 @@ dqcache_shrink_scan(struct shrinker *shr freed++; head = free_dquots.prev; } + spin_unlock(&dq_list_lock); return freed; }