From mboxrd@z Thu Jan 1 00:00:00 1970 From: tristan Date: Fri, 10 Sep 2010 10:31:01 +0800 Subject: [Ocfs2-devel] [PATCH 1/1] Ocfs2: Handle empty list in lockres_seq_start() for dlmdebug.c In-Reply-To: <4C8995A1.3010700@oracle.com> References: <1284084993-7767-1-git-send-email-tristan.ye@oracle.com> <4C8995A1.3010700@oracle.com> Message-ID: <4C899865.6010909@oracle.com> List-Id: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: ocfs2-devel@oss.oracle.com Sunil Mushran wrote: > Signed-off-by: Sunil Mushran > > I am assuming you have tested it. ;) Sure, both in local mode by creating a user dlm domain, and in a cluster. > > > On 09/09/2010 07:16 PM, Tristan Ye wrote: >> This patch tries to handle the case in which list >> 'dlm->tracking_list' is >> empty, to avoid accessing an invalid pointer. It fixes the following >> oops: >> >> http://oss.oracle.com/bugzilla/show_bug.cgi?id=1287 >> >> Signed-off-by: Tristan Ye >> --- >> fs/ocfs2/dlm/dlmdebug.c | 9 ++++++++- >> 1 files changed, 8 insertions(+), 1 deletions(-) >> >> diff --git a/fs/ocfs2/dlm/dlmdebug.c b/fs/ocfs2/dlm/dlmdebug.c >> index 5efdd37..901ca52 100644 >> --- a/fs/ocfs2/dlm/dlmdebug.c >> +++ b/fs/ocfs2/dlm/dlmdebug.c >> @@ -636,8 +636,14 @@ static void *lockres_seq_start(struct seq_file >> *m, loff_t *pos) >> spin_lock(&dlm->track_lock); >> if (oldres) >> track_list =&oldres->tracking; >> - else >> + else { >> track_list =&dlm->tracking_list; >> + if (list_empty(track_list)) { >> + dl = NULL; >> + spin_unlock(&dlm->track_lock); >> + goto bail; >> + } >> + } >> >> list_for_each_entry(res, track_list, tracking) { >> if (&res->tracking ==&dlm->tracking_list) >> @@ -660,6 +666,7 @@ static void *lockres_seq_start(struct seq_file >> *m, loff_t *pos) >> } else >> dl = NULL; >> >> +bail: >> /* passed to seq_show */ >> return dl; >> } >> >