From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751548AbZJQGeR (ORCPT ); Sat, 17 Oct 2009 02:34:17 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751284AbZJQGeQ (ORCPT ); Sat, 17 Oct 2009 02:34:16 -0400 Received: from mgw1.diku.dk ([130.225.96.91]:59128 "EHLO mgw1.diku.dk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751190AbZJQGeP (ORCPT ); Sat, 17 Oct 2009 02:34:15 -0400 Date: Sat, 17 Oct 2009 08:34:18 +0200 (CEST) From: Julia Lawall To: linux-kernel@vger.kernel.org, kernel-janitors@vger.kernel.org Subject: [PATCH 4/14] drivers/message: Move dereference after NULL test Message-ID: MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Julia Lawall If the NULL test on dev->i2o_dev or i2o_dev is needed, then the dereference should be after the NULL test. A simplified version of the semantic match that detects this problem is as follows (http://coccinelle.lip6.fr/): // @match exists@ expression x, E; identifier fld; @@ * x->fld ... when != \(x = E\|&x\) * x == NULL // Signed-off-by: Julia Lawall --- drivers/message/i2o/i2o_block.c | 3 ++- drivers/message/i2o/i2o_scsi.c | 3 +-- 2 files changed, 3 insertions(+), 3 deletions(-) diff --git a/drivers/message/i2o/i2o_block.c b/drivers/message/i2o/i2o_block.c index d505b68..67da0aa 100644 --- a/drivers/message/i2o/i2o_block.c +++ b/drivers/message/i2o/i2o_block.c @@ -711,7 +711,7 @@ static int i2o_block_transfer(struct request *req) { struct i2o_block_device *dev = req->rq_disk->private_data; struct i2o_controller *c; - u32 tid = dev->i2o_dev->lct_data.tid; + u32 tid; struct i2o_message *msg; u32 *mptr; struct i2o_block_request *ireq = req->special; @@ -727,6 +727,7 @@ static int i2o_block_transfer(struct request *req) goto exit; } + tid = dev->i2o_dev->lct_data.tid; c = dev->i2o_dev->iop; msg = i2o_msg_get(c); diff --git a/drivers/message/i2o/i2o_scsi.c b/drivers/message/i2o/i2o_scsi.c index 3d45817..ea6b219 100644 --- a/drivers/message/i2o/i2o_scsi.c +++ b/drivers/message/i2o/i2o_scsi.c @@ -528,7 +528,6 @@ static int i2o_scsi_queuecommand(struct scsi_cmnd *SCpnt, * Do the incoming paperwork */ i2o_dev = SCpnt->device->hostdata; - c = i2o_dev->iop; SCpnt->scsi_done = done; @@ -538,7 +537,7 @@ static int i2o_scsi_queuecommand(struct scsi_cmnd *SCpnt, done(SCpnt); goto exit; } - + c = i2o_dev->iop; tid = i2o_dev->lct_data.tid; osm_debug("qcmd: Tid = %03x\n", tid);