Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) client-ip=2620:137:e000::1:20;
Date:   Wed, 23 Mar 2022 15:21:13 +0300
From:   Dan Carpenter <dan.carpenter@oracle.com>
To:     Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Cc:     Namjae Jeon <linkinjeon@kernel.org>,
        Sergey Senozhatsky <senozhatsky@chromium.org>,
        Steve French <sfrench@samba.org>,
        Hyunchul Lee <hyc.lee@gmail.com>, linux-kernel@vger.kernel.org,
        kernel-janitors@vger.kernel.org, linux-cifs@vger.kernel.org
Subject: Re: [PATCH] ksmbd: Remove a redundant zeroing of memory
Message-ID: <20220323122113.GC336@kadam>
References: <f8f1f383c4533a91a6025b1db5827ed6aaab002f.1647980983.git.christophe.jaillet@wanadoo.fr>
 <20220323065111.GO3293@kadam>
Content-Type: text/plain; charset=us-ascii
Content-Disposition: inline
In-Reply-To: <20220323065111.GO3293@kadam>
User-Agent: Mutt/1.9.4 (2018-02-28)
MIME-Version: 1.0
X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1
X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?eamSCNfr6PLSdlMXohX2aqBhXshVSjmHcQ9F0xAo/zsGgSvH/PV3aoCfphAg?=
 =?us-ascii?Q?KU2uqa1Vif63k79V4wVBeq3kLHNPqJq2pGpcsjmglU96RNlKfKZHI6B/v9j/?=
 =?us-ascii?Q?Xz3Nm7ESzlr9K2VtKNqdgwDcCXb8n+pbIITyx+Dh31lDhV0D2i1LHot0IiRD?=
 =?us-ascii?Q?NRlm0cnFjQE451WQVsTkx4/8efBCc0TJNRSqjR3kcgKrjfi064gkI7uYWNpe?=
 =?us-ascii?Q?jMm9DdXevMlmsIMgQ+gdwVhqXJ+uc5vEmLOR0PW1NVS1v/4GFaXVst30RN3o?=
 =?us-ascii?Q?zljqcJWgj1Jg8ZM6mtOSsGYTSycVjBZE7QihKpw0wUAE/dpJ6b7P7FUqYwxT?=
 =?us-ascii?Q?iiTJpy2ZLuql0aLXAR+uPnWjKUz1AK4WMR5888RhNG8I+SqgKscppAUWlf8K?=
 =?us-ascii?Q?/EUC641HUJhH1fyDFjLDDDQCOWtyHIpeXk90YDY7OOhemYf1IKyBrAF6kyCI?=
 =?us-ascii?Q?YQMSUMADNB6pBLjUhqMoyQQFuncb5TAfCf+5Ok3cjyi6wAQXlYi2O9e/6nYb?=
 =?us-ascii?Q?tq9zzvGfn/zR+cuL4+ctx3UKC9LBXRwNTJKc99j87/cZtX71zngksYvf++k/?=
 =?us-ascii?Q?4IOZU9nme/1a2/nS6duat0NgLukr6dJbc1fEk4tJGDZ6cAMgdRnsWt5gbfNA?=
 =?us-ascii?Q?17s0SVMrPe3m5o0SlLwPdiBfu2y1EcIdveQ423U7yeSHdLZL9Ndx6YvhVSCD?=
 =?us-ascii?Q?M5NovVJ3mO3Hw3XWh0gwpYuzAUmhjDOtkCUTY7WddgmxoPBMK3aKl1Ny6b9J?=
 =?us-ascii?Q?Obo9McY2G43LTAjYC1Lf/HX+ZVbsi3vIo6N5vept5I3DfV2pwIxSRpvZXdmX?=
 =?us-ascii?Q?F3xHIsg7+wSdQ2Mng68ygR1XmL58pUh7ncGsotrqNlnoRln8xtSeSVP4ecvT?=
 =?us-ascii?Q?wzCjxHa1sil/0i2RZd+Bu4Zul7BHP8vnE9ew2fPfMUX85SQEBQKP3YPbw9lU?=
 =?us-ascii?Q?g7Jg9UqTtsUBLiz9eVfa/reoJJ1ekzys8iKK1Bh24oO7FCs9ddihF/qv31qa?=
 =?us-ascii?Q?iZSEVxixxNcIbGBxESy1psTamDdwU7ibKctwtQ29MlFs9eQZjQldrkVc8OK9?=
 =?us-ascii?Q?jseNkYaevKOS4HT43Ot5PDmdWn89ZmEwALQfNEafkzYkHH7zoK93eBysJVqq?=
 =?us-ascii?Q?gjnJUVMPnsPYrzqrPWUY+8NKdxSBWSvafR00e8IAF3JStcLqZTZDnQ9kXFDA?=
 =?us-ascii?Q?k8x0v7KD9JjwD/74vOtd3kCZKrb8hIZMym7+vXxcDgyPUM45WO6ZTTqfE4eD?=
 =?us-ascii?Q?nNsLLtFviopPX5BWSeH5QyXjvgf+cCgRaLaaNc6ebDuE+ZAKXzb3Oz5K6HZJ?=
 =?us-ascii?Q?HruxF+Tbk9z37z8CXLvQwnvmHU1XDo4QSRvAaYn55Mdz7D0dtTtuz4diFZh1?=
 =?us-ascii?Q?hzcSOgDbRsuEgKCb4JeZzEdotuHfB51jl3q8KnMKpgHLzSypqWTMk2Jd3pJE?=
 =?us-ascii?Q?tGdXXzMaCTDW64y0WkGvtzULhTB6VqFVE5C27Eyvn822fezp7EgXNw=3D=3D?=
X-OriginatorOrg: oracle.com
X-MS-Exchange-CrossTenant-Network-Message-Id: b450f3d1-ff2e-4f89-299c-08da0cc7aace
X-MS-Exchange-CrossTenant-AuthSource: MWHPR1001MB2365.namprd10.prod.outlook.com
X-MS-Exchange-CrossTenant-AuthAs: Internal
X-MS-Exchange-CrossTenant-OriginalArrivalTime: 23 Mar 2022 12:21:33.2353
 (UTC)
X-MS-Exchange-CrossTenant-FromEntityHeader: Hosted
X-MS-Exchange-CrossTenant-Id: 4e2c6054-71cb-48f1-bd6c-3a9705aca71b
X-MS-Exchange-CrossTenant-MailboxType: HOSTED
X-MS-Exchange-CrossTenant-UserPrincipalName: kd19Eh7TeiBnoOSfMy48SM+iMxShn7YkQ8cHfqc1m/nUjs0z7uqTuSS3NIJEHD3c4Lz64X6T6KKeEsDu0mfJEERCS03udDzw4CEwmfrv+yc=
X-MS-Exchange-Transport-CrossTenantHeadersStamped: CH2PR10MB4069
X-Proofpoint-Virus-Version: vendor=nai engine=6300 definitions=10294 signatures=694350
X-Proofpoint-Spam-Details: rule=notspam policy=default score=0 adultscore=0 suspectscore=0 spamscore=0
 mlxlogscore=999 phishscore=0 bulkscore=0 malwarescore=0 mlxscore=0
 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2202240000
 definitions=main-2203230071
X-Proofpoint-GUID: 7HffZtGyAhl3AaSNF0u_51RYiAH459WF
X-Proofpoint-ORIG-GUID: 7HffZtGyAhl3AaSNF0u_51RYiAH459WF
X-Spam-Status: No, score=-2.8 required=5.0 tests=BAYES_00,DKIM_SIGNED,
        DKIM_VALID,DKIM_VALID_AU,DKIM_VALID_EF,RCVD_IN_DNSWL_LOW,
        RCVD_IN_MSPIKE_H5,RCVD_IN_MSPIKE_WL,SPF_HELO_NONE,SPF_NONE,
        T_SCC_BODY_TEXT_LINE autolearn=ham autolearn_force=no version=3.4.6
X-Spam-Checker-Version: SpamAssassin 3.4.6 (2021-04-09) on
        lindbergh.monkeyblade.net
Precedence: bulk
List-ID: <linux-kernel.vger.kernel.org>
X-Mailing-List: linux-kernel@vger.kernel.org

On Wed, Mar 23, 2022 at 09:51:11AM +0300, Dan Carpenter wrote:
> On Tue, Mar 22, 2022 at 09:29:51PM +0100, Christophe JAILLET wrote:
> > fill_transform_hdr() already call memset(0) on its 1st argument, so there
> > is no need to clear it explicitly before calling this function.
> > 
> > Use kmalloc() instead of kzalloc() to save a few cycles.
> > 
> > Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
> > ---
> > Alternatively, fill_transform_hdr() has only one caller. So its memset()
> > could be removed instead and this kzalloc() left as is.
> > ---
> >  fs/ksmbd/smb2pdu.c | 2 +-
> >  1 file changed, 1 insertion(+), 1 deletion(-)
> > 
> > diff --git a/fs/ksmbd/smb2pdu.c b/fs/ksmbd/smb2pdu.c
> > index bcb98109bac9..0e4f819e5859 100644
> > --- a/fs/ksmbd/smb2pdu.c
> > +++ b/fs/ksmbd/smb2pdu.c
> > @@ -8434,7 +8434,7 @@ int smb3_encrypt_resp(struct ksmbd_work *work)
> >  	if (ARRAY_SIZE(iov) < rq_nvec)
> >  		return -ENOMEM;
> >  
> > -	work->tr_buf = kzalloc(sizeof(struct smb2_transform_hdr) + 4, GFP_KERNEL);
> > +	work->tr_buf = kmalloc(sizeof(struct smb2_transform_hdr) + 4, GFP_KERNEL);
>                                                                  ^^^
> fill_transform_hdr() does not clear the last 4 bytes.
> 

Oops.  I was looking at the wrong fill_transform_hdr() from smb2ops.c
instead of smb2pdu.c.  Sorry!

regards,
dan carpenter