Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) client-ip=23.128.96.18;
Date:   Tue, 28 Sep 2021 16:52:07 +0300
From:   Dan Carpenter <dan.carpenter@oracle.com>
To:     "Russell King (Oracle)" <linux@armlinux.org.uk>
Cc:     Pavel Skripkin <paskripkin@gmail.com>,
        Yanfei Xu <yanfei.xu@windriver.com>,
        Bartosz Golaszewski <bgolaszewski@baylibre.com>,
        andrew@lunn.ch, hkallweit1@gmail.com, davem@davemloft.net,
        kuba@kernel.org, p.zabel@pengutronix.de,
        syzbot+398e7dc692ddbbb4cfec@syzkaller.appspotmail.com,
        linux-kernel@vger.kernel.org, netdev@vger.kernel.org,
        Dongliang Mu <mudongliangabcd@gmail.com>
Subject: Re: [PATCH] net: mdiobus: Fix memory leak in __mdiobus_register
Message-ID: <20210928135207.GP2083@kadam>
References: <20210928085549.GA6559@kili>
 <20210928092657.GI2048@kadam>
 <6f90fa0f-6d3b-0ca7-e894-eb971b3b69fa@gmail.com>
 <20210928103908.GJ2048@kadam>
 <63b18426-c39e-d898-08fb-8bfd05b7be9e@gmail.com>
 <20210928105943.GL2083@kadam>
 <283d01f0-d5eb-914e-1bd2-baae0420073c@gmail.com>
 <f587da4b-09dd-4c32-4ee4-5ec8b9ad792f@gmail.com>
 <20210928113055.GN2083@kadam>
 <YVMRWNDZDUOvQjHL@shell.armlinux.org.uk>
Content-Type: text/plain; charset=us-ascii
Content-Disposition: inline
In-Reply-To: <YVMRWNDZDUOvQjHL@shell.armlinux.org.uk>
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?IxAWPbf8ef8u2rNNVK7Zr7mdzWEqWtbKV+uotij3bCl3ZdKGJWJcbgjhtyxp?=
 =?us-ascii?Q?oiVrWWgNtY63y+ERvf8keDZcmUowg6ytEv3gKcOM4QVKt+QWfiDjqElrVbYE?=
 =?us-ascii?Q?w0+vOrXhyESMwEuKaM6eYGHRFEECPx8sVNy3RneEcl8oN8QH56d4ZStJQCcL?=
 =?us-ascii?Q?Owh4Xi4V1d+Kf1brDW1VORJ/iwfI6NhqXKXWM1UVBIj6zpT1qHdQYaQqr373?=
 =?us-ascii?Q?4apoi0FiWRVCtYKyOq5AGN4a6mnZfNsNSLpZGN3Z9L9WD1bnlgS0p4Zoc27k?=
 =?us-ascii?Q?L6Lqyd9h6V/duDPgrwZ8B6ra3B356EN6ME6HrKRAAyZyqk06eZLzMw8Tw3p3?=
 =?us-ascii?Q?yYD0hBt5FCMGVb4I8vUXPaqsHDMki8kJOAmnVNfYDxNSzDJmRI5RIgFdVvJh?=
 =?us-ascii?Q?lIAuNyfD+bc46AnBN8xMRXgikcAPa+NxGXs2M83xdXaG4dbIFwuyWimaZmYf?=
 =?us-ascii?Q?uQHyCI3/NHYs0Rweb6YITL9PPX0attNLIVvQxHGMmCAVPu5FuPuMRLwvBhKb?=
 =?us-ascii?Q?KQU7gpGusssoiXJsYoaRq/1f0Jal3M1EOcdUb4Cey+do1UMF0MvmOU5JtjsY?=
 =?us-ascii?Q?hza+HZ0sYo7N+aALz4vcDeXxi/bslu25QwUwWW2HpnlJOOu/LNOFIrcIv2jW?=
 =?us-ascii?Q?xiiOU78yFPD5dxbdCeQTlFZ7WNyK2GZrMDrV590n0dC9obDqzCmARKUwHjGO?=
 =?us-ascii?Q?KfK0sIdlpmn9uaVJh1J1WoM7EJSOYUgmlDpERWiJ7TKzrw3YAdIoI6ASLnN4?=
 =?us-ascii?Q?Ww9KntsfHFTcJ3un0cHRiyK8LyjQfO2loLhY2ZD/pV3LIIzw86I+DF8pAxhc?=
 =?us-ascii?Q?sxLV547FTD3Bq4Zr1MZDdovahtC0JAO9aDU45ZJd2p5KQiXx6X1cuLcMp0xO?=
 =?us-ascii?Q?KH3Jx2IZ2XVajUcybR36MjM8xH4Wfblsp95IXKFtLjjrvnt4UTm//TtNs7XA?=
 =?us-ascii?Q?PsXpm1PpT49J5Itl4yNlQ3XgEj4NziIe6H/J556UPeDsklW8y8bLfq8Mbu2f?=
 =?us-ascii?Q?Ai2pvo5KxCgE/4RjtE2JKDcPZw2To1Sb44geu7mkT2KPDx5Vex7TEXGu6Eq7?=
 =?us-ascii?Q?qGU5gpyBEBuam+d0H90Sn1jweJZEJP2CFCxQ78T9WMg7tYt5s8RW2//UyuF+?=
 =?us-ascii?Q?x43vOLJoUkDf0paLiT/g3HkdL0GT4bs2Rn6Fn30L9+K9Tawt+3a1TARa3MvX?=
 =?us-ascii?Q?Mvuz9/ckNgGvsHbEi4G53aBStcz212tW+sp8F7S5m5SUZlQjPQVtWXp281qQ?=
 =?us-ascii?Q?nF3LMNhOligPqtrpPUI3nOfZAqAejytO4zldFb5H+4bS7rTvSKOYWDpSNuGE?=
 =?us-ascii?Q?AdH4+0xH5pEVhbNcLRP4Gd5O?=
X-OriginatorOrg: oracle.com
X-MS-Exchange-CrossTenant-Network-Message-Id: 0db8dce2-8ecc-41b2-5ff6-08d9828733f1
X-MS-Exchange-CrossTenant-AuthSource: MWHPR1001MB2365.namprd10.prod.outlook.com
X-MS-Exchange-CrossTenant-AuthAs: Internal
X-MS-Exchange-CrossTenant-OriginalArrivalTime: 28 Sep 2021 13:52:25.8445
 (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: 51/lgCg1ZPc7CZcQQf454Z7pBS8XTqCmr2Ykkw/x9BqBCV9sEoyFMUgAkvl+7njzxxDIP18OFRgsWgFyJ+Sz2ZSAxxFFg8XkWRCTi6qH4ps=
X-MS-Exchange-Transport-CrossTenantHeadersStamped: CO6PR10MB5459
X-Proofpoint-Virus-Version: vendor=nai engine=6300 definitions=10120 signatures=668682
X-Proofpoint-Spam-Details: rule=notspam policy=default score=0 malwarescore=0 suspectscore=0
 spamscore=0 bulkscore=0 mlxlogscore=999 phishscore=0 adultscore=0
 mlxscore=0 classifier=spam adjust=0 reason=mlx scancount=1
 engine=8.12.0-2109230001 definitions=main-2109280079
X-Proofpoint-ORIG-GUID: 4u97H2vTXNqZhccK5AN1zwEvjwc3A1vC
X-Proofpoint-GUID: 4u97H2vTXNqZhccK5AN1zwEvjwc3A1vC
Precedence: bulk
List-ID: <linux-kernel.vger.kernel.org>
X-Mailing-List: linux-kernel@vger.kernel.org

On Tue, Sep 28, 2021 at 01:58:00PM +0100, Russell King (Oracle) wrote:
>
> This thread seems to be getting out of hand.

The thread was closed.  We need to revert Yanfei's patch and apply
Pavel's patch.  He's going to resend.

> So, I would suggest a simple fix is to set bus->state to
> MDIOBUS_UNREGISTERED immediately _after_ the successful
> device_register().

Not after.  It has to be set to MDIOBUS_UNREGISTERED if device_register()
fails, otherwise there will still be a leak.

Adding a comment is a good idea.

regards,
dan carpenter