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:   Fri, 27 Aug 2021 12:07:06 +0300
From:   Dan Carpenter <dan.carpenter@oracle.com>
To:     Pavel Skripkin <paskripkin@gmail.com>
Cc:     Larry.Finger@lwfinger.net, phil@philpotter.co.uk,
        gregkh@linuxfoundation.org, straube.linux@gmail.com,
        fmdefrancesco@gmail.com, linux-staging@lists.linux.dev,
        linux-kernel@vger.kernel.org
Subject: Re: [PATCH v3 3/6] staging: r8188eu: add error handling of rtw_read8
Message-ID: <20210827090706.GA12231@kadam>
References: <cover.1629789580.git.paskripkin@gmail.com>
 <c59d5d850bf9aab208704182c83086609289cb9c.1629789580.git.paskripkin@gmail.com>
Content-Type: text/plain; charset=us-ascii
Content-Disposition: inline
In-Reply-To: <c59d5d850bf9aab208704182c83086609289cb9c.1629789580.git.paskripkin@gmail.com>
User-Agent: Mutt/1.9.4 (2018-02-28)
MIME-Version: 1.0
X-MS-Exchange-MessageSentRepresentingType: 1
Received: from kadam (62.8.83.99) by JNAP275CA0058.ZAFP275.PROD.OUTLOOK.COM (2603:1086:0:4f::6) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.20.4457.22 via Frontend Transport; Fri, 27 Aug 2021 09:07:19 +0000
X-MS-PublicTrafficType: Email
X-MS-Office365-Filtering-Correlation-Id: 7a7686cb-4487-449d-388a-08d9693a155e
X-MS-TrafficTypeDiagnostic: CO6PR10MB5569:
X-MS-Exchange-Transport-Forked: True
X-Microsoft-Antispam-PRVS: <CO6PR10MB55691F7F0875147B6A91EC438EC89@CO6PR10MB5569.namprd10.prod.outlook.com>
X-MS-Oob-TLC-OOBClassifiers: OLM:4941;
X-MS-Exchange-SenderADCheck: 1
X-MS-Exchange-AntiSpam-Relay: 0
X-Microsoft-Antispam: BCL:0;
X-Microsoft-Antispam-Message-Info: 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
X-Forefront-Antispam-Report: CIP:255.255.255.255;CTRY:;LANG:en;SCL:1;SRV:;IPV:NLI;SFV:NSPM;H:MWHPR1001MB2365.namprd10.prod.outlook.com;PTR:;CAT:NONE;SFS:(346002)(39860400002)(376002)(136003)(366004)(396003)(44832011)(4744005)(86362001)(33716001)(186003)(6916009)(38100700002)(478600001)(5660300002)(83380400001)(38350700002)(1076003)(9686003)(33656002)(66946007)(55016002)(66476007)(956004)(6666004)(8676002)(26005)(8936002)(2906002)(52116002)(316002)(4326008)(66556008)(9576002)(6496006);DIR:OUT;SFP:1101;
X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1
X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?y1yxvHPMvsCGw5QTmO4LZYYdNNNsfx4PP/VX1NJZgKANM9neQEK9qpGcSf8/?=
 =?us-ascii?Q?Qmka8Ca9k11MTNmonxfhcEE300S3Gty8wdW6Hjqtup7G/oBtwxc/muDDd+0d?=
 =?us-ascii?Q?CQbDruMJtu7mKS+1A+P6XFgbYBS0KOp4RvnI9tJsZ1RTDSoMWe+saR59uA1y?=
 =?us-ascii?Q?OQFrRbvgSNdTjaCuYhWrC7UAgansgh6AH2jv3NpHXIEAAr9ORZJ85iG4qcqC?=
 =?us-ascii?Q?wjQ6qTX80knks1v8FbQjW7ubSXrcSfW+kKmwsuAHLVlKT89UcCWwPzz94oMR?=
 =?us-ascii?Q?Cvi9Z8FCNn25QPvJAJpUpU4rVVeTb71LR2Qfet2zupFEqjbuDYWgwftNhIm+?=
 =?us-ascii?Q?bIn5RU2Hzo2pxVn0k85+JVtbXf++kZtHgF+0T8t877p0Qhl8J9qB1KnohQZW?=
 =?us-ascii?Q?xb+497ov/qVOEwITbEYBK4JNsU7HONjbbQQlgkmfyEULp6qrIvbjZ+SAxV6O?=
 =?us-ascii?Q?UCbwVCE6ker0/6YeUDC+ZRp+r3gTuYZSe2tA9PBjX7XjaJYGJbHHJSOdjNy4?=
 =?us-ascii?Q?cP7oVT6041F3+ylafueNZYXy9kzVlxkJhjL5xuYtkyAPfEeHGt+nVYJFRUHI?=
 =?us-ascii?Q?kRrsFHzL47pU6dTt8lQTrkt8Dvnu8jSTlBKPszMWCtXFK5UHSc1opeYGtHV3?=
 =?us-ascii?Q?bHkedcD47At0B7KO5Uc/92CCLN++ufKvavHkcXDo4Q4pBg8fc8qmo8pfiZxf?=
 =?us-ascii?Q?bkEpsan5oTFgqCRIDeKqHqaIQXKbonPnEe5y7mFoNPKMcpc6lPRyz8MBq8k9?=
 =?us-ascii?Q?Akp5iyIbE2IygxIHLsoLRwPc/cRCV7GSWorQwl50gDmgpUNPrMaW6hul9wVM?=
 =?us-ascii?Q?WNeE49+Cp6S9L1KJ4RKocfJqqbsXu45g6ETkT3PtANesX2VkSg56z5fyWzHf?=
 =?us-ascii?Q?YXIzK3Eel6MT8brsfiHEdzwdWqfpmw0zp76UnwZJjptsDGjlWFB4/ri0lbQl?=
 =?us-ascii?Q?AJnGCzfdu8guuAD6N1v75/FE22siZdeagy2kST2OJBpCfbdgCVvNd3kUOPNy?=
 =?us-ascii?Q?Z31E1Srrza/XDKcPeSpvrpcjufn8EnIv4jGu6AP4kNvFsDIb4MklENYwIvSp?=
 =?us-ascii?Q?nVzo5B8sYR0/Ww2SHyOjUPEFEi3NJj13eEPbf5GhUUu9rnPIfrOBZFAStNVU?=
 =?us-ascii?Q?SI6UJ0CLgNS7DOQ1VBL31Jp+ZYyg5MyHpPUl3F0chhT60qCPDIkYKoOlmf64?=
 =?us-ascii?Q?BnUxj4hrOsZjdHf/SapzpVp2DA7JKavL9gU4uxPYYMBYYjcyaWPexp0i/WuZ?=
 =?us-ascii?Q?g7udLSTXjdthLoLY83psNjom14OQwglfqBOI1GIk9O9zhpBgmRKHK2tW7fMO?=
 =?us-ascii?Q?jbpNeUgR715IQeBtBD4y0g1A?=
X-OriginatorOrg: oracle.com
X-MS-Exchange-CrossTenant-Network-Message-Id: 7a7686cb-4487-449d-388a-08d9693a155e
X-MS-Exchange-CrossTenant-AuthSource: MWHPR1001MB2365.namprd10.prod.outlook.com
X-MS-Exchange-CrossTenant-AuthAs: Internal
X-MS-Exchange-CrossTenant-OriginalArrivalTime: 27 Aug 2021 09:07:24.2821
 (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: RVrwv11p5qD9vd605oVekMsxyy7mTJv2W69cqNpFU7nYDpMZcOD1mr5NzO82f1hBNNMX/ravRA0dj3Ttdj6eusBgSG1+IUYabSCwXYkw64g=
X-MS-Exchange-Transport-CrossTenantHeadersStamped: CO6PR10MB5569
X-Proofpoint-Virus-Version: vendor=nai engine=6300 definitions=10088 signatures=668682
X-Proofpoint-Spam-Details: rule=notspam policy=default score=0 suspectscore=0 phishscore=0 spamscore=0
 bulkscore=0 mlxlogscore=999 malwarescore=0 adultscore=0 mlxscore=0
 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2107140000
 definitions=main-2108270058
X-Proofpoint-ORIG-GUID: ui6U8y5XmsbmO8eMx42dl9_T798nSgZa
X-Proofpoint-GUID: ui6U8y5XmsbmO8eMx42dl9_T798nSgZa
Precedence: bulk
List-ID: <linux-kernel.vger.kernel.org>
X-Mailing-List: linux-kernel@vger.kernel.org

On Tue, Aug 24, 2021 at 10:27:27AM +0300, Pavel Skripkin wrote:
> @@ -83,7 +83,12 @@ int proc_get_read_reg(char *page, char **start,
>  
>  	switch (proc_get_read_len) {
>  	case 1:
> -		len += snprintf(page + len, count - len, "rtw_read8(0x%x)=0x%x\n", proc_get_read_addr, rtw_read8(padapter, proc_get_read_addr));
> +		error = rtw_read8(padapter, proc_get_read_addr, (u8 *) &tmp);
> +		if (error)
> +			return len;
> +
> +		len += snprintf(page + len, count - len, "rtw_read8(0x%x)=0x%x\n",
> +				proc_get_read_addr, (u8) tmp);
>  		break;

Oh my goodness...  :P

If you look at what proc_get_read_addr is, it turns out it's a 32bit
address which is controlled by the user in proc_set_read_reg().  LOL!
Just a giant security hole.

My advise is just delete this dead code.  No one is using it so how
necessary can it be?

regards,
dan carpenter