From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S933308AbdC3Kws (ORCPT ); Thu, 30 Mar 2017 06:52:48 -0400 Received: from mailout1.samsung.com ([203.254.224.24]:23117 "EHLO epoutp01.samsung.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S932558AbdC3Kwq (ORCPT ); Thu, 30 Mar 2017 06:52:46 -0400 X-AuditID: b6c32a2c-f79be6d0000051f7-64-58dce37be511 MIME-version: 1.0 Content-transfer-encoding: 8BIT Content-type: text/plain; charset="utf-8" Message-id: <58DCE37B.4090308@samsung.com> Date: Thu, 30 Mar 2017 19:52:43 +0900 From: Chanwoo Choi Organization: Samsung Electronics User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:31.0) Gecko/20100101 Thunderbird/31.6.0 To: Andy Shevchenko Cc: "linux-kernel@vger.kernel.org" , Hans de Goede , chanwoo@kernel.org, MyungJoo Ham Subject: Re: [PATCH 1/2] extcon: Use BIT() macro for the left-shift operation In-reply-to: X-Brightmail-Tracker: H4sIAAAAAAAAA+NgFmphk+LIzCtJLcpLzFFi42LZdlhTS7f68Z0Ig9e3NSxeTjjMaDHxxhUW izfHpzNZXN41h83iduMKNgdWj52z7rJ7bFrVyebxft9VNo++LasYPT5vkgtgjUq1yUhNTEkt UkjNS85PycxLt1XyDo53jjc1MzDUNbS0MFdSyEvMTbVVcvEJ0HXLzAFarqRQlphTChQKSCwu VtK3synKLy1JVcjILy6xVYo2NDTSMzQw1zMyMtIzMY61MjIFKklIzTh8bSNzQQd3xZop/A2M nRxdjJwcEgImEudfrmSBsMUkLtxbz9bFyMUhJLCUUWJPw2dWCKedSeLPsmlsMB3vezYygdhC AssZJbb1ZYDYvAKCEj8m3wOaxMHBLCAvceRSNkiYWUBT4sWXSSwQ5fcYJc6frIQo15JoePCC FcRmEVCVmPb5N9h4NqD4/hc3wGx+AUWJqz8eM4LYogIREjvnf2PvYmTnEBHQl9hfBnIZM8gB fYcPgJUIC/hL3NlyBuwyToFgiQdrLzCCFEkIrGKXaNjQyQhymoSArMSmA8wQpovEqVniEE8J S7w6voUdwpaW+Lv0FlRrO6PE5jkgX4E4HYwS91c2skJUGUvcf3CPGeJHPone30+YIIbySnS0 CUGYHhKbbrpBVDtKbLt/mx0SmieYJDZsucUygVFhFlLAzUIE3CykgFvAyLyKUSy1oDg3PbXY tMBQrzgxt7g0L10vOT93EyM4BWrp7GC8t8D7EKMAB6MSD6+Gx50IIdbEsuLK3EOMEhzMSiK8 YQ+AQrwpiZVVqUX58UWlOanFhxhNgQE/kVlKNDkfmJ7zSuINTSwNTEzNjA2MDS0slcR5NVZe ixASSE8sSc1OTS1ILYLpY+LglGpglFfYtLlrY5y3g/Vhx5hTT4U/nFVbajJVJmRSJs+0CRce 3vvnLfiqhy/hYj3nvfTJAcHVjzYvE9QMui/2TbghgP/wocV6TNO6lLdrv9y2fWn7lKe3Tmtr ZYou9Jxn/ULe+NzHk183rA46IbYg29Bn1vUXfmVvvUwlXq4yPe60I+FY3xWGHbHZXEosxRmJ hlrMRcWJAN1SU3mXAwAA X-Brightmail-Tracker: H4sIAAAAAAAAA+NgFtrAIsWRmVeSWpSXmKPExsVy+t9jAd3qx3ciDLrfSlu8nHCY0WLijSss Fm+OT2eyuLxrDpvF7cYVbA6sHjtn3WX32LSqk83j/b6rbB59W1YxenzeJBfAGuVmk5GamJJa pJCal5yfkpmXbqsUGuKma6GkkJeYm2qrFKHrGxKkpFCWmFMK5BkZoAEH5wD3YCV9uwS3jMPX NjIXdHBXrJnC38DYydHFyMkhIWAi8b5nIxOELSZx4d56ti5GLg4hgaWMEqdurGQHSfAKCEr8 mHyPpYuRg4NZQF7iyKVsCFNdYsqUXIjyB4wSK+/sZoMo15JoePCCFcRmEVCVmPb5N1icDSi+ /8UNMJtfQFHi6o/HjCBzRAUiJLpPVHYxsnOICOhL7C8DmcgssJxR4su/08wg1cICvhJnJywC u1JI4BSTxMtvciA2p0CwxPZNv9knMArOQnLnLIQ7ZyHcuYCReRWjRGpBckFxUnquUV5quV5x Ym5xaV66XnJ+7iZGcGw9k97BeHiX+yFGAQ5GJR7eirW3I4RYE8uKK3MPMUpwMCuJ8IY9uBMh xJuSWFmVWpQfX1Sak1p8iNEU6NGJzFKiyfnAuM8riTc0MTcxNzawMLe0NDFSEudtnP0sXEgg PbEkNTs1tSC1CKaPiYNTqoFR/saqKafapgvsjfkrzDxbvoCj9t7pvIYPGf5hZ6x4qoKEeyJu LDg1UyWWJbGnbkb4xWUezXPTv7A/CGp+fPHE9E2rnb0O7Dy2YR9fwvzLv2ue8zD+vqDqPf/t 7XVvAvvuPpwVbTBpndrfb6VK7zQ4l/x2WCaUfp3xc4X2/inX/5bN+H363KNSDSWW4oxEQy3m ouJEAFsgUvfDAgAA X-MTR: 20000000000000000@CPGS X-CMS-MailID: 20170330105243epcas5p32785704be5c11282c30dc29244c54e1c X-Msg-Generator: CA X-Sender-IP: 203.254.230.27 X-Local-Sender: =?UTF-8?B?7LWc7LCs7JqwG1RpemVuIFBsYXRmb3JtIExhYihTL1fshLw=?= =?UTF-8?B?7YSwKRvsgrzshLHsoITsnpAbU2VuaW9yIEVuZ2luZWVy?= X-Global-Sender: =?UTF-8?B?Q2hhbndvbyBDaG9pG1RpemVuIFBsYXRmb3JtIExhYi4bU2Ft?= =?UTF-8?B?c3VuZyBFbGVjdHJvbmljcxtTZW5pb3IgRW5naW5lZXI=?= X-Sender-Code: =?UTF-8?B?QzEwG1NUQUYbQzEwVjgxMTE=?= CMS-TYPE: 105P DLP-Filter: Pass X-CFilter-Loop: Reflected X-CMS-RootMailID: 20170330083943epcas1p4ccc3a12576a7232162a682b73eaeea0b X-RootMTR: 20170330083943epcas1p4ccc3a12576a7232162a682b73eaeea0b References: <1490863178-12782-1-git-send-email-cw00.choi@samsung.com> <58DCCCB6.2030206@samsung.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 2017년 03월 30일 19:38, Andy Shevchenko wrote: > On Thu, Mar 30, 2017 at 12:15 PM, Chanwoo Choi wrote: >> On 2017년 03월 30일 17:59, Andy Shevchenko wrote: >>> On Thu, Mar 30, 2017 at 11:39 AM, Chanwoo Choi wrote: >>>> This patch just uses the BIT() macro to make the code simple. >>> >>>> for (i = 0; i < edev->max_supported; i++) { >>>> count += sprintf(buf + count, "%s=%d\n", >>>> extcon_info[edev->supported_cable[i]].name, >>>> - !!(edev->state & (1 << i))); >>>> + !!(edev->state & BIT(i))); >>>> } >>> >>> While change is okay, the above code is fragile. There is a potential >>> buffer overflow. >> >> When extcon device is registered, extcon_dev_register() check a number of >> supported external connectors. The maximum number of supported connectors >> is 32. There is no buffer overflow. > > Is there any limit for name? No, there is not (const char *name). > Though for now it is quite unlikely to have the issue. If there is problem, I want to fix it. I hope your more comment because I don't understand what you point out. Did you mention the length of connector name? or buf? > > Feel free to proceed despite my comment. > -- Best Regards, Chanwoo Choi Samsung Electronics