Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753491Ab3I2Gwp (ORCPT ); Sun, 29 Sep 2013 02:52:45 -0400 Received: from userp1040.oracle.com ([156.151.31.81]:32592 "EHLO userp1040.oracle.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751311Ab3I2Gwn (ORCPT ); Sun, 29 Sep 2013 02:52:43 -0400 Message-ID: <5247CECC.9050003@oracle.com> Date: Sun, 29 Sep 2013 14:55:08 +0800 From: vaughan User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:17.0) Gecko/20130805 Thunderbird/17.0.8 MIME-Version: 1.0 To: Jeff Moyer CC: axboe@kernel.dk, linux-kernel@vger.kernel.org, alexey.kodanev@oracle.com Subject: Re: [PATCH v2] block: register_blkdev doesn't check name against NULL References: <1378809614-17490-1-git-send-email-vaughan.cao@oracle.com> <1378866250-22679-1-git-send-email-vaughan.cao@oracle.com> In-Reply-To: Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit X-Source-IP: acsinet22.oracle.com [141.146.126.238] Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1326 Lines: 29 On 09/23/2013 10:56 PM, Jeff Moyer wrote: > Vaughan Cao writes: > >> register_blkdev(0, NULL) can result kernel Oops by copying from NULL >> in strlcpy(). Fix it by checking NULL pointer at the beginning and >> WARN when encountered in unregister_blkdev. > Uhh, so yeah, this is an exported function, so I could see maybe wanting > to do the argument checking. But honestly, if your driver can't even > get this right, is there any hope of it actually working? > > This seems like a pointless patch to me, but ultimately it's up to Jens. > > Cheers, > Jeff > > p.s. the kerneldoc tells you what to put there: > * @name: the name of the new block device as a zero terminated string Thanks for your comment, Jeff. I have the same feeling as you, however, shouldn't kernel do its best to provide the maximum stable working ability? And it's test case 7 of block driver in ltp project - http://sourceforge.net/p/ltp/git/ci/master/tree/testcases/kernel/device-drivers/block/kernel_space/test_block.c. It seems their attitude is we should check this. Vaughan -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/