From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-8.4 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,UNPARSEABLE_RELAY, USER_AGENT_SANE_1 autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 9749CC4332E for ; Mon, 23 Mar 2020 11:43:04 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 6DE9D206F9 for ; Mon, 23 Mar 2020 11:43:04 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=oracle.com header.i=@oracle.com header.b="uE8Qkvw2" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728186AbgCWLm6 (ORCPT ); Mon, 23 Mar 2020 07:42:58 -0400 Received: from userp2130.oracle.com ([156.151.31.86]:33722 "EHLO userp2130.oracle.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728152AbgCWLm5 (ORCPT ); Mon, 23 Mar 2020 07:42:57 -0400 Received: from pps.filterd (userp2130.oracle.com [127.0.0.1]) by userp2130.oracle.com (8.16.0.42/8.16.0.42) with SMTP id 02NBdECu114405; Mon, 23 Mar 2020 11:42:38 GMT DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=oracle.com; h=date : from : to : cc : subject : message-id : references : mime-version : content-type : in-reply-to; s=corp-2020-01-29; bh=M30jtPOLXFGKh0OiBXL0iPiQWOfFHuziHXXkfFK5U2A=; b=uE8Qkvw2f3iHluL4afcTXM89lN+Rk8kalQNFUp6khL4h8gwllbrTeC571hY/4dbu1g3U ENC9sI6rW4qhccdHsYwSYmrHyzCRq2zKBt8LK760Lxgzf/BfzozNLTCio1sbx0Q1gKzC kLnf6bcxj+7cc5bRK8Od8AK2oIpPcHmkSVxoDrfdX94z/FJXGVJRF0fJzCtVHq+AZOvy 4Qr5g3phfgZa+TZpTuTqQP7fxUNc/guPC/z+g0WEeJfC65kSmX99YPbgW3yQvXxFoS58 bUouP3AGJ/BEez8IFVRqoNihkPPE/7TvQ3AMpc6nZEhRN4/z92pEJtsElpqUXgAfOHlf ag== Received: from aserp3020.oracle.com (aserp3020.oracle.com [141.146.126.70]) by userp2130.oracle.com with ESMTP id 2ywabqx2yj-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Mon, 23 Mar 2020 11:42:38 +0000 Received: from pps.filterd (aserp3020.oracle.com [127.0.0.1]) by aserp3020.oracle.com (8.16.0.42/8.16.0.42) with SMTP id 02NBfv2U064536; Mon, 23 Mar 2020 11:42:38 GMT Received: from userv0121.oracle.com (userv0121.oracle.com [156.151.31.72]) by aserp3020.oracle.com with ESMTP id 2ywvqqywbk-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Mon, 23 Mar 2020 11:42:37 +0000 Received: from abhmp0014.oracle.com (abhmp0014.oracle.com [141.146.116.20]) by userv0121.oracle.com (8.14.4/8.13.8) with ESMTP id 02NBgX4V004477; Mon, 23 Mar 2020 11:42:34 GMT Received: from kadam (/41.57.98.10) by default (Oracle Beehive Gateway v4.0) with ESMTP ; Mon, 23 Mar 2020 04:42:33 -0700 Date: Mon, 23 Mar 2020 14:42:25 +0300 From: Dan Carpenter To: Qiujun Huang Cc: syzbot , aeb@cwi.nl, danarag@gmail.com, kstewart@linuxfoundation.org, linux-kernel@vger.kernel.org, syzkaller-bugs@googlegroups.com, tglx@linutronix.de, viro@zeniv.linux.org.uk Subject: Re: KASAN: null-ptr-deref Write in get_block Message-ID: <20200323114225.GE26299@kadam> References: <000000000000cbeaf705a15a9b30@google.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.9.4 (2018-02-28) X-Proofpoint-Virus-Version: vendor=nai engine=6000 definitions=9568 signatures=668685 X-Proofpoint-Spam-Details: rule=notspam policy=default score=0 spamscore=0 phishscore=0 bulkscore=0 suspectscore=2 mlxlogscore=999 malwarescore=0 mlxscore=0 adultscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2003020000 definitions=main-2003230069 X-Proofpoint-Virus-Version: vendor=nai engine=6000 definitions=9568 signatures=668685 X-Proofpoint-Spam-Details: rule=notspam policy=default score=0 spamscore=0 suspectscore=2 lowpriorityscore=0 malwarescore=0 phishscore=0 priorityscore=1501 clxscore=1011 adultscore=0 mlxscore=0 mlxlogscore=999 bulkscore=0 impostorscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2003020000 definitions=main-2003230068 Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Fix the subject to [PATCH] minix: Fix NULL dereference in alloc_branch() On Sun, Mar 22, 2020 at 08:06:48PM +0800, Qiujun Huang wrote: > Need to check the return value of sb_getblk. > Add a Reported-by tag. Reported-by: syzbot+4a88b2b9dc280f47baf4@syzkaller.appspotmail.com > Signed-off-by: Qiujun Huang > --- > fs/minix/itree_common.c | 2 ++ > 1 file changed, 2 insertions(+) > > diff --git a/fs/minix/itree_common.c b/fs/minix/itree_common.c > index 043c3fd..eedd79f 100644 > --- a/fs/minix/itree_common.c > +++ b/fs/minix/itree_common.c > @@ -85,6 +85,8 @@ static int alloc_branch(struct inode *inode, > break; > branch[n].key = cpu_to_block(nr); > bh = sb_getblk(inode->i_sb, parent); > + if (!bh) > + break; The patch is white space damaged and we need to do a bit of error handling before the break as well. bh = sb_getblk(inode->i_sb, parent); + if (!bh) { + minix_free_block(inode, block_to_cpu(branch[n].key)); + break; + } lock_buffer(bh); Please fix those few things and resend. regards, dan carpenter