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=-13.8 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS 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 8F3AAC48BC2 for ; Sun, 27 Jun 2021 22:42:22 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 6835161A1D for ; Sun, 27 Jun 2021 22:42:22 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231738AbhF0Woq (ORCPT ); Sun, 27 Jun 2021 18:44:46 -0400 Received: from mail108.syd.optusnet.com.au ([211.29.132.59]:45699 "EHLO mail108.syd.optusnet.com.au" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231644AbhF0Wop (ORCPT ); Sun, 27 Jun 2021 18:44:45 -0400 Received: from dread.disaster.area (pa49-179-138-183.pa.nsw.optusnet.com.au [49.179.138.183]) by mail108.syd.optusnet.com.au (Postfix) with ESMTPS id A5D9F1B093D; Mon, 28 Jun 2021 08:42:18 +1000 (AEST) Received: from dave by dread.disaster.area with local (Exim 4.92.3) (envelope-from ) id 1lxdTl-0009vs-If; Mon, 28 Jun 2021 08:42:17 +1000 Date: Mon, 28 Jun 2021 08:42:17 +1000 From: Dave Chinner To: Wang Shilong Cc: linux-ext4@vger.kernel.org, Wang Shilong Subject: Re: [PATCH] ext4: forbid U32_MAX project ID Message-ID: <20210627224217.GL2419729@dread.disaster.area> References: <20210625124033.5639-1-wangshilong1991@gmail.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20210625124033.5639-1-wangshilong1991@gmail.com> X-Optus-CM-Score: 0 X-Optus-CM-Analysis: v=2.3 cv=F8MpiZpN c=1 sm=1 tr=0 a=MnllW2CieawZLw/OcHE/Ng==:117 a=MnllW2CieawZLw/OcHE/Ng==:17 a=kj9zAlcOel0A:10 a=r6YtysWOX24A:10 a=lB0dNpNiAAAA:8 a=7-415B0cAAAA:8 a=olheZxfBlaoEw9cQjO0A:9 a=CjuIK1q_8ugA:10 a=c-ZiYqmG3AbHTdtsH08C:22 a=biEYGPWJfzWAr4FL6Ov7:22 Precedence: bulk List-ID: X-Mailing-List: linux-ext4@vger.kernel.org On Fri, Jun 25, 2021 at 08:40:33AM -0400, Wang Shilong wrote: > From: Wang Shilong > > U32_MAX is reserved for special purpose, > qid_has_mapping() will return false if projid is > 4294967295, dqget() will return NULL for it. > > So U32_MAX is unsupported Project ID, fix to forbid > it. Actually, it's INVALID_PROJID, not U32_MAX, and we already have a check function for that: static inline bool projid_valid(kprojid_t projid) { return !projid_eq(projid, INVALID_PROJID); } > Signed-off-by: Wang Shilong > --- > fs/ext4/ioctl.c | 3 +++ > 1 file changed, 3 insertions(+) > > diff --git a/fs/ext4/ioctl.c b/fs/ext4/ioctl.c > index 31627f7dc5cd..f3a8d962c291 100644 > --- a/fs/ext4/ioctl.c > +++ b/fs/ext4/ioctl.c > @@ -744,6 +744,9 @@ int ext4_fileattr_set(struct user_namespace *mnt_userns, > u32 flags = fa->flags; > int err = -EOPNOTSUPP; > > + if (fa->fsx_projid >= U32_MAX) > + return -EINVAL; > + This should actually be calling qid_valid() or projid_valid(), and it should be in generic code because multiple filesystems support project quotas. i.e this should be checked in fileattr_set_prepare(), not in ext4 specific code. Cheers, Dave. -- Dave Chinner david@fromorbit.com