From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from aserp2130.oracle.com ([141.146.126.79]:52452 "EHLO aserp2130.oracle.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725747AbfDLGai (ORCPT ); Fri, 12 Apr 2019 02:30:38 -0400 Date: Thu, 11 Apr 2019 23:30:23 -0700 From: "Darrick J. Wong" Subject: Re: [PATCH] xfs: use struct_size() helper Message-ID: <20190412063023.GI1019523@magnolia> References: <20190411233758.GA19031@embeddedor> <20190412001941.GV15524@magnolia> <51407603-d144-ece9-6cd5-edea72374527@embeddedor.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <51407603-d144-ece9-6cd5-edea72374527@embeddedor.com> Sender: linux-xfs-owner@vger.kernel.org List-ID: List-Id: xfs To: "Gustavo A. R. Silva" Cc: linux-xfs@vger.kernel.org, linux-kernel@vger.kernel.org On Thu, Apr 11, 2019 at 08:57:14PM -0500, Gustavo A. R. Silva wrote: > > > On 4/11/19 7:19 PM, Darrick J. Wong wrote: > > [fixing linux-xfs cc] > > > > Thanks for this. > > > On Thu, Apr 11, 2019 at 06:37:58PM -0500, Gustavo A. R. Silva wrote: > >> Make use of the struct_size() helper instead of an open-coded version > >> in order to avoid any potential type mistakes, in particular in the > >> context in which this code is being used. > >> > >> So, replace code of the following form: > >> > >> sizeof(*alist) + context->count * sizeof(alist->al_offset[0] > >> > >> with: > >> > >> struct_size(alist, al_offset, context->count) > >> > >> and remove unnecessary variable arraytop. > >> > >> This code was detected with the help of Coccinelle. > >> > >> Signed-off-by: Gustavo A. R. Silva > > > > Has this been run through xfstests? > > > > No. Is this a requirement? Yes, since this is a change to core functionality (and my eyes aren't so good at digging through preprocessor macros...) --D > Thanks > -- > Gustavo > > > --D > > > >> fs/xfs/xfs_attr_list.c | 5 +---- > >> 1 file changed, 1 insertion(+), 4 deletions(-) > >> > >> diff --git a/fs/xfs/xfs_attr_list.c b/fs/xfs/xfs_attr_list.c > >> index 3d213a7394c5..05e03348553e 100644 > >> --- a/fs/xfs/xfs_attr_list.c > >> +++ b/fs/xfs/xfs_attr_list.c > >> @@ -553,7 +553,6 @@ xfs_attr_put_listent( > >> { > >> struct attrlist *alist = (struct attrlist *)context->alist; > >> attrlist_ent_t *aep; > >> - int arraytop; > >> > >> ASSERT(!context->seen_enough); > >> ASSERT(!(context->flags & ATTR_KERNOVAL)); > >> @@ -572,10 +571,8 @@ xfs_attr_put_listent( > >> ((flags & XFS_ATTR_ROOT) == 0)) > >> return; > >> > >> - arraytop = sizeof(*alist) + > >> - context->count * sizeof(alist->al_offset[0]); > >> context->firstu -= ATTR_ENTSIZE(namelen); > >> - if (context->firstu < arraytop) { > >> + if (context->firstu < struct_size(alist, al_offset, context->count)) { > >> trace_xfs_attr_list_full(context); > >> alist->al_more = 1; > >> context->seen_enough = 1; > >> -- > >> 2.21.0 > >>