lists.openwall.net | lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC | |
Open Source and information security mailing list archives
| ||
|
Date: Wed, 4 Mar 2020 18:10:17 +0000 From: Wei Liu <wei.liu@...nel.org> To: Lorenzo Pieralisi <lorenzo.pieralisi@....com> Cc: Wei Liu <wei.liu@...nel.org>, Dexuan Cui <decui@...rosoft.com>, "Gustavo A. R. Silva" <gustavo@...eddedor.com>, KY Srinivasan <kys@...rosoft.com>, Haiyang Zhang <haiyangz@...rosoft.com>, Stephen Hemminger <sthemmin@...rosoft.com>, Sasha Levin <sashal@...nel.org>, Andrew Murray <amurray@...goodpenguin.co.uk>, Bjorn Helgaas <bhelgaas@...gle.com>, "linux-hyperv@...r.kernel.org" <linux-hyperv@...r.kernel.org>, "linux-pci@...r.kernel.org" <linux-pci@...r.kernel.org>, "linux-kernel@...r.kernel.org" <linux-kernel@...r.kernel.org> Subject: Re: [PATCH] PCI: hv: Replace zero-length array with flexible-array member On Wed, Mar 04, 2020 at 06:06:35PM +0000, Lorenzo Pieralisi wrote: > On Wed, Mar 04, 2020 at 05:55:09PM +0000, Wei Liu wrote: > > On Thu, Feb 13, 2020 at 03:43:40AM +0000, Dexuan Cui wrote: > > > > From: linux-hyperv-owner@...r.kernel.org > > > > <linux-hyperv-owner@...r.kernel.org> On Behalf Of Gustavo A. R. Silva > > > > Sent: Wednesday, February 12, 2020 4:51 PM > > > > ... > > > > The current codebase makes use of the zero-length array language > > > > extension to the C90 standard, but the preferred mechanism to declare > > > > variable-length types such as these ones is a flexible array member[1][2], > > > > introduced in C99: > > > > > > > > struct foo { > > > > int stuff; > > > > struct boo array[]; > > > > }; > > > > > > > > By making use of the mechanism above, we will get a compiler warning > > > > in case the flexible array does not occur last in the structure, which > > > > will help us prevent some kind of undefined behavior bugs from being > > > > inadvertently introduced[3] to the codebase from now on. > > > > > > > > Also, notice that, dynamic memory allocations won't be affected by > > > > this change: > > > > > > > > "Flexible array members have incomplete type, and so the sizeof operator > > > > may not be applied. As a quirk of the original implementation of > > > > zero-length arrays, sizeof evaluates to zero."[1] > > > > > > > > This issue was found with the help of Coccinelle. > > > > > > Looks good to me. Thanks, Gustavo! > > > > > > Reviewed-by: Dexuan Cui <decui@...rosoft.com> > > > > > > > Lorenzo, will you be picking up this patch? It seems to me you've been > > handling patches to pci-hyperv.c. This patch is not yet in pci/hv branch > > in your repository. > > > > Let me know what you think. > > I shall pick it up, I checked patchwork and it was erroneously > assigned to Bjorn, that's why I have not taken it yet. > > Fixed now, apologies, I will merge it shortly. Thanks for picking it up. Wei. > > Lorenzo
Powered by blists - more mailing lists