linux-kernel - Re: [PATCH v3 2/3] vfio/pci: Tolerate oversized BARs by disallowing mmap

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

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Date: Wed, 19 Jun 2024 21:09:56 -0700
From: Christoph Hellwig <hch@...radead.org>
To: Niklas Schnelle <schnelle@...ux.ibm.com>
Cc: Christoph Hellwig <hch@...radead.org>,
	Alex Williamson <alex.williamson@...hat.com>,
	Gerald Schaefer <gerald.schaefer@...ux.ibm.com>,
	Heiko Carstens <hca@...ux.ibm.com>,
	Vasily Gorbik <gor@...ux.ibm.com>,
	Alexander Gordeev <agordeev@...ux.ibm.com>,
	Christian Borntraeger <borntraeger@...ux.ibm.com>,
	Sven Schnelle <svens@...ux.ibm.com>,
	Gerd Bayer <gbayer@...ux.ibm.com>,
	Matthew Rosato <mjrosato@...ux.ibm.com>,
	Jason Gunthorpe <jgg@...pe.ca>, linux-s390@...r.kernel.org,
	linux-kernel@...r.kernel.org, kvm@...r.kernel.org
Subject: Re: [PATCH v3 2/3] vfio/pci: Tolerate oversized BARs by disallowing
 mmap

On Wed, Jun 19, 2024 at 12:56:47PM +0200, Niklas Schnelle wrote:
> In short, the ISM BAR 0 is stupidly large but this is intentional. It
> not fitting in the VMAP is simply the least crazy filter I could come
> up with to keep the ISM device from causing trouble for use of vfio-pci
> mmap() for other, normal, PCI devices.

Then maybe add a PCI quirk to prevent mapping it.  This would also
affect the sysfs resource0 file unless I'm missing something.