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
| ||
|
Message-ID: <20180419093306.rn5bz264nxsn7d7c@node.shutemov.name> Date: Thu, 19 Apr 2018 12:33:06 +0300 From: "Kirill A. Shutemov" <kirill@...temov.name> To: Andrey Konovalov <andreyknvl@...gle.com> Cc: Catalin Marinas <catalin.marinas@....com>, Will Deacon <will.deacon@....com>, Jonathan Corbet <corbet@....net>, Mark Rutland <mark.rutland@....com>, Robin Murphy <robin.murphy@....com>, Al Viro <viro@...iv.linux.org.uk>, James Morse <james.morse@....com>, Kees Cook <keescook@...omium.org>, Bart Van Assche <bart.vanassche@....com>, Kate Stewart <kstewart@...uxfoundation.org>, Greg Kroah-Hartman <gregkh@...uxfoundation.org>, Thomas Gleixner <tglx@...utronix.de>, Philippe Ombredanne <pombredanne@...b.com>, Andrew Morton <akpm@...ux-foundation.org>, Ingo Molnar <mingo@...nel.org>, "Kirill A . Shutemov" <kirill.shutemov@...ux.intel.com>, Dan Williams <dan.j.williams@...el.com>, "Aneesh Kumar K . V" <aneesh.kumar@...ux.vnet.ibm.com>, Zi Yan <zi.yan@...rutgers.edu>, linux-arm-kernel@...ts.infradead.org, linux-doc@...r.kernel.org, linux-kernel@...r.kernel.org, linux-mm@...ck.org, Dmitry Vyukov <dvyukov@...gle.com>, Kostya Serebryany <kcc@...gle.com>, Evgeniy Stepanov <eugenis@...gle.com>, Lee Smith <Lee.Smith@....com>, Ramana Radhakrishnan <Ramana.Radhakrishnan@....com>, Jacob Bramley <Jacob.Bramley@....com>, Ruben Ayrapetyan <Ruben.Ayrapetyan@....com> Subject: Re: [PATCH 0/6] arm64: untag user pointers passed to the kernel On Wed, Apr 18, 2018 at 08:53:09PM +0200, Andrey Konovalov wrote: > Hi! > > arm64 has a feature called Top Byte Ignore, which allows to embed pointer > tags into the top byte of each pointer. Userspace programs (such as > HWASan, a memory debugging tool [1]) might use this feature and pass > tagged user pointers to the kernel through syscalls or other interfaces. > > This patch makes a few of the kernel interfaces accept tagged user > pointers. The kernel is already able to handle user faults with tagged > pointers and has the untagged_addr macro, which this patchset reuses. > > We're not trying to cover all possible ways the kernel accepts user > pointers in one patchset, so this one should be considered as a start. How many changes do you anticipate? This patchset looks small and reasonable, but I see a potential to become a boilerplate. Would we need to change every driver which implements ioctl() to strip these bits? -- Kirill A. Shutemov
Powered by blists - more mailing lists