linux-kernel - Re: [PATCH v6 03/11] mm, x86: Add support for eXclusive Page Frame Ownership (XPFO)

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:   Mon, 13 Nov 2017 14:20:17 -0800
From:   Dave Hansen <dave.hansen@...el.com>
To:     Tycho Andersen <tycho@...ker.com>
Cc:     linux-kernel@...r.kernel.org, linux-mm@...ck.org,
        kernel-hardening@...ts.openwall.com,
        Marco Benatto <marco.antonio.780@...il.com>,
        Juerg Haefliger <juerg.haefliger@...onical.com>, x86@...nel.org
Subject: Re: [PATCH v6 03/11] mm, x86: Add support for eXclusive Page Frame
 Ownership (XPFO)

On 11/09/2017 05:09 PM, Tycho Andersen wrote:
> which I guess is from the additional flags in grow_dev_page() somewhere down
> the stack. Anyway... it seems this is a kernel allocation that's using
> MIGRATE_MOVABLE, so perhaps we need some more fine tuned heuristic than just
> all MOVABLE allocations are un-mapped via xpfo, and all the others are mapped.
> 
> Do you have any ideas?

It still has to do a kmap() or kmap_atomic() to be able to access it.  I
thought you hooked into that.  Why isn't that path getting hit for these?