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  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, 18 Sep 2017 11:31:37 +0200
From:   Jan Kara <>
To:     Christoph Hellwig <>
Cc:     Dan Williams <>, Jan Kara <>,
        "Darrick J. Wong" <>,
        Arnd Bergmann <>,
        "" <>,
        Linux API <>,
        Linux Kernel Mailing List <>,, linux-mm <>,
        Andy Lutomirski <>,
        linux-fsdevel <>,
        Andrew Morton <>
Subject: Re: [PATCH v4 2/3] mm: introduce MAP_VALIDATE a mechanism for adding
 new mmap flags

On Sun 17-09-17 19:39:45, Christoph Hellwig wrote:
> On Sat, Sep 16, 2017 at 08:44:14PM -0700, Dan Williams wrote:
> > So it wasn't all that easy, and Linus declined to take it. I think we
> > should add a new ->mmap_validate() file operation and save the
> > tree-wide cleanup until later.
> Note that we already have a mmap_capabilities callout for nommu,
> I wonder if we could generalize that.

So if I understood Dan right, Linus refused to merge the patch which adds
'flags' argument to ->mmap callback. That is actually logically independent
change from validating flags passed to mmap(2) syscall. Dan did it just to
save himself from adding a VMA flag for MAP_DIRECT.

For validating flags passed to mmap(2), I agree we could use
->mmap_capabilities() instead of mmap_supported_mask Dan has added. But I
don't have a strong opinion there.

Jan Kara <>

Powered by blists - more mailing lists