Re: [kernel-hardening] Re: [PATCH v9 1/4] syscalls: Verify address limit before returning to user-mode

From: Christoph Hellwig
Date: Tue May 09 2017 - 12:04:52 EST


On Tue, May 09, 2017 at 06:02:50AM -0700, Christoph Hellwig wrote:
> On Tue, May 09, 2017 at 06:00:01AM -0700, Andy Lutomirski wrote:
> > fs/splice.c has some, ahem, interesting uses that have been the source
> > of nasty exploits in the past. Converting them to use iov_iter
> > properly would be really, really nice. Christoph, I don't suppose
> > you'd like to do that?
>
> I can take care of all the fs code including this one.

I spent the afternoon hacking up where I'd like this to head. It's
completely untested as of now:

http://git.infradead.org/users/hch/vfs.git/shortlog/refs/heads/setfs-elimination