Re: CVE-2015-1805 and 3.14-longterm?

[Greg KH <greg@kroah.com>]

On Thu, Jul 02, 2015 at 10:19:34AM +0200, Dick Snippe wrote:
> Hello,
> 
> I'm sorry to bother you with this, but lwn.net reported a rather serious
> security issue a couple of weeks ago:
> 
> http://lwn.net/Articles/646590/
> https://bugzilla.redhat.com/show_bug.cgi?id=1202855
> CVE-2015-1805
> "It was found that the Linux kernel's implementation of vectored pipe
> read and write functionality did not take into account the I/O vectors
> that were already processed when retrying after a failed atomic access
> operation, potentially resulting in memory corruption due to an I/O
> vector array overrun. A local, unprivileged user could use this flaw to
> crash the system or, potentially, escalate their privileges on the
> system."
> 
> It appears that these upstream fixes haven't made it to 3.14.4[456]:
> 
> http://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/commit/?id=f0d1bec9d58d4c038d0ac958c9af82be6eb18045
> http://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/commit/?id=637b58c2887e5e57850865839cc75f59184b23d1
> 
> I'm just a (very happy!) user of the -longterm kernels, so I don't
> know how this normally works. But it would appear that this bug still
> exists in the -longterm kernels.

I think, and I might be wrong here, but because
637b58c2887e5e57850865839cc75f59184b23d1 (switch pipe_read() to
copy_page_to_iter()) is not in the 3.14-stable tree (it showed up in
3.15), that f0d1bec9d58d4c038d0ac958c9af82be6eb18045 (new helper:
copy_page_from_iter()) isn't needed (it showed up in 3.16).

So is this a problem in the 3.14-stable tree?

thanks,

greg k-h