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Date: Fri, 3 Nov 2017 01:04:09 +0900
From: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
To: "Tobin C. Harding" <me@tobin.cc>
Cc: Sergey Senozhatsky <sergey.senozhatsky.work@gmail.com>,
        Sergey Senozhatsky <sergey.senozhatsky@gmail.com>,
        kernel-hardening@lists.openwall.com,
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        Djalal Harouni <tixxdz@gmail.com>, linux-kernel@vger.kernel.org
Subject: Re: [PATCH V8 0/2] printk: hash addresses printed with %p
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On (11/02/17 21:14), Tobin C. Harding wrote:
[..]
> I can put my email address if there is not a better option.

sounds good.


> > hm... just a huge pile of if's
> > 
> > 	if (is_vmalloc_addr(addr))
> > 		do_hashing(addr);
> > 	else if (__module_address(addr))
> > 		do_hashing(addr);
> > 	else if (is_kernel(addr) || is_kernel_inittext(addr))
> > 	...
> > 
> > but that's going to be really messy and "iffy".
> 
> This is the only suggestion we have so far.
> 

well... one more: check if we can safely dereference it. if so
it's a pointer, probably :)

	if (!probe_kernel_address(addr, p))
		do_hashing(addr);


just an idea.

	-ss