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From: Rasmus Villemoes <linux@rasmusvillemoes.dk>
To: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: Andrew Morton <akpm@linux-foundation.org>, Tejun Heo <tj@kernel.org>,
        linux-kernel@vger.kernel.org, Kees Cook <keescook@chromium.org>
Subject: Re: [PATCH 1/4] lib/vsprintf.c: handle invalid format specifiers more robustly
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Date: Mon, 28 Sep 2015 22:12:23 +0200
In-Reply-To: <1443427691.8361.226.camel@linux.intel.com> (Andy Shevchenko's
	message of "Mon, 28 Sep 2015 11:08:11 +0300")
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On Mon, Sep 28 2015, Andy Shevchenko <andriy.shevchenko@linux.intel.com> wrote:

>>  		/*
>> -		 * Since %n poses a greater security risk than 
>> utility, treat
>> -		 * it as an invalid format specifier. Warn about its 
>> use so
>> -		 * that new instances don't get added.
>> +		 * Since %n poses a greater security risk than
>
> Any reason to wrap first string?

I just hit M-q in emacs and let that take care of somewhat sane
wrapping. I don't play diff golf.

>> +			/*
>> +			 * Presumably the arguments passed gcc's 
>> type
>> +			 * checking, but there is no safe or sane 
>> way
>> +			 * for us to continue parsing the format and
>> +			 * fetching from the va_list; the remaining
>> +			 * specifiers and arguments would be out of
>> +			 * sync.
>
> Could we use wider strings in the commentary here?

Ditto.

Rasmus