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Message-ID: <1521119343.10722.665.camel@linux.intel.com>
Subject: Re: [PATCH v3] vsprintf: Prevent crash when dereferencing invalid
 pointers
From:   Andy Shevchenko <andriy.shevchenko@linux.intel.com>
To:     Petr Mladek <pmladek@suse.com>,
        Linus Torvalds <torvalds@linux-foundation.org>
Cc:     Rasmus Villemoes <linux@rasmusvillemoes.dk>,
        "Tobin C . Harding" <me@tobin.cc>, Joe Perches <joe@perches.com>,
        Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
        Andrew Morton <akpm@linux-foundation.org>,
        Michal Hocko <mhocko@suse.cz>,
        Sergey Senozhatsky <sergey.senozhatsky@gmail.com>,
        Steven Rostedt <rostedt@goodmis.org>,
        Sergey Senozhatsky <sergey.senozhatsky.work@gmail.com>
Date:   Thu, 15 Mar 2018 15:09:03 +0200
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On Wed, 2018-03-14 at 15:09 +0100, Petr Mladek wrote:
> We already prevent crash when dereferencing some obviously broken
> pointers. But the handling is not consistent. Sometimes we print
> "(null)"
> only for pure NULL pointer, sometimes for pointers in the first
> page and 


> sometimes also for pointers in the last page (error codes).

I still think that printing a hex value of the error code is much better
than some odd "(efault)".


-- 
Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Intel Finland Oy