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Date: Tue, 3 Apr 2018 22:57:23 +0900
From: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
To: Petr Mladek <pmladek@suse.com>
Cc: Sergey Senozhatsky <sergey.senozhatsky.work@gmail.com>,
        Andy Shevchenko <andriy.shevchenko@linux.intel.com>,
        Linus Torvalds <torvalds@linux-foundation.org>,
        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>
Subject: Re: [PATCH v3] vsprintf: Prevent crash when dereferencing invalid
 pointers
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On (04/03/18 13:52), Petr Mladek wrote:
> On Tue 2018-04-03 10:12:37, Sergey Senozhatsky wrote:
> > On (04/02/18 17:15), Andy Shevchenko wrote:
> > > > 
> > > > Hmm, I have never seen the error code in this form.
> > > 
> > > We have limited space to print it and error numbers currently can be up
> > > to 0xfff (4095). So, I have no better idea how to squeeze them while
> > > thinking that "(efault)" is much harder to parse in case of error
> > 
> > 'efault' looks to me like a misspelled 'default', for some reason.
> 
> I wonder if (-efault) would help a bit.

Dunno. If the pointer is invalid and -EFAULTS then I guess we are not
leaking anything critical and may be can just print it out. May be I'm
wrong.

	-ss