RE: [char-misc-next 3/3] mei: report consistently copy_from/to_user failures

From: Winkler, Tomas
Date: Tue Mar 11 2014 - 18:39:19 EST




> On Tue, 11 Mar 2014 14:49:25 +0200
> Tomas Winkler <tomas.winkler@xxxxxxxxx> wrote:
>
> > From: Alexander Usyskin <alexander.usyskin@xxxxxxxxx>
> >
> > Consistently display error on possible copy_from/to_user failures
> > and replace dev_dbg with dev_err
>
> NAK
>
> This allows users to flood the logs by deliberately causing lots of these
> failed to copy data error messages, and if they can flood the logs they
> can hide other stuff.
>
> The -EFAULT cases should be consistent - but consistently *not* logged.

Yep, that's really looks like a possible exploit, please drop this patch.
Tomas
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/