Re: [PATCH] kernel: escape non-ASCII and control characters inprintk()

From: Vasiliy Kulikov
Date: Wed Jun 22 2011 - 15:07:51 EST

Hi Alan,

On Wed, Jun 22, 2011 at 19:10 +0100, Alan Cox wrote:
> If that is set you shouldn't be filtering out unicode, just control codes.


> Minor other nit is that you might want to allow BEL through and you
> certainly want to allow tab through.

In what situation do you think BEL makes sense in kernel log? I cannot
image the situation. Alarms should use KERN_EMERG/KERN_ALERT log level.

> The core code should not be hardcoding policy assumptions about symbol
> sets and ASCII, for an awful lot of consoles today that assumption is
> just plain wrong, for others it makes sense

No problem, I don't insist.

> So with tty maintainer hat on - NAK to the current approach but a good
> idea to do it properly.

The final check should be:

if (iscntrl(c) && (c != '\n') && (c != '\t'))

Any comments against this variant?


Vasiliy Kulikov - bringing security into open computing environments
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