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Date: Sun, 2 Dec 2012 18:10:57 +0000
From: Alan Cox <alan@lxorguk.ukuu.org.uk>
To: Paul Fulghum <paulkf@microgate.com>
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Subject: Re: [PATCH] synclink fix ldisc buffer argument
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On Sun, 2 Dec 2012 10:11:58 -0600
Paul Fulghum <paulkf@microgate.com> wrote:

> True, in this mode line disciplines other than N_HDLC would not be functional and N_HDLC ignores the flag buffer.
> This change won’t make other line disciplines useful, it will just prevent the case of a mistakenly selected line discipline accessing beyond the end of the (dummy) flag buffer.
> 
> I’m fine with or without the change. It is functional now with a chance to read past then end of a buffer if misconfigured. With the change, it has the same functionality without the ability to read past the end of a buffer if misconfigured.

With the change its feeding crap in the flags buffer, which may matter in
future depending what happens to the other bits.

If this is a real issue far better to just kzalloc a blank flag buffer to
match the mtu.