Re: [PATCH] serial: off by one

[David Miller]

From: Roel Kluin <roel.kluin@xxxxxxxxx>
Date: Thu, 04 Jun 2009 01:20:33 +0200

> In zs_console_putchar() occurs:
> 
> 	if (zs_transmit_drain(zport, irq))
> 		write_zsdata(zport, ch);
> 
> However if in zs_transmit_drain() no empty Tx Buffer occurs, limit reaches
> -1 => true, and the write still occurs.
> 
> This patch changes postfix to prefix decrements in this and similar
> functions to prevent similar mistakes in the future. This decreases the
> iterations with one but the chosen loop count was arbitrary anyway.
> 
> In sunhv limit reaches -1, not 0, so the test is off by one.
> 
> Signed-off-by: Roel Kluin <roel.kluin@xxxxxxxxx>

Acked-by: David S. Miller <davem@xxxxxxxxxxxxx>
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