Re: [PATCH 1/1] tty: fix up atime/mtime mess, take four

From: Jiri Slaby
Date: Mon Mar 09 2015 - 06:01:23 EST


On 03/06/2015, 02:16 PM, Raymond Jennings wrote:
> On Fri, 2015-02-27 at 18:40 +0100, Jiri Slaby wrote:
>> So check the absolute difference of times and if it large than "8
>> seconds or so", always update the time. That means we will update
>> immediatelly when changing time. Ergo, CAP_SYS_TIME can foul the
>> check, but it was always that way.
>
> If I may ask, what is supposed to happen normally when you write to a
> tty device? I always thought the tty device was treated just like a
> normal file wrt. timestamps.
>
> Now I see a patch for 8 seconds something.

Yes, because you do not want to be given any clue when users are typing
passwords. You could intercept the length of the password from the
pauses between key strokes (tty timestamps).

thanks,
--
js
suse labs
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