Re: [PATCH v4] n_tty: Fix buffer overruns with larger-than-4k pastes

[Greg Kroah-Hartman]

On Tue, Dec 10, 2013 at 05:12:02PM -0500, Peter Hurley wrote:
> readline() inadvertently triggers an error recovery path when
> pastes larger than 4k overrun the line discipline buffer. The
> error recovery path discards input when the line discipline buffer
> is full and operating in canonical mode and no newline has been
> received. Because readline() changes the termios to non-canonical
> mode to read the line char-by-char, the line discipline buffer
> can become full, and then when readline() restores termios back
> to canonical mode for the caller, the now-full line discipline
> buffer triggers the error recovery.
> 
> When changing termios from non-canon to canon mode and the read
> buffer contains data, simulate an EOF push _without_ the
> DISABLED_CHAR in the read buffer.
> 
> Importantly for the readline() problem, the termios can be
> changed back to non-canonical mode without changes to the read
> buffer occurring; ie., as if the previous termios change had not
> happened (as long as no intervening read took place).
> 
> Preserve existing userspace behavior which allows '\0's already
> received in non-canon mode to be read as '\0's in canon mode
> (rather than trigger add'l EOF pushes or an actual EOF).
> 
> Patch based on original proposal and discussion here
> https://bugzilla.kernel.org/show_bug.cgi?id=55991
> by Stas Sergeev <stsp@xxxxxxxxxxxxxxxxxxxxx>
> 
> Reported-by: Margarita Manterola <margamanterola@xxxxxxxxx>
> Cc: Maximiliano Curia <maxy@xxxxxxxxxxxxxxxxx>
> Cc: Pavel Machek <pavel@xxxxxx>
> Cc: Arkadiusz Miskiewicz <a.miskiewicz@xxxxxxxxx>
> Acked-by: Stas Sergeev <stsp@xxxxxxxxxxxxxxxxxxxxx>
> Signed-off-by: Peter Hurley <peter@xxxxxxxxxxxxxxxxxx>
> ---

Is this a 3.13-final thing, or can it wait for 3.14-rc1?

thanks,

greg k-h
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