Peter Hurley 5859b90777 serial: omap: Prevent DoS using unprivileged ioctl(TIOCSRS485) ...

commit 308bbc9ab8 upstream.

The omap-serial driver emulates RS485 delays using software timers,
but neglects to clamp the input values from the unprivileged
ioctl(TIOCSRS485). Because the software implementation busy-waits,
malicious userspace could stall the cpu for ~49 days.

Clamp the input values to < 100ms.

Fixes: 4a0ac0f55b ("OMAP: add RS485 support")
Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

2016-02-25 12:01:14 -08:00

48 KiB

Raw Blame History

View Raw