Re: [PATCH 1/2] y2038: make CONFIG_64BIT_TIME unconditional

From: Thomas Gleixner
Date: Mon Apr 29 2019 - 03:34:08 EST

On Fri, 26 Apr 2019, Arnd Bergmann wrote:

> As Stepan Golosunov points out, we made a small mistake in the
> get_timespec64() function in the kernel. It was originally added under
> the assumption that CONFIG_64BIT_TIME would get enabled on all 32-bit
> and 64-bit architectures, but when I did the conversion, I only turned
> it on for 32-bit ones.
> The effect is that the get_timespec64() function never clears the upper
> half of the tv_nsec field for 32-bit tasks in compat mode. Clearing this
> is required for POSIX compliant behavior of functions that pass a
> 'timespec' structure with a 64-bit tv_sec and a 32-bit tv_nsec, plus
> uninitialized padding.
> The easiest fix for linux-5.1 is to just make the Kconfig symbol
> unconditional, as it was originally intended. As a follow-up,
> we should remove any #ifdef CONFIG_64BIT_TIME completely.
> Link:
> Cc: Lukasz Majewski <lukma@xxxxxxx>
> Cc: Stepan Golosunov <stepan@xxxxxxxxxxxxxxx>
> Signed-off-by: Arnd Bergmann <arnd@xxxxxxxx>
> ---
> Please apply this one as a bugfix for 5.1

Can you provide a 'Fixes: ....' tag please?