| Message ID | 20190429131951.471701-1-arnd@arndb.de |
|---|---|
| State | Accepted |
| Commit | f3d964673b2f1c5d5c68c77273efcf7103eed03b |
| Headers | show |
| Series | [1/2] y2038: make CONFIG_64BIT_TIME unconditional | expand |
diff --git a/arch/Kconfig b/arch/Kconfig index 33687dddd86a..9092e0ffe4d3 100644 --- a/arch/Kconfig +++ b/arch/Kconfig @@ -764,7 +764,7 @@ config COMPAT_OLD_SIGACTION bool config 64BIT_TIME - def_bool ARCH_HAS_64BIT_TIME + def_bool y help This should be selected by all architectures that need to support new system calls with a 64-bit time_t. This is relevant on all 32-bit
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. Note: for native 32-bit mode, no change is needed, this works as designed and user space should never need to clear the upper 32 bits of the tv_nsec field, in or out of the kernel. Fixes: 00bf25d693e7 ("y2038: use time32 syscall names on 32-bit") Link: https://lore.kernel.org/lkml/20190422090710.bmxdhhankurhafxq@sghpc.golosunov.pp.ru/ Cc: Lukasz Majewski <lukma@denx.de> Cc: Stepan Golosunov <stepan@golosunov.pp.ru> Signed-off-by: Arnd Bergmann <arnd@arndb.de> --- Please apply this one as a bugfix for 5.1 --- arch/Kconfig | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) -- 2.20.0