From 7ce198e1235215df15545a704d6bded4ea728da8 Mon Sep 17 00:00:00 2001 From: Lukasz Majewski Date: Tue, 24 Sep 2019 14:22:42 +0200 Subject: y2038: linux: Provide __clock_settime64 implementation This patch provides new __clock_settime64 explicit 64 bit function for setting the time. Moreover, a 32 bit version - __clock_settime - has been refactored to internally use __clock_settime64. The __clock_settime is now supposed to be used on systems still supporting 32 bit time (__TIMESIZE != 64) - hence the necessary conversion to 64 bit struct timespec. The new clock_settime64 syscall available from Linux 5.1+ has been used, when applicable. In this patch the internal padding (tv_pad) of struct __timespec64 is left untouched (on systems with __WORDSIZE == 32) as Linux kernel ignores upper 32 bits of tv_nsec. Build tests: - The code has been tested on x86_64/x86 (native compilation): make PARALLELMFLAGS="-j8" && make xcheck PARALLELMFLAGS="-j8" - The glibc has been build tested (make PARALLELMFLAGS="-j8") for x86 (i386), x86_64-x32, and armv7 Run-time tests: - Run specific tests on ARM/x86 32bit systems (qemu): https://github.com/lmajewski/meta-y2038 and run tests: https://github.com/lmajewski/y2038-tests/commits/master - Use of cross-test-ssh.sh for ARM (armv7): make PARALLELMFLAGS="-j8" test-wrapper='./cross-test-ssh.sh root@192.168.7.2' xcheck Linux kernel, headers and minimal kernel version for glibc build test matrix: - Linux v5.1 (with clock_settime64) and glibc build with v5.1 as minimal kernel version (--enable-kernel="5.1.0") The __ASSUME_TIME64_SYSCALLS flag defined. - Linux v5.1 and default minimal kernel version The __ASSUME_TIME64_SYSCALLS not defined, but kernel supports __clock_settime64 syscalls. - Linux v4.19 (no clock_settime64 support) with default minimal kernel version for contemporary glibc This kernel doesn't support __clock_settime64 syscalls, so the fallback to clock_settime is tested. The above tests were performed with Y2038 redirection applied as well as without (so the __TIMESIZE != 64 execution path is checked as well). No regressions were observed. * include/time.h (__clock_settime64): Add __clock_settime alias according to __TIMESIZE define * sysdeps/unix/sysv/linux/clock_settime.c (__clock_settime): Refactor this function to be used only on 32 bit machines as a wrapper on __clock_settime64. * sysdeps/unix/sysv/linux/clock_settime.c (__clock_settime64): Add * sysdeps/unix/sysv/linux/clock_settime.c (__clock_settime64): Use clock_settime64 kernel syscall (available from 5.1+ Linux) --- sysdeps/unix/sysv/linux/clock_settime.c | 36 +++++++++++++++++++++++++++++---- 1 file changed, 32 insertions(+), 4 deletions(-) (limited to 'sysdeps/unix/sysv/linux') diff --git a/sysdeps/unix/sysv/linux/clock_settime.c b/sysdeps/unix/sysv/linux/clock_settime.c index f76178e0f6..fb48de5d50 100644 --- a/sysdeps/unix/sysv/linux/clock_settime.c +++ b/sysdeps/unix/sysv/linux/clock_settime.c @@ -20,11 +20,9 @@ #include #include -#include "kernel-posix-cpu-timers.h" - /* Set CLOCK to value TP. */ int -__clock_settime (clockid_t clock_id, const struct timespec *tp) +__clock_settime64 (clockid_t clock_id, const struct __timespec64 *tp) { /* Make sure the time cvalue is OK. */ if (tp->tv_nsec < 0 || tp->tv_nsec >= 1000000000) @@ -33,8 +31,38 @@ __clock_settime (clockid_t clock_id, const struct timespec *tp) return -1; } - return INLINE_SYSCALL_CALL (clock_settime, clock_id, tp); +#ifdef __ASSUME_TIME64_SYSCALLS +# ifndef __NR_clock_settime64 +# define __NR_clock_settime64 __NR_clock_settime +# endif + return INLINE_SYSCALL_CALL (clock_settime64, clock_id, tp); +#else +# ifdef __NR_clock_settime64 + int ret = INLINE_SYSCALL_CALL (clock_settime64, clock_id, tp); + if (ret == 0 || errno != ENOSYS) + return ret; +# endif + if (! in_time_t_range (tp->tv_sec)) + { + __set_errno (EOVERFLOW); + return -1; + } + + struct timespec ts32 = valid_timespec64_to_timespec (*tp); + return INLINE_SYSCALL_CALL (clock_settime, clock_id, &ts32); +#endif } + +#if __TIMESIZE != 64 +int +__clock_settime (clockid_t clock_id, const struct timespec *tp) +{ + struct __timespec64 ts64 = valid_timespec_to_timespec64 (*tp); + + return __clock_settime64 (clock_id, &ts64); +} +#endif + libc_hidden_def (__clock_settime) versioned_symbol (libc, __clock_settime, clock_settime, GLIBC_2_17); -- cgit 1.4.1