From ddccf40fe82b7ac7c44b186ec4b6d1d1bbc2cbff Mon Sep 17 00:00:00 2001 From: Arnd Bergmann Date: Thu, 23 Nov 2017 14:29:37 +0100 Subject: y2038: vdso: change timeval to __kernel_old_timeval The gettimeofday() function in vdso uses the traditional 'timeval' structure layout, which will be incompatible with future versions of glibc on 32-bit architectures that use a 64-bit time_t. This interface is problematic for y2038, when time_t overflows on 32-bit architectures, but the plan so far is that a libc with 64-bit time_t will not call into the gettimeofday() vdso helper at all, and only have a method for entering clock_gettime(). This means we don't have to fix it here, though we probably want to add a new clock_gettime() entry point using a 64-bit version of 'struct timespec' at some point. Changing the vdso code to use __kernel_old_timeval helps isolate this usage from the other ones that still need to be fixed properly, and it gets us closer to removing the 'timeval' definition from the kernel sources. Reviewed-by: Thomas Gleixner Signed-off-by: Arnd Bergmann --- arch/x86/entry/vsyscall/vsyscall_64.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'arch/x86/entry') diff --git a/arch/x86/entry/vsyscall/vsyscall_64.c b/arch/x86/entry/vsyscall/vsyscall_64.c index e7c596dea947..76e62bcb8d87 100644 --- a/arch/x86/entry/vsyscall/vsyscall_64.c +++ b/arch/x86/entry/vsyscall/vsyscall_64.c @@ -184,7 +184,7 @@ bool emulate_vsyscall(unsigned long error_code, */ switch (vsyscall_nr) { case 0: - if (!write_ok_or_segv(regs->di, sizeof(struct timeval)) || + if (!write_ok_or_segv(regs->di, sizeof(struct __kernel_old_timeval)) || !write_ok_or_segv(regs->si, sizeof(struct timezone))) { ret = -EFAULT; goto check_fault; -- cgit v1.2.3 From 21346564ccad17b928cf0d51584608531d91d298 Mon Sep 17 00:00:00 2001 From: Arnd Bergmann Date: Tue, 5 Nov 2019 11:10:01 +0100 Subject: y2038: vdso: change time_t to __kernel_old_time_t Only x86 uses the 'time' syscall in vdso, so change that to __kernel_old_time_t as a preparation for removing 'time_t' and '__kernel_time_t' later. Reviewed-by: Thomas Gleixner Signed-off-by: Arnd Bergmann --- arch/x86/entry/vdso/vclock_gettime.c | 6 +++--- arch/x86/entry/vsyscall/vsyscall_64.c | 2 +- arch/x86/um/vdso/um_vdso.c | 4 ++-- lib/vdso/gettimeofday.c | 4 ++-- 4 files changed, 8 insertions(+), 8 deletions(-) (limited to 'arch/x86/entry') diff --git a/arch/x86/entry/vdso/vclock_gettime.c b/arch/x86/entry/vdso/vclock_gettime.c index d9ff616bb0f6..7d70935b6758 100644 --- a/arch/x86/entry/vdso/vclock_gettime.c +++ b/arch/x86/entry/vdso/vclock_gettime.c @@ -15,7 +15,7 @@ #include "../../../../lib/vdso/gettimeofday.c" extern int __vdso_gettimeofday(struct __kernel_old_timeval *tv, struct timezone *tz); -extern time_t __vdso_time(time_t *t); +extern __kernel_old_time_t __vdso_time(__kernel_old_time_t *t); int __vdso_gettimeofday(struct __kernel_old_timeval *tv, struct timezone *tz) { @@ -25,12 +25,12 @@ int __vdso_gettimeofday(struct __kernel_old_timeval *tv, struct timezone *tz) int gettimeofday(struct __kernel_old_timeval *, struct timezone *) __attribute__((weak, alias("__vdso_gettimeofday"))); -time_t __vdso_time(time_t *t) +__kernel_old_time_t __vdso_time(__kernel_old_time_t *t) { return __cvdso_time(t); } -time_t time(time_t *t) __attribute__((weak, alias("__vdso_time"))); +__kernel_old_time_t time(__kernel_old_time_t *t) __attribute__((weak, alias("__vdso_time"))); #if defined(CONFIG_X86_64) && !defined(BUILD_VDSO32_64) diff --git a/arch/x86/entry/vsyscall/vsyscall_64.c b/arch/x86/entry/vsyscall/vsyscall_64.c index 76e62bcb8d87..bba5bfdb2a56 100644 --- a/arch/x86/entry/vsyscall/vsyscall_64.c +++ b/arch/x86/entry/vsyscall/vsyscall_64.c @@ -194,7 +194,7 @@ bool emulate_vsyscall(unsigned long error_code, break; case 1: - if (!write_ok_or_segv(regs->di, sizeof(time_t))) { + if (!write_ok_or_segv(regs->di, sizeof(__kernel_old_time_t))) { ret = -EFAULT; goto check_fault; } diff --git a/arch/x86/um/vdso/um_vdso.c b/arch/x86/um/vdso/um_vdso.c index 371724cf70da..2112b8d14668 100644 --- a/arch/x86/um/vdso/um_vdso.c +++ b/arch/x86/um/vdso/um_vdso.c @@ -37,7 +37,7 @@ int __vdso_gettimeofday(struct __kernel_old_timeval *tv, struct timezone *tz) int gettimeofday(struct __kernel_old_timeval *, struct timezone *) __attribute__((weak, alias("__vdso_gettimeofday"))); -time_t __vdso_time(time_t *t) +__kernel_old_time_t __vdso_time(__kernel_old_time_t *t) { long secs; @@ -47,7 +47,7 @@ time_t __vdso_time(time_t *t) return secs; } -time_t time(time_t *t) __attribute__((weak, alias("__vdso_time"))); +__kernel_old_time_t time(__kernel_old_time_t *t) __attribute__((weak, alias("__vdso_time"))); long __vdso_getcpu(unsigned *cpu, unsigned *node, struct getcpu_cache *unused) diff --git a/lib/vdso/gettimeofday.c b/lib/vdso/gettimeofday.c index 45f57fd2db64..9ecfd3b547ba 100644 --- a/lib/vdso/gettimeofday.c +++ b/lib/vdso/gettimeofday.c @@ -164,10 +164,10 @@ __cvdso_gettimeofday(struct __kernel_old_timeval *tv, struct timezone *tz) } #ifdef VDSO_HAS_TIME -static __maybe_unused time_t __cvdso_time(time_t *time) +static __maybe_unused __kernel_old_time_t __cvdso_time(__kernel_old_time_t *time) { const struct vdso_data *vd = __arch_get_vdso_data(); - time_t t = READ_ONCE(vd[CS_HRES_COARSE].basetime[CLOCK_REALTIME].sec); + __kernel_old_time_t t = READ_ONCE(vd[CS_HRES_COARSE].basetime[CLOCK_REALTIME].sec); if (time) *time = t; -- cgit v1.2.3