This prepares sys_futex for y2038 safe calling: the native syscall is changed to receive a __kernel_timespec argument, which will be switched to 64-bit time_t in the future. All the internal time handling gets changed to timespec64, and the compat_sys_futex entry point is moved under the CONFIG_COMPAT_32BIT_TIME check to provide compatibility for existing 32-bit architectures.
Signed-off-by: Arnd Bergmann arnd@arndb.de --- include/linux/syscalls.h | 2 +- kernel/futex.c | 22 ++++++++++++---------- 2 files changed, 13 insertions(+), 11 deletions(-)
diff --git a/include/linux/syscalls.h b/include/linux/syscalls.h index a27cf407de92..247ad9eca955 100644 --- a/include/linux/syscalls.h +++ b/include/linux/syscalls.h @@ -553,7 +553,7 @@ asmlinkage long sys_unshare(unsigned long unshare_flags);
/* kernel/futex.c */ asmlinkage long sys_futex(u32 __user *uaddr, int op, u32 val, - struct timespec __user *utime, u32 __user *uaddr2, + struct __kernel_timespec __user *utime, u32 __user *uaddr2, u32 val3); asmlinkage long sys_get_robust_list(int pid, struct robust_list_head __user * __user *head_ptr, diff --git a/kernel/futex.c b/kernel/futex.c index 5cc7c3b098e9..b305beaab739 100644 --- a/kernel/futex.c +++ b/kernel/futex.c @@ -3558,10 +3558,10 @@ long do_futex(u32 __user *uaddr, int op, u32 val, ktime_t *timeout,
SYSCALL_DEFINE6(futex, u32 __user *, uaddr, int, op, u32, val, - struct timespec __user *, utime, u32 __user *, uaddr2, + struct __kernel_timespec __user *, utime, u32 __user *, uaddr2, u32, val3) { - struct timespec ts; + struct timespec64 ts; ktime_t t, *tp = NULL; u32 val2 = 0; int cmd = op & FUTEX_CMD_MASK; @@ -3571,12 +3571,12 @@ SYSCALL_DEFINE6(futex, u32 __user *, uaddr, int, op, u32, val, cmd == FUTEX_WAIT_REQUEUE_PI)) { if (unlikely(should_fail_futex(!(op & FUTEX_PRIVATE_FLAG)))) return -EFAULT; - if (copy_from_user(&ts, utime, sizeof(ts)) != 0) + if (get_timespec64(&ts, utime)) return -EFAULT; - if (!timespec_valid(&ts)) + if (!timespec64_valid(&ts)) return -EINVAL;
- t = timespec_to_ktime(ts); + t = timespec64_to_ktime(ts); if (cmd == FUTEX_WAIT) t = ktime_add_safe(ktime_get(), t); tp = &t; @@ -3747,12 +3747,14 @@ COMPAT_SYSCALL_DEFINE3(get_robust_list, int, pid,
return ret; } +#endif /* CONFIG_COMPAT */
+#ifdef CONFIG_COMPAT_32BIT_TIME COMPAT_SYSCALL_DEFINE6(futex, u32 __user *, uaddr, int, op, u32, val, struct old_timespec32 __user *, utime, u32 __user *, uaddr2, u32, val3) { - struct timespec ts; + struct timespec64 ts; ktime_t t, *tp = NULL; int val2 = 0; int cmd = op & FUTEX_CMD_MASK; @@ -3760,12 +3762,12 @@ COMPAT_SYSCALL_DEFINE6(futex, u32 __user *, uaddr, int, op, u32, val, if (utime && (cmd == FUTEX_WAIT || cmd == FUTEX_LOCK_PI || cmd == FUTEX_WAIT_BITSET || cmd == FUTEX_WAIT_REQUEUE_PI)) { - if (compat_get_timespec(&ts, utime)) + if (get_old_timespec32(&ts, utime)) return -EFAULT; - if (!timespec_valid(&ts)) + if (!timespec64_valid(&ts)) return -EINVAL;
- t = timespec_to_ktime(ts); + t = timespec64_to_ktime(ts); if (cmd == FUTEX_WAIT) t = ktime_add_safe(ktime_get(), t); tp = &t; @@ -3776,7 +3778,7 @@ COMPAT_SYSCALL_DEFINE6(futex, u32 __user *, uaddr, int, op, u32, val,
return do_futex(uaddr, op, val, tp, uaddr2, val2, val3); } -#endif /* CONFIG_COMPAT */ +#endif /* CONFIG_COMPAT_32BIT_TIME */
static void __init futex_detect_cmpxchg(void) {