[PATCH 4/4] clock_settime/clock_gettime: Use __nonnull to avoid null pointer

[Siddhesh Poyarekar]

On 28/04/2022 17:55, Xiaoming Ni via Libc-alpha wrote:
> clock_settime()
> clock_settime64()
> clock_gettime()
> clock_gettime64()
> Add __nonnull((2)) to avoid null pointer access.
> 
> Link: https://sourceware.org/bugzilla/show_bug.cgi?id=27662
> Link: https://sourceware.org/bugzilla/show_bug.cgi?id=29084
> Signed-off-by: Xiaoming Ni <nixiaoming@huawei.com>
> ---
>   include/time.h | 4 ++--
>   time/time.h    | 9 ++++++---
>   2 files changed, 8 insertions(+), 5 deletions(-)
> 
> diff --git a/include/time.h b/include/time.h
> index 127347eb90..a64eff54f5 100644
> --- a/include/time.h
> +++ b/include/time.h
> @@ -166,7 +166,7 @@ libc_hidden_proto (__timegm64)
>   # define __clock_settime64 __clock_settime
>   #else
>   extern int __clock_settime64 (clockid_t clock_id,
> -                              const struct __timespec64 *tp);
> +                              const struct __timespec64 *tp) __nonnull((2));
>   libc_hidden_proto (__clock_settime64)
>   #endif
>   
> @@ -324,7 +324,7 @@ extern int __clock_nanosleep_time64 (clockid_t clock_id,
>                                        int flags, const struct __timespec64 *req,
>                                        struct __timespec64 *rem);
>   libc_hidden_proto (__clock_nanosleep_time64)
> -extern int __clock_gettime64 (clockid_t clock_id, struct __timespec64 *tp);
> +extern int __clock_gettime64 (clockid_t clock_id, struct __timespec64 *tp) __nonnull((2));
>   libc_hidden_proto (__clock_gettime64)
>   extern int __timespec_get64 (struct __timespec64 *ts, int base);
>   libc_hidden_proto (__timespec_get64)
> diff --git a/time/time.h b/time/time.h
> index 847ac3f8c0..26f276f147 100644
> --- a/time/time.h
> +++ b/time/time.h
> @@ -276,11 +276,12 @@ extern int nanosleep (const struct timespec *__requested_time,
>   extern int clock_getres (clockid_t __clock_id, struct timespec *__res) __THROW;
>   
>   /* Get current value of clock CLOCK_ID and store it in TP.  */
> -extern int clock_gettime (clockid_t __clock_id, struct timespec *__tp) __THROW;
> +extern int clock_gettime (clockid_t __clock_id, struct timespec *__tp)
> +     __THROW __nonnull((2));
>   
>   /* Set clock CLOCK_ID to value TP.  */
>   extern int clock_settime (clockid_t __clock_id, const struct timespec *__tp)
> -     __THROW;
> +     __THROW __nonnull((2));
>   # else
>   #  ifdef __REDIRECT
>   extern int __REDIRECT (nanosleep, (const struct timespec *__requested_time,
> @@ -291,8 +292,10 @@ extern int __REDIRECT_NTH (clock_getres, (clockid_t __clock_id,
>                              __clock_getres64);
>   extern int __REDIRECT_NTH (clock_gettime, (clockid_t __clock_id, struct
>                                              timespec *__tp), __clock_gettime64);

The semicolon at the end needs to go away.  This was also caught by 
patchwork trybot:

https://patchwork.sourceware.org/project/glibc/patch/20220428122529.108208-5-nixiaoming@huawei.com/
https://www.delorie.com/trybots/32bit/8846/make.tail.txt

> +                           __nonnull((2));
>   extern int __REDIRECT_NTH (clock_settime, (clockid_t __clock_id, const struct
> -                                           timespec *__tp), __clock_settime64);
> +                                           timespec *__tp), __clock_settime64)
> +                           __nonnull((2));
>   #  else
>   #   define nanosleep __nanosleep64
>   #   define clock_getres __clock_getres64