[LTP] [PATCH] semctl09: Fix heap smash

[Yang Xu <xuyang2018.jy@cn.fujitsu.com>]

Hi Martin
LGTM, pushed. Thanks.

Best Regards
Yang Xu

> semctl() expects pointer to a buffer as its fourth argument, not pointer
> to a pointer. Passing&un.buf results in heap smash that corrupts internal
> LTP data structures on some archs.
>
> CC: Feiyu Zhu<zhufy.jy@cn.fujitsu.com>
> Signed-off-by: Martin Doucha<mdoucha@suse.cz>
> ---
>   testcases/kernel/syscalls/ipc/semctl/semctl09.c | 8 ++++++--
>   1 file changed, 6 insertions(+), 2 deletions(-)
>
> diff --git a/testcases/kernel/syscalls/ipc/semctl/semctl09.c b/testcases/kernel/syscalls/ipc/semctl/semctl09.c
> index 131bfbc07..d36ba62e5 100644
> --- a/testcases/kernel/syscalls/ipc/semctl/semctl09.c
> +++ b/testcases/kernel/syscalls/ipc/semctl/semctl09.c
> @@ -51,11 +51,15 @@ static union semun un;
>    */
>   static inline int do_semctl(int semid, int semnum, int cmd)
>   {
> +	struct semid_ds info;
> +
> +	un.buf =&info;
> +
>   	switch (tst_variant) {
>   	case 0:
> -		return tst_syscall(__NR_semctl, semid, semnum, cmd,&un.buf);
> +		return tst_syscall(__NR_semctl, semid, semnum, cmd, un);
>   	case 1:
> -		return semctl(semid, semnum, cmd,&un.buf);
> +		return semctl(semid, semnum, cmd, un);
>   	}
>   	return -1;
>   }