[LTP] [PATCH] syscalls/shmctl05.c: Fix leak of shared memory segment

[xuyang2018.jy@fujitsu.com]

Hi Ian

Thanks! Applied.

Best Regards
Yang Xu
> The cleanup function is using the key 0xF00F instead of the id in the shmctl call.
> This causes the shared mem segment to not be removed properly.
>
> This can be reproduced with the following:
>
> $ ./shmctl05
> tst_test.c:1342: TINFO: Timeout per run is
> ../../../../../include/tst_fuzzy_sync.h:522: TINFO: Minimum sampling period ended
> ../../../../../include/tst_fuzzy_sync.h:345: TINFO: loop = 1024, delay_bias = 0
> ../../../../../include/tst_fuzzy_sync.h:333: TINFO: start_a - start_b: { avg =   ns, avg_dev =     ns, dev_ratio = }
> ../../../../../include/tst_fuzzy_sync.h:333: TINFO: end_a - start_a  : { avg =   ns, avg_dev =     ns, dev_ratio = }
> ../../../../../include/tst_fuzzy_sync.h:333: TINFO: end_b - start_b  : { avg =   ns, avg_dev =     ns, dev_ratio = }
> ../../../../../include/tst_fuzzy_sync.h:333: TINFO: end_a - end_b    : { avg =   ns, avg_dev =     ns, dev_ratio = }
> ../../../../../include/tst_fuzzy_sync.h:333: TINFO: spins            : { avg =     , avg_dev =       , dev_ratio = }
> ../../../../../include/tst_fuzzy_sync.h:678: TINFO: Exceeded execution time, requesting exit
> shmctl05.c:89: TPASS: didn't crash
>
> Summary:
> passed   1
> failed   0
> broken   0
> skipped  0
> warnings 0
>
> $ ipcs -m
>
> ------ Shared Memory Segments --------
> key        shmid      owner      perms      bytes      nattch     status
> 0x0000f00f 629964859  user       700        4096       0
>
> Fix
> In the cleanup, add a SAFE_SHMGET to fetch the id and pass into shmctl call.
> Confirmed this resolves the leaked segment.
>
> Signed-off-by: Ian May<ian.s.may@gmail.com>
> ---
>   testcases/kernel/syscalls/ipc/shmctl/shmctl05.c | 4 +++-
>   1 file changed, 3 insertions(+), 1 deletion(-)
>
> diff --git a/testcases/kernel/syscalls/ipc/shmctl/shmctl05.c b/testcases/kernel/syscalls/ipc/shmctl/shmctl05.c
> index f8b76bda7..ea7eef6f1 100644
> --- a/testcases/kernel/syscalls/ipc/shmctl/shmctl05.c
> +++ b/testcases/kernel/syscalls/ipc/shmctl/shmctl05.c
> @@ -91,8 +91,10 @@ static void do_test(void)
>
>   static void cleanup(void)
>   {
> +	int id;
>   	tst_fzsync_pair_cleanup(&fzsync_pair);
> -	shmctl(0xF00F, IPC_RMID, NULL);
> +	id = SAFE_SHMGET(0xF00F, 4096, 0);
> +	SAFE_SHMCTL(id, IPC_RMID, NULL);
>   }
>
>   static struct tst_test test = {