[PATCH v2] selftests/lsm: Fix memory leak in attr_lsm_count

[William Roberts]

On Fri, Jul 3, 2026 at 7:10 AM Wang Yan <wangyan01 at kylinos.cn> wrote:
>
> The calloc-allocated buffer in attr_lsm_count() is never released on
> any exit path, including both the normal return path and the early
> return when read_sysfs_lsms fails, resulting in a heap memory leak.
>
> Add free() for the buffer on all return branches to fix the leak.
>
> Fixes: d3d929a8b0cd ("LSM: selftests for Linux Security Module syscalls")
> Signed-off-by: Wang Yan <wangyan01 at kylinos.cn>
> ---
>  tools/testing/selftests/lsm/common.c | 4 +++-
>  1 file changed, 3 insertions(+), 1 deletion(-)
>
> diff --git a/tools/testing/selftests/lsm/common.c b/tools/testing/selftests/lsm/common.c
> index 9ad258912646..927dce4f04cb 100644
> --- a/tools/testing/selftests/lsm/common.c
> +++ b/tools/testing/selftests/lsm/common.c
> @@ -76,7 +76,7 @@ int attr_lsm_count(void)
>                 return 0;
>
>         if (read_sysfs_lsms(names, sysconf(_SC_PAGESIZE)))
> -               return 0;
> +               goto out;
>
>         if (strstr(names, "selinux"))
>                 count++;
> @@ -85,5 +85,7 @@ int attr_lsm_count(void)
>         if (strstr(names, "apparmor"))
>                 count++;
>
> +out:
> +       free(names);
>         return count;
>  }
> --
> 2.25.1
>

Reviewed-by: William Roberts <bill.c.roberts at gmail.com>
Tested-by: William Roberts <bill.c.roberts at gmail.com>