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

From: William Roberts

Date: Fri Jul 03 2026 - 13:57:22 EST


On Fri, Jul 3, 2026 at 7:10 AM Wang Yan <wangyan01@xxxxxxxxxx> 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@xxxxxxxxxx>
> ---
> 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@xxxxxxxxx>
Tested-by: William Roberts <bill.c.roberts@xxxxxxxxx>