On Thu, Apr 21, 2022 at 6:01 AM Gaosheng Cui <[email protected]> wrote:
>
> The make_parent_dir is called without null-pointer checking for path,
> such as bpf_link__pin. To ensure there is no null-pointer dereference
> in make_parent_dir, so make_parent_dir requires additional null-pointer
> checking for path.
>
> Signed-off-by: Gaosheng Cui <[email protected]>
> ---
> tools/lib/bpf/libbpf.c | 3 +++
> 1 file changed, 3 insertions(+)
>
> diff --git a/tools/lib/bpf/libbpf.c b/tools/lib/bpf/libbpf.c
> index b53e51884f9e..5786e6184bf5 100644
> --- a/tools/lib/bpf/libbpf.c
> +++ b/tools/lib/bpf/libbpf.c
> @@ -7634,6 +7634,9 @@ static int make_parent_dir(const char *path)
> char *dname, *dir;
> int err = 0;
>
> + if (path == NULL)
> + return -EINVAL;
> +
API contract is that path shouldn't be NULL. Just like we don't check
link, obj, prog for NULL in every single API, I don't think we need to
do it here, unless I'm missing something?
> dname = strdup(path);
> if (dname == NULL)
> return -ENOMEM;
> --
> 2.25.1
>