lists.openwall.net   lists  /  announce  owl-users  owl-dev  john-users  john-dev  passwdqc-users  yescrypt  popa3d-users  /  oss-security  kernel-hardening  musl  sabotage  tlsify  passwords  /  crypt-dev  xvendor  /  Bugtraq  Full-Disclosure  linux-kernel  linux-netdev  linux-ext4  linux-hardening  PHC 
Open Source and information security mailing list archives
 
Hash Suite: Windows password security audit tool. GUI, reports in PDF.
[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]
Date:   Wed, 2 Sep 2020 19:15:05 -0700
From:   Andrii Nakryiko <andrii.nakryiko@...il.com>
To:     Stanislav Fomichev <sdf@...gle.com>
Cc:     Networking <netdev@...r.kernel.org>, bpf <bpf@...r.kernel.org>,
        "David S. Miller" <davem@...emloft.net>,
        Alexei Starovoitov <ast@...nel.org>,
        Daniel Borkmann <daniel@...earbox.net>,
        YiFei Zhu <zhuyifei@...gle.com>,
        YiFei Zhu <zhuyifei1999@...il.com>
Subject: Re: [PATCH bpf-next v3 2/8] bpf: Add BPF_PROG_BIND_MAP syscall

On Fri, Aug 28, 2020 at 12:37 PM Stanislav Fomichev <sdf@...gle.com> wrote:
>
> From: YiFei Zhu <zhuyifei@...gle.com>
>
> This syscall binds a map to a program. -EEXIST if the map is
> already bound to the program.
>
> Cc: YiFei Zhu <zhuyifei1999@...il.com>
> Signed-off-by: YiFei Zhu <zhuyifei@...gle.com>
> Signed-off-by: Stanislav Fomichev <sdf@...gle.com>
> ---
>  include/uapi/linux/bpf.h       |  7 ++++
>  kernel/bpf/syscall.c           | 65 ++++++++++++++++++++++++++++++++++
>  tools/include/uapi/linux/bpf.h |  7 ++++
>  3 files changed, 79 insertions(+)
>

[...]

> +
> +       mutex_lock(&prog->aux->used_maps_mutex);
> +
> +       used_maps_old = prog->aux->used_maps;
> +
> +       for (i = 0; i < prog->aux->used_map_cnt; i++)
> +               if (used_maps_old[i] == map) {
> +                       ret = -EEXIST;
> +                       goto out_unlock;

Do we need to return any error in this case? The intent of this
command is to make sure the map is bound to the prog, right? If it's
already bound, good, it's a success, just no extra steps were
performed internally. What's the use for this EEXIST if it's always
going to be ignored?

> +               }
> +
> +       used_maps_new = kmalloc_array(prog->aux->used_map_cnt + 1,
> +                                     sizeof(used_maps_new[0]),
> +                                     GFP_KERNEL);
> +       if (!used_maps_new) {
> +               ret = -ENOMEM;
> +               goto out_unlock;
> +       }
> +

[...]

Powered by blists - more mailing lists