netdev - Re: [PATCH net-next 2/4] tools: ynl: allow setting recv() size

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 linux-cve-announce 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]

Message-ID: <CAD4GDZzkVJackAf2yhG1E5vypd2J=n23HD5Huu356JK1F1oLKA@mail.gmail.com>
Date: Mon, 4 Mar 2024 13:38:51 +0000
From: Donald Hunter <donald.hunter@...il.com>
To: Jakub Kicinski <kuba@...nel.org>
Cc: davem@...emloft.net, netdev@...r.kernel.org, edumazet@...gle.com, 
	pabeni@...hat.com, jiri@...nulli.us
Subject: Re: [PATCH net-next 2/4] tools: ynl: allow setting recv() size

On Fri, 1 Mar 2024 at 23:05, Jakub Kicinski <kuba@...nel.org> wrote:
>
>  class YnlFamily(SpecFamily):
> -    def __init__(self, def_path, schema=None, process_unknown=False):
> +    def __init__(self, def_path, schema=None, process_unknown=False,
> +                 recv_size=131072):

An aside: what is the reason for choosing a 128k receive buffer? If I
remember correctly, netlink messages are capped at 32k.

>          super().__init__(def_path, schema)
>
>          self.include_raw = False
> @@ -423,6 +428,16 @@ genl_family_name_to_id = None
>          self.async_msg_ids = set()
>          self.async_msg_queue = []
>
> +        # Note that netlink will use conservative (min) message size for
> +        # the first dump recv() on the socket, our setting will only matter

I'm curious, why does it behave like this?

> +        # from the second recv() on.
> +        self._recv_size = recv_size