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Date: Thu, 8 Feb 2024 16:50:49 -0500
From: Oliver Crumrine <ozlinuxc@gmail.com>
To: Stanislav Fomichev <sdf@google.com>
Cc: bpf@vger.kernel.org, linux-kernel@vger.kernel.org
Subject: Re: [PATCH] net: remove check before __cgroup_bpf_run_filter_skb
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On Thu, Feb 08, 2024 at 04:43:06PM -0800, Stanislav Fomichev wrote:
> The check is here to make sure we only run this hook on non-req sockets.
> Dropping it would mean we'd be running the hook on the listeners
> instead. I don't think we want that.

You are correct that we don't want to run the code on listeners. However
the check for that is in the function this macro calls,
__cgroup_bpf_run_filter_skb (the check is on line 1367 of
kernel/bpf/cgroup.c, for 6.8.0-rc3). The check doesn't need to be done
twice, so it can be removed in this macro.