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Date:   Fri, 2 Apr 2021 12:01:05 -0700
From:   Kees Cook <keescook@chromium.org>
To:     Christoph Hellwig <hch@lst.de>
Cc:     Al Viro <viro@zeniv.linux.org.uk>, linux-fsdevel@vger.kernel.org,
        linux-kernel@vger.kernel.org,
        Andy Lutomirski <luto@amacapital.net>,
        Will Drewry <wad@chromium.org>
Subject: Re: [PATCH] fs: split receive_fd_replace from __receive_fd
Message-ID: <202104021157.7B388D1B2@keescook>
References: <20210325082209.1067987-1-hch@lst.de>
 <20210325082209.1067987-2-hch@lst.de>
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On Thu, Mar 25, 2021 at 09:22:09AM +0100, Christoph Hellwig wrote:
> receive_fd_replace shares almost no code with the general case, so split
> it out.  Also remove the "Bump the sock usage counts" comment from
> both copies, as that is now what __receive_sock actually does.
> 
> Signed-off-by: Christoph Hellwig <hch@lst.de>

I'm okay with repeating code in fs/file.c. What I wanted to avoid was
open coded combinations in various callers.

So, sure, this can be split, but as-is the patch breaks SECCOMP_IOCTL_NOTIF_ADDFD:
https://lore.kernel.org/linux-fsdevel/20210329071939.GC3633@xsang-OptiPlex-9020/

-Kees

-- 
Kees Cook