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Date:   Mon, 18 Sep 2023 17:22:20 +0200
From:   Christian Brauner <brauner@kernel.org>
To:     Miklos Szeredi <miklos@szeredi.hu>
Cc:     Miklos Szeredi <mszeredi@redhat.com>,
        Linus Torvalds <torvalds@linux-foundation.org>,
        linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org,
        linux-api@vger.kernel.org, linux-man@vger.kernel.org,
        linux-security-module@vger.kernel.org, Karel Zak <kzak@redhat.com>,
        Ian Kent <raven@themaw.net>,
        David Howells <dhowells@redhat.com>,
        Al Viro <viro@zeniv.linux.org.uk>,
        Christian Brauner <christian@brauner.io>,
        Amir Goldstein <amir73il@gmail.com>
Subject: Re: [RFC PATCH 2/3] add statmnt(2) syscall
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> So to be clear about your proposal: .mnt_root and .mountpoint are
> initialized by the caller to buffers that the kernel can copy paths
> into?

Yeah, u64 pointer to a buffer and a size (see e.g., @set_tid and
@set_tid_size for struct clone_args, @log_buf and @log_size and other
args in there).

> 
> If there's an overflow (one of the buffers was too small) the syscall
> returns -EOVERFLOW?

Yeah, I mean we have to make some things their problem.

To me that is an acceptable compromise.