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From: Miklos Szeredi <miklos@szeredi.hu>
Date: Mon, 11 Mar 2024 10:25:20 +0100
Message-ID: <CAJfpegtQSi0GFzUEDqdeOAq7BN2KvDV8i3oBFvPOCKfJJOBd2g@mail.gmail.com>
Subject: Re: [PATCH v2 3/3] ovl: fix the parsing of empty string mount parameters
To: Luis Henriques <lhenriques@suse.de>
Cc: "Theodore Ts'o" <tytso@mit.edu>, Andreas Dilger <adilger.kernel@dilger.ca>, 
	Alexander Viro <viro@zeniv.linux.org.uk>, Christian Brauner <brauner@kernel.org>, Jan Kara <jack@suse.cz>, 
	Amir Goldstein <amir73il@gmail.com>, linux-ext4@vger.kernel.org, 
	linux-fsdevel@vger.kernel.org, linux-unionfs@vger.kernel.org, 
	linux-kernel@vger.kernel.org
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On Thu, 7 Mar 2024 at 19:17, Luis Henriques <lhenriques@suse.de> wrote:
>
> This patch fixes the usage of mount parameters that are defined as strings
> but which can be empty.  Currently, only 'lowerdir' parameter is in this
> situation for overlayfs.  But since userspace can pass it in as 'flag'
> type (when it doesn't have a value), the parsing will fail because a
> 'string' type is assumed.

I don't really get why allowing a flag value instead of an empty
string value is fixing anything.

It just makes the API more liberal, but for what gain?

Thanks,
Miklos