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From: Miklos Szeredi <miklos@szeredi.hu>
Date: Tue, 16 Apr 2024 16:46:59 +0200
Message-ID: <CAJfpeguzh6VzhdnwOPf_hM4x0FbsK8hhZp=VK4kWpCYn0xeBCg@mail.gmail.com>
Subject: Re: [RFC 2/2] ima: Fix detection of read/write violations on stacked filesystems
To: Mimi Zohar <zohar@linux.ibm.com>
Cc: Stefan Berger <stefanb@linux.ibm.com>, Amir Goldstein <amir73il@gmail.com>, 
	linux-integrity@vger.kernel.org, linux-unionfs@vger.kernel.org, 
	linux-kernel@vger.kernel.org, roberto.sassu@huawei.com, 
	Christian Brauner <brauner@kernel.org>
Content-Type: text/plain; charset="UTF-8"

On Tue, 16 Apr 2024 at 14:18, Mimi Zohar <zohar@linux.ibm.com> wrote:
> Originally there was a single measureent unless the filesystem was mounted with
> SB_I_VERSION.  With commit a2a2c3c8580a ("ima: Use i_version only when
> filesystem supports it") this changed to always re-measure the file if the
> filesystem wasn't mounted with SB_I_VERSION.

Does the i_version get stored and compared only while the inode is in memory?

In that case I think it should be possible to support a version number
for the overlay inode.

Thanks,
Miklos