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Message-ID: <45a9c575-0b7e-f66a-4765-884865d14b72@linux.ibm.com>
Date:   Thu, 6 Apr 2023 15:11:37 -0400
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Subject: Re: [PATCH] overlayfs: Trigger file re-evaluation by IMA / EVM after
 writes
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To:     Jeff Layton <jlayton@kernel.org>,
        Christian Brauner <brauner@kernel.org>,
        Paul Moore <paul@paul-moore.com>
Cc:     zohar@linux.ibm.com, linux-integrity@vger.kernel.org,
        miklos@szeredi.hu, linux-kernel@vger.kernel.org,
        linux-security-module@vger.kernel.org,
        linux-fsdevel@vger.kernel.org, linux-unionfs@vger.kernel.org,
        amir73il@gmail.com
References: <20230405171449.4064321-1-stefanb@linux.ibm.com>
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 <546145ecbf514c4c1a997abade5f74e65e5b1726.camel@kernel.org>
From:   Stefan Berger <stefanb@linux.ibm.com>
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On 4/6/23 14:46, Jeff Layton wrote:
> On Thu, 2023-04-06 at 17:01 +0200, Christian Brauner wrote:
>> On Thu, Apr 06, 2023 at 10:36:41AM -0400, Paul Moore wrote:

> 
> Correct. As long as IMA is also measuring the upper inode then it seems
> like you shouldn't need to do anything special here.

Unfortunately IMA does not notice the changes. With the patch provided in the other email IMA works as expected.

>
> What sort of fs are you using for the upper layer?

jffs2:

/dev/mtdblock4 on /run/initramfs/ro type squashfs (ro,relatime,errors=continue)
/dev/mtdblock5 on /run/initramfs/rw type jffs2 (rw,relatime)
cow on / type overlay (rw,relatime,lowerdir=run/initramfs/ro,upperdir=run/initramfs/rw/cow,workdir=run/initramfs/rw/work)

Regards,
    Stefan