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Message-ID: <145a91c7044c08928646f65850a518febcf5a5ca.camel@linux.ibm.com>
Subject: Re: [PATCH v3] ima: detect changes to the backing overlay file
From:   Mimi Zohar <zohar@linux.ibm.com>
To:     Raul Rangel <rrangel@chromium.org>
Cc:     linux-integrity@vger.kernel.org, linux-kernel@vger.kernel.org,
        Eric Snowberg <eric.snowberg@oracle.com>,
        Amir Goldstein <amir73il@gmail.com>
Date:   Wed, 25 Oct 2023 11:09:28 -0400
In-Reply-To: <CAHQZ30BSD2c4WwUTARx9OeqTjusgq7te8OzwdUi6Qk+L=9vSgA@mail.gmail.com>
References: <20231025143906.133218-1-zohar@linux.ibm.com>
         <CAHQZ30BSD2c4WwUTARx9OeqTjusgq7te8OzwdUi6Qk+L=9vSgA@mail.gmail.com>
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On Wed, 2023-10-25 at 08:59 -0600, Raul Rangel wrote:
> On Wed, Oct 25, 2023 at 8:39 AM Mimi Zohar <zohar@linux.ibm.com> wrote:
> > +               if (!IS_I_VERSION(backing_inode) ||
> > +                   backing_inode->i_sb->s_dev != iint->real_dev ||
> > +                   backing_inode->i_ino != iint->real_ino ||
> > +                   !inode_eq_iversion(backing_inode, iint->version)) {
> > +                       iint->flags &= ~IMA_DONE_MASK;
> > +                       iint->measured_pcrs = 0;
> > +               }
> > +       }
> > +
> Does this mean I need to mount ext4 with `-o iversion`? Or has it been
> enabled by default?

According to commit 1ff20307393e ("ext4: unconditionally enable the
i_version counter")  it's now enabled by default.
> 
> I can test this patch out sometime this week and verify it fixes the
> performance regression.
> 
> Thanks!

Much appreciated!

-- 
thanks,

Mimi