Is it possible to make ext4 images reproducible even after filesystem operations ?

[Chris Lamb]

Hi Adithya,

> In the project that I am working on, there are some mount operations 
> done on the filesystem to copy certain files into the file system. This 
> updates the "Last mount" and "Last write" timestamps in the filesystem 
> metadata (confirmed this with dumpe2fs) thereby making the images 
> generated not reproducible.

These are fields in the filesystem's superblock, and the only way I know
of not updating them is to mount the filesystem read-only... which isn't
very helpful for you.

Perhaps you can do something hacky like forcibly reverting to a backup
superblock... but that might not even do the right thing. Can I suggest
emailing linux-ext4 at vger.kernel.org? They might have a neat solution.


Best wishes,

-- 
      o
    ⬋   ⬊      Chris Lamb
   o     o     reproducible-builds.org 💠
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