Re: mapping with --readonly option

You probably should mount it as readonly instead. Because
that gets remounted in the typical boot-process as r/w
so it definitely is possible.

If you want protection against a malicious root, this is
probably not the way to go, I think.

Regards,
Arno


On Sat, Nov 05, 2022 at 11:15:12 CET, Fourhundred Thecat wrote:
> Hello,
> 
> if I use the --readonly option to create a mapping, and mount it as my
> root partition, can the mapping later be changed during runtime to
> read-write ?
> 
> Or, in other words, if mapping was created as readonly, can I be sure
> that it cannot be remapped to read-write while being mounted as my root
> filesystem?
> 
> Ofcourse mapping can be closed and opened again, but I am asking here
> specifically for mapping that is mounted as root filesystem, which
> cannot be unmounted at runtime (as far as I know)
> 
> I am interested whether I can use readonly mapping as sort of security
> feature to enforce read-only filesystem?
> 
> thank you

-- 
Arno Wagner,     Dr. sc. techn., Dipl. Inform.,    Email: [email protected]
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