From: Demi Marie Obenour <demiobenour@gmail.com>
To: Alyssa Ross <hi@alyssa.is>
Cc: Spectrum OS Development <devel@spectrum-os.org>
Subject: Re: Why is /run/vm/by-id/${VM} writable by the VMM?
Date: Mon, 13 Jul 2026 13:00:11 -0400 [thread overview]
Message-ID: <0d8076ca-dd4d-42c2-9806-0f78841ae397@gmail.com> (raw)
In-Reply-To: <87ech71crf.fsf@alyssa.is>
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On 7/13/26 05:04, Alyssa Ross wrote:
> Demi Marie Obenour <demiobenour@gmail.com> writes:
>
>> This seems to be a fairly significant hole in the VMM's sandbox.
>> Various code operates in that directory and isn't secure against
>> symlink attacks.
>>
>> Does the VMM really need write access to that directory? Could it
>> be given access to a subdirectory that is mounted "nosymfollow"?
>
> I think it's just so it can create e.g. the serial file. That could
> indeed be moved to a subdirectory. The ideal solution is of course for
> Cloud Hypervisor to be able to accept every file it would otherwise
> create as an open file descriptor, which I expect will happen
> eventually.
Should it be moved to a subdirectory for now? That would make the
sandbox meaningful in practice.
--
Sincerely,
Demi Marie Obenour (she/her/hers)
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next prev parent reply other threads:[~2026-07-13 17:00 UTC|newest]
Thread overview: 8+ messages / expand[flat|nested] mbox.gz Atom feed top
2026-07-11 19:04 Why is /run/vm/by-id/${VM} writable by the VMM? Demi Marie Obenour
2026-07-13 9:04 ` Alyssa Ross
2026-07-13 17:00 ` Demi Marie Obenour [this message]
2026-07-15 18:54 ` Alyssa Ross
2026-07-16 17:06 ` Demi Marie Obenour
2026-07-21 16:05 ` Alyssa Ross
2026-07-21 20:11 ` Demi Marie Obenour
2026-07-22 8:18 ` Alyssa Ross
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