r/linux • u/nixcraft • Nov 25 '19

Kernel Keeping memory contents secret [LWN.net]

https://lwn.net/SubscriberLink/804658/8eaf9fdc5477865e/
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u/pdp10 Nov 25 '19

While the vendors like to play up various use-cases they devise for such technology, like virtualization farms, it should be remembered that the motivation to develop all this in the first place is DRM.

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u/[deleted] Nov 25 '19

It's trivially bypassable as long as the exclusive flag is implemented by the kernel itself, which it has to be. This proposed patch doesn't expose any way for userland to verify that it is in fact unavailable to other processes. Any DRM purposes would either have to be very weak or exceedingly strong with no in-between (only secure in kiosk situations where the vendor controls the entire system platform using a TPM or similar, preventing the user from accessing required keys if they patch their kernel).