Add tempfs experiment and gate mounting behind it

[JoshuaKrstic]

--The binary still needs to be updated.-- Until then, this feature will always be off. Which is fine ofc.

The binary has been updated and the flag exists.

[jkl73]

It's probably the string in printed by the launcher "Mounts:[{Destination:/tmp/sized Size:222}]", together with the "tmpfs" print by the kernel, and some number in the timestamp causing the regex to pass the grep. Maybe adding "^" and "$" to the grep pattern in the test may do the trick.

[alexmwu]

It's probably the string in printed by the launcher "Mounts:[{Destination:/tmp/sized Size:222}]", together with the "tmpfs" print by the kernel, and some number in the timestamp causing the regex to pass the grep. Maybe adding "^" and "$" to the grep pattern in the test may do the trick.

I think we can also try replacing .* with [[:space:]]

[jkl73]

Also we may want to add the flag here instead: https://github.com/google/go-tpm-tools/blob/03c656ef7c4bf335493ea0132e3ae128312202fa/launcher/spec/launch_spec.go#L180

and https://github.com/google/go-tpm-tools/blob/03c656ef7c4bf335493ea0132e3ae128312202fa/launcher/spec/launch_spec.go#L191

[JoshuaKrstic]

/gcbrun

[JoshuaKrstic]

/gcbrun