[NotHereNotThere]

How so? Telsa would most likely communicate with an API on the car and not directly running file hashes remotely.

What prevents an attacker from overriding some validateFile("path","hash") call to always return 0 ?

[fastball]

Because you could ask for a checksum of the firmware and if it doesn't return the right hash you know something isn't right.

You also never store the hash, so once a user has gained access to the car it's impossible to get the right hash (as you would've had to modify the firmware/filesystem/etc in some way to gain entry).

You would also need to include a timestamp/car serial in the hash so that you couldn't reuse an old hash from before your entry (that you had MITM'd) or use a hash from a different car that still had its integrity.