leofidus / process_consistency Goto Github PK

I'm pretty sure that the current handling of writable sections is unsound. In compute_hash(), you're creating a slice to the section's memory. It has to be assumed that there exist (at least temporarily) mutable references to objects in that section (why would it be writable otherwise?), therefore creating any other aliasing reference to it is instant undefined behaviour. Even if not, any concurrent writes to the section while it is being read are a data race and therefore undefined behaviour as well.

I was going to suggest using volatile reads instead, however the documentation of read_volatile() explicitly states:

In particular, a race between a read_volatile and any write operation to the same location is undefined behavior.

... so this isn't a workaround either.