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Comment by cwaffles | Hacker News Reader

Probability of a bit error increases as memory increases. Opens a large can of worms if control flow breaks.

Yep. 99.9999% correct would mean 8 bit flips per megabyte of data stored in ram. The error rates are (thankfully) much lower than that (otherwise your computer wouldn’t boot). But random bit flips can cause utter havoc if they happen at the wrong time or place. If you download software from the internet, bit flips can introduce weird bugs to your software, only on your computer. (Including in the OS - including your filesystem or drivers). They can corrupt writes to your hard drive, and as a result corrupt your drive or files. Bit flips can quietly change the DNS request your browser sends to cause terrifying security problems. Or edit forms before you send them. There was even a case of a voting machine in Germany accidentally inventing 4096 votes due to a bit flip.

ECC is a really good idea. It’s only expensive right now because it’s a “premium feature”. If it were a standard part of all ram sticks, it’d be cheap and we’d all benefit.

Not argueing against ECC, but some of your scenarios seem to be outdated due to crypto. I.e software you download from the internet is often signed and hashes are validated (Linux package managers, macOS developer certs). Same for DNS requests (dnssec) etc. Yes, there is still wiggle room for bitflips to cause problems, but less so than in the past.

DNSSEC is around the 4~5% mark in .com and .net.

True - my bad of referring to DNSsec; there are other ways you can use encryption for DNS resolving (by using an external DNS server that encrypts using TLS or simply by using DNS-over-HTTPs). This way you get 100% encryption of your DNS traffic (and thus tamper checks that would detect bitflips). Again, not arguing against ECC, there are valid points to want it - I just see less and less reasons in the consumer market.

Encryption and signing don't protect against memory corruption.

For example, I download software from the internet then hash it. The hash matches. Before the bytes are written to disk locally, a bit flips in RAM. The corrupted data is written to disk and used.

Likewise, dnssec doesn't protect you against DNS bitsquatting attacks[1] because the domain name can be changed before the DNS request is made. So the DNS response your computer makes for a-azon.com might be totally valid and signed. It can come through DoH or whatever. The problem is that your browser thought it was the response for amazon.com and chrome send a bitsquatter your amazon cookies. (Oops).

[1] https://www.youtube.com/watch?v=9WcHsT97suU

Well aware of all of that, but it decreases the chances if corruption (ie no corruption during download).

news.ycombinator.com not included in this 4% either

Reply on news.ycombinator.com