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Calling NSA to find your encryption key after a few bits were flipped (2010)

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Re: Calling NSA to find your encryption key after a few bits were flipped (2010)

#81

Post by nyolfen »

nix23 wrote: post #35
daniel-cussen wrote: post #22

Earlier quoted context omitted.

I have super bivalent opinions about Intel. This is the opposite of ambivalent, it means heavily charged in both directions, but cancellation is not allowed. So that's why they should have let all their chips do ECC instead of making it a premium feature, it would have been better for their brand as "Chipzilla" and had no real cost. And it's dangerous! In fact a soft-error at sea level killed an operating system upda…

It's your error, having a system with important data no actual/realtime backup no second system and no plan to recover from a failed update and no ecc is YOUR error alone. However, intel should have made ecc the standard and not just for 1000$+ Xeons.

ryzen pro supports ecc now, fwiw

Re: Calling NSA to find your encryption key after a few bits were flipped (2010)

#82

Post by willis936 »

hedora wrote: post #72
willis936 wrote: post #18

Earlier quoted context omitted.

This is taken care of at the filesystem level.

That's physically impossible. Silent corruption can always happen between the point in time when the data is generated and when the filesystem checksums it. Modern hardware tries to detect these sorts of things and halt before the corruption is propagated. Sometimes it succeeds, sometimes it does not. The best checksums can reliably do is point at the software/hardware component that is at fault.

What are you talking about? Because it isn't a tape-writing machine.

Re: Calling NSA to find your encryption key after a few bits were flipped (2010)

#83

Post by 310260 »

This is a someone common problem with solar flares and cellular base stations. Bit flips cause odd configurations to show up, sites to become sleepy, or even just straight up go off-air. A simple reset fixes them but it happens more often than you might expect.

Re: Calling NSA to find your encryption key after a few bits were flipped (2010)

#84

Post by duskwuff »

lostlogin wrote: post #27
captn3m0 wrote: post #15

Earlier quoted context omitted.

Happens even on end user browsers resulting in bit-flipped domains being looked up: https://securitee.org/files/bitsquatting_www2013.pdf

Bitsquatting is a great name. I’m not 100% that this isn’t just typosquatting though.

It isn't simple typosquatting because it can involve errors that aren't plausible typos (like "mic2osoft.com" for "microsoft.com"), or domains that a user would never enter manually (like "fbcdn.com" or "ytimg.com", which are used for content delivery at Facebook and YouTube, respectively).

Re: Calling NSA to find your encryption key after a few bits were flipped (2010)

#85

Post by necovek »

sodality2 wrote: post #43
yeetsfromhellL2 wrote: post #16

Earlier quoted context omitted.

To protect against bit flips in car fly-by-wire systems, each signal is sent three times with the 2/3 majority making the decision. This happened after the runaway Prius fiasco that may have been caused by a gamma ray. Prior to that incident the fly-by-wire system only sent one signal.

This is really inefficient, two bitflips in the same location will result in a bitflip. For 3x the space surely there's a more resilient scheme that can handle more.

It's not only about memory size, but the speed of processing too.

Higher level protocols would signal an error, and require a retransmission until no error is detected.

However, "majority rule" does indeed sound like an error checking mechanism designed by a non-engineer (or non-mathematician) commitee.

Re: Calling NSA to find your encryption key after a few bits were flipped (2010)

#86

Post by shakna »

willis936 wrote: post #46
jaytaylor wrote: post #37

Earlier quoted context omitted.

Which filesystems support this degree of integrity checking? Presumably ZFS, but what about EXT4/3, ReiserFS, BTRFS, ZFS, NTFS, and FAT32? It would be wonderful if they all have the feature, but I thought only ZFS was really that paranoid.

ZFS and BTRFS have nice online scrubbing features, but nearly every filesystem these days is journaling, including NTFS and XFS (and its contemporaries). Journaling means every block has a checksum. Sure, FAT32 doesn't have that, but no one should ever have the expectation of data integrity on FAT32. You can run checkdisk on journaling filesystems to scrub for errors.

FAT is a requirement of UEFI though, isn't it? So if you can boot from the drive, you can't rely on it to have the filesystem integrity preserved at the disk level.

Re: Calling NSA to find your encryption key after a few bits were flipped (2010)

#87

Post by throwawaylinux »

daniel-cussen wrote: post #22
codeflo wrote: post #12

Bit flips are scary even on Earth. At a previous job, we had a customer who suddenly couldn’t send us email anymore. When their IT sent us the server logs to “prove” it’s our fault, we saw that the one letter in the cached MX record was wrong. This was puzzling, until I looked at the ASCII table to verify that the difference was exactly one bit. We never found out where in the name resolution process the bit got flip…

I have super bivalent opinions about Intel. This is the opposite of ambivalent, it means heavily charged in both directions, but cancellation is not allowed. So that's why they should have let all their chips do ECC instead of making it a premium feature, it would have been better for their brand as "Chipzilla" and had no real cost. And it's dangerous! In fact a soft-error at sea level killed an operating system upda…

You bought a non-ECC part from Intel and some memory from a (different) vendor, and the memory flipped a bit.

Do you have any evidence or reason to believe that memory error was outside the advertised error rate for the device, or due to some other wrongful conduct by the vendor? And how would you connect that to wrongful action by Intel which contributed to your damages?

I'm no lawyer but I suspect your case is not quite the bargaining chip that you seem to believe.

Re: Calling NSA to find your encryption key after a few bits were flipped (2010)

#88

Post by snoshy »

xyzzyz wrote: post #65
smegma2 wrote: post #42

Earlier quoted context omitted.

That code has a race condition :^)

Did you mean ray's condition?

Oddly apropos anecdote to your pun:

About 15 years ago, while working on Windows at Microsoft, a test machine sitting at my desk hit a kernel panic (BSOD). As was standard working on the test team, the machine was already setup for kernel debugging, and so I set out to debug it a bit in order to file a decent bug report.

Hours later, I couldn't make sense of it (I wasn't super experienced at this point). A few of the nearby devs couldn't either, and a small troop of us curious enough about the puzzler eventually escalated to the resident wizard, Raymond Chen[1]. Within 15 minutes of checking our work and poking at the machine, he traced the root cause down to a bit flip.

Ray's condition indeed. :)

[1] https://devblogs.microsoft.com/oldnewthing/

Re: Calling NSA to find your encryption key after a few bits were flipped (2010)

#89

Post by asasidh »

codeflo wrote: post #12

Bit flips are scary even on Earth. At a previous job, we had a customer who suddenly couldn’t send us email anymore. When their IT sent us the server logs to “prove” it’s our fault, we saw that the one letter in the cached MX record was wrong. This was puzzling, until I looked at the ASCII table to verify that the difference was exactly one bit. We never found out where in the name resolution process the bit got flip…

Bit flips sound like glitch in the matrix

Re: Calling NSA to find your encryption key after a few bits were flipped (2010)

#90

Post by elevaet »

snoshy wrote: post #88
xyzzyz wrote: post #65

Earlier quoted context omitted.

Did you mean ray's condition?

Oddly apropos anecdote to your pun: About 15 years ago, while working on Windows at Microsoft, a test machine sitting at my desk hit a kernel panic (BSOD). As was standard working on the test team, the machine was already setup for kernel debugging, and so I set out to debug it a bit in order to file a decent bug report. Hours later, I couldn't make sense of it (I wasn't super experienced at this point). A few of the…

Great story, a true random glitch.

Interestingly, a blog post of his was up on HN front page the other day: "The x86 architecture is the weirdo, part 2" https://news.ycombinator.com/item?id=31077912

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