221–230 of 277 posts
Earlier quoted context omitted.
Data diodes. Call me when you bypass them, I have a job for you.
Data dioses don't prevent malicious data that exploits vulnerabilities and takes over from being transmitted, they only prevent the malware from communicating back.
Earlier quoted context omitted.
I've done security auditing of ADA and C avionics code. (including for DAL-A components). As a language, I'd take Rust any day (in terms of security/robustness properties). However, the rust/LLVM compiler pipeline is nowhere near mature enough for use in high-criticality environments.
I'd take a compiler backend that compiles large parts of the modern software ecosystem every day and has countless programmers using it over some niche compiler that is used only for a vanishing fraction of all applications but boasts some kind of official stamp of applicability in safety relevant contexts.
Behold, LLVM and GCC both miscompile the same numerical code involving mildly tricky aliasing constraints. https://github.com/rust-lang/rust/issues/54878#issuecomment-...
I think I'd prefer that safety-critical code be written in languages that don't allow pointer arithmetic except in scenarios that can be proved via static analysis not to introduce multiple memory aliases. Expecting program writers and compiler authors to get these sorts of things right in C/C++ is just unreasonable.
My $0.02: I came across Boeing's documentation for their "Boeing Update" solution. (think Windows Update, but for 787s). It described in detail how the planes are updated with new firmware for the avionics, entertainment system, and the engines. I was shocked to learn that the 787 uses a lot of COTS kit internally, such as standard WiFi and Ethernet connections. There's an RJ-45 jack at the front landing gear accessi…
Do you have a link to this document/set of documents? If they're what you indicate, I'd love to read them - they sound fascinating.
I feel like this is the kind of thing that would've been completely ignored by everybody except for a handful of concerned hackers had it not been for the recent media outrage against Boeing (and in my opinion absolutely deserved). I guess the question is how bad is it (from the article it's hard to tell exactly, but it sure doesn't sound great)? And another question is how many of our systems that we rely on, from b…
I can tell you traffic lights are extremely insecure. Last month there was a traffic light that was turned the wrong way, such that it was impossible to tell if the light was green. So I climbed the poll and turned it to the right direction. Another fellow pedastrian thanked me. A bad actor could do anything from a DOS (positioning it the wrong direction) to tampering with the bulbs (for example swapping out all the…
Traffic authorities use coloured bulbs where you are? Weird.
Where I am, as far as I'm aware the colours always come from a gel in front of the lamp. Furthermore, the red lamp holder is larger than the green and amber ones.
Earlier quoted context omitted.
Offhand thought of the day. The Motor Industry Software Reliability Association should ban compilers that allow optimization based in UB. Because seriously these people need to be stopped.
UB was invented for the purpose of optimizing. No UB, no optimizing. And nobody is interested in funding or working on compilers that don't optimize. Anyway, just test with ubsan and you'll be good.
[0] https://www.cs.utah.edu/~regehr/papers/undef-pldi17.pdf
[1] https://benchmarksgame-team.pages.debian.net/benchmarksgame/...
* Some is inherited from LLVM, some is bugs, some is dumb corner cases like using kernel syscalls to overwrite the program's own memory with random bits.
Earlier quoted context omitted.
Data diodes. Call me when you bypass them, I have a job for you.
Data dioses don't prevent malicious data that exploits vulnerabilities and takes over from being transmitted, they only prevent the malware from communicating back.
My $0.02: I came across Boeing's documentation for their "Boeing Update" solution. (think Windows Update, but for 787s). It described in detail how the planes are updated with new firmware for the avionics, entertainment system, and the engines. I was shocked to learn that the 787 uses a lot of COTS kit internally, such as standard WiFi and Ethernet connections. There's an RJ-45 jack at the front landing gear accessi…
Reading that just makes me think about how "wild west" self-driving cars seem to be, and most people seem to think that's acceptable. We have Teslas that don't have anywhere near this kind of security or redundancy "autopiloting" themselves right now on highways. People seem to be ok with that because it's a car and not a plane. But the way I see it, there's thousands of those cars on the roads, and a software bug ac…
Not just Teslas, modern vehicles in general. I would say that in terms of security Tesla is probably doing a more bang-up job than the other automakers; it was only a few years ago that Charlie Miller and Chris Valasek remotely killed a Grand Cherokee on the highway.
I feel like this is the kind of thing that would've been completely ignored by everybody except for a handful of concerned hackers had it not been for the recent media outrage against Boeing (and in my opinion absolutely deserved). I guess the question is how bad is it (from the article it's hard to tell exactly, but it sure doesn't sound great)? And another question is how many of our systems that we rely on, from b…
I can tell you traffic lights are extremely insecure. Last month there was a traffic light that was turned the wrong way, such that it was impossible to tell if the light was green. So I climbed the poll and turned it to the right direction. Another fellow pedastrian thanked me. A bad actor could do anything from a DOS (positioning it the wrong direction) to tampering with the bulbs (for example swapping out all the…
Earlier quoted context omitted.
I'd take a compiler backend that compiles large parts of the modern software ecosystem every day and has countless programmers using it over some niche compiler that is used only for a vanishing fraction of all applications but boasts some kind of official stamp of applicability in safety relevant contexts.
I'm not so sure I would. For one, Ada is in no way a niche language. For two, C (and C++ by extension) simply were not designed with safety or reliability in mind. I happen to think that it's fair to say that they weren't designed at all, in that C compilers existed before the first language specification, and the language specification was forced to accommodate their quirks. Cargo culting about C is fine and all, bu…
I'd argue that you would probably never find a bug such as that in a certified compiler, not because of the certification, but because far, far fewer eyes look at its output. I have worked in safety critical software and used a certified compiler. It had enough bugs that I personally found four in my first year.