4 ms·

Yep, this is why in Vulnerability Research one of the main ways of finding bugs is concolic execution (Looking at logic for error cases). Memory safety is prett

by maldev 4y ago

Yep, this is why in Vulnerability Research one of the main ways of finding bugs is concolic execution (Looking at logic for error cases). Memory safety is pretty easy to catch if you arn't a clown and use good coding patterns. Logic isn't, which is where the big money and big boy vulns come in. And honestly, most modern OS's have memory safety protections built in. This is 1992 anymore.

buescher 4y ago
Sure, but safety-critical development is a different domain than vulnerability research.
wizofaus 4y ago
"Memory safety is pretty easy to catch" - my experience over the last 18 months or so on a large C++ open source project says very much otherwise, almost every week a new NPE or core dump/access violation seems to leak into the codebase. These simply can't happen in many other languages and many now even have good support for non-optional references, ruling out entire classes of bugs that can suck up significant developer time to track down. And for long running systems memory leaks can also be a substantial cause of instability. If I were working on a safety critical system I'd actively push to avoid using C/C++ unless there really was no alternative. And yes modern OS kernels are pretty good evidence that it is possible to do but I'd suggest it requires exceptional programmers and some very rigorous processes to enforce.
- buescher 4y ago
  Assume you have a functional safety requirement for which a standard exists. What language implementation would you use that is certified for that standard?
  - wizofaus 4y ago
    Not sure how that question can be meaningfully answered unless it's for a specific safety requirement/standard. Are you suggesting that for most standards that require certification, there are no compiler implementations certified except for C/C++ ones?
    - buescher 4y ago
      Try the exercise. Choose one and then choose your tooling. If it's not C, C++, or Ada, I'll be surprised.
      - wizofaus 4y ago
        I had some involvement with development of an air traffic management system, which was being written in Java, as that was certified for use in that field. As a language, I'd rather use C++ over Java, but if safety criticality were the priority, I'd choose Java every time. I haven't coded in Ada but unless there's something about it that's truly awful to work with, it seems a better choice than C/C++ from what I know about it.
speedgoose 4y ago
Yes, memory safety is a solved problem, and research has mostly moved on. The best solution is to use a memory-safe programming language. Yet we find security vulnerabilities all the time in software written with memory unsafe programming languages.

by maldev 4y ago

buescher 4y ago

Sure, but safety-critical development is a different domain than vulnerability research.

wizofaus 4y ago

"Memory safety is pretty easy to catch" - my experience over the last 18 months or so on a large C++ open source project says very much otherwise, almost every week a new NPE or core dump/access violation seems to leak into the codebase. These simply can't happen in many other languages and many now even have good support for non-optional references, ruling out entire classes of bugs that can suck up significant developer time to track down. And for long running systems memory leaks can also be a substantial cause of instability. If I were working on a safety critical system I'd actively push to avoid using C/C++ unless there really was no alternative. And yes modern OS kernels are pretty good evidence that it is possible to do but I'd suggest it requires exceptional programmers and some very rigorous processes to enforce.

buescher 4y ago
Assume you have a functional safety requirement for which a standard exists. What language implementation would you use that is certified for that standard?
- wizofaus 4y ago
  Not sure how that question can be meaningfully answered unless it's for a specific safety requirement/standard. Are you suggesting that for most standards that require certification, there are no compiler implementations certified except for C/C++ ones?
  - buescher 4y ago
    Try the exercise. Choose one and then choose your tooling. If it's not C, C++, or Ada, I'll be surprised.
    - wizofaus 4y ago
      I had some involvement with development of an air traffic management system, which was being written in Java, as that was certified for use in that field. As a language, I'd rather use C++ over Java, but if safety criticality were the priority, I'd choose Java every time. I haven't coded in Ada but unless there's something about it that's truly awful to work with, it seems a better choice than C/C++ from what I know about it.

speedgoose 4y ago

Yes, memory safety is a solved problem, and research has mostly moved on. The best solution is to use a memory-safe programming language. Yet we find security vulnerabilities all the time in software written with memory unsafe programming languages.