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> Out-of-bounds and use-after-free can be dealt with by having good coding strategies You're basically saying that every project in the wild has bad “coding st

> Out-of-bounds and use-after-free can be dealt with by having good coding strategies You're basically saying that every project in the wild has bad “coding strategy”… > I expect that we will have full bounds safety options in compilers soon Which will be disabled in most places because of the overhead it incurs. > But having a good ownership model and good abstractions also avoids most problems here in my experience. I rarely have actual problems in my projects related to this. It's easier said than done when you have no way of enforcing the ownership, and practically intractable when not working alone on a codebase.

uecker 2y ago
No, I am not saying that every project in the wild has a bad "coding strategy". Some of the most reliable software I use everyday is written in C. Some of this I use for decades without every encountering a crash or similar bug. So the meme that "all C code crashes all the time because of UB" is clearly wrong. It is not intractable, in my experience you just have to document some rules and occasionally make sure they are followed. But I agree that a formal system to enforce ownership is desirable.
- littlestymaar 2y ago
  > So the meme that "all C code crashes all the time because of UB" is clearly wrong. It's not about crash at all, but “all software has security vulnerabilities because of UB” is unfortunately true. > It is not intractable, in my experience you just have to document some rules and occasionally make sure they are followed. If even DJB couldn't get that part perfectly I'm pretty certain you cannot either.
  - davrosthedalek 2y ago
    Not all software is security relevant. I run a lot of large simulations. I do not care at all if that software would crash on specially prepared inputs. I do care that it's as fast as possible.
    - uecker 2y ago
      Right and there are other ways to achieve strong security guarantees than memory safety, e.g. at the OS level by sandboxing critical operations.
      - littlestymaar 2y ago
        1. It's much more expensive that using a memory-safe language in the first place (maybe cheaper it if you have a big codebase already, but still very expensive and not worth it at all for new code) 2. Sandbox escapes are commonplace, and not everything can even be sandboxed at all.
    - littlestymaar 2y ago
      > Not all software is security relevant You're right, only software that has actual users cares about security. > I run a lot of large simulations. I do not care at all if that software would crash on specially prepared inputs. But it's not the 50s anymore and digital simulation is a tiny fraction of the code ever written nowadays so it's not a very good argument. > I do care that it's as fast as possible. You don't realize it but it ruins your entire argument. If speed is all that matters for your use-case then: - there's no way you can use runtime bound-checks, and you unconditionally need the compiler to optimize as much as possible around UB, even if it breaks your program every once in a while. - you likely can't afford dynamic memory allocation, which makes the UAF/double free kind of bugs irrelevant. Not out of “good coding strategy” but because you never free in the first place… These are hypothesis that don't apply to software industry at large.

uecker 2y ago

No, I am not saying that every project in the wild has a bad "coding strategy". Some of the most reliable software I use everyday is written in C. Some of this I use for decades without every encountering a crash or similar bug. So the meme that "all C code crashes all the time because of UB" is clearly wrong. It is not intractable, in my experience you just have to document some rules and occasionally make sure they are followed. But I agree that a formal system to enforce ownership is desirable.

littlestymaar 2y ago
> So the meme that "all C code crashes all the time because of UB" is clearly wrong. It's not about crash at all, but “all software has security vulnerabilities because of UB” is unfortunately true. > It is not intractable, in my experience you just have to document some rules and occasionally make sure they are followed. If even DJB couldn't get that part perfectly I'm pretty certain you cannot either.
- davrosthedalek 2y ago
  Not all software is security relevant. I run a lot of large simulations. I do not care at all if that software would crash on specially prepared inputs. I do care that it's as fast as possible.
  - uecker 2y ago
    Right and there are other ways to achieve strong security guarantees than memory safety, e.g. at the OS level by sandboxing critical operations.
    - littlestymaar 2y ago
      1. It's much more expensive that using a memory-safe language in the first place (maybe cheaper it if you have a big codebase already, but still very expensive and not worth it at all for new code) 2. Sandbox escapes are commonplace, and not everything can even be sandboxed at all.
  - littlestymaar 2y ago
    > Not all software is security relevant You're right, only software that has actual users cares about security. > I run a lot of large simulations. I do not care at all if that software would crash on specially prepared inputs. But it's not the 50s anymore and digital simulation is a tiny fraction of the code ever written nowadays so it's not a very good argument. > I do care that it's as fast as possible. You don't realize it but it ruins your entire argument. If speed is all that matters for your use-case then: - there's no way you can use runtime bound-checks, and you unconditionally need the compiler to optimize as much as possible around UB, even if it breaks your program every once in a while. - you likely can't afford dynamic memory allocation, which makes the UAF/double free kind of bugs irrelevant. Not out of “good coding strategy” but because you never free in the first place… These are hypothesis that don't apply to software industry at large.