Gabriele Svelto (gabriele.svelto.delete@this.gmail.com) on July 10, 2021 12:51 pm wrote:
> cqwrteur (euloanty.delete@this.live.com) on July 9, 2021 9:56 pm wrote:
> > I just read the upcoming Rust code for Linux Kernel from Github. Maybe I am stupid.
> > What I see is just unsafe everywhere. All Rust functions are unsafe.
>
> That crate - alloc - is part of the standard library that's being ported to the Linux kernel in
> order to be used. Since it implements allocators, collections, smart/refcount pointers and such,
> a small part of it requires the use of the unsafe keyword. This is low-level plumbing, it doesn't
> get any lower level than this in Rust. If you have a more thorough look you'll notice that the
> unsafe sections are surprisingly few compared to the overall size of this particular piece of
> the std library. It also makes sense that you'll find all of them here, because that's how you
> encapsulate unsafe usage in a way that presents safe semantics to the outside world.
>
> Last but not least this code - being ported from the standard library - is used in thousands of different
> projects which makes it pretty well tested. To put a hard number on that 11 CVEs were filed this year against
> Rust's standard library. 3 of them affect only very old versions of it, 2 affect old-but-not-very-old versions
> and 3 more can only happen during panics which I doubt will be allowed in the kernel. That leaves only
> 3 CVEs that affected the current version and did not involve panics; not bad for a library that's several
> times larger than your average C and C++ standard libraries combined and much younger.

You do not just copy paste from rust std to linux kernel. You add code for dual error reporting. Those code are completely unverified due to "panic not allowed policy".

Also. Entire project is unsafe hell. No just the std crates part but other parts too.
https://github.com/Rust-for-Linux/linux/blob/rust/rust/kernel/allocator.rs

You are arguing C and C++ are same languages? No. C clearly has much more CVEs than C++ in general. You said C and C++ "combined" that does not make any sense. They are not the same language.

https://www.cvedetails.com/vendor/15519/Cryptopp.html

What about cryptopp?? No memory safety CVEs at all compared to OpenSSL.

If using Rust does not bring any benefit over modern C++, there is no point due to all the troubles Rust would introduce (like no panic policy whatever).