mem-isolate is a Rust crate designed to execute potentially unsafe code within isolated memory compartments. It leverages Linux's memfd_create system call to create anonymous memory mappings, allowing developers to run untrusted code within these confined regions, limiting the potential damage from vulnerabilities or exploits. This sandboxing approach helps mitigate security risks by restricting access to the main process's memory, effectively preventing malicious code from affecting the wider system. The crate offers a simple API for setting up and managing these isolated execution environments, providing a more secure way to interact with external or potentially compromised code.
Crabtime brings Zig's comptime functionality to Rust, enabling evaluation of functions and expressions at compile time. It utilizes a procedural macro to transform annotated Rust code into a syntax tree that can be executed during compilation. This allows for computations, including string manipulation, type construction, and resource embedding, to be performed at compile time, leading to improved runtime performance and reduced binary size. Crabtime is still early in its development but aims to provide a powerful mechanism for compile-time metaprogramming in Rust.
HN commenters discuss crabtime, a library bringing Zig's comptime functionality to Rust. Several express excitement about the potential for metaprogramming and compile-time code generation, viewing it as a way to achieve greater performance and flexibility. Some raise concerns about the complexity and potential misuse of such powerful features, comparing it to template metaprogramming in C++. Others question the practical benefits and wonder if the added complexity is justified. The potential for compile times to increase significantly is also mentioned as a drawback. A few commenters suggest alternative approaches, like using build scripts or procedural macros, though the author clarifies that crabtime aims to offer something distinct. The overall sentiment seems to be cautious optimism, with many intrigued by the possibilities but also aware of the potential pitfalls.
This project introduces lin-alg, a Rust library providing fundamental linear algebra structures and operations with a focus on performance. It offers core types like vectors and quaternions (with 2D, 3D, and 4D variants), alongside common operations such as addition, subtraction, scalar multiplication, dot and cross products, normalization, and quaternion-specific functionalities like rotations and spherical linear interpolation (slerp). The library aims to be simple, efficient, and dependency-free, suitable for graphics, game development, and other domains requiring linear algebra computations.
Hacker News users generally praised the Rust vector and quaternion library for its clear documentation, beginner-friendly approach, and focus on 2D and 3D graphics. Some questioned the practical application of quaternions in 2D, while others appreciated the inclusion for completeness and potential future use. The discussion touched on SIMD support (or lack thereof), with some users highlighting its importance for performance in graphical applications. There were also suggestions for additional features like dual quaternions and geometric algebra support, reflecting a desire for expanded functionality. Some compared the library favorably to existing solutions like glam and nalgebra, praising its simplicity and ease of understanding, particularly for learning purposes.
Summary of Comments ( 5 )
https://news.ycombinator.com/item?id=43601301
Hacker News users discussed the practicality and security implications of the
mem-isolatecrate. Several commenters expressed skepticism about its ability to truly isolate unsafe code, particularly in complex scenarios involving system calls and shared resources. Concerns were raised about the performance overhead and the potential for subtle bugs in the isolation mechanism itself. The discussion also touched on the challenges of securely managing memory in Rust and the trade-offs between safety and performance. Some users suggested alternative approaches, such as using WebAssembly or language-level sandboxing. Overall, the comments reflected a cautious optimism about the project but acknowledged the difficulty of achieving complete isolation in a practical and efficient manner.The Hacker News post "Show HN: I built a Rust crate for running unsafe code safely" (linking to the
mem-isolatecrate) generated a moderate amount of discussion, mostly focused on the complexities and nuances of memory safety in Rust, and whether the crate truly offers a "safe" solution for running unsafe code.Several commenters express skepticism about the claim of "safely" running unsafe code. One points out the inherent contradiction, suggesting the term is an oxymoron. Another argues that true safety requires formal verification, and anything short of that is merely reducing the attack surface rather than eliminating it. This sentiment is echoed by another commenter who highlights the difficulty in proving the soundness of the approach and the potential for subtle bugs to undermine the isolation.
A few comments delve into the specifics of
mem-isolate's implementation. One user questions its practicality for real-world scenarios, suggesting that the overhead of serialization and deserialization, coupled with the limitations on system call access, could severely limit its usefulness. They also mention the potential performance impact and the challenge of managing data dependencies between isolated processes.The discussion also touches upon alternative approaches to isolating unsafe code, such as WebAssembly. One commenter mentions Wasmtime as a more mature and robust solution, although they acknowledge that Wasmtime might not be suitable for all use cases. Another suggests using language-level sandboxing features provided by some languages.
Some users discuss the trade-offs between security and performance. One commenter notes that while complete memory safety is desirable, it often comes at a cost to performance. They suggest that in certain situations, a calculated risk with less strict isolation might be acceptable if performance is a critical factor.
Finally, a few comments express general interest in the project and commend the author for tackling a challenging problem. They acknowledge the difficulty of achieving true memory safety in systems programming and appreciate the effort to improve the security of Rust code. However, even these positive comments maintain a cautious tone, reflecting the overall skepticism towards the claim of absolute safety.