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   lcamtuf :verified: :verified: :verified: (lcamtuf@infosec.exchange)'s status on Tuesday, 05-May-2026 04:37:02 JST lcamtuf :verified: :verified: :verified:

   The coreutils Rust rewrite story is pretty funny.

   Coreutils are tools like rm, mv, mkdir, etc. Unlike binutils, this isn't a fertile ground for memory safety bugs. But, the rewrite was completed, and in the spirit of progress, Canonical decided to switch.

   But do you know what coreutils are a fertile ground for? Race conditions around file creation, deletion, permission setting, and so on. The original code accounted for decades of hard-learned lessons in that space. The Rust rewrite did not:

   https://seclists.org/oss-sec/2026/q2/332

   PS. I'm not dunking on Rust. It's just that... starting over from scratch has its hidden costs.

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     Ryan Castellucci (they/them) :nonbinary_flag: (ryanc@infosec.exchange)'s status on Tuesday, 05-May-2026 04:42:40 JST Ryan Castellucci (they/them) :nonbinary_flag:

     in reply to

     @lcamtuf Amusingly, I recently did some work in Rust and wanted safe file operations that avoided race conditions. I couldn't find anything good and wrote my own opinionated helper.

     Though, a large part of it is that O_TMPFILE is awesome and underused.