<![CDATA[The coreutils Rust rewrite story is pretty funny.]]>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.

]]>https://forum.other.li/topic/9e7bbe4a-12ba-48e1-b3b2-cddd9928ac11/the-coreutils-rust-rewrite-story-is-pretty-funny.RSS for NodeSat, 30 May 2026 09:38:22 GMTMon, 04 May 2026 16:14:48 GMT60<![CDATA[Reply to The coreutils Rust rewrite story is pretty funny. on Mon, 04 May 2026 20:13:58 GMT]]>@david_chisnall @lcamtuf Try to write to C++ ‚cout‘ concurrently. Complete clown fiesta!🤡

]]>https://forum.other.li/post/https://chaos.social/users/icing/statuses/116518134675155406https://forum.other.li/post/https://chaos.social/users/icing/statuses/116518134675155406Mon, 04 May 2026 20:13:58 GMT<![CDATA[Reply to The coreutils Rust rewrite story is pretty funny. on Mon, 04 May 2026 20:06:13 GMT]]>@ireneista @lcamtuf
I guess that could work if you really investigate all the fundamental mistakes, as well as the regular bugs/pitfalls, from the first mistake and try your best to avoid them.

Assuming that "it was written in a less safe language" was the only or even most important issue is.. not that useful

]]>https://forum.other.li/post/https://mastodon.gamedev.place/users/Doomed_Daniel/statuses/116518104147608713https://forum.other.li/post/https://mastodon.gamedev.place/users/Doomed_Daniel/statuses/116518104147608713Mon, 04 May 2026 20:06:13 GMT<![CDATA[Reply to The coreutils Rust rewrite story is pretty funny. on Mon, 04 May 2026 20:06:07 GMT]]>@lcamtuf "The lesson of history is that no one learns."

]]>https://forum.other.li/post/https://mstdn.ca/users/controlc/statuses/116518103769091408https://forum.other.li/post/https://mstdn.ca/users/controlc/statuses/116518103769091408Mon, 04 May 2026 20:06:07 GMT<![CDATA[Reply to The coreutils Rust rewrite story is pretty funny. on Mon, 04 May 2026 20:01:48 GMT]]>@ChuckMcManis addendum: I didn't mean for this to be a "well, actually" statement; I'm not pushing back against your statements, only curious about your experience.

@darkuncle @lcamtuf

]]>https://forum.other.li/post/https://hactivedirectory.com/users/josh/statuses/116518086831833154https://forum.other.li/post/https://hactivedirectory.com/users/josh/statuses/116518086831833154Mon, 04 May 2026 20:01:48 GMT<![CDATA[Reply to The coreutils Rust rewrite story is pretty funny. on Mon, 04 May 2026 20:00:14 GMT]]>@ChuckMcManis I actually find questioning the why behind something to be important. In your experience at Google, did the devs rewriting things have _access_ to the documentation as to why something was done? Was it like disbelief of the stated facts or were there holes in the notetaking about the reasoning?

@darkuncle @lcamtuf

]]>https://forum.other.li/post/https://hactivedirectory.com/users/josh/statuses/116518080673725998https://forum.other.li/post/https://hactivedirectory.com/users/josh/statuses/116518080673725998Mon, 04 May 2026 20:00:14 GMT<![CDATA[Reply to The coreutils Rust rewrite story is pretty funny. on Mon, 04 May 2026 19:56:11 GMT]]>@lcamtuf and then there's... well, there's a persistent feeling that starting over without regard for the past will make things better, rather than just repeating the same fundamental mistake that happened the first time

we've felt it too. it's a powerful pull.

we wrote a bit about that feeling, a while back https://irenes.space/leaves/2024-09-29-technology-community-idealism

]]>https://forum.other.li/post/https://adhd.irenes.space/users/ireneista/statuses/01KQT900TAYF0WDH0RHQNZMT6Whttps://forum.other.li/post/https://adhd.irenes.space/users/ireneista/statuses/01KQT900TAYF0WDH0RHQNZMT6WMon, 04 May 2026 19:56:11 GMT<![CDATA[Reply to The coreutils Rust rewrite story is pretty funny. on Mon, 04 May 2026 19:55:57 GMT]]>@ChuckMcManis @m33 @sten @lcamtuf on the flip side, if you have good discipline around handling change on a continuous basis and operational agility, you can more easily incorporate Werner Vogels' aphorism "everything fails, all the time, plan accordingly"

does that lead to lazy / negligent engineering? maybe?? If the architecture is such that I don't have to care as much about my component failing, maybe we need different metrics to incentivize quality other than "it went down and people got fired"

]]>https://forum.other.li/post/https://infosec.exchange/users/darkuncle/statuses/116518063807256178https://forum.other.li/post/https://infosec.exchange/users/darkuncle/statuses/116518063807256178Mon, 04 May 2026 19:55:57 GMT<![CDATA[Reply to The coreutils Rust rewrite story is pretty funny. on Mon, 04 May 2026 19:52:42 GMT]]>@lcamtuf Dang, that is a wild ride of a thread.

And it kinda lines up with my experiences as well-- coreutils is battle tested and a load bearing feature of Linux.

Uutils is just too new to get all of the behavior exactly the same. I've tested it on my nix machine in the past, and alothough I never pushed uutils quite as far as it could have gone in order to discover any of these bugs, I kind of shudder to think what would have happened if I had.

Very interesting to think that the concept of C isn't exactly bad-- but it just needs a long time to mature and get it right, just like any program. The fact that the Rust compiler prevents you from making memory errors doesn't also prevent you from misunderstanding CPU clocks or buffer overflows or race conditions and other low level stuff.

]]>https://forum.other.li/post/https://hachyderm.io/users/abmurrow/statuses/116518051024480413https://forum.other.li/post/https://hachyderm.io/users/abmurrow/statuses/116518051024480413Mon, 04 May 2026 19:52:42 GMT<![CDATA[Reply to The coreutils Rust rewrite story is pretty funny. on Mon, 04 May 2026 19:49:48 GMT]]>@lcamtuf yeah it's frustrating because in some sense we all had the opportunity to learn this lesson, a long time ago

we remember when we were kids, after Netscape went bankrupt trying to re-write their software from scratch, there were some good essays analyzing what went wrong and advocating for refactoring instead so as not to lose the knowledge that's in the code

and then there's the ATC system

like... there's so many past instances to learn from

]]>https://forum.other.li/post/https://adhd.irenes.space/users/ireneista/statuses/01KQT8MA1MC610Y46TSJSVW89Zhttps://forum.other.li/post/https://adhd.irenes.space/users/ireneista/statuses/01KQT8MA1MC610Y46TSJSVW89ZMon, 04 May 2026 19:49:48 GMT<![CDATA[Reply to The coreutils Rust rewrite story is pretty funny. on Mon, 04 May 2026 19:46:57 GMT]]>@lcamtuf I've heard a lot of funny stories like this in previous years. Like for example a startup trying to rewrite the TCP stack by their own from scratch because they can do it more efficient.
Soon they learned how a real environment, or better said, the real life really is.

]]>https://forum.other.li/post/https://gts.maverick-hq.org/users/z3r0/statuses/01KQT8F2YXJMH4BJE9KPFW7XDFhttps://forum.other.li/post/https://gts.maverick-hq.org/users/z3r0/statuses/01KQT8F2YXJMH4BJE9KPFW7XDFMon, 04 May 2026 19:46:57 GMT<![CDATA[Reply to The coreutils Rust rewrite story is pretty funny. on Mon, 04 May 2026 19:43:35 GMT]]>@lcamtuf@infosec.exchange Also quite few are noticeably fails in implementing POSIX, which makes me wonder if they're only caring about coreutils testsuite and --help/help2man output.

Like CVE-2026-35367 (nohup(1) permissions) as Colin Funk noted, but also CVE-2026-35369 (kill -1), CVE-2026-35370 & CVE-2026-35371 (real vs. effective in id(1)), and CVE-2026-35379 (wrong character classes in tr(1))

]]>https://forum.other.li/post/https://queer.hacktivis.me/objects/42e4da24-95b7-487c-8aea-b605ca2c86b7https://forum.other.li/post/https://queer.hacktivis.me/objects/42e4da24-95b7-487c-8aea-b605ca2c86b7Mon, 04 May 2026 19:43:35 GMT<![CDATA[Reply to The coreutils Rust rewrite story is pretty funny. on Mon, 04 May 2026 19:42:11 GMT]]>@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.

]]>https://forum.other.li/post/https://infosec.exchange/users/ryanc/statuses/116518009672810653https://forum.other.li/post/https://infosec.exchange/users/ryanc/statuses/116518009672810653Mon, 04 May 2026 19:42:11 GMT<![CDATA[Reply to The coreutils Rust rewrite story is pretty funny. on Mon, 04 May 2026 19:41:04 GMT]]>@david_chisnall @lcamtuf Well people have opinions: https://mastodon.social/@pid_eins/116459585811044061 😛

Btw also https://chaos.social/@tris/116453545444380978

]]>https://forum.other.li/post/https://chaos.social/users/tris/statuses/116518005263177974https://forum.other.li/post/https://chaos.social/users/tris/statuses/116518005263177974Mon, 04 May 2026 19:41:04 GMT<![CDATA[Reply to The coreutils Rust rewrite story is pretty funny. on Mon, 04 May 2026 19:40:51 GMT]]>@darkuncle tysm for pointing me to this amazing parable, amigos. ✌️💙

https://fs.blog/chestertons-fence/

]]>https://forum.other.li/post/https://hachyderm.io/users/nicksilkey/statuses/116518004443800907https://forum.other.li/post/https://hachyderm.io/users/nicksilkey/statuses/116518004443800907Mon, 04 May 2026 19:40:51 GMT<![CDATA[Reply to The coreutils Rust rewrite story is pretty funny. on Mon, 04 May 2026 19:38:37 GMT]]>@kajord @lcamtuf sure, it's Canonical's fault for deciding to deploy to production. And it's still a fault in the developers, for failing to understand why the original programs were written the way they were.

]]>https://forum.other.li/post/https://mastodon.social/users/hyc/statuses/116517995635054553https://forum.other.li/post/https://mastodon.social/users/hyc/statuses/116517995635054553Mon, 04 May 2026 19:38:37 GMT<![CDATA[Reply to The coreutils Rust rewrite story is pretty funny. on Mon, 04 May 2026 19:38:25 GMT]]>@miss_rodent @lcamtuf Right, there are some variances in command line options, usually in areas not covered by POSIX.

]]>https://forum.other.li/post/https://toad.social/users/grumpybozo/statuses/116517994830708114https://forum.other.li/post/https://toad.social/users/grumpybozo/statuses/116517994830708114Mon, 04 May 2026 19:38:25 GMT<![CDATA[Reply to The coreutils Rust rewrite story is pretty funny. on Mon, 04 May 2026 19:35:41 GMT]]>@grumpybozo @lcamtuf afaik the BSD core utils aren't entirely compatible with the gnu core utils, still?
But yeah, there are more permissively licensed versions of the *nix coreutils already; rust uutils is aiming to be a drop-in replacement for the gnu coreutils specifically, though, which means all the gnu-specific extensions and peculiarities. Which, previously, were basically only under the gpl (and some scripts and such can break if you don't have those, so, it's a meaningful difference.)

]]>https://forum.other.li/post/https://girlcock.club/users/miss_rodent/statuses/116517984091742764https://forum.other.li/post/https://girlcock.club/users/miss_rodent/statuses/116517984091742764Mon, 04 May 2026 19:35:41 GMT<![CDATA[Reply to The coreutils Rust rewrite story is pretty funny. on Mon, 04 May 2026 19:31:46 GMT]]>@hyc @lcamtuf this wasn't even storming in, this was a hobby project started in 2013 that was adopted for Ubuntu in 2025. I fault Canonical for that decision more than the project here.

]]>https://forum.other.li/post/https://hachyderm.io/users/kajord/statuses/116517968696177410https://forum.other.li/post/https://hachyderm.io/users/kajord/statuses/116517968696177410Mon, 04 May 2026 19:31:46 GMT<![CDATA[Reply to The coreutils Rust rewrite story is pretty funny. on Mon, 04 May 2026 19:23:44 GMT]]>@miss_rodent @lcamtuf If that was all they wanted, the BSD toolset is just sitting there….

]]>https://forum.other.li/post/https://toad.social/users/grumpybozo/statuses/116517937116844065https://forum.other.li/post/https://toad.social/users/grumpybozo/statuses/116517937116844065Mon, 04 May 2026 19:23:44 GMT<![CDATA[Reply to The coreutils Rust rewrite story is pretty funny. on Mon, 04 May 2026 19:23:34 GMT]]>@sten @darkuncle The old joke that _everyone_ has a testing environment, some are fortunate enough to have a separate Production environment 🙂

]]>https://forum.other.li/post/https://hachyderm.io/users/raven667/statuses/116517936489160553https://forum.other.li/post/https://hachyderm.io/users/raven667/statuses/116517936489160553Mon, 04 May 2026 19:23:34 GMT<![CDATA[Reply to The coreutils Rust rewrite story is pretty funny. on Mon, 04 May 2026 19:21:42 GMT]]>@lcamtuf It's even sillier because the Rust rewrite was just someones hobby project to learn Rust, it wasn't engineered from the start to be the "Canonical" implementation, so picking it off the Internet and shoving it into Ubuntu is an engineering decision that the professional Ubuntu engineers should be accountable for, not the original developer who just shared their work with the world.

]]>https://forum.other.li/post/https://hachyderm.io/users/raven667/statuses/116517929108918929https://forum.other.li/post/https://hachyderm.io/users/raven667/statuses/116517929108918929Mon, 04 May 2026 19:21:42 GMT<![CDATA[Reply to The coreutils Rust rewrite story is pretty funny. on Mon, 04 May 2026 19:21:09 GMT]]>@sten @lcamtuf sorry, it's been literally years since the last time I cared enough about this, so I don't have the links at hand. From what I remember, the dev(s) that got the project started claimed to not care about the license and that they would consider relicensing if the community showed an interest, but shot down all proposals to switch to GPL with no discussion.

Officially t's explicitly NOT about that:

https://uutils.github.io/

«It is not primarily […] about license debates.»

]]>https://forum.other.li/post/https://sociale.network/users/oblomov/statuses/116517926982676267https://forum.other.li/post/https://sociale.network/users/oblomov/statuses/116517926982676267Mon, 04 May 2026 19:21:09 GMT<![CDATA[Reply to The coreutils Rust rewrite story is pretty funny. on Mon, 04 May 2026 19:17:56 GMT]]>@star @hypha @lcamtuf yeah, the audits should have come first, not the other way around

all they did was give them free patches, so uh... yet another Rust advantage? ​

]]>https://forum.other.li/post/https://soc.masfloss.net/users/xerz/statuses/01KQT6SZ6A0H1930X6T5KQB04Chttps://forum.other.li/post/https://soc.masfloss.net/users/xerz/statuses/01KQT6SZ6A0H1930X6T5KQB04CMon, 04 May 2026 19:17:56 GMT<![CDATA[Reply to The coreutils Rust rewrite story is pretty funny. on Mon, 04 May 2026 19:13:10 GMT]]>@hypha @xerz @lcamtuf tbf i think the framing that "they shouldn't have" is wrong and bad. *canonical* should not have switched, because that is such a bad idea]]>https://forum.other.li/post/https://fed.amazonawaws.com/notes/alv55tf8nkhz2wqfhttps://forum.other.li/post/https://fed.amazonawaws.com/notes/alv55tf8nkhz2wqfMon, 04 May 2026 19:13:10 GMT