A Decade of Kill Bugs
Comments on “A Decade of Kill Bugs”
Claim-checked. Scored by all three judges, and its checkable claims were compared with the sources it cites. How far stories are checked
Alan Grow of Endcrawl traced an outage to /bin/kill in Ubuntu 24.04 LTS (procps 4.0.4). He says getopt's option bundling made kill -TERM -1490947 parse as pid -1, so root signaled everything except init. He ties this to earlier negative-pid bugs in Ubuntu 14, 16, 18 and 22; the version history and FreeBSD's clean record are unverified. His advice: put -- before process group IDs, kill with least privilege, and parse argv positionally. A fix for Ubuntu 24 is reportedly on its way.
Why it ranked
No. 14 of 107 with a score of 0.64. The panel rated it highest on new information (0.91) and technical depth (0.90), lowest on significance (0.49). Placed No. 14, No. 25 by score alone: the placement terms moved other stories past it.
- AI judgeJudge 2claude-haiku-5-5
- Detailed, well-substantiated postmortem of a real kill(1) bug history with code evidence; practically useful to systems builders, though niche and not a landmark development.
- AI judgeJudge 3gpt-5.6-luna
- A well-supported, technically detailed postmortem of recurring procps kill parsing bugs, with reproducible code-level explanations and concrete mitigations. It is highly useful to Unix/Linux operators and developers, though narrower than field-wide infrastructure news.
Each judge wrote its line after answering the rubric, with the site and the author still hidden. Every answer behind this is in the table under Score.
Score
0.64total under rubric v2.3
- Significance0.49
- Reader interest0.79
- Audience breadth0.53
- Practical relevance0.68
- Substantiated0.86
- Technical depth0.90
- New information0.91
- Counts against: Promotional0.03
- Counts against: Overclaim0.27
Each judge’s answer per question (0–1), their mean and spread, and what the question adds to the score (weight × mean).
| Question | Judge 1 | Judge 2 | Judge 3 | Mean | Spread | Weight | Contribution (weight times mean) |
|---|---|---|---|---|---|---|---|
| SignificanceHow much does this change what people in tech know or can do? | 0.52 | 0.35 | 0.62 | 0.49 | 0.27 | +0.24 | +0.119 |
| Reader interestWould a well-informed senior engineer or tech founder want to read this today, and likely pass it on? | 0.68 | 0.80 | 0.88 | 0.79 | 0.20 | +0.26 | +0.205 |
| Audience breadthHow many people who build technology does it concern? | 0.68 | 0.50 | 0.42 | 0.53 | 0.26 | +0.13 | +0.069 |
| Practical relevanceHow useful is it to someone who builds software or tech products? | 0.73 | 0.60 | 0.72 | 0.68 | 0.13 | +0.22 | +0.150 |
| SubstantiatedHow well is it backed? Consider whether it is the primary source, and whether its main claims come with data, code, a demo, a reproducible method or citations. | 0.86 | 0.85 | 0.86 | 0.86 | 0.01 | +0.05 | +0.043 |
| Technical depthHow technically substantive is it? | 1.00 | 0.85 | 0.86 | 0.90 | 0.15 | +0.05 | +0.045 |
| New informationDoes it contain information absent from the stories covered in the last 7 days (list provided)? | 0.90 | 0.85 | 0.97 | 0.91 | 0.12 | +0.05 | +0.045 |
| PromotionalIs it mainly marketing with little substance (a press release, ad or sponsored post with no real information)? A launch post that carries real news is not promotional. | 0.04 | 0.05 | 0.01 | 0.03 | 0.04 | −0.19 | −0.006 |
| OverclaimDo the headline or conclusions claim more than the body supports? | 0.27 | 0.25 | 0.30 | 0.27 | 0.05 | −0.11 | −0.030 |
| Sum of contributions | +0.640 | ||||||
| Claim-check penalty | 0.000 | ||||||
| Total, as published | 0.640 | ||||||
Spread is the highest minus the lowest judge answer. marks a spread above 0.40: the judges disagree, and the story is marked contested.
The badge for this ranking, for the author's page or anyone's: one line of HTML, and it links back here.
<a href="https://rubric.hrih.si/editions/2026-11-03/14/"><img src="https://rubric.hrih.si/badge/2026-11-03/14.svg" alt="Ranked #14 on Rubric, 3 Nov 2026" width="238" height="28"></a>Claim check
Claim check: 2 matches source · 2 no source given · 4 couldn’t check. Each claim is compared with the source the article itself cites; a flag is published only when both checkers agree.
Couldn’t checkCausal conclusion
The /bin/kill in Ubuntu 24.04 LTS comes from procps 4.0.4, whose option parsing misreads a multidigit negative pid like -1490947 as pid -1.
The source was unreachable, paywalled or too long, or the two checkers disagreed.
The article says “the misparsing of -1490947 as -1 killed every process but init”
The source says No passage could be compared.
Source cited by the article: gitlab.com/procps-ng/procps/-/releases/v4.0.4
Matches sourceQuote
Per the kill system call man page, a pid of -1 sends the signal to every process the caller has permission to signal, except process 1 (init).
The cited source says the same thing.
The article says “If pid equals -1, then sig is sent to every process for which the calling process has permission to send signals, except for process 1 (init”
The source says “If pid equals -1, then sig is sent to every process for which the calling process has permission to send signals, except for process 1 (init), but see below”
Source cited by the article: man7.org/linux/man-pages/man2/kill.2.html
Couldn’t checkDate
Killing a process group via negative pid became possible with Unix V9 in 1986.
The source was unreachable, paywalled or too long, or the two checkers disagreed.
The article says “It wasn't until Unix V9 in 1986 that you could kill a process group via negative pid”
The source says No passage could be compared.
Source cited by the article: tuhs.org/cgi-bin/utree.pl
No source givenNumber
Four distinct negative-pid bugs shipped in Ubuntu LTS releases (14, 16, 18, 22) over the last decade, with the same bug recurring in Ubuntu 24.
The article gives no link or citation for it.
The article says “There have been no less than FOUR distinct bugs around negative pids. And they all shipped in Ubuntu LTS versions”
The source says No source to compare with.
Couldn’t checkQuote
The POSIX spec says only argv[1] can specify the signal to send, and later arguments are pids and pgids.
The source was unreachable, paywalled or too long, or the two checkers disagreed.
The article says “The POSIX spec says that only argv[1] can specify the signal to send, and arguments beyond that are pids and pgids”
The source says No passage could be compared.
Source cited by the article: pubs.opengroup.org/onlinepubs/9699919799/utilities/kill.html
Couldn’t checkFirst, only or fastest
FreeBSD's kill parses argv positionally and has had no command line parsing bugs, unlike Linux's kill.
The source was unreachable, paywalled or too long, or the two checkers disagreed.
The article says “By contrast with Linux's kill, FreeBSD's kill has had no command line parsing bugs”
The source says No passage could be compared.
Source cited by the article: github.com/freebsd/freebsd-src/blob/bd4975e5fb051c2b2e8d5218940b7e8ef87b5bdf/bin/kill/kill.c
No source givenVersion
Ubuntu 14.04 LTS shipped procps 3.3.9, where kill -HUP -1 did nothing because getopt consumed the argument.
The article gives no link or citation for it.
The article says “Ubuntu 14.04 LTS included procps 3.3.9”
The source says No source to compare with.
Matches sourceDate
A bugfix for the Ubuntu 24 kill bug is already on its way at the time of publication.
The cited source says the same thing.
The article says “a bugfix for Ubuntu 24 is already on its way at the time of publication”
The source says “The attachment "Noble backport debdiff" seems to be a debdiff. The ubuntu-sponsors team has been subscribed to the bug report so that they can review and hopefully sponsor the debdiff”
Source cited by the article: lists.ubuntu.com/archives/ubuntu-sponsors/2026-September/088746.html
Also covered by
No other coverage was clustered with this story.
Elsewhere
Elsewhere: HN 3 pts, not on front page
Recorded for context only, checked 3 Nov 2026, 05:47 UTC. It played no part in the ranking.