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@lcamtuf@infosec.exchange avatar lcamtuf , to random

So, you might have heard about > or ≥. But are you ready for...

≩ U+2269 GREATER-THAN BUT NOT EQUAL TO

⋛ U+22DB GREATER-THAN EQUAL TO OR LESS-THAN (just remember that ⋛ is not equal to ⋚)

⪌ U+2A8C GREATER-THAN ABOVE DOUBLE-LINE EQUAL ABOVE LESS-THAN (compare to ⪋, ⪒, and ⪑)

And of course, let's not forget the classic ⪔ U+2A94 GREATER-THAN ABOVE SLANTED EQUAL ABOVE LESS-THAN ABOVE SLANTED EQUAL (don't mix that one up with ⪓)

@lcamtuf@infosec.exchange avatar lcamtuf , to random

Did you know that Unicode has a symbol for "really equals, but this time I mean it"? It could come in handy for JavaScript

U+003D = EQUALS SIGN
U+2261 ≡ IDENTICAL TO
U+2263 ≣ STRICTLY EQUIVALENT TO

@lcamtuf@infosec.exchange avatar lcamtuf , to random
@lcamtuf@infosec.exchange avatar lcamtuf , to random

Math trivia: the "B." in Benoit B. Mandelbrot stands for Benoit B. Mandelbrot

@lcamtuf@infosec.exchange avatar lcamtuf , to random

Wow, impressive. You could be drinking water out of ordinary glass like a rube, or you could be infusing it with QUARTZ MOLECULES

@lcamtuf@infosec.exchange avatar lcamtuf , to random

Me: I want to have more friends

Tech companies:

@lcamtuf@infosec.exchange avatar lcamtuf , to random

My favorite fact about recycling is that 100% recycled plastic is often worthless, so instead, you add 5% of recycled material to a vat and make 10,000 shampoo bottles out of that, and then you take 500 of these bottles and label them "100% recycled".

Which is not wrong and yet terribly wrong at the same time

@lcamtuf@infosec.exchange avatar lcamtuf , to random

October is Cybersecurity Awareness Month! Please be aware of cybersecurity. If you encounter cybersecurity, DO NOT APPROACH IT. Back away slowly. Protect children and pets. Make noises to scare it away.

@lcamtuf@infosec.exchange avatar lcamtuf , to random

There are many claims that for some products, LLMs now write upward of 90% of the code.

No one publishes stats of the percentage of online articles that are written by LLMs, but I suspect the number is similar.

I'm nearly certain this is true for the average post that crops up on the internet.

For newspaper articles, I don't think it's 90%, but it's high. IIRC, I've seen obviously LLM-generated content on Newsweek, etc. And some of it isn't obvious.

HN front page: I'd wager it's one in ten.

lcamtuf OP ,
@lcamtuf@infosec.exchange avatar

@jerry Yeah, but I'd make a distinction between "hey ChatGPT, write an article about <x>" and "hey ChatGPT, can you make some style suggestions for what I've written".

Of course, there are some shades of gray in between.

@Daojoan@mastodon.social avatar Daojoan , to random

Social media gave everyone a printing press, then we discovered that most people use printing presses the same way they use bathroom stalls: to write inflammatory things they'd never say to someone's face...

lcamtuf ,
@lcamtuf@infosec.exchange avatar

@Daojoan I assumed this was going to be a pooping joke

@lcamtuf@infosec.exchange avatar lcamtuf , to random

The more embedded programming I do, the more amazed I am that anything works at all.

Even in a single-core, single-process bare-metal environment, you obviously get the standard range of reentrancy issues. Hardware interrupts - including nested interrupts - can fire at any time.

There are some big "huh" moments around stuff like DMA. If you request a DMA transfer, it's handled by a separate piece of silicon and your CPU doesn't necessarily know what transpired. The main memory is updated by the DMA controller, but the CPU's cache is not. The CPU might end up with a stale cache even if you haven't touched that memory region before: after all, it does speculative prefetching! Worse, if you did touch the region, the CPU may flush old pending writes after the DMA transfer, clobbering your data.

But sometimes, the problems are simpler. I had a program that ran at full clock speed when compiled with -O3, but at something like 1 MHz when not. Yep, "huh".

There was a function that allowed clock speed to be toggled for power save purposes, roughly this:

static void setup_clock(u8 fast) {
CCP = CCP_IOREG_gc; /* unlock */
CLKCTRL.OSCHFCTRLA = fast ? VAL1 : VAL2;
}

This was a two-step task: unlock clock operations by writing to a memory-mapped register called CCP, then manipulate OSCHFCTRLA to set clock speed. Easy enough.

Fine print not included in online examples: the sequence must take at most four CPU cycles. For reasons.

With -O3, the code was simply inlined, the parameter always being a compile-time constant. So, essentially just two insns.

Without -O3? Well, you had a conditional to calculate the value to write to OSCHFCTRLA based on the function parameter. Boom.

@lcamtuf@infosec.exchange avatar lcamtuf , to random

I see that a pretty but characteristically uninformative article about the Fourier transform is near the top of HN.

If you're interested in how DFT/DCT works, you might find my old write-up a better pick: https://lcamtuf.substack.com/p/not-so-fast-mr-fourier

@lcamtuf@infosec.exchange avatar lcamtuf , to random

I'm working on a universal bucket list for corporations:

  1. Declare that you're a different kind of a company

  2. Design and announce your own typeface

  3. One year of free credit monitoring

@lcamtuf@infosec.exchange avatar lcamtuf , to random

Life before smartphones

@lcamtuf@infosec.exchange avatar lcamtuf , to random

@bagder writes about his AI slop problem on H1: https://daniel.haxx.se/blog/2025/07/14/death-by-a-thousand-slops/

I like bug bounties and I put a fair amount of effort into bootstrapping the one at Google back in the day, but I think the problem runs deeper than AI.

First, most people who make a living doing bug bounties don't go after $10,000+ bugs. Very few researchers can crank out top-notch find month after month. A much better strategy on these platforms is to go after low-hanging fruit and rake in $500 to $1,000 bugs every day.

Companies respond accordingly! Because most of the traffic are low-value vulns from less skilled researchers, you don't want to throw your best analysts at this. It's increasingly common to outsource triage and bug-filing for bug bounty programs.

But if the person doing the triage isn't highly paid and familiar with the systems in question, there is a strong incentive to err on the side of caution. If you incorrectly close something serious as a non-issue, you risk the researcher making a stink. Conversely, if the triager files a non-issue with the product team, they'll probably fix it anyway, and the only cost is some wasted time.

The result is that in most programs, there's no penalty for slop. And researchers exploit this with spray-and-pray tactics. Why not?

I think one issue here are platforms that make it easy to window-browse for bug bounty programs. They have plenty of advantages, but it's a race to the bottom because the least diligent vendors set the bar for participation for all.

@lcamtuf@infosec.exchange avatar lcamtuf , to random

*** Online shopping in 2010 ***

Me: Hello, UnderpantsEmporium.com? I’d like to buy underpants.

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Me: Thanks.

*** Online shopping in 2025 ***

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ding ShipPirate.biz: Your package is getting shipped!

Me: Wait, who are yo…

phone vibrates SMS from 21525: ORDER UPDATE: package is on the move.

ding UPS MyChoice: Your package is on the way.

ding Underpants Emporium: Your pants-ckage is en route from us to you.

Me: dudes…

ding Underpants Emporium: Be sure to review your underpants!

ding UPS MyChoice: Your package is out for delivery. Follow it on a live map.

phone vibrates SMS from 21525: ORDER UPDATE: package is out for delivery.

phone vibrates SMS from +252 3983929301: There was a problem with your shipment. Please claim your package at che4p-pi1lz.virus-basket.biz.ru.

ding Underpants Emporium: how’s that review coming along?

phone vibrates SMS from 21525: ORDER UPDATE: the eagle has landed.

ding Underpants Emporium: customers who bought underpants also bought

@lcamtuf@infosec.exchange avatar lcamtuf , to random

Woodworkers are the most welcoming community I know of. You're talking to a master craftsman but they're still excited to see your garden planter.

On the flip side, the worst are probably electronics & math folks on Stack Exchange & Reddit: "get better before you talk to us".

Working theory: toxicity grows in proportion to the distance to wood

@lcamtuf@infosec.exchange avatar lcamtuf , to random

A slightly unhinged calculator fact: in the golden era of electronic calculators, some Japanese shopkeepers were reluctant to trust the newfangled tool, so Sharp made a line of combination calculator / abacus devices.

Here's a photo, next to some other stuff I own.

@lcamtuf@infosec.exchange avatar lcamtuf , to random

Computers use only two digits: zero and one. But now, with the discovery of five additional digits by a team of MIT researchers, this could change

@lcamtuf@infosec.exchange avatar lcamtuf , to random

How to tell that you're valued as a customer in 2025: if you need to wait 45 minutes to be connected to a representative, you know they're not using an LLM

@lcamtuf@infosec.exchange avatar lcamtuf , to random

Did you know?

@lcamtuf@infosec.exchange avatar lcamtuf , to random

What is even going on

image/png

@lcamtuf@infosec.exchange avatar lcamtuf , to random

So, if you're an old person, you probably remember the Crown Sterling "time AI" presentation at RSA. It happened six years ago and was the reason why people said "never again" to the conference before going there again and then getting upset about the next thing.

Anyway - I was putting some finishing touches on the article about complex numbers and came across this relevant paper (attached pics).

And while I don't want to dox the author, I did look up their bio and he "has focused on cryptography and data security. He founded Crown Sterling, a company that has developed innovative quantum-resistant encryption methods based on Quasi-Prime numbers"

Time is a flat cube

image/png

@lcamtuf@infosec.exchange avatar lcamtuf , to random

I'm old enough to remember when our #1 concern about the veracity of online information was that anyone could edit Wikipedia

@lcamtuf@infosec.exchange avatar lcamtuf , to random

For a long time, the largest jump in subscribers on my non-infosec Substack happened after I caved in and posted about the xz backdoor.

But that record has been shattered by this year's ultra-basic article on electricity: https://lcamtuf.substack.com/p/but-good-sir-what-is-electricity

So, I think we're officially a non-infosec publication, baby!

Makes me wonder - are there other relatively basic introductory articles that folks are interested in? I can write about math, chemistry, computers. I'm not the smartest person out there, but I have a keyboard and a blog

@lcamtuf@infosec.exchange avatar lcamtuf , to random
@lcamtuf@infosec.exchange avatar lcamtuf , to random

😍 HUGE THANKS TO ALL THE FANS! 🎉

🚀 Never in my wildest dreams did I expect to cross the important milestone of 1,000,000 subscribers! 🚀

and I must applaud myself for being 100% correct

@lcamtuf@infosec.exchange avatar lcamtuf , to random

Here's the thing. When a browser, an app, or a website encourages you to turn on an awesome feature, it's almost always because a lawyer who understands the feature said "whoa, we're gonna be in real trouble if we don't have consent".

In other words,

@lcamtuf@infosec.exchange avatar lcamtuf , to random

Yes, as a consumer, I wake up every day wishing that my electric toothbrush had more features

@lcamtuf@infosec.exchange avatar lcamtuf , to random

I must note that there is a certain irony in choosing a Mercedes

@lcamtuf@infosec.exchange avatar lcamtuf , to random

Look, "never" is relative

@lcamtuf@infosec.exchange avatar lcamtuf , to random

I think that Wikipedia is one of the best things that happened on the internet, but it isn't above criticism. Even if it's coming from your political enemies.

There are three issues at play. First, the Wikimedia Foundation. Their finances and activities are really hard to defend. They have too much money and they're spending it on sketchy stuff. The best argument for donating is that the excesses are OK if it keeps the server bills paid. But man...

The second issue is the Wikipedia editing culture. The editing standards work in >99% of all cases, but on some hot-button issues, the encyclopedia does have an editorial stance and weighs the sources to get the desired outcome. It's OK, but they need to own it. An editorial stance is not a crime.

The third issue is lone crackpots. In some niches, you have an editor with novel theories about UFOs, a beef with a minor celebrity, or a passion for Marxist apologetics. It sucks. The community could be doing better, but a big part of the problem is just that there aren't enough people watching and pushing back.

lcamtuf OP ,
@lcamtuf@infosec.exchange avatar

@molly0xfff @dave On the second point, to pick a timely example: consider "gravity is a thing" vs "the Gulf of Mexico should be still called the Gulf of Mexico".

In both cases, the usual Wikipedia response is that the encyclopedia has no opinion and is just reporting on the consensus. But the latter is an editorial policy decision, justified post-hoc by adding a section that defers to the all-important International Hydrographic Organization as the naming authority.

In contrast, Encyclopedia Britannica just posted a note saying "we're not renaming it because our audience wouldn't like it and we don't think the US has the authority". I think that's a better approach.

@lcamtuf@infosec.exchange avatar lcamtuf , to random

The thing about social media is that it's easy to get a lot of followers if you post enough memes, but the engagement is stretched so thin that it no longer means anything.

Here's my Twitter example: 37k followers → 2.5k "views" → 26 clicks (0.07%).

You get more out of mailing a couple of friends.

image/png

@lcamtuf@infosec.exchange avatar lcamtuf , to random

Your privacy is very important to us. This is why we're sharing your data with our 278 advertising partners, and our partners' 4,728 partners, and their partners' 87,392 partners, UNDER THE FOLLOWING TERMS

@lcamtuf@infosec.exchange avatar lcamtuf , to random

So I'm not a computer person, but it feels like there should be a way to design Mastodon so that if you post a link here, it doesn't get fetched SEVEN THOUSAND TIMES

@lcamtuf@infosec.exchange avatar lcamtuf , to random

C pro trick! Let's say you have code like this, and you want to comment out a block of code - let's say, lines 5 to 7 - with some nested comments. A pain, right?

lcamtuf OP ,
@lcamtuf@infosec.exchange avatar

Well, not anymore -- not with my patented POWER COMMENT technique!

https://godbolt.org/z/nEqhbhbse

@lcamtuf@infosec.exchange avatar lcamtuf , to random

Customer: I need a canary for my coal mine

Security product vendor: you've come to the right place, we have a wide selection of stuffed birds

@lcamtuf@infosec.exchange avatar lcamtuf , to random
@lcamtuf@infosec.exchange avatar lcamtuf , to random

The BASIC feature of the C language standard permits the use of familiar line numbering:

https://godbolt.org/z/dfsKGqYGz

You can use an if () statement to see if the feature is supported by your compiler.

@lcamtuf@infosec.exchange avatar lcamtuf , to random

I keep coming back to this, but hug your content creator today.

The internet has a bystander problem. We discover insightful content on the web, we assume the author already received the spoils - and we move on.

To offer a personal anecdote, I'm the author of afl-fuzz. It's been used by tens of thousands of folks - for hobby, for work, to elevate academic careers. I fielded hundreds of bug reports and feature requests - and perhaps two or three personal "thank you" notes.

Today, I'm running lcamtuf.substack.com. Some articles get 50k+ views. It works the same: there are far more folks keen to point out errors or post contrarian takes on HN.

I'm not fishing for compliments for myself. It's just that, the next time you come across a useful OSS project or an interesting blog, drop the author a note. No one else does.

@lcamtuf@infosec.exchange avatar lcamtuf , to random

Ah yes, I remember buying that textbook

@lcamtuf@infosec.exchange avatar lcamtuf , to random
@lcamtuf@infosec.exchange avatar lcamtuf , to random

Democracy dies in darkness

@lcamtuf@infosec.exchange avatar lcamtuf , to random

"Meta's Threads Now Has More Daily US Users Than Musk's X"

Users: "we did it, Patrick! We saved the city!"

You traded a smallish platform ran by an alt-right memelord for a platform operated by a privacy-hostile conglomerate that controls how 3.5 billion people get their news.

Whatever people think ails the internet, Facebook is far more to blame than Twitter ever was.

Twitter is and was a pretty niche platform, with DAU comparable to Quora and LinkedIn. It's just that a bunch of journos were really addicted to it.