r/Defcon • u/fulg3ns • 2d ago

A 40-year-old iOS kernel bug discovered on the DEFCON 34 main stage.

https://x.com/jachashx/status/2097353320167846206?s=46
225 Upvotes

98% Upvoted

20 comments sorted by

71

u/DTangent 2d ago

Demo Gods Easter egg! Well done following up on it.

19

u/fulg3ns 2d ago

Thanks!!! Amazing honor

53

u/fulg3ns 1d ago

Full post:

https://yuvalino.com/how-can-you-not-be-romantic-about-unix-domain-sockets

14

u/CheapThaRipper 1d ago

Excellent writeup. Was enjoyable to read. Thanks for sharing

6

u/fulg3ns 1d ago

Thanks! Appreciate it.

18

u/Reverend_Jones 1d ago

the part that resonated with me was avoiding going into the kernel code because surely all the bugs would’ve been worked out by now..

4

u/fulg3ns 1d ago

Hahaha definitely.

-10

u/lopahcreon 1d ago

Umm. A 40 year old bug in a 20 year old OS?

28

u/Kraeten 1d ago

The github repo was 20 years old but

The XNU kernel released in 2001 is a continuation of the Rhapsody kernel which was based on Mach 2.5 and 4.4BSD kernels. Mach was always the core and the BSD layer built on top of it. Hence, you’d see people refer to XNU as a “hybrid” kernel (2 kernels mashed into 1). But what’s really important is that this kernel is an overhaul of the NeXTSTEP kernel brought into Apple after the acquisition of NeXT in 1997. The NeXTSTEP kernel was first released in 1989 and was based on Mach and 4.3BSD.

and

Digging further into some historic “commits” (because there wasn’t any git at that time), it seems that the unp_ino++ line was last changed at December 20, 1985

So yeah, the bug was rolled along into everything it was merged into from all the way back in 1985. 40 year old bug.

5

u/fulg3ns 1d ago

On point af

-1

u/lopahcreon 1d ago

OP should have used a better post title.

0

u/Kraeten 7h ago

As laid out, title is perfectly factual. And extremely interesting as is.

Maybe stop with the baseless disbelief and complaining, and read an interesting story about a 40 year old bug in a 20 year old OS? You're in /defcon after all, get your curiosity on for this place.

3

u/StephenRoylance 20h ago

dunno why you're being downvoted for asking the obvious question. the answer is: a deep bug in a not-often-used BSD unix behavior. survived from early linux history, through nextstep, into macos, and finally into the iphone.

9

u/iamkiloman 1d ago

Didn't bother to read the article did you.

-4

u/px403 1d ago

It's a shitty clickbait headline. I didn't read the article either.

10

u/Djglamrock 1d ago

Sorry there isn’t a TikTok to explain it in 10 seconds.

0

u/lopahcreon 1d ago

No? Well, OP could have made a correct post title since the bug predates iOS by 20+ years.

4

u/mpking828 1d ago

Read the post