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How a 20 year old bug in GTA San Andreas surfaced in Windows 11 24H2

(cookieplmonster.github.io)
1371 points yett | 1 comments | 23 Apr 25 14:00 UTC | HN request time: 1.156s | source
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adzm ◴[23 Apr 25 15:02 UTC] No.43773015[source]▶
I'm more curious in what changed with the critical section locking/unlocking implementation in this version of Windows!
replies(1): >>43773794 #
mjevans ◴[23 Apr 25 16:18 UTC] No.43773794[source]▶
It looks like the utilized stack, or a stack protection area, increased.
replies(1): >>43774040 #
asveikau ◴[23 Apr 25 16:48 UTC] No.43774040[source]▶
When I worked at Microsoft and I had downtime I would sometimes read the code for app compatibility shims out of pure curiosity.

Win9x video games that made bad assumptions about the stack were a theme I saw. One of the differences between win9x and NT based windows is that kernel32 (later kernelbase) is a now user mode wrapper atop ntdll, whereas in the olden days kernel32 would trap directly into the kernel. This means that kernel32 uses more user mode stack space in NT. A badly behaving app that stored data to the left of the stack pointer and called into kernel32 might see its data structures clobbered in NT and not in 9x. So there were compatibility hacks that temporarily moved the stack pointer for certain apps.

replies(2): >>43776559 #>>43778160 #
1. tom_ ◴[24 Apr 25 00:29 UTC] No.43778160[source]▶
I wonder how many people think of the call stack as running left to right, most recent return first, rather than top to bottom, likewise? If you stare at enough hex dumps, it makes perfect sense.