Xz.git: Fix Linux Landlock Feature Test in Autotools
git.tukaani.orgThis is just spectacular. Evil, of course, but spectacular nevertheless.
+ #include <sys/prctl.h>
+. <<<<<<<<<<<<<<<<<<<<<<<< THIS IS IT
+ void my_sandbox(void)
+ {
+why bother with a . instead of a   or some other unicode hackdodgery?
A few reasons have been previously discussed: plenty of diff viewers highlight non-standard characters being a big one, the other bit being if someone does see this error it seems entirely plausible as a mistake.
Choosing something atypical in a way that is clearly trying to be invisible rather than being an accident will draw a lot more attention than “oops I must have typo’d it”
Thread from yesterday (221 comments): https://news.ycombinator.com/item?id=39874404
Can you spot the intentional bug in this commit?
It was checking if the C compiled to detect the landlock feature, and there was a single character in the middle of the code that made it always fail to compile and therefore silently leave the feature disabled.