Help with LANDLOCK_ACCESS_FS_EXECUTE

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Hi all,

I'm actually writing a test for LANDLOCK_ACCESS_FS_EXECUTE flag in LTP [1].
The test is really simple: it applies the EXECUTE landlock rule inside a 
folder and it verifies that a binary inside it can be executed.
A similar test applies the rule only to the specific binary and check 
again its execution.

But while I was writing the test, I encountered an issue with the 
specific rule setup, since EACCES is raised unexpectedly during binary 
execution.
So I wrote a reproducer, assuming that LTP might be the issue, but it's 
not. The reproducer actually shows that binary can't be executed after 
applying the EXECUTE rule.

I will attach the source code to this email. Can you please tell me if 
there's something wrong with it?

Best regards,
Andrea Cervesato


[1] https://linux-test-project.readthedocs.io/en/latest/

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