add checks for lost samples and empty record in capabilities tracer

[matthyx]

add checks for lost samples and empty record in capabilities tracer

https://kubernetes.slack.com/archives/CSYL75LF6/p1704806538839969

How to use

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Testing done

[Describe the testing you have done before submitting this PR. Please include both the commands you issued as well as the output you got.]

[eiffel-fl]

Hi!

Thank you for the fix!
I will run the CI and test it locally in the meanwhile but everything looks fine from code inspection.
Can you please git blame and add a Fixes: tag to your commit message?

Best regards.

[matthyx]

@eiffel-fl what should I do with git blame?

[eiffel-fl]

@eiffel-fl what should I do with git blame?

Sorry, use git blame pkg/gadgets/trace/capabilities/tracer/tracer.go to find the original commit which added the file you modify.

[matthyx]

Sorry, use git blame pkg/gadgets/trace/capabilities/tracer/tracer.go to find the original commit which added the file you modify.

Ok will do right after my daily

[matthyx]

@eiffel-fl like that? I have added it to the line before Signed-off-by:

[eiffel-fl]

@eiffel-fl like that? I have added it to the line before Signed-off-by:

Normally, we also add the title of the commit within bracket, like:
e33ef85
But it will do the trick! Thank you for adding it!

I tested it locally and everything seems to be OK, sadly I cannot reproduce your bug:

$ sudo ./ig trace capabilities                               (remotes/matthyx/panic) %
RUNTIME.CONTAINERNAME                PID        COMM             SYSCALL               CAP CAPNAME            AUDIT               VERDICT
practical_dhawan                     18337      chown            fchownat              0   CHOWN              1                   Allow  
practical_dhawan                     18337      chown            fchownat              0   CHOWN              1                   Allow  
practical_dhawan                     18338      chmod            fchmodat              3   FOWNER             1                   Allow  
practical_dhawan                     18338      chmod            fchmodat              4   FSETID             1                   Allow 

Thinking more to this, maybe you can add a sentence in the commit message about your modification avoiding a panic?

[matthyx]

Thinking more to this, maybe you can add a sentence in the commit message about your modification avoiding a panic?

done

[eiffel-fl]

Thank you for the fix!