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Comment by saagarjha | Hacker News Reader

Neat! Although, I'm curious why the tool doesn't just run addr2line for you?

Are you asking why doesn't it execv(2) addr2line deep within the libc malloc implementation? Because calling execv(2) within libraries is frowned upon.. ;-)

The leak report is being generated internally by malloc. It is then logged via utrace(2) when a process is traced through ktrace(1).

The kdump utility simply dumps the report, strvis(3) escaping any potentially unsafe characters. As this is untrusted user data, passing it as the input/args to another command is unwise. Also kdump(1) uses pledge(2) and cannot execute commands.

Just link to the code instead of executing it as a separate binary

I'm pretty sure parsing ELF binaries is out of scope for kdump(1), sorry, but I don't think that's going to happen.

It's not that difficult to run addr2line yourself with the information provided, and that's really for the best.

You are arguing for a worse UX because of an arbitrary reason. Just link against the code in addr2line. Providing a good UX should always be in scope for a project.

How does one "just link against the code in addr2line" ?

You rename them main symbol to something else then you just call it like any other library.

addr2line is unlikely to be a trivial self-contained program without dependencies.

Then link to those dependencies.

Unnecessary. Most people's hands will be able to type up the required shell one-liner to do this.

Why would openbsd want to taint kdump with GPL code?

Then find or write an alternative. Asking people to run a command to see the file and line number is a joke.

LLVM provides llvm-addr2line and llvm-symbolizer. Of course I understand not wanting to link with LLVM code, even when the licence is ok. :)

I guess I’m confused what’s printing the output here. On other OSes typically things like this are implemented by malloc recording the addresses and whatever parses the report later doing the symbolication when displaying it. I guess kdump just dumps the report but is there no porcelain that takes the kdump data and cleans it up a bit more for human consumption?

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