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Comment by liveoneggs | Hacker News Reader

this is just a more complex version of the issue where go can't safely do the daemonize dance for a privileged port

There's a simple-ish workaround for the privileged port issue if you can't just use CAP_NET_ADMIN: http://play.golang.org/p/dXBizm4xl3

The namespace issues are unfortunately a lot tougher to address.

It's only reliable if none of your dependencies are spawning goroutines during initialization. If this is the case, some goroutines (yours' or the dependencies') can end up with increased privileges.

The workaround functions by opening the privileged socket and re-executing the binary as an unprivileged user with access to the filehandle. Any background goroutines would exit with the privileged parent.

Also: please don't spawn goroutines during init(). There's generally a better time and place, and in the event that you justifiably need a package-level background routine you can spawn it on demand with a sync.Once.

But you also want drop that privilege after using it to get the same effect as the "daemonize dance" GP referred to. And that's also per-thread, just like namespaces.

And that's unfortunately only an issue because Linux doesn't implement POSIX's model for thread privileges. In particular, glibc has to implement the nptl in userspace to make Linux threads look like POSIX threads.

I get the feeling that the Go runtime doesn't do the same.

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