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Date:   Fri, 29 May 2020 10:00:04 +0200
From:   Christian Brauner <christian.brauner@ubuntu.com>
To:     Kees Cook <keescook@chromium.org>
Cc:     Robert Sesek <rsesek@google.com>, Chris Palmer <palmer@google.com>,
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Subject: Re: [PATCH v2 1/2] seccomp: notify user trap about unused filter
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On Fri, May 29, 2020 at 12:56:50AM -0700, Kees Cook wrote:
> On Fri, May 29, 2020 at 09:51:37AM +0200, Christian Brauner wrote:
> > Aside from this being not an issue now, can we please not dump seccomp
> > filter contents in proc. That sounds terrible and what's the rationale,
> > libseccomp already let's you dump filter contents while loading and you
> > could ptrace it. But maybe I'm missing a giant need for this...
> 
> The use-case comes from Android wanting to audit seccomp filters at
> runtime. I think this is stalled until there is a good answer to "what
> are you going to audit for, and how, given raw BPF?"

Doing this in proc seems very suboptimal why isn't this simply an
extension to the seccomp syscall (passing in a struct with the target's
pid or pidfd for example) to identify the target? But yeah, if there's
no real audit strategy all of that seems weird.

Christian