Date:   Mon, 23 Jan 2023 22:30:30 -0500
From:   Gregory Price <gregory.price@memverge.com>
To:     Andrei Vagin <avagin@gmail.com>
Cc:     Gregory Price <gourry.memverge@gmail.com>,
        linux-kernel@vger.kernel.org, linux-fsdevel@vger.kernel.org,
        linux-doc@vger.kernel.org, linux-kselftest@vger.kernel.org,
        krisman@collabora.com, tglx@linutronix.de, luto@kernel.org,
        oleg@redhat.com, peterz@infradead.org, ebiederm@xmission.com,
        akpm@linux-foundation.org, adobriyan@gmail.com, corbet@lwn.net,
        shuah@kernel.org
Subject: Re: [PATCH 3/3] ptrace,syscall_user_dispatch: add a getter/setter
 for sud configuration
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On Mon, Jan 23, 2023 at 06:51:07PM -0800, Andrei Vagin wrote:
> On Sun, Jan 22, 2023 at 8:22 PM Gregory Price <gourry.memverge@gmail.com> wrote:
> <snip>
> >
> > +#define PTRACE_SET_SYSCALL_USER_DISPATCH_CONFIG 0x4210
> > +#define PTRACE_GET_SYSCALL_USER_DISPATCH_CONFIG 0x4211
> > +struct syscall_user_dispatch_config {
> > +       __u64 mode;
> > +       __s8 *selector;
> > +       __u64 offset;
> > +       __u64 len;
> > +       __u8 on_dispatch;
> 
> Sorry, I didn't notice this in the previous version. on_dispatch looks
> like an internal
> property and I don't see how we can stop a process with ptrace when on_dispatch
> is set to a non-zero value. I am not sure that we need to expose it to
> user-space.
> 
> Other than that, the patch looks good to me.
> 
> Thanks,
> Andrei

I tried tracing down the exit routes, but wasn't sure if there was a
no-return somewhere in the stack i hadn't accounted for, so i left it in
just in case.

I'll take one more look then i'll drop it before shipping out a v6.

May I add your Reviewed-by?

Thanks
~Gregory