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Date:   Fri, 18 Mar 2022 20:43:37 +0100
From:   Oleg Nesterov <oleg@redhat.com>
To:     "Eric W. Biederman" <ebiederm@xmission.com>
Cc:     linux-kernel@vger.kernel.org,
        Linus Torvalds <torvalds@linux-foundation.org>,
        Alexey Gladkov <legion@kernel.org>,
        Kyle Huey <me@kylehuey.com>, Kees Cook <keescook@chromium.org>,
        Al Viro <viro@ZenIV.linux.org.uk>, linux-api@vger.kernel.org,
        Jens Axboe <axboe@kernel.dk>
Subject: Re: [PATCH 2/2] ptrace: Return the signal to continue with from
 ptrace_stop
Message-ID: <20220318194337.GA17638@redhat.com>
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On 03/17, Eric W. Biederman wrote:
>
> Oleg Nesterov <oleg@redhat.com> writes:
>
> > OK, I like it... but can't we remove the ugly "int clear_code" arg?
>
> The flag clear_code controls what happens if a ptrace_stop does not
> stop.  In particular clear_code means do not continue with
> a signal if we can not stop.
>
> For do_jobctl_trap calling ptrace_stop it clearly does not matter.
>
> For ptrace_signal it would be a change in behavior, that would
> cause the signal not to be delivered.

Well I meant that "clear_code" should be false, iirc only
ptrace_report_syscall() should be updated to void the spurious
send_sig() if debugger exits... Nevermind, pleasee forget, this is
not as trivial as I thought.

Acked-by: Oleg Nesterov <oleg@redhat.com>