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Date:   Wed, 22 Sep 2021 15:22:50 -0400
From:   Steven Rostedt <rostedt@goodmis.org>
To:     David Hildenbrand <david@redhat.com>
Cc:     Peter Collingbourne <pcc@google.com>,
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Subject: Re: [PATCH] kernel: introduce prctl(PR_LOG_UACCESS)
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        <29f1822d-e4cd-eedb-bea8-619db1d56335@redhat.com>
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On Wed, 22 Sep 2021 19:46:47 +0200
David Hildenbrand <david@redhat.com> wrote:

> > All signals except SIGKILL and SIGSTOP are masked for the interval
> > between the prctl() and the next syscall in order to prevent handlers
> > for intervening asynchronous signals from issuing syscalls that may
> > cause uaccesses from the wrong syscall to be logged.  
> 
> Stupid question: can this be exploited from user space to effectively 
> disable SIGKILL for a long time ... and do we care?

I first misread it too, but then caught my mistake reading it a second
time. It says "except SIGKILL". So no, it does not disable SIGKILL.

-- Steve