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Date: Sun, 28 Jun 2026 12:11:19 -0700
From: Andrew Morton <akpm@linux-foundation.org>
To: Bradley Morgan <include@grrlz.net>
Cc: Oleg Nesterov <oleg@redhat.com>, Christian Brauner <brauner@kernel.org>,
 Steven Rostedt <rostedt@goodmis.org>, Masami Hiramatsu
 <mhiramat@kernel.org>, Mathieu Desnoyers <mathieu.desnoyers@efficios.com>,
 Peter Zijlstra <peterz@infradead.org>, Marco Elver <elver@google.com>,
 Aleksandr Nogikh <nogikh@google.com>, Thomas Gleixner <tglx@kernel.org>,
 Adrian Huang <adrianhuang0701@gmail.com>, Kexin Sun
 <kexinsun@smail.nju.edu.cn>, linux-kernel@vger.kernel.org,
 linux-trace-kernel@vger.kernel.org, stable@vger.kernel.org
Subject: Re: [PATCH v2 1/2] signal: avoid shared siginfo namespace rewrites
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On Mon, 22 Jun 2026 20:25:08 +0000 Bradley Morgan <include@grrlz.net> wrote:

> send_signal_locked() rewrites sender ids for the target namespace.
> Group sends reuse the same siginfo, so one recipient can affect the
> next.
> 
> Copy the siginfo before changing it.

Thanks, I'll queue this for 7.3-rc1.  I don't see a need to fast-track
it into mainline, as 7a0cf094944e is from 2019.

Can someone please send along a paragraph which describes the
userspace-visible effects of the bug?  I think this is important when
proposing a backportable fix.  Important for all fixes, really.

I understand that I'm to take no action with "[PATCH v2 2/2] signal:
make send_signal_locked() take const siginfo".