From: Steven Rostedt <rostedt@goodmis.org>
To: Beau Belgrave <beaub@linux.microsoft.com>
Cc: XIAO WU <xiaowu.417@qq.com>,
Michael Bommarito <michael.bommarito@gmail.com>,
Masami Hiramatsu <mhiramat@kernel.org>,
Mathieu Desnoyers <mathieu.desnoyers@efficios.com>,
linux-trace-kernel@vger.kernel.org, linux-kernel@vger.kernel.org,
stable@vger.kernel.org
Subject: Re: [PATCH] tracing/user_events: fix use-after-free of enabler in user_event_mm_dup()
Date: Mon, 6 Jul 2026 16:06:50 -0400 [thread overview]
Message-ID: <20260706160650.2791767d@gandalf.local.home> (raw)
In-Reply-To: <20260624200535.GA132-beaub@linux.microsoft.com>
On Wed, 24 Jun 2026 20:05:35 +0000
Beau Belgrave <beaub@linux.microsoft.com> wrote:
> While I cannot repro this locally on my 16 core machine, I do agree this
> case needs to be handled correctly. The enabler should keep the ref to
> the user_event until after an RCU grace period. I have this fix that
> addresses it more completely than the original proposal.
>
> I'm hoping you can try out this fix with your machine that does repro
> the timing window. The below change needs self test fixes, since now the
> free happens after an RCU grace period + work queue schedule. This is
> because the self tests (abi_test and perf_test) assume after unreg the
> last ref is immediate (which was never guaranteed).
I'm taking in the OP patch, but this looks like a separate issue.
Any update on this?
-- Steve
next prev parent reply other threads:[~2026-07-06 20:06 UTC|newest]
Thread overview: 6+ messages / expand[flat|nested] mbox.gz Atom feed top
2026-06-18 22:27 [PATCH] tracing/user_events: fix use-after-free of enabler in user_event_mm_dup() Michael Bommarito
2026-06-19 0:12 ` Beau Belgrave
2026-06-22 17:03 ` XIAO WU
2026-06-24 20:05 ` Beau Belgrave
2026-07-06 20:06 ` Steven Rostedt [this message]
2026-07-06 20:11 ` Michael Bommarito
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