From: Steven Rostedt <rostedt@goodmis.org>
To: Wang Haoran <haoranwangsec@gmail.com>
Cc: Greg KH <gregkh@linuxfoundation.org>,
mhiramat@kernel.org, linux-kernel@vger.kernel.org,
linux-trace-kernel@vger.kernel.org,
mathieu.desnoyers@efficios.com, security@kernel.org
Subject: Re: [BUG] tracing: __copy_from_user without access_ok leaks kernel memory in syscall fault tracing
Date: Thu, 15 Oct 2026 09:42:09 -0400 [thread overview]
Message-ID: <20261015094209.7177cf03@gandalf.local.home> (raw)
In-Reply-To: <b2dd26de-efd0-4b8d-8086-ee5878a5703f@gmail.com>
On Thu, 15 Oct 2026 20:05:57 +0800
Wang Haoran <haoranwangsec@gmail.com> wrote:
Please send this to linux-trace-kernel@vger.kernel.org.
> From ca4e2a6928bbd9010ebec967440517b08909b992 Mon Sep 17 00:00:00 2001
> From: Haoran Wang <haoranwangsec@gmail.com>
> Date: Thu, 15 Oct 2026 19:12:21 +0800
> Subject: [PATCH] tracing/syscalls: use copy_from_user for the faultable
> syscall buffer
>
> Here is a working fix for the report. The leak is not strictly root
> only, so there is a security concern on systems that relax
> perf_event_paranoid.
Leave out any security details.
Simply state that the current check is missing the access_ok.
That is, this is a very trivial bug with a simple fix and a simple change
log. It could be a security concern for machines that trust perf a bit too
much.
But to go upstream, it still needs to follow the process.
Thanks,
-- Steve
prev parent reply other threads:[~2026-10-15 13:42 UTC|newest]
Thread overview: 4+ messages / expand[flat|nested] mbox.gz Atom feed top
2026-10-15 7:01 [BUG] tracing: __copy_from_user without access_ok leaks kernel memory in syscall fault tracing Haoran Wang
2026-10-15 8:44 ` Greg KH
2026-10-15 12:05 ` Wang Haoran
2026-10-15 13:42 ` Steven Rostedt [this message]
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