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From: Linus Torvalds <torvalds@linux-foundation.org>
Date: Sat, 2 Mar 2024 12:25:04 -0800
Message-ID: <CAHk-=wgyTTSw6yTaQ9-safdT8-MEpUWgFjqzHyeDrc8cZFui2g@mail.gmail.com>
Subject: Re: [GIT PULL] tracing: Prevent trace_marker being bigger than
 unsigned short
To: Steven Rostedt <rostedt@goodmis.org>
Cc: LKML <linux-kernel@vger.kernel.org>, Masami Hiramatsu <mhiramat@kernel.org>, 
	Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
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On Sat, 2 Mar 2024 at 12:00, Steven Rostedt <rostedt@goodmis.org> wrote:
>
> I don't have control over the strings. Anyone can do in user space:
>
>         fd = open("/sys/kernel/tracing/trace_marker", O_WRONLY);
>         r = write(fd, huge_string, 10000000);

So?

Stop the stupidity.

You already limit the string.

Just limit it to a sane value. if somebody uses a 10kB trace marker,
return an error, or just truncate it to 100 bytes.

You already were willing to truncate it to 32kB. Use your brain, and
realize that 32kB is a ridiculous limit.

Why do I even need to tell you this? I'm getting really tired of
having these idiotic arguments with you.

         Linus