[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]
Date: Sun, 11 Nov 2018 13:19:45 +0300
From: Alexander Popov <alex.popov@...ux.com>
To: Steven Rostedt <rostedt@...dmis.org>
Cc: kernel-hardening@...ts.openwall.com, Kees Cook <keescook@...omium.org>,
Jann Horn <jannh@...gle.com>, Ingo Molnar <mingo@...nel.org>,
Andy Lutomirski <luto@...nel.org>, Joerg Roedel <joro@...tes.org>,
Borislav Petkov <bp@...en8.de>, Thomas Gleixner <tglx@...utronix.de>,
Dave Hansen <dave.hansen@...ux.intel.com>,
Peter Zijlstra <peterz@...radead.org>, Jan Kara <jack@...e.cz>,
Mathieu Desnoyers <mathieu.desnoyers@...icios.com>,
Dan Williams <dan.j.williams@...el.com>,
Masahiro Yamada <yamada.masahiro@...ionext.com>,
Masami Hiramatsu <mhiramat@...nel.org>, x86@...nel.org,
linux-kernel@...r.kernel.org
Subject: Re: [PATCH 1/1] stackleak: Disable ftrace for stackleak.c
On 11.11.2018 2:30, Steven Rostedt wrote:
> On Sun, 11 Nov 2018 01:05:30 +0300
> Alexander Popov <alex.popov@...ux.com> wrote:
>
>> The stackleak_erase() function is called on the trampoline stack at the
>> end of syscall. This stack is not big enough for ftrace operations,
>> e.g. it can be overflowed if we enable kprobe_events for stackleak_erase().
>
> Is the issue with kprobes or with function tracing? Because this stops
> function tracing which I only want disabled if function tracing itself
> is an issue, not for other things that may use the function tracing
> infrastructure.
Hello Steven,
I believe that stackleak erasing is not compatible with function tracing itself.
That's what the kernel testing robot has hit:
https://www.openwall.com/lists/kernel-hardening/2018/11/09/1
I used kprobe_events just to reproduce the problem:
https://www.openwall.com/lists/kernel-hardening/2018/11/09/4
Best regards,
Alexander
Powered by blists - more mailing lists
Confused about mailing lists and their use?
Read about mailing lists on Wikipedia
and check out these
guidelines on proper formatting of your messages.
