linux-kernel - Re: [PATCH v2] tracing: Protect the buffer from recursion in perf

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [day] [month] [year] [list]

Date:	Tue, 10 Nov 2009 11:40:04 +0100
From:	Frederic Weisbecker <fweisbec@...il.com>
To:	Peter Zijlstra <peterz@...radead.org>
Cc:	Ingo Molnar <mingo@...e.hu>, LKML <linux-kernel@...r.kernel.org>,
	Masami Hiramatsu <mhiramat@...hat.com>,
	Arnaldo Carvalho de Melo <acme@...hat.com>,
	Mike Galbraith <efault@....de>,
	Paul Mackerras <paulus@...ba.org>,
	Steven Rostedt <rostedt@...dmis.org>,
	Li Zefan <lizf@...fujitsu.com>, Jason Baron <jbaron@...hat.com>
Subject: Re: [PATCH v2] tracing: Protect the buffer from recursion in perf

On Tue, Nov 10, 2009 at 11:27:42AM +0100, Peter Zijlstra wrote:
> There already is recursion protection in
> kernel/perf_event.c:perf_swevent_recursion_context() and thereabouts.
> Could you not fix this by widening its scope?


Hmm, indeed.
I could probably use perf_swevent_recursion_context() directly from
the tracing fill path. And then split up a bit do_perf_sw_event()
so that it continues to check the recursion for normal software events
but not for trace events (for which we would already explicitly
call perf_swevent_recursion_context()).

I'll try that, thanks!

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/