Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753329AbbETP02 (ORCPT ); Wed, 20 May 2015 11:26:28 -0400 Received: from bombadil.infradead.org ([198.137.202.9]:38124 "EHLO bombadil.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754619AbbETP0W (ORCPT ); Wed, 20 May 2015 11:26:22 -0400 Date: Wed, 20 May 2015 17:26:07 +0200 From: Peter Zijlstra To: Vince Weaver Cc: Stephane Eranian , LKML , Arnaldo Carvalho de Melo , Jiri Olsa , Ingo Molnar , Paul Mackerras Subject: Re: perf: fuzzer triggers NULL pointer derefreence in x86_schedule_events Message-ID: <20150520152607.GK18673@twins.programming.kicks-ass.net> References: <20150501125955.GF5029@twins.programming.kicks-ass.net> <20150507124300.GK23123@twins.programming.kicks-ass.net> <20150520130312.GL3644@twins.programming.kicks-ass.net> <20150520134922.GH18673@twins.programming.kicks-ass.net> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20150520134922.GH18673@twins.programming.kicks-ass.net> User-Agent: Mutt/1.5.21 (2012-12-30) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1143 Lines: 36 On Wed, May 20, 2015 at 03:49:22PM +0200, Peter Zijlstra wrote: > --- > kernel/events/core.c | 5 ++++- > 1 file changed, 4 insertions(+), 1 deletion(-) > > diff --git a/kernel/events/core.c b/kernel/events/core.c > index 1a3bf48..a4f93fb 100644 > --- a/kernel/events/core.c > +++ b/kernel/events/core.c > @@ -7391,13 +7391,16 @@ static int perf_try_init_event(struct pmu *pmu, struct perf_event *event) > ctx = perf_event_ctx_lock_nested(event->group_leader, > SINGLE_DEPTH_NESTING); > BUG_ON(!ctx); > + raw_spin_lock_irq(&ctx->lock); > } > > event->pmu = pmu; > ret = pmu->event_init(event); > > - if (ctx) > + if (ctx) { > + raw_spin_unlock_irq(&ctx->lock); > perf_event_ctx_unlock(event->group_leader, ctx); > + } > > if (ret) > module_put(pmu->module); Except of course that ->event_init() likes to do an allocation :/ Needs to be fixed differently. -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/