Date: Thu, 10 Nov 2016 16:40:46 -0800
From: Krister Johansen <kjlx@templeofstupid.com>
To: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>,
        Masami Hiramatsu <mhiramat@kernel.org>,
        =?utf-8?B?RnLDqWTDqXJpYw==?= Weisbecker <fweisbec@gmail.com>,
        linux-kernel@vger.kernel.org
Subject: Re: [PATCH v2 perf/core] perf script: fix a use after free crash.
Message-ID: <20161111004046.GA2185@templeofstupid.com>
References: <20161007022200.GB31113@sejong>
 <20161011092839.GC7837@templeofstupid.com>
 <20161026002010.GD2525@templeofstupid.com>
 <20161026134453.GA4936@kernel.org>
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On Wed, Oct 26, 2016 at 11:44:53AM -0200, Arnaldo Carvalho de Melo wrote:
> Em Tue, Oct 25, 2016 at 05:20:10PM -0700, Krister Johansen escreveu:
> > On Tue, Oct 11, 2016 at 02:28:39AM -0700, Krister Johansen wrote:
> > > If dso__load_kcore frees all of the existing maps, but one has already
> > > been attached to a callchain cursor node, then we can get a SIGSEGV in
> > > any function that happens to try to use this invalid cursor.  Use the
> > > existing map refcount mechanism to forestall cleanup of a map until the
> > > cursor iterates past the node.
> > 
> > It has been a couple of weeks since I sent out v2 of this patch.  I
> > understand that folks here have plenty of irons in the fire, but I
> > wanted to double-check that nobody was waiting on me for additional
> > information or changes.
> 
> It was a mix of waiting for more people to review it, or for Masami to
> run its refcount debugger on it, ended up falling thru the cracks.
> 
> I'll try to process it now.

Thanks.  As part of processing this did you run into any problems?
Would you like me to rebase against the latest perf/core and re-send the
patch?

-K