Re: [PATCH] perf: Add NULL pointer check for cpu_map iteration and NULL assignment for all_cpus.

[Arnaldo Carvalho de Melo <acme@redhat.com>]

Em Wed, Mar 18, 2020 at 10:34:35AM -0300, Arnaldo Carvalho de Melo escreveu:
> Em Wed, Mar 18, 2020 at 11:32:24AM +0100, Jiri Olsa escreveu:
> > On Sun, Mar 08, 2020 at 06:59:17PM +0800, zhe.he@windriver.com wrote:
> > > From: He Zhe <zhe.he@windriver.com>
> > > 
> > > NULL pointer may be passed to perf_cpu_map__cpu and then cause crash,
> > > such as the one commit cb71f7d43ece ("libperf: Setup initial evlist::all_cpus value")
> > > fix.
> > > 
> > > Signed-off-by: He Zhe <zhe.he@windriver.com>
> > 
> > Acked-by: Jiri Olsa <jolsa@redhat.com>
> > 
> > thanks,
> > jirka
> > 
> > > ---
> > >  tools/perf/lib/cpumap.c | 2 +-
> > >  tools/perf/lib/evlist.c | 1 +
> > >  2 files changed, 2 insertions(+), 1 deletion(-)
> 
> this is in tools/lib/perf/ for some time already, I'll do the changes
> there, thanks,

Fixed up from tools/perf/lib to tools/lib/perf and applied.
 
> - Arnaldo
> 
> > > 
> > > diff --git a/tools/perf/lib/cpumap.c b/tools/perf/lib/cpumap.c
> > > index f93f4e7..ca02150 100644
> > > --- a/tools/perf/lib/cpumap.c
> > > +++ b/tools/perf/lib/cpumap.c
> > > @@ -247,7 +247,7 @@ struct perf_cpu_map *perf_cpu_map__new(const char *cpu_list)
> > >  
> > >  int perf_cpu_map__cpu(const struct perf_cpu_map *cpus, int idx)
> > >  {
> > > -	if (idx < cpus->nr)
> > > +	if (cpus && idx < cpus->nr)
> > >  		return cpus->map[idx];
> > >  
> > >  	return -1;
> > > diff --git a/tools/perf/lib/evlist.c b/tools/perf/lib/evlist.c
> > > index 5b9f2ca..f87a239 100644
> > > --- a/tools/perf/lib/evlist.c
> > > +++ b/tools/perf/lib/evlist.c
> > > @@ -127,6 +127,7 @@ void perf_evlist__exit(struct perf_evlist *evlist)
> > >  	perf_cpu_map__put(evlist->cpus);
> > >  	perf_thread_map__put(evlist->threads);
> > >  	evlist->cpus = NULL;
> > > +	evlist->all_cpus = NULL;
> > >  	evlist->threads = NULL;
> > >  	fdarray__exit(&evlist->pollfd);
> > >  }
> > > -- 
> > > 2.7.4
> > >