Re: [PATCH -tip ] [BUGFIX] perf probe: fix to initialize fname always before use it

[Arnaldo Carvalho de Melo <acme@ghostprotocols.net>]

Em Fri, Oct 11, 2013 at 09:31:47PM +0900, Masami Hiramatsu escreveu:
> Hi Arnaldo,
> 
> I've found a bug in my previous patch which was already picked
> in the perf/urgent branch. The buggy commit id is
> 
> e08cfd4bda7683cdbe6971c26cf23e2afdb1e7a8
> 
> And this is not related to the previous series of perf probe
> updates.

Ok, so it must go via perf/urgent or if that ends up not being anymore
possible, via stable, will try the perf/urgent path today,

- Arnaldo
 
> Thank you,
> 
> (2013/10/11 21:23), Masami Hiramatsu wrote:
> > Fix perf probe --list to initialize fname local var always before
> > use it. This may cause a SEGV if there is a probe which is in
> > the function body but not in any inline function.
> > 
> > Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
> > Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
> > Cc: Paul Mackerras <paulus@samba.org>
> > Cc: Ingo Molnar <mingo@redhat.com>
> > Cc: Arnaldo Carvalho de Melo <acme@ghostprotocols.net>
> > Cc: Namhyung Kim <namhyung@kernel.org>
> > ---
> >  tools/perf/util/probe-finder.c |    2 +-
> >  1 file changed, 1 insertion(+), 1 deletion(-)
> > 
> > diff --git a/tools/perf/util/probe-finder.c b/tools/perf/util/probe-finder.c
> > index c044052..e41b094 100644
> > --- a/tools/perf/util/probe-finder.c
> > +++ b/tools/perf/util/probe-finder.c
> > @@ -1460,10 +1460,10 @@ int debuginfo__find_probe_point(struct debuginfo *self, unsigned long addr,
> >  			goto post;
> >  		}
> >  
> > +		fname = dwarf_decl_file(&spdie);
> >  		if (addr == (unsigned long)baseaddr) {
> >  			/* Function entry - Relative line number is 0 */
> >  			lineno = baseline;
> > -			fname = dwarf_decl_file(&spdie);
> >  			goto post;
> >  		}
> 
> 
> -- 
> Masami HIRAMATSU
> IT Management Research Dept. Linux Technology Center
> Hitachi, Ltd., Yokohama Research Laboratory
> E-mail: masami.hiramatsu.pt@hitachi.com
>