Re: [PATCH perf/core ] [BUGFIX] perf probe: Fix a segfault when removing uprobe events

[Arnaldo Carvalho de Melo <acme@kernel.org>]

Em Fri, Sep 18, 2015 at 01:39:13AM +0000, 平松雅巳 / HIRAMATU，MASAMI escreveu:
> Hi Arnaldo,
> 
> Could you pull this bugfix as an urgent patch, since this fixes a critical
> problem?

Sure, thanks for the reminder.

- Arnaldo
 
> Thanks,
> 
> From: Masami Hiramatsu [mailto:masami.hiramatsu.pt@hitachi.com]
> >
> >Fix a segfault bug and a small mistake in perf probe -d.
> >
> >Since the "ulist" in perf_del_probe_events is never initialized,
> >strlist__add(ulist, *) always causes a segfault when removing
> >uprobe events by perf probe -d.
> >
> >Also, the "str" local variable is never released if fail to
> >allocate the "klist". This fixes it too.
> >
> >This has been introduced by the commit e607f1426b58 ("perf probe:
> >Print deleted events in cmd_probe()").
> >
> >Reported-by: Milian Wolff <milian.wolff@kdab.com>
> >Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
> >---
> > tools/perf/builtin-probe.c |    7 +++++--
> > 1 file changed, 5 insertions(+), 2 deletions(-)
> >
> >diff --git a/tools/perf/builtin-probe.c b/tools/perf/builtin-probe.c
> >index 94385ee..f7882ae 100644
> >--- a/tools/perf/builtin-probe.c
> >+++ b/tools/perf/builtin-probe.c
> >@@ -380,8 +380,11 @@ static int perf_del_probe_events(struct strfilter *filter)
> > 		goto out;
> >
> > 	klist = strlist__new(NULL, NULL);
> >-	if (!klist)
> >-		return -ENOMEM;
> >+	ulist = strlist__new(NULL, NULL);
> >+	if (!klist || !ulist) {
> >+		ret = -ENOMEM;
> >+		goto out;
> >+	}
> >
> > 	ret = probe_file__get_events(kfd, filter, klist);
> > 	if (ret == 0) {
> >
>