[Dle-develop] [BUGFIX PATCH -tip 3/5] perf probe: Fix event namelist to duplicate string

[Masami H. <mhi...@re...>]

Fix event namelist to duplicate string. Without duplicating,
adding multiple probes causes stack overwrite bug, because
it reuses a buffer on stack while the buffer is already
added in the namelist. String duplication solves this bug
because only contents of the buffer is copied to the namelist.

Signed-off-by: Masami Hiramatsu <mhi...@re...>
Cc: Ingo Molnar <mi...@el...>
Cc: Frederic Weisbecker <fwe...@gm...>
Cc: Arnaldo Carvalho de Melo <ac...@re...>
---

 tools/perf/util/probe-event.c |    4 +++-
 1 files changed, 3 insertions(+), 1 deletions(-)

diff --git a/tools/perf/util/probe-event.c b/tools/perf/util/probe-event.c
index cd7fbda..de0d913 100644
--- a/tools/perf/util/probe-event.c
+++ b/tools/perf/util/probe-event.c
@@ -413,12 +413,13 @@ static struct strlist *get_perf_event_names(int fd)
 
 	rawlist = get_trace_kprobe_event_rawlist(fd);
 
-	sl = strlist__new(false, NULL);
+	sl = strlist__new(true, NULL);
 	for (i = 0; i < strlist__nr_entries(rawlist); i++) {
 		ent = strlist__entry(rawlist, i);
 		parse_trace_kprobe_event(ent->s, &group, &event, NULL);
 		strlist__add(sl, event);
 		free(group);
+		free(event);
 	}
 
 	strlist__delete(rawlist);
@@ -480,5 +481,6 @@ void add_trace_kprobe_events(struct probe_point *probes, int nr_probes)
 			strlist__add(namelist, event);
 		}
 	}
+	strlist__delete(namelist);
 	close(fd);
 }


-- 
Masami Hiramatsu

Software Engineer
Hitachi Computer Products (America), Inc.
Software Solutions Division

e-mail: mhi...@re...