perf probe: Release allocated probe_trace_event if failed

To fix a memory leak, release all allocated probe_trace_event on the
error path of try_to_find_probe_trace_events.

Reported-by: David Ahern <dsahern@gmail.com>
Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: "David A. Long" <dave.long@linaro.org>
Cc: "Steven Rostedt (Red Hat)" <rostedt@goodmis.org>
Cc: David Ahern <dsahern@gmail.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Cc: yrl.pp-manager.tt@hitachi.com
Link: http://lkml.kernel.org/r/20140116093944.24403.30228.stgit@kbuild-fedora.novalocal
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

tools/perf/util/probe-event.c

@@ -72,6 +72,7 @@ static int e_snprintf(char *str, size_t size, const char *format, ...)
 static char *synthesize_perf_probe_point(struct perf_probe_point *pp);
 static int convert_name_to_addr(struct perf_probe_event *pev,
 				const char *exec);
+static void clear_probe_trace_event(struct probe_trace_event *tev);
 static struct machine machine;
 
 /* Initialize symbol maps and path of vmlinux/modules */
@@ -407,6 +408,14 @@ static int add_module_to_probe_trace_events(struct probe_trace_event *tevs,
 	return ret;
 }
 
+static void clear_probe_trace_events(struct probe_trace_event *tevs, int ntevs)
+{
+	int i;
+
+	for (i = 0; i < ntevs; i++)
+		clear_probe_trace_event(tevs + i);
+}
+
 /* Try to find perf_probe_event with debuginfo */
 static int try_to_find_probe_trace_events(struct perf_probe_event *pev,
 					  struct probe_trace_event **tevs,
@@ -442,6 +451,10 @@ static int try_to_find_probe_trace_events(struct perf_probe_event *pev,
 				ret = add_module_to_probe_trace_events(*tevs,
 						 ntevs, target);
 		}
+		if (ret < 0) {
+			clear_probe_trace_events(*tevs, ntevs);
+			zfree(tevs);
+		}
 		return ret < 0 ? ret : ntevs;
 	}