perf probe: Fix coredump introduced by probe module option

perf will coredump if the user doesn't give the "-m" option in probe
command, this patch fixes it.

[root@localhost perf]# ./perf probe --add='PROBE'
Segmentation fault (core dumped)

Cc: Ingo Molnar <mingo@elte.hu>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1311602888-2389-1-git-send-email-bookjovi@gmail.com
Signed-off-by: Jovi Zhang <bookjovi@gmail.com>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

diff --git a/tools/perf/util/probe-event.c b/tools/perf/util/probe-event.c
index b82d54f..1c7bfa5 100644 (file)
--- a/tools/perf/util/probe-event.c
+++ b/tools/perf/util/probe-event.c
@@ -1820,11 +1820,15 @@ static int convert_to_probe_trace_events(struct perf_probe_event *pev,
                ret = -ENOMEM;
                goto error;
        }
-       tev->point.module = strdup(module);
-       if (tev->point.module == NULL) {
-               ret = -ENOMEM;
-               goto error;
+
+       if (module) {
+               tev->point.module = strdup(module);
+               if (tev->point.module == NULL) {
+                       ret = -ENOMEM;
+                       goto error;
+               }
        }
+
        tev->point.offset = pev->point.offset;
        tev->point.retprobe = pev->point.retprobe;
        tev->nargs = pev->nargs;