[PATCH 3.18 21/45] usb: chipidea: debug: check before accessing ci_role

[Greg Kroah-Hartman]

3.18-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Michael Thalmeier <michael.thalmeier@xxxxxxx>

commit 0340ff83cd4475261e7474033a381bc125b45244 upstream.

ci_role BUGs when the role is >= CI_ROLE_END.

Signed-off-by: Michael Thalmeier <michael.thalmeier@xxxxxxx>
Signed-off-by: Peter Chen <peter.chen@xxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

---
 drivers/usb/chipidea/debug.c |    3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

--- a/drivers/usb/chipidea/debug.c
+++ b/drivers/usb/chipidea/debug.c
@@ -290,7 +290,8 @@ static int ci_role_show(struct seq_file
 {
 	struct ci_hdrc *ci = s->private;
 
-	seq_printf(s, "%s\n", ci_role(ci)->name);
+	if (ci->role != CI_ROLE_END)
+		seq_printf(s, "%s\n", ci_role(ci)->name);
 
 	return 0;
 }