[PATCH v2 1/2] staging: greybus: audio: fix NULL dereference in gb_audio_manager_get_module()

[Hardik Phalet]

gb_audio_manager_get_module() calls gb_audio_manager_get_locked(), which
can return NULL when the requested id does not exist. The returned
pointer is dereferenced unconditionally via kobject_get(), leading to a
NULL pointer dereference.

Only take a kobject reference when the module is found.

Signed-off-by: Hardik Phalet <hardik.phalet@xxxxx>
---
 drivers/staging/greybus/audio_manager.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/drivers/staging/greybus/audio_manager.c b/drivers/staging/greybus/audio_manager.c
index 27ca5f796c5f..1da8804e61ca 100644
--- a/drivers/staging/greybus/audio_manager.c
+++ b/drivers/staging/greybus/audio_manager.c
@@ -111,7 +111,8 @@ struct gb_audio_manager_module *gb_audio_manager_get_module(int id)
 
 	down_read(&modules_rwsem);
 	module = gb_audio_manager_get_locked(id);
-	kobject_get(&module->kobj);
+	if (module)
+		kobject_get(&module->kobj);
 	up_read(&modules_rwsem);
 	return module;
 }
-- 
2.53.0