[PATCH v3] staging: mmal-vchiq: add a check for the return of vmalloc()

[xkernel.wang at foxmail.com]

From: Xiaoke Wang <xkernel.wang at foxmail.com>

vmalloc() is a memory allocation API which can return NULL when some
internal memory errors happen. So it is better to check the return
value of it to catch the error in time.

Signed-off-by: Xiaoke Wang <xkernel.wang at foxmail.com>
---
ChangeLog:
v1->v2 jump to the proper location and remove redundant instruction.
v2->v3 fix the mistake bring by version 2.
 drivers/staging/vc04_services/vchiq-mmal/mmal-vchiq.c | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/drivers/staging/vc04_services/vchiq-mmal/mmal-vchiq.c b/drivers/staging/vc04_services/vchiq-mmal/mmal-vchiq.c
index 76d3f03..24cc0fe 100644
--- a/drivers/staging/vc04_services/vchiq-mmal/mmal-vchiq.c
+++ b/drivers/staging/vc04_services/vchiq-mmal/mmal-vchiq.c
@@ -1909,6 +1909,10 @@ int vchiq_mmal_init(struct vchiq_mmal_instance **out_instance)
 	mutex_init(&instance->vchiq_mutex);
 
 	instance->bulk_scratch = vmalloc(PAGE_SIZE);
+	if (!instance->bulk_scratch) {
+		err = -ENOMEM;
+		goto err_free_instance;
+	}
 	instance->vchiq_instance = vchiq_instance;
 
 	mutex_init(&instance->context_map_lock);
@@ -1940,6 +1944,7 @@ int vchiq_mmal_init(struct vchiq_mmal_instance **out_instance)
 	destroy_workqueue(instance->bulk_wq);
 err_free:
 	vfree(instance->bulk_scratch);
+err_free_instance:
 	kfree(instance);
 err_shutdown_vchiq:
 	vchiq_shutdown(vchiq_instance);
--