[PATCH 1/4] GPU-DRM-QXL: Use kmalloc_array() in qxl_device_init()

From: SF Markus Elfring
Date: Thu Sep 22 2016 - 02:20:38 EST


From: Markus Elfring <elfring@xxxxxxxxxxxxxxxxxxxxx>
Date: Wed, 21 Sep 2016 22:26:08 +0200

* A multiplication for the size determination of a memory allocation
indicated that an array data structure should be processed.
Thus use the corresponding function "kmalloc_array".

This issue was detected by using the Coccinelle software.

* Replace the specification of a data structure by a pointer dereference
to make the corresponding size determination a bit safer according to
the Linux coding style convention.

* Add a bit of exception handling for a detected null pointer.

Signed-off-by: Markus Elfring <elfring@xxxxxxxxxxxxxxxxxxxxx>
---
drivers/gpu/drm/qxl/qxl_kms.c | 9 +++++----
1 file changed, 5 insertions(+), 4 deletions(-)

diff --git a/drivers/gpu/drm/qxl/qxl_kms.c b/drivers/gpu/drm/qxl/qxl_kms.c
index e642242..76852f1 100644
--- a/drivers/gpu/drm/qxl/qxl_kms.c
+++ b/drivers/gpu/drm/qxl/qxl_kms.c
@@ -216,10 +216,11 @@ static int qxl_device_init(struct qxl_device *qdev,
qdev->slot_id_bits = qdev->rom->slot_id_bits;
qdev->va_slot_mask =
(~(uint64_t)0) >> (qdev->slot_id_bits + qdev->slot_gen_bits);
-
- qdev->mem_slots =
- kmalloc(qdev->n_mem_slots * sizeof(struct qxl_memslot),
- GFP_KERNEL);
+ qdev->mem_slots = kmalloc_array(qdev->n_mem_slots,
+ sizeof(*qdev->mem_slots),
+ GFP_KERNEL);
+ if (!qdev->mem_slots)
+ return -ENOMEM;

idr_init(&qdev->release_idr);
spin_lock_init(&qdev->release_idr_lock);
--
2.10.0