From mboxrd@z Thu Jan 1 00:00:00 1970 From: "Gustavo A. R. Silva" Subject: [PATCH] drm/rockchip: Use struct_size() in devm_kzalloc() Date: Sun, 26 Aug 2018 13:47:12 -0500 Message-ID: <20180826184712.GA9330@embeddedor.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: Content-Disposition: inline List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "Linux-rockchip" Errors-To: linux-rockchip-bounces+glpar-linux-rockchip=m.gmane.org-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r@public.gmane.org To: Sandy Huang , Heiko =?iso-8859-1?Q?St=FCbner?= , David Airlie Cc: Kees Cook , "Gustavo A. R. Silva" , linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, dri-devel-PD4FTy7X32lNgt0PjOBp9y5qC8QIuHrW@public.gmane.org, linux-rockchip-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r@public.gmane.org, linux-arm-kernel-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r@public.gmane.org List-Id: linux-rockchip.vger.kernel.org One of the more common cases of allocation size calculations is finding the size of a structure that has a zero-sized array at the end, along with memory for some number of elements for that array. For example: struct foo { int stuff; void *entry[]; }; instance = devm_kzalloc(dev, sizeof(struct foo) + sizeof(void *) * count, GFP_KERNEL); or, like in this particular case: size = sizeof(struct foo) + sizeof(void *) * count; instance = devm_kzalloc(dev, size, GFP_KERNEL); Instead of leaving these open-coded and prone to type mistakes, we can now use the new struct_size() helper: instance = devm_kzalloc(dev, struct_size(instance, entry, count), GFP_KERNEL); This issue was detected with the help of Coccinelle. Signed-off-by: Gustavo A. R. Silva --- drivers/gpu/drm/rockchip/rockchip_drm_vop.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) diff --git a/drivers/gpu/drm/rockchip/rockchip_drm_vop.c b/drivers/gpu/drm/rockchip/rockchip_drm_vop.c index 1359e5c..cf64e4d 100644 --- a/drivers/gpu/drm/rockchip/rockchip_drm_vop.c +++ b/drivers/gpu/drm/rockchip/rockchip_drm_vop.c @@ -32,6 +32,7 @@ #include #include #include +#include #include #include @@ -1561,7 +1562,6 @@ static int vop_bind(struct device *dev, struct device *master, void *data) struct drm_device *drm_dev = data; struct vop *vop; struct resource *res; - size_t alloc_size; int ret, irq; vop_data = of_device_get_match_data(dev); @@ -1569,8 +1569,8 @@ static int vop_bind(struct device *dev, struct device *master, void *data) return -ENODEV; /* Allocate vop struct and its vop_win array */ - alloc_size = sizeof(*vop) + sizeof(*vop->win) * vop_data->win_size; - vop = devm_kzalloc(dev, alloc_size, GFP_KERNEL); + vop = devm_kzalloc(dev, struct_size(vop, win, vop_data->win_size), + GFP_KERNEL); if (!vop) return -ENOMEM; -- 2.7.4