From mboxrd@z Thu Jan 1 00:00:00 1970 From: "Gustavo A. R. Silva" Subject: [PATCH] drivers: qcom: rpmh: use struct_size() in kzalloc() Date: Thu, 23 Aug 2018 20:17:53 -0500 Message-ID: <20180824011753.GA25826@embeddedor.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Content-Disposition: inline Sender: linux-kernel-owner@vger.kernel.org To: Andy Gross , David Brown Cc: linux-arm-msm@vger.kernel.org, linux-soc@vger.kernel.org, linux-kernel@vger.kernel.org, Kees Cook , "Gustavo A. R. Silva" List-Id: linux-arm-msm@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 = kzalloc(sizeof(struct foo) + sizeof(void *) * count, GFP_ATOMIC); Instead of leaving these open-coded and prone to type mistakes, we can now use the new struct_size() helper: instance = kzalloc(struct_size(instance, entry, count), GFP_ATOMIC); This issue was detected with the help of Coccinelle. Signed-off-by: Gustavo A. R. Silva --- drivers/soc/qcom/rpmh.c | 3 +-- 1 file changed, 1 insertion(+), 2 deletions(-) diff --git a/drivers/soc/qcom/rpmh.c b/drivers/soc/qcom/rpmh.c index c7beb68..12c057a 100644 --- a/drivers/soc/qcom/rpmh.c +++ b/drivers/soc/qcom/rpmh.c @@ -362,8 +362,7 @@ int rpmh_write_batch(const struct device *dev, enum rpmh_state state, if (!count) return -EINVAL; - req = kzalloc(sizeof(*req) + count * sizeof(req->rpm_msgs[0]), - GFP_ATOMIC); + req = kzalloc(struct_size(req, rpm_msgs, count), GFP_ATOMIC); if (!req) return -ENOMEM; req->count = count; -- 2.7.4