From mboxrd@z Thu Jan 1 00:00:00 1970 From: "Gustavo A. R. Silva" Subject: Re: [PATCH] drivers: qcom: rpmh: use struct_size() in kzalloc() Date: Wed, 9 Jan 2019 11:38:13 -0600 Message-ID: References: <20181224062235.GA27815@embeddedor.com> Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <20181224062235.GA27815@embeddedor.com> Content-Language: en-US Sender: linux-kernel-owner@vger.kernel.org To: Andy Gross , David Brown Cc: linux-arm-msm@vger.kernel.org, linux-kernel@vger.kernel.org List-Id: linux-arm-msm@vger.kernel.org Hi, Friendly ping: Who can ack or review this patch, please? Thanks -- Gustavo On 12/24/18 12:22 AM, Gustavo A. R. Silva wrote: > 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_KERNEL); > > 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_KERNEL); > > 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 c7beb6841289..12c057a0b325 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; >