From mboxrd@z Thu Jan 1 00:00:00 1970 From: Leon Romanovsky Subject: Re: [PATCH] RDMA/ucma: Use struct_size() helper Date: Wed, 5 Jun 2019 07:29:38 +0300 Message-ID: <20190605042938.GL5261@mtr-leonro.mtl.com> References: <20190604154222.GA8938@embeddedor> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Content-Disposition: inline In-Reply-To: <20190604154222.GA8938@embeddedor> Sender: linux-kernel-owner@vger.kernel.org To: "Gustavo A. R. Silva" Cc: Doug Ledford , Jason Gunthorpe , linux-rdma@vger.kernel.org, linux-kernel@vger.kernel.org List-Id: linux-rdma@vger.kernel.org On Tue, Jun 04, 2019 at 10:42:22AM -0500, Gustavo A. R. Silva wrote: > Make use of the struct_size() helper instead of an open-coded version > in order to avoid any potential type mistakes, in particular in the > context in which this code is being used. What does "in particular in the context in which this code is being used" mean? > > So, replace the following form: > > sizeof(*resp) + (i * sizeof(struct ib_path_rec_data)) > > with: > > struct_size(resp, path_data, i) It is already written inside commit itself. > > This code was detected with the help of Coccinelle. > > Signed-off-by: Gustavo A. R. Silva > --- > drivers/infiniband/core/ucma.c | 3 +-- > 1 file changed, 1 insertion(+), 2 deletions(-) > > diff --git a/drivers/infiniband/core/ucma.c b/drivers/infiniband/core/ucma.c > index 140a338a135f..cbe460076611 100644 > --- a/drivers/infiniband/core/ucma.c > +++ b/drivers/infiniband/core/ucma.c > @@ -951,8 +951,7 @@ static ssize_t ucma_query_path(struct ucma_context *ctx, > } > } > > - if (copy_to_user(response, resp, > - sizeof(*resp) + (i * sizeof(struct ib_path_rec_data)))) > + if (copy_to_user(response, resp, struct_size(resp, path_data, i))) > ret = -EFAULT; > > kfree(resp); > -- > 2.21.0 >