From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from gateway36.websitewelcome.com ([192.185.194.2]) by bombadil.infradead.org with esmtps (Exim 4.90_1 #2 (Red Hat Linux)) id 1ft0c7-0004Oh-Qx for linux-mtd@lists.infradead.org; Fri, 24 Aug 2018 01:10:13 +0000 Received: from cm16.websitewelcome.com (cm16.websitewelcome.com [100.42.49.19]) by gateway36.websitewelcome.com (Postfix) with ESMTP id 62BD1401B3221 for ; Thu, 23 Aug 2018 19:13:28 -0500 (CDT) Date: Thu, 23 Aug 2018 20:09:38 -0500 From: "Gustavo A. R. Silva" To: Josh Wu , Boris Brezillon , Miquel Raynal , Richard Weinberger , David Woodhouse , Brian Norris , Marek Vasut , Nicolas Ferre , Alexandre Belloni Cc: linux-mtd@lists.infradead.org, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, Kees Cook , "Gustavo A. R. Silva" Subject: [PATCH] mtd: rawnand: atmel: use struct_size() in devm_kzalloc() Message-ID: <20180824010938.GA25581@embeddedor.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline List-Id: Linux MTD discussion mailing list List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , 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); 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/mtd/nand/raw/atmel/nand-controller.c | 4 +--- 1 file changed, 1 insertion(+), 3 deletions(-) diff --git a/drivers/mtd/nand/raw/atmel/nand-controller.c b/drivers/mtd/nand/raw/atmel/nand-controller.c index a068b21..b17cfd0 100644 --- a/drivers/mtd/nand/raw/atmel/nand-controller.c +++ b/drivers/mtd/nand/raw/atmel/nand-controller.c @@ -1586,9 +1586,7 @@ static struct atmel_nand *atmel_nand_create(struct atmel_nand_controller *nc, return ERR_PTR(-EINVAL); } - nand = devm_kzalloc(nc->dev, - sizeof(*nand) + (numcs * sizeof(*nand->cs)), - GFP_KERNEL); + nand = devm_kzalloc(nc->dev, struct_size(nand, cs, numcs), GFP_KERNEL); if (!nand) { dev_err(nc->dev, "Failed to allocate NAND object\n"); return ERR_PTR(-ENOMEM); -- 2.7.4