From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from gateway34.websitewelcome.com ([192.185.148.214]) by bombadil.infradead.org with esmtps (Exim 4.90_1 #2 (Red Hat Linux)) id 1ggydQ-0004I9-Mz for linux-mtd@lists.infradead.org; Tue, 08 Jan 2019 21:10:06 +0000 Received: from cm11.websitewelcome.com (cm11.websitewelcome.com [100.42.49.5]) by gateway34.websitewelcome.com (Postfix) with ESMTP id F049195657E for ; Tue, 8 Jan 2019 15:09:48 -0600 (CST) Date: Tue, 8 Jan 2019 15:09:46 -0600 From: "Gustavo A. R. Silva" To: David Woodhouse , Brian Norris , Boris Brezillon , Marek Vasut , Richard Weinberger Cc: linux-mtd@lists.infradead.org, linux-kernel@vger.kernel.org, "Gustavo A. R. Silva" Subject: [PATCH] mtd: lpddr: Use struct_size() in kzalloc() Message-ID: <20190108210946.GA4014@embeddedor> 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 = 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 code was detected with the help of Coccinelle. Signed-off-by: Gustavo A. R. Silva --- drivers/mtd/lpddr/qinfo_probe.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/drivers/mtd/lpddr/qinfo_probe.c b/drivers/mtd/lpddr/qinfo_probe.c index 69f2112340b1..175bdc3b72f4 100644 --- a/drivers/mtd/lpddr/qinfo_probe.c +++ b/drivers/mtd/lpddr/qinfo_probe.c @@ -181,8 +181,8 @@ static struct lpddr_private *lpddr_probe_chip(struct map_info *map) lpddr.numchips = 1; numvirtchips = lpddr.numchips * lpddr.qinfo->HWPartsNum; - retlpddr = kzalloc(sizeof(struct lpddr_private) + - numvirtchips * sizeof(struct flchip), GFP_KERNEL); + retlpddr = kzalloc(struct_size(retlpddr, chips, numvirtchips), + GFP_KERNEL); if (!retlpddr) return NULL; -- 2.20.1