From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, "Gustavo A. R. Silva" , Kees Cook , Avi Fishman , Stephen Boyd Subject: [PATCH 4.18 116/123] clk: npcm7xx: fix memory allocation Date: Mon, 3 Sep 2018 18:57:40 +0200 Message-Id: <20180903165724.404195950@linuxfoundation.org> In-Reply-To: <20180903165719.499675257@linuxfoundation.org> References: <20180903165719.499675257@linuxfoundation.org> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: 4.18-stable review patch. If anyone has any objections, please let me know. ------------------ From: Gustavo A. R. Silva commit 450b6b9b169382205f88858541a8b79830262ce7 upstream. 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); Notice that, currently, there is a bug during the allocation: sizeof(npcm7xx_clk_data) should be sizeof(*npcm7xx_clk_data) Fix this bug by using struct_size() in kzalloc() This issue was detected with the help of Coccinelle. Cc: stable@vger.kernel.org Signed-off-by: Gustavo A. R. Silva Reviewed-by: Kees Cook Reviewed-by: Avi Fishman Signed-off-by: Stephen Boyd Signed-off-by: Greg Kroah-Hartman --- drivers/clk/clk-npcm7xx.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) --- a/drivers/clk/clk-npcm7xx.c +++ b/drivers/clk/clk-npcm7xx.c @@ -558,8 +558,8 @@ static void __init npcm7xx_clk_init(stru if (!clk_base) goto npcm7xx_init_error; - npcm7xx_clk_data = kzalloc(sizeof(*npcm7xx_clk_data->hws) * - NPCM7XX_NUM_CLOCKS + sizeof(npcm7xx_clk_data), GFP_KERNEL); + npcm7xx_clk_data = kzalloc(struct_size(npcm7xx_clk_data, hws, + NPCM7XX_NUM_CLOCKS), GFP_KERNEL); if (!npcm7xx_clk_data) goto npcm7xx_init_np_err;