From mboxrd@z Thu Jan 1 00:00:00 1970 From: "Gustavo A. R. Silva" Subject: [PATCH] i2c: mux: Use struct_size() in devm_kzalloc() Date: Wed, 29 May 2019 11:20:14 -0500 Message-ID: <20190529162014.GA27389@embeddedor> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Content-Disposition: inline Sender: linux-kernel-owner@vger.kernel.org To: Peter Rosin , Wolfram Sang Cc: linux-i2c@vger.kernel.org, linux-kernel@vger.kernel.org, "Gustavo A. R. Silva" List-Id: linux-i2c@vger.kernel.org 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; struct boo entry[]; }; instance = devm_kzalloc(dev, sizeof(struct foo) + count * sizeof(struct boo), 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 code was detected with the help of Coccinelle. Signed-off-by: Gustavo A. R. Silva --- drivers/i2c/i2c-mux.c | 3 +-- 1 file changed, 1 insertion(+), 2 deletions(-) diff --git a/drivers/i2c/i2c-mux.c b/drivers/i2c/i2c-mux.c index 603252fa1284..8d5e4c6fdd8e 100644 --- a/drivers/i2c/i2c-mux.c +++ b/drivers/i2c/i2c-mux.c @@ -243,8 +243,7 @@ struct i2c_mux_core *i2c_mux_alloc(struct i2c_adapter *parent, { struct i2c_mux_core *muxc; - muxc = devm_kzalloc(dev, sizeof(*muxc) - + max_adapters * sizeof(muxc->adapter[0]) + muxc = devm_kzalloc(dev, struct_size(muxc, adapter, max_adapters) + sizeof_priv, GFP_KERNEL); if (!muxc) return NULL; -- 2.21.0