From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Date: Thu, 7 Feb 2019 18:58:56 -0600 From: "Gustavo A. R. Silva" Message-ID: <20190208005856.GA16642@embeddedor> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Subject: [Bridge] [PATCH net-next] bridge: use struct_size() helper List-Id: Linux Ethernet Bridging List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Roopa Prabhu , Nikolay Aleksandrov , "David S. Miller" Cc: netdev@vger.kernel.org, bridge@lists.linux-foundation.org, linux-kernel@vger.kernel.org, "Gustavo A. R. Silva" 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[]; }; size = sizeof(struct foo) + count * sizeof(struct boo); instance = alloc(size, GFP_KERNEL) Instead of leaving these open-coded and prone to type mistakes, we can now use the new struct_size() helper: size = struct_size(instance, entry, count); This code was detected with the help of Coccinelle. Signed-off-by: Gustavo A. R. Silva --- net/bridge/br_multicast.c | 3 +-- 1 file changed, 1 insertion(+), 2 deletions(-) diff --git a/net/bridge/br_multicast.c b/net/bridge/br_multicast.c index 1fb885a33c66..4a048fd1cbea 100644 --- a/net/bridge/br_multicast.c +++ b/net/bridge/br_multicast.c @@ -1018,8 +1018,7 @@ static int br_ip6_multicast_mld2_report(struct net_bridge *br, if (!nsrcs) return -EINVAL; - grec_len = sizeof(*grec) + - sizeof(struct in6_addr) * ntohs(*nsrcs); + grec_len = struct_size(grec, grec_src, ntohs(*nsrcs)); if (!ipv6_mc_may_pull(skb, len + grec_len)) return -EINVAL; -- 2.20.1