From: Gustavo A. R. Silva Date: Fri, 31 May 2019 19:24:53 +0000 (-0500) Subject: KVM: irqchip: Use struct_size() in kzalloc() X-Git-Url: http://git.lede-project.org./?a=commitdiff_plain;h=b3ffd74a2f6fbec131eff6d81bc7a6dbbac57bc7;p=openwrt%2Fstaging%2Fblogic.git KVM: irqchip: Use struct_size() in kzalloc() 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 = kzalloc(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 = kzalloc(struct_size(instance, entry, count), GFP_KERNEL); This code was detected with the help of Coccinelle. Signed-off-by: Gustavo A. R. Silva Signed-off-by: Paolo Bonzini --- diff --git a/virt/kvm/irqchip.c b/virt/kvm/irqchip.c index 79e59e4fa3dc..f8be6a3d1aa6 100644 --- a/virt/kvm/irqchip.c +++ b/virt/kvm/irqchip.c @@ -196,9 +196,7 @@ int kvm_set_irq_routing(struct kvm *kvm, nr_rt_entries += 1; - new = kzalloc(sizeof(*new) + (nr_rt_entries * sizeof(struct hlist_head)), - GFP_KERNEL_ACCOUNT); - + new = kzalloc(struct_size(new, map, nr_rt_entries), GFP_KERNEL_ACCOUNT); if (!new) return -ENOMEM;