KVM: irqchip: Use struct_size() in kzalloc()
PATCH 1/1 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.
--- virt/kvm/irqchip.c | 4 +--- 1 file changed, 1 insertion(+), 3 deletions(-)
virt/kvm/irqchip.c +1 -3
@@ -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 ;
Signature · 1 line
2.21.0
Quoted 29 lines · 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[]; };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 <[email protected]>--- virt/kvm/irqchip.c | 4 +--- 1 file changed, 1 insertion(+), 3 deletions(-)virt/kvm/irqchip.c +0
-0
virt/kvm/irqchip.c int kvm_set_irq_routing(struct kvm *kvm, · line 202
Quoted 10 lines
virt/kvm/irqchip.c +1
-3@@ -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 ;
Queued, thanks.
Paolo
Quoted 3 lines · Paolo Bonzini
Queued, thanks.
Great. :)
Thanks, Paolo.
--
Gustavo