On Wed, May 31, 2023 at 12:38:26PM +0800, Su Hui wrote: > Use struct_size() instead of hand writing it. > This is less verbose and more informative. > > Signed-off-by: Su Hui <suhui@xxxxxxxxxxxx> > --- > drivers/gpu/drm/nouveau/nvif/object.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/drivers/gpu/drm/nouveau/nvif/object.c b/drivers/gpu/drm/nouveau/nvif/object.c > index 4d1aaee8fe15..4bd693aa4ee0 100644 > --- a/drivers/gpu/drm/nouveau/nvif/object.c > +++ b/drivers/gpu/drm/nouveau/nvif/object.c > @@ -65,7 +65,7 @@ nvif_object_sclass_get(struct nvif_object *object, struct nvif_sclass **psclass) > u32 size; > > while (1) { > - size = sizeof(*args) + cnt * sizeof(args->sclass.oclass[0]); > + size = struct_size(args, sclass.oclass, cnt); This is from the original code, but now that you are using the struct_size() macro static checkers will complain about it. (Maybe they don't yet?). size is a u32. Never save struct_size() returns to anything except unsigned long or size_t. (ssize_t is also fine, I suppose). Otherwise, you do not benefit from the integer overflow checking. > if (!(args = kmalloc(size, GFP_KERNEL))) > return -ENOMEM; > args->ioctl.version = 0; regards, dan carpenter