Re: [PATCH v2] tty: rfcomm: prefer struct_size over open coded arithmetic

Jiri Slaby
2024-05-13T05:07:35Z

On 12. 05. 24, 13:17, Erick Archer wrote:
> This is an effort to get rid of all multiplications from allocation
> functions in order to prevent integer overflows [1][2].
>
> As the "dl" variable is a pointer to "struct rfcomm_dev_list_req" and
> this structure ends in a flexible array:
...
> --- a/include/net/bluetooth/rfcomm.h
> +++ b/include/net/bluetooth/rfcomm.h
...
> @@ -528,12 +527,12 @@ static int rfcomm_get_dev_list(void __user *arg)
> list_for_each_entry(dev, &rfcomm_dev_list, list) {
> if (!tty_port_get(&dev->port))
> continue;
> - (di + n)->id = dev->id;
> - (di + n)->flags = dev->flags;
> - (di + n)->state = dev->dlc->state;
> - (di + n)->channel = dev->channel;
> - bacpy(&(di + n)->src, &dev->src);
> - bacpy(&(di + n)->dst, &dev->dst);
> + di[n].id = dev->id;
> + di[n].flags = dev->flags;
> + di[n].state = dev->dlc->state;
> + di[n].channel = dev->channel;
> + bacpy(&di[n].src, &dev->src);
> + bacpy(&di[n].dst, &dev->dst);

This does not relate much to "prefer struct_size over open coded
arithmetic". It should have been in a separate patch.

Other than that, LGTM.

thanks,
--
js
suse labs