Hi Arnd, > Subject: Re: [PATCH 4/4] mic: vop: copy data to kernel space then write to io > memory > > On Fri, Sep 25, 2020 at 9:22 AM Sherry Sun <sherry....@nxp.com> wrote: > > > > > @@ -655,12 +656,15 @@ static int vop_virtio_copy_from_user(struct > vop_vdev *vdev, void __user *ubuf, > > * We are copying to IO below and should ideally use something > > * like copy_from_user_toio(..) if it existed. > > */ > > - if (copy_from_user((void __force *)dbuf, ubuf, len)) { > > + temp = kmalloc(len, GFP_KERNEL); > > + if (copy_from_user(temp, ubuf, len)) > > This needs to have error handling for a kmalloc() failure. As the length > appears to be user-provided, you might also want to limit the size of the > allocation and instead do a loop with multiple copies if there is more data > than fits into the allocation.
Thanks for your quick reply, you are right, will add error handling for kmalloc() failure and size limit handling in v2. Regards Sherry > > Arnd