Re: [PATCH -next v2] staging: greybus: camera: Switch to memdup_user_nul()

[Yang Yingliang]

On 2021/4/1 15:47, Dan Carpenter wrote:
> On Thu, Apr 01, 2021 at 10:43:32AM +0300, Dan Carpenter wrote:
> > On Thu, Apr 01, 2021 at 11:17:52AM +0800, Yang Yingliang wrote:
> > > Use memdup_user_nul() helper instead of open-coding to
> > > simplify the code.
> > >
> > > Reported-by: Hulk Robot <hulkci@xxxxxxxxxx>
> > > Signed-off-by: Yang Yingliang <yangyingliang@xxxxxxxxxx>
> > > ---
> > >   drivers/staging/greybus/camera.c | 13 +++----------
> > >   1 file changed, 3 insertions(+), 10 deletions(-)
> > >
> > > diff --git a/drivers/staging/greybus/camera.c b/drivers/staging/greybus/camera.c
> > > index b570e13394ac..2ecdc1bc5092 100644
> > > --- a/drivers/staging/greybus/camera.c
> > > +++ b/drivers/staging/greybus/camera.c
> > > @@ -1120,16 +1120,9 @@ static ssize_t gb_camera_debugfs_write(struct file *file,
> > >   	if (len > 1024)
> > >   		return -EINVAL;
> > >   
> > > -	kbuf = kmalloc(len + 1, GFP_KERNEL);
> > > -	if (!kbuf)
> > > -		return -ENOMEM;
> > > -
> > > -	if (copy_from_user(kbuf, buf, len)) {
> > > -		ret = -EFAULT;
> > > -		goto done;
> > > -	}
> > > -
> > > -	kbuf[len] = '\0';
> > > +	kbuf = memdup_user_nul(buf, len);
> > > +	if (IS_ERR(kbuf))
> > > +		return PTR_ERR(kbuf);;
> >                                      ^^
> > There is an extra semi-colon here.  Checkpatch actually catches this
> > sort of typo.
> So when someone makes a typo like this, my response is:
>
> 1) Let's add this to checkpatch (turns out it was already done)
> 2) Let's grep the kernel and fix the other instances.  The command would
> be something like: git grep ';;$' | grep '\.c:'
I search it in kernel and find some other instances like this, I can 
send some
patches to fix these.

Thanks,
Yang
> regards,
> dan carpenter
>
> .