Re: [PATCH -next] scsi: aacraid: Use memdup_user() as a cleanup

[Samuel Zou]

Hi Martin,

Thanks for your review and reply.
You are right, it is not equivalent. I will keep the original goto 
cleanup. But the return value is changed to use of PTR_ERR 
(user_srbcmd), and assign it to rcode.
I will send the v2 soon later

On 2020/4/25 6:23, Martin K. Petersen wrote:
> Zou,
>
> > diff --git a/drivers/scsi/aacraid/commctrl.c b/drivers/scsi/aacraid/commctrl.c
> > index ffe41bc..1ce1620 100644
> > --- a/drivers/scsi/aacraid/commctrl.c
> > +++ b/drivers/scsi/aacraid/commctrl.c
> > @@ -513,17 +513,9 @@ static int aac_send_raw_srb(struct aac_dev* dev, void __user * arg)
> >   		goto cleanup;
> >   	}
> >   
> > -	user_srbcmd = kmalloc(fibsize, GFP_KERNEL);
> > -	if (!user_srbcmd) {
> > -		dprintk((KERN_DEBUG"aacraid: Could not make a copy of the srb\n"));
> > -		rcode = -ENOMEM;
> > -		goto cleanup;
> > -	}
> > -	if(copy_from_user(user_srbcmd, user_srb,fibsize)){
> > -		dprintk((KERN_DEBUG"aacraid: Could not copy srb from user\n"));
> > -		rcode = -EFAULT;
> > -		goto cleanup;
> > -	}
> > +	user_srbcmd = memdup_user(user_srb, fibsize);
> > +	if (IS_ERR(user_srbcmd))
> > +		return PTR_ERR(user_srbcmd);
> >   
> >   	flags = user_srbcmd->flags; /* from user in cpu order */
> >   	switch (flags & (SRB_DataIn | SRB_DataOut)) {
>
> This is not equivalent, is it? The original code does a goto cleanup;
> whereas your patch returns on error.