Re: [PATCH v2] drivers/iio: Remove all strcpy() uses in favor of strscpy()

From: Andy Shevchenko
Date: Tue Aug 10 2021 - 08:07:20 EST


On Mon, Aug 9, 2021 at 7:14 PM Len Baker <len.baker@xxxxxxx> wrote:
> On Mon, Aug 09, 2021 at 10:21:31AM +0100, Jonathan Cameron wrote:
> > On Sun, 8 Aug 2021 22:00:34 +0300
> > Andy Shevchenko <andy.shevchenko@xxxxxxxxx> wrote:
> > > On Sun, Aug 8, 2021 at 7:25 PM Jonathan Cameron <jic23@xxxxxxxxxx> wrote:
> > > > On Sat, 7 Aug 2021 17:22:25 +0200
> > > > Len Baker <len.baker@xxxxxxx> wrote:

...

> > > Isn't it too early? Or am I missing something (see below)?

> > > > > /* use length + 2 for adding minus sign if needed */
> > > > > - str = devm_kzalloc(regmap_get_device(st->map),
> > > > > - strlen(orient) + 2, GFP_KERNEL);
> > > > > + n = strlen(orient) + 2;
> > > > > + str = devm_kzalloc(regmap_get_device(st->map), n,
> > > > > + GFP_KERNEL);
> > > > > if (str == NULL)
> > > > > return -ENOMEM;
> > > > > if (strcmp(orient, "0") == 0) {
> > > > > - strcpy(str, orient);
> > > > > + strscpy(str, orient, n);
> > > > > } else if (orient[0] == '-') {
> > > > > - strcpy(str, &orient[1]);
> > > > > + strscpy(str, &orient[1], n);
> > > > > } else {
> > > > > str[0] = '-';
> > > > > - strcpy(&str[1], orient);
> > > > > + strscpy(&str[1], orient, n - 1);

Even if we leave the logic as is, this might be better

if (orient[0] == '-')
str = devm_kstrdup(dev, orient + 1, GFP_KERNEL);
else if (orient[0] != '0' || orient[1] != '\0')
str = devm_kasprintf(dev, GFP_KERNEL, "-%s", orient);
else
str = devm_kstrdup(dev, orient, GFP_KERNEL);
if (!str)
return -ENOMEM;

--
With Best Regards,
Andy Shevchenko