Re: [PATCH AUTOSEL 4.14 06/12] iio: core: Use min() instead of min_t() to make code more robust

From: Jonathan Cameron
Date: Sun Sep 10 2023 - 09:24:04 EST


On Fri, 8 Sep 2023 20:41:09 -0400
Sasha Levin <sashal@xxxxxxxxxx> wrote:

> From: Andy Shevchenko <andriy.shevchenko@xxxxxxxxxxxxxxx>
>
> [ Upstream commit cb1d17535061ca295903f97f5cb0af9db719c02c ]
>
> min() has strict type checking and preferred over min_t() for
> unsigned types to avoid overflow. Here it's unclear why min_t()
> was chosen since both variables are of the same type. In any
> case update to use min().
>
> Signed-off-by: Andy Shevchenko <andriy.shevchenko@xxxxxxxxxxxxxxx>
> Reviewed-by: Nuno Sa <nuno.sa@xxxxxxxxxx>
> Link: https://lore.kernel.org/r/20230721170022.3461-5-andriy.shevchenko@xxxxxxxxxxxxxxx
> Signed-off-by: Jonathan Cameron <Jonathan.Cameron@xxxxxxxxxx>
> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>

Whilst this was a good cleanup set from Andy, I don't think there was
any suggestion that it actually fixed any bugs?

As such I'd consider these (harmless) noise for stable.

Jonathan

> ---
> drivers/iio/industrialio-core.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/drivers/iio/industrialio-core.c b/drivers/iio/industrialio-core.c
> index 97b7266ee0ffa..12d73ebcadfa3 100644
> --- a/drivers/iio/industrialio-core.c
> +++ b/drivers/iio/industrialio-core.c
> @@ -328,7 +328,7 @@ static ssize_t iio_debugfs_write_reg(struct file *file,
> char buf[80];
> int ret;
>
> - count = min_t(size_t, count, (sizeof(buf)-1));
> + count = min(count, sizeof(buf) - 1);
> if (copy_from_user(buf, userbuf, count))
> return -EFAULT;
>