Re: [PATCH] PNP/ACPI: Fix string truncation warning

[Rafael J. Wysocki]

On Tue, Jul 25, 2023 at 7:29 AM Sunil V L <sunilvl@xxxxxxxxxxxxxxxx> wrote:
>
> LKP reports below warning when building for RISC-V.
>
> drivers/pnp/pnpacpi/core.c:253:17:
> warning: 'strncpy' specified bound 50 equals destination
> size [-Wstringop-truncation]
>
> This appears like a valid issue since the destination
> string may not be null-terminated. To fix this, append
> the NUL explicitly after the strncpy.
>
> Reported-by: kernel test robot <lkp@xxxxxxxxx>
> Closes: https://lore.kernel.org/oe-kbuild-all/202307241942.Rff2Nri5-lkp@xxxxxxxxx/
> Signed-off-by: Sunil V L <sunilvl@xxxxxxxxxxxxxxxx>
> ---
>  drivers/pnp/pnpacpi/core.c | 3 +++
>  1 file changed, 3 insertions(+)
>
> diff --git a/drivers/pnp/pnpacpi/core.c b/drivers/pnp/pnpacpi/core.c
> index 38928ff7472b..6ab272c84b7b 100644
> --- a/drivers/pnp/pnpacpi/core.c
> +++ b/drivers/pnp/pnpacpi/core.c
> @@ -254,6 +254,9 @@ static int __init pnpacpi_add_device(struct acpi_device *device)
>         else
>                 strncpy(dev->name, acpi_device_bid(device), sizeof(dev->name));
>
> +       /* Handle possible string truncation */
> +       dev->name[sizeof(dev->name) - 1] = '\0';
> +
>         if (dev->active)
>                 pnpacpi_parse_allocated_resource(dev);
>
> --

Applied as 6.6 material, thanks!