Re: [PATCH v2] Input: tegra-kbc - check the pin numbers from the device tree

[Dmitry Torokhov <dmitry.torokhov@gmail.com>]

On Thu, Nov 05, 2026 at 10:13:03AM +0800, Guanglei Zhu wrote:
> The row and column pin lists are read straight from the device tree
> and used to index the pin configuration array:
> 
> 	for (i = 0; i < num_rows; i++) {
> 		kbc->pin_cfg[rows_cfg[i]].type = PIN_CFG_ROW;
> 		kbc->pin_cfg[rows_cfg[i]].num = i;
> 	}
> 
> The helper only limits how many entries it reads, not what they
> contain. Not all Tegra variants have KBC_MAX_GPIO pins - Tegra114,
> for example, has 11 rows + 8 columns = 19 - and the setup loop only
> initializes pin_cfg[] up to kbc->num_rows_and_columns, so a device
> tree that names a pin the variant does not have makes the row and
> column stores write over pin_cfg entries that were never touched,
> and the later check_pin_cfg() walk reads that stale data back as
> valid configuration.
> 
> Reject pin numbers the variant does not have.
> 
> Fixes: 88390243a993 ("Input: tegra-kbc - add support for rows/columns configuration from dt")
> Cc: stable@vger.kernel.org
> Signed-off-by: Guanglei Zhu <zhugl3@xiaopeng.com>

Applied, thank you (but dropped stable).

-- 
Dmitry