[PATCH 2/2] thermal/drivers/mediatek/lvts_thermal: Fix wrong lvts_ctrl index

[AngeloGioacchino Del Regno]

Il 03/05/24 17:35, Julien Panis ha scritto:
> In 'lvts_should_update_thresh()' and 'lvts_ctrl_start()' functions,
> the parameter passed to 'lvts_for_each_valid_sensor()' macro is always
> 'lvts_ctrl->lvts_data->lvts_ctrl'. In other words, the array index 0
> is systematically passed as 'struct lvts_ctrl_data' type item, even
> when another item should be consumed instead.
> 
> Hence, the 'valid_sensor_mask' value which is selected can be wrong
> because unrelated to the 'struct lvts_ctrl_data' type item that should
> be used. Hence, some thermal zone can be registered for a sensor 'i'
> that does not actually exist. Because of the invalid address used
> as 'lvts_sensor[i].msr', this situation ends up with a crash in
> 'lvts_get_temp()' function, where this 'msr' pointer is passed to
> 'readl_poll_timeout()' function. The following message is output:
> "Unable to handle kernel NULL pointer dereference at virtual
> address <msr>", with <msr> = 0.
> 
> This patch fixes the issue.
> 
> Fixes: 11e6f4c31447 ("thermal/drivers/mediatek/lvts_thermal: Allow early empty sensor slots")
> Signed-off-by: Julien Panis <jpanis at baylibre.com>

Reviewed-by: AngeloGioacchino Del Regno <angelogioacchino.delregno at collabora.com>