leds: qcom-lpg: Check for array overflow when selecting the high resolution

When selecting the high resolution values from the array, FIELD_GET() is
used to pull from a 3 bit register, yet the array being indexed has only
5 values in it.  Odds are the hardware is sane, but just to be safe,
properly check before just overflowing and reading random data and then
setting up chip values based on that.

Cc: stable <stable@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Link: https://patch.msgid.link/2026021934-nearby-playroom-036b@gregkh
Signed-off-by: Lee Jones <lee@kernel.org>

Author: gregkh

drivers/leds/rgb/leds-qcom-lpg.c

@@ -1273,7 +1273,12 @@ static int lpg_pwm_get_state(struct pwm_chip *chip, struct pwm_device *pwm,
 		return ret;
 
 	if (chan->subtype == LPG_SUBTYPE_HI_RES_PWM) {
-		refclk = lpg_clk_rates_hi_res[FIELD_GET(PWM_CLK_SELECT_HI_RES_MASK, val)];
+		unsigned int clk_idx = FIELD_GET(PWM_CLK_SELECT_HI_RES_MASK, val);
+
+		if (clk_idx >= ARRAY_SIZE(lpg_clk_rates_hi_res))
+			return -EINVAL;
+
+		refclk = lpg_clk_rates_hi_res[clk_idx];
 		resolution = lpg_pwm_resolution_hi_res[FIELD_GET(PWM_SIZE_HI_RES_MASK, val)];
 	} else {
 		refclk = lpg_clk_rates[FIELD_GET(PWM_CLK_SELECT_MASK, val)];