From d59bb703504a4e9324cda669368508dc72ffd485 Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Uwe=20Kleine-K=C3=B6nig?= Date: Fri, 21 Jun 2024 16:37:12 +0200 Subject: [PATCH] pwm: stm32: Refuse too small period requests MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit commit c45fcf46ca2368dafe7e5c513a711a6f0f974308 upstream. If period_ns is small, prd might well become 0. Catch that case because otherwise with regmap_write(priv->regmap, TIM_ARR, prd - 1); a few lines down quite a big period is configured. Fixes: 7edf7369205b ("pwm: Add driver for STM32 plaftorm") Cc: stable@vger.kernel.org Reviewed-by: Trevor Gamblin Signed-off-by: Uwe Kleine-König Link: https://lore.kernel.org/r/b86f62f099983646f97eeb6bfc0117bb2d0c340d.1718979150.git.u.kleine-koenig@baylibre.com Signed-off-by: Uwe Kleine-König Signed-off-by: Greg Kroah-Hartman --- drivers/pwm/pwm-stm32.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/drivers/pwm/pwm-stm32.c b/drivers/pwm/pwm-stm32.c index 359b08596d9e..4b20ff6f687b 100644 --- a/drivers/pwm/pwm-stm32.c +++ b/drivers/pwm/pwm-stm32.c @@ -337,6 +337,9 @@ static int stm32_pwm_config(struct stm32_pwm *priv, int ch, prd = div; + if (!prd) + return -EINVAL; + if (prescaler > MAX_TIM_PSC) return -EINVAL;