[PATCH AUTOSEL 5.15 7/8] ASoC: stm: Prevent potential division by zero in stm32_sai_get_clk_div()

[Sasha Levin <sashal@kernel.org>]

From: Luo Yifan <luoyifan@cmss.chinamobile.com>

[ Upstream commit 23569c8b314925bdb70dd1a7b63cfe6100868315 ]

This patch checks if div is less than or equal to zero (div <= 0). If
div is zero or negative, the function returns -EINVAL, ensuring the
division operation is safe to perform.

Signed-off-by: Luo Yifan <luoyifan@cmss.chinamobile.com>
Reviewed-by: Olivier Moysan <olivier.moysan@foss.st.com>
Link: https://patch.msgid.link/20241107015936.211902-1-luoyifan@cmss.chinamobile.com
Signed-off-by: Mark Brown <broonie@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 sound/soc/stm/stm32_sai_sub.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/sound/soc/stm/stm32_sai_sub.c b/sound/soc/stm/stm32_sai_sub.c
index aa9cdd93b5778..d71b4aecd269f 100644
--- a/sound/soc/stm/stm32_sai_sub.c
+++ b/sound/soc/stm/stm32_sai_sub.c
@@ -319,7 +319,7 @@ static int stm32_sai_get_clk_div(struct stm32_sai_sub_data *sai,
 	int div;
 
 	div = DIV_ROUND_CLOSEST(input_rate, output_rate);
-	if (div > SAI_XCR1_MCKDIV_MAX(version)) {
+	if (div > SAI_XCR1_MCKDIV_MAX(version) || div <= 0) {
 		dev_err(&sai->pdev->dev, "Divider %d out of range\n", div);
 		return -EINVAL;
 	}
-- 
2.43.0