From f23e9116ebb71b63fe9cec0dcac792aa9af30b0c Mon Sep 17 00:00:00 2001
From: Denis Arefev <arefev@swemel.ru>
Date: Fri, 21 Mar 2025 13:52:31 +0300
Subject: [PATCH] drm/amd/pm: Prevent division by zero

The user can set any speed value.
If speed is greater than UINT_MAX/8, division by zero is possible.

Found by Linux Verification Center (linuxtesting.org) with SVACE.

Fixes: c05d1c401572 ("drm/amd/swsmu: add aldebaran smu13 ip support (v3)")
Signed-off-by: Denis Arefev <arefev@swemel.ru>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Cc: stable@vger.kernel.org
---
 drivers/gpu/drm/amd/pm/swsmu/smu13/smu_v13_0.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/amd/pm/swsmu/smu13/smu_v13_0.c b/drivers/gpu/drm/amd/pm/swsmu/smu13/smu_v13_0.c
index 0915d6377613..ba5a9012dbd5 100644
--- a/drivers/gpu/drm/amd/pm/swsmu/smu13/smu_v13_0.c
+++ b/drivers/gpu/drm/amd/pm/swsmu/smu13/smu_v13_0.c
@@ -1226,7 +1226,7 @@ int smu_v13_0_set_fan_speed_rpm(struct smu_context *smu,
 	uint32_t tach_period;
 	int ret;
 
-	if (!speed)
+	if (!speed || speed > UINT_MAX/8)
 		return -EINVAL;
 
 	ret = smu_v13_0_auto_fan_control(smu, 0);