From 7c246a05df51c52fe0852ce56ba10c41e6ed1f39 Mon Sep 17 00:00:00 2001
From: Denis Arefev <arefev@swemel.ru>
Date: Fri, 21 Mar 2025 14:08:16 +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: c52dcf49195d ("drm/amd/pp: Avoid divide-by-zero in fan_ctrl_set_fan_speed_rpm")
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/powerplay/hwmgr/smu7_thermal.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/drivers/gpu/drm/amd/pm/powerplay/hwmgr/smu7_thermal.c b/drivers/gpu/drm/amd/pm/powerplay/hwmgr/smu7_thermal.c
index a8fc0fa44db69..ba5c1237fcfe1 100644
--- a/drivers/gpu/drm/amd/pm/powerplay/hwmgr/smu7_thermal.c
+++ b/drivers/gpu/drm/amd/pm/powerplay/hwmgr/smu7_thermal.c
@@ -267,10 +267,10 @@ int smu7_fan_ctrl_set_fan_speed_rpm(struct pp_hwmgr *hwmgr, uint32_t speed)
if (hwmgr->thermal_controller.fanInfo.bNoFan ||
(hwmgr->thermal_controller.fanInfo.
ucTachometerPulsesPerRevolution == 0) ||
- speed == 0 ||
+ (!speed || speed > UINT_MAX/8) ||
(speed < hwmgr->thermal_controller.fanInfo.ulMinRPM) ||
(speed > hwmgr->thermal_controller.fanInfo.ulMaxRPM))
- return 0;
+ return -EINVAL;
if (PP_CAP(PHM_PlatformCaps_MicrocodeFanControl))
smu7_fan_ctrl_stop_smc_fan_control(hwmgr);
--
GitLab