drm/amd/pm/powerplay/hwmgr/smu7_thermal: Prevent division by zero

commit 7c246a05df51c52fe0852ce56ba10c41e6ed1f39 upstream.

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: c52dcf4 ("drm/amd/pp: Avoid divide-by-zero in fan_ctrl_set_fan_speed_rpm")
Signed-off-by: Denis Arefev <[email protected]>
Signed-off-by: Alex Deucher <[email protected]>
Cc: [email protected]
Signed-off-by: Greg Kroah-Hartman <[email protected]>
(cherry picked from commit be0fffc4152aac4f0291ed2d793f3cfee788449d)
Signed-off-by: Vijayendra Suman <[email protected]>

Author: Denis Arefev

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);