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

commit 4b8c3c0d17c07f301011e2908fecd2ebdcfe3d1c 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 0c02fcbe4a1393a3c02da6ae35e72493cfdb2155)
Signed-off-by: Vijayendra Suman <[email protected]>

Author: Denis Arefev

drivers/gpu/drm/amd/pm/powerplay/hwmgr/vega10_thermal.c

@@ -307,10 +307,10 @@ int vega10_fan_ctrl_set_fan_speed_rpm(struct pp_hwmgr *hwmgr, uint32_t speed)
 	int result = 0;
 
 	if (hwmgr->thermal_controller.fanInfo.bNoFan ||
-	    speed == 0 ||
+	    (!speed || speed > UINT_MAX/8) ||
 	    (speed < hwmgr->thermal_controller.fanInfo.ulMinRPM) ||
 	    (speed > hwmgr->thermal_controller.fanInfo.ulMaxRPM))
-		return -1;
+		return -EINVAL;
 
 	if (PP_CAP(PHM_PlatformCaps_MicrocodeFanControl))
 		result = vega10_fan_ctrl_stop_smc_fan_control(hwmgr);