FAILED: patch "[PATCH] drm/amd/pm: Prevent division by zero" failed to apply to 5.4-stable tree

FAILED: patch "[PATCH] drm/amd/pm: Prevent division by zero" failed to apply to 5.4-stable tree

[gregkh]

The patch below does not apply to the 5.4-stable tree.
If someone wants it applied there, or to any other stable or longterm
tree, then please email the backport, including the original git commit
id to <stable@vger.kernel.org>.

To reproduce the conflict and resubmit, you may use the following commands:

git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-5.4.y
git checkout FETCH_HEAD
git cherry-pick -x 4e3d9508c056d7e0a56b58d5c81253e2a0d22b6c
# <resolve conflicts, build, test, etc.>
git commit -s
git send-email --to '<stable@vger.kernel.org>' --in-reply-to '2025042249-versus-think-8c6c@gregkh' --subject-prefix 'PATCH 5.4.y' HEAD^..

Possible dependencies:



thanks,

greg k-h

------------------ original commit in Linus's tree ------------------

From 4e3d9508c056d7e0a56b58d5c81253e2a0d22b6c Mon Sep 17 00:00:00 2001
From: Denis Arefev <arefev@swemel.ru>
Date: Fri, 21 Mar 2025 13:52:33 +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: 031db09017da ("drm/amd/powerplay/vega20: enable fan RPM and pwm settings V2")
Signed-off-by: Denis Arefev <arefev@swemel.ru>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Cc: stable@vger.kernel.org

diff --git a/drivers/gpu/drm/amd/pm/powerplay/hwmgr/vega20_thermal.c b/drivers/gpu/drm/amd/pm/powerplay/hwmgr/vega20_thermal.c
index a3331ffb2daf..1b1c88590156 100644
--- a/drivers/gpu/drm/amd/pm/powerplay/hwmgr/vega20_thermal.c
+++ b/drivers/gpu/drm/amd/pm/powerplay/hwmgr/vega20_thermal.c
@@ -191,7 +191,7 @@ int vega20_fan_ctrl_set_fan_speed_rpm(struct pp_hwmgr *hwmgr, uint32_t speed)
 	uint32_t tach_period, crystal_clock_freq;
 	int result = 0;
 
-	if (!speed)
+	if (!speed || speed > UINT_MAX/8)
 		return -EINVAL;
 
 	if (PP_CAP(PHM_PlatformCaps_MicrocodeFanControl)) {