From: Wei Chen <harperchen1110@gmail.com>
Date: Wed, 15 Mar 2023 09:05:18 +0000 (+0000)
Subject: fbdev: lxfb: Fix potential divide by zero
X-Git-Url: https://www.infradead.org/git/?a=commitdiff_plain;h=9f2a69d5e6770a064a7ae9bdab7e9907a8d292ff;p=users%2Fjedix%2Flinux-maple.git

fbdev: lxfb: Fix potential divide by zero

[ Upstream commit 61ac4b86a4c047c20d5cb423ddd87496f14d9868 ]

var->pixclock can be assigned to zero by user. Without proper
check, divide by zero would occur in lx_set_clock.

Error out if var->pixclock is zero.

Signed-off-by: Wei Chen <harperchen1110@gmail.com>
Signed-off-by: Helge Deller <deller@gmx.de>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---

diff --git a/drivers/video/fbdev/geode/lxfb_core.c b/drivers/video/fbdev/geode/lxfb_core.c
index 9d26592dbfce..41fda498406c 100644
--- a/drivers/video/fbdev/geode/lxfb_core.c
+++ b/drivers/video/fbdev/geode/lxfb_core.c
@@ -235,6 +235,9 @@ static void get_modedb(struct fb_videomode **modedb, unsigned int *size)
 
 static int lxfb_check_var(struct fb_var_screeninfo *var, struct fb_info *info)
 {
+	if (!var->pixclock)
+		return -EINVAL;
+
 	if (var->xres > 1920 || var->yres > 1440)
 		return -EINVAL;