From d823685486a3446d061fed7c7d2f80af984f119a Mon Sep 17 00:00:00 2001
From: Wei Chen <harperchen1110@gmail.com>
Date: Wed, 15 Mar 2023 08:33:47 +0000
Subject: [PATCH] fbdev: intelfb: Fix potential divide by zero
Git-commit: d823685486a3446d061fed7c7d2f80af984f119a
Patch-mainline: v6.3-rc3
References: git-fixes
Variable var->pixclock is controlled by user and can be assigned
to zero. Without proper check, divide by zero would occur in
intelfbhw_validate_mode and intelfbhw_mode_to_hw.
Error out if var->pixclock is zero.
Signed-off-by: Wei Chen <harperchen1110@gmail.com>
Signed-off-by: Helge Deller <deller@gmx.de>
Acked-by: Takashi Iwai <tiwai@suse.de>
---
drivers/video/fbdev/intelfb/intelfbdrv.c | 3 +++
1 file changed, 3 insertions(+)
diff --git a/drivers/video/fbdev/intelfb/intelfbdrv.c b/drivers/video/fbdev/intelfb/intelfbdrv.c
index 0a9e5067b201..a81095b2b1ea 100644
--- a/drivers/video/fbdev/intelfb/intelfbdrv.c
+++ b/drivers/video/fbdev/intelfb/intelfbdrv.c
@@ -1222,6 +1222,9 @@ static int intelfb_check_var(struct fb_var_screeninfo *var,
dinfo = GET_DINFO(info);
+ if (!var->pixclock)
+ return -EINVAL;
+
/* update the pitch */
if (intelfbhw_validate_mode(dinfo, var) != 0)
return -EINVAL;
--
2.35.3