[PATCH] fbdev: au1200fb: Fix potential divide by zero

From: Wei Chen
Date: Wed Mar 15 2023 - 05:23:16 EST


var->pixclock can be assigned to zero by user. Without
proper check, divide by zero would occur when invoking
macro PICOS2KHZ in au1200fb_fb_check_var.

Error out if var->pixclock is zero.

Signed-off-by: Wei Chen <harperchen1110@xxxxxxxxx>
---
drivers/video/fbdev/au1200fb.c | 3 +++
1 file changed, 3 insertions(+)

diff --git a/drivers/video/fbdev/au1200fb.c b/drivers/video/fbdev/au1200fb.c
index 81c315454428..b6b22fa4a8a0 100644
--- a/drivers/video/fbdev/au1200fb.c
+++ b/drivers/video/fbdev/au1200fb.c
@@ -1040,6 +1040,9 @@ static int au1200fb_fb_check_var(struct fb_var_screeninfo *var,
u32 pixclock;
int screen_size, plane;

+ if (!var->pixclock)
+ return -EINVAL;
+
plane = fbdev->plane;

/* Make sure that the mode respect all LCD controller and
--
2.25.1