From 85ec038b53faec11baefb2c42b6c0ce8bec94d3e Mon Sep 17 00:00:00 2001 From: Zheyu Ma Date: Mon, 4 Apr 2022 16:47:18 +0800 Subject: [PATCH] video: fbdev: neofb: Fix the check of 'var->pixclock' The previous check against 'var->pixclock' doesn't return -EINVAL when it equals zero, but the driver uses it again, causing the divide error. Fix this by returning when 'var->pixclock' is zero. The following log reveals it: divide error: 0000 [#1] PREEMPT SMP KASAN PTI RIP: 0010:neofb_set_par+0x190f/0x49a0 Call Trace: fb_set_var+0x604/0xeb0 do_fb_ioctl+0x234/0x670 fb_ioctl+0xdd/0x130 do_syscall_64+0x3b/0x90 Signed-off-by: Zheyu Ma Signed-off-by: Helge Deller --- drivers/video/fbdev/neofb.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/video/fbdev/neofb.c b/drivers/video/fbdev/neofb.c index 966df2a..28d32cb 100644 --- a/drivers/video/fbdev/neofb.c +++ b/drivers/video/fbdev/neofb.c @@ -585,7 +585,7 @@ neofb_check_var(struct fb_var_screeninfo *var, struct fb_info *info) DBG("neofb_check_var"); - if (var->pixclock && PICOS2KHZ(var->pixclock) > par->maxClock) + if (!var->pixclock || PICOS2KHZ(var->pixclock) > par->maxClock) return -EINVAL; /* Is the mode larger than the LCD panel? */ -- 2.7.4