From: Zheyu Ma <zheyuma97@gmail.com>
To: deller@gmx.de
Cc: linux-fbdev@vger.kernel.org, Zheyu Ma <zheyuma97@gmail.com>,
linux-kernel@vger.kernel.org, dri-devel@lists.freedesktop.org
Subject: [PATCH 2/7] video: fbdev: neofb: Fix the check of 'var->pixclock'
Date: Mon, 4 Apr 2022 16:47:18 +0800 [thread overview]
Message-ID: <20220404084723.79089-3-zheyuma97@gmail.com> (raw)
In-Reply-To: <20220404084723.79089-1-zheyuma97@gmail.com>
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:
[ 49.704574] divide error: 0000 [#1] PREEMPT SMP KASAN PTI
[ 49.704593] RIP: 0010:neofb_set_par+0x190f/0x49a0
[ 49.704635] Call Trace:
[ 49.704636] <TASK>
[ 49.704650] fb_set_var+0x604/0xeb0
[ 49.704702] do_fb_ioctl+0x234/0x670
[ 49.704745] fb_ioctl+0xdd/0x130
[ 49.704753] do_syscall_64+0x3b/0x90
Signed-off-by: Zheyu Ma <zheyuma97@gmail.com>
---
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 966df2a07360..28d32cbf496b 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? */
--
2.25.1
next prev parent reply other threads:[~2022-04-04 8:47 UTC|newest]
Thread overview: 15+ messages / expand[flat|nested] mbox.gz Atom feed top
2022-04-04 8:47 [PATCH 0/7] Fix divide errors in fbdev drivers Zheyu Ma
2022-04-04 8:47 ` [PATCH 1/7] video: fbdev: i740fb: Error out if 'pixclock' equals zero Zheyu Ma
2022-04-07 19:49 ` Helge Deller
2022-04-08 1:58 ` Zheyu Ma
2022-04-10 9:02 ` Ondrej Zary
2022-04-11 6:18 ` Helge Deller
2022-04-04 8:47 ` Zheyu Ma [this message]
2022-04-04 8:47 ` [PATCH 3/7] video: fbdev: kyro: Error out if 'lineclock' " Zheyu Ma
2022-04-04 8:47 ` [PATCH 4/7] video: fbdev: vt8623fb: Error out if 'pixclock' " Zheyu Ma
2022-04-04 11:47 ` Geert Uytterhoeven
2022-04-04 8:47 ` [PATCH 5/7] video: fbdev: tridentfb: " Zheyu Ma
2022-04-04 8:47 ` [PATCH 6/7] video: fbdev: arkfb: " Zheyu Ma
2022-04-04 15:52 ` Geert Uytterhoeven
2022-04-04 8:47 ` [PATCH 7/7] video: fbdev: s3fb: " Zheyu Ma
2022-04-04 15:52 ` Geert Uytterhoeven
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