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| author | Zheyu Ma <zheyuma97@gmail.com> | 2022-04-04 16:47:19 +0800 |
|---|---|---|
| committer | Helge Deller <deller@gmx.de> | 2022-04-11 08:23:49 +0200 |
| commit | 213e2df4733275165038d77289812d4473b0b010 (patch) | |
| tree | 1ed5a45d00f73105df698d6a7a5bba9abef9ee18 /drivers/video | |
| parent | 85ec038b53faec11baefb2c42b6c0ce8bec94d3e (diff) | |
| download | linux-213e2df4733275165038d77289812d4473b0b010.tar.bz2 | |
video: fbdev: kyro: Error out if 'lineclock' equals zero
The userspace program could pass any values to the driver through
ioctl() interface. If the driver doesn't check the value of 'lineclock',
it may cause divide error.
Fix this by checking whether 'lineclock' is zero.
The following log reveals it:
divide error: 0000 [#1] PREEMPT SMP KASAN PTI
RIP: 0010:kyrofb_set_par+0x30d/0xd80
Call Trace:
<TASK>
fb_set_var+0x604/0xeb0
do_fb_ioctl+0x234/0x670
fb_ioctl+0xdd/0x130
do_syscall_64+0x3b/0x90
Signed-off-by: Zheyu Ma <zheyuma97@gmail.com>
Signed-off-by: Helge Deller <deller@gmx.de>
Diffstat (limited to 'drivers/video')
| -rw-r--r-- | drivers/video/fbdev/kyro/fbdev.c | 2 |
1 files changed, 2 insertions, 0 deletions
diff --git a/drivers/video/fbdev/kyro/fbdev.c b/drivers/video/fbdev/kyro/fbdev.c index 25801e8e3f74..d57772f96ad2 100644 --- a/drivers/video/fbdev/kyro/fbdev.c +++ b/drivers/video/fbdev/kyro/fbdev.c @@ -494,6 +494,8 @@ static int kyrofb_set_par(struct fb_info *info) info->var.hsync_len + info->var.left_margin)) / 1000; + if (!lineclock) + return -EINVAL; /* time for a frame in ns (precision in 32bpp) */ frameclock = lineclock * (info->var.yres + |