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| author | Zheyu Ma <zheyuma97@gmail.com> | 2022-04-04 11:47:22 +0300 |
|---|---|---|
| committer | Helge Deller <deller@gmx.de> | 2022-04-11 09:23:50 +0300 |
| commit | e1e965156438a3662dbb151d892ada834214c833 (patch) | |
| tree | ed045c858289dc74685f48bb6db01cef197b2875 /drivers/video | |
| parent | 16844e5870424c2728486dc0c0300ebf7fa09ad6 (diff) | |
| download | linux-e1e965156438a3662dbb151d892ada834214c833.tar.xz | |
video: fbdev: arkfb: Error out if 'pixclock' equals zero
The userspace program could pass any values to the driver through
ioctl() interface. If the driver doesn't check the value of 'pixclock',
it may cause divide error.
Fix this by checking whether 'pixclock' is zero.
The following log reveals it:
divide error: 0000 [#1] PREEMPT SMP KASAN PTI
RIP: 0010:arkfb_set_par+0x10fc/0x24f0
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/arkfb.c | 3 |
1 files changed, 3 insertions, 0 deletions
diff --git a/drivers/video/fbdev/arkfb.c b/drivers/video/fbdev/arkfb.c index edf169d0816e..eb3e47c58c5f 100644 --- a/drivers/video/fbdev/arkfb.c +++ b/drivers/video/fbdev/arkfb.c @@ -566,6 +566,9 @@ static int arkfb_check_var(struct fb_var_screeninfo *var, struct fb_info *info) { int rv, mem, step; + if (!var->pixclock) + return -EINVAL; + /* Find appropriate format */ rv = svga_match_format (arkfb_formats, var, NULL); if (rv < 0) |