variable var->pixclock can be set by user. In case it
equals to zero, divide by zero would occur in nvidiafb_set_par.
Similar crashes have happened in other fbdev drivers. There
is no check and modification on var->pixclock along the call
chain to nvidia_check_var and nvidiafb_set_par. We believe it
could also be triggered in driver nvidia from user site.
Signed-off-by: Wei Chen <harperchen1...@gmail.com>
---
drivers/video/fbdev/nvidia/nvidia.c | 2 ++
1 file changed, 2 insertions(+)
diff --git a/drivers/video/fbdev/nvidia/nvidia.c
b/drivers/video/fbdev/nvidia/nvidia.c
index e60a276b4855..ea4ba3dfb96b 100644
--- a/drivers/video/fbdev/nvidia/nvidia.c
+++ b/drivers/video/fbdev/nvidia/nvidia.c
@@ -764,6 +764,8 @@ static int nvidiafb_check_var(struct fb_var_screeninfo *var,
int pitch, err = 0;
NVTRACE_ENTER();
+ if (!var->pixclock)
+ return -EINVAL;
var->transp.offset = 0;
var->transp.length = 0;
--
2.25.1
