Re: [PATCH] fbdev: nvidia: Fix potential divide by zero
From: Helge Deller <deller@gmx.de>
Date: 2023-03-16 13:34:59
Also in:
dri-devel, lkml
On 3/15/23 08:18, Wei Chen wrote:
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 <redacted>
applied all four patches. Thanks! Helge
quoted hunk ↗ jump to hunk
--- 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;