From: Wei Chen harperchen1110@gmail.com
[ Upstream commit 92e2a00f2987483e1f9253625828622edd442e61 ]
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 harperchen1110@gmail.com Signed-off-by: Helge Deller deller@gmx.de Signed-off-by: Sasha Levin sashal@kernel.org --- 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 a372a183c1f01..f9c388a8c10e3 100644 --- a/drivers/video/fbdev/nvidia/nvidia.c +++ b/drivers/video/fbdev/nvidia/nvidia.c @@ -763,6 +763,8 @@ 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;