Re: [PATCH] OMAP: DSS2: OMAPFB: fix potential GPF

[Aaro Koskinen]

Hi,

On Sat, Jun 26, 2021 at 01:33:23AM +0300, Pavel Skripkin wrote:
> In case of allocation failures, all code paths was jumping
> to this code:
> 
> err:
> 	kfree(fbi);
> 	kfree(var);
> 	kfree(fbops);
> 
> 	return r;
> 
> Since all 3 pointers placed on stack and don't initialized, they
> will be filled with some random values, which leads to
> deferencing random pointers in kfree(). Fix it by rewriting
> error handling path.

They are initialized before the first goto:

[...]
	fbi = NULL;
	var = NULL;
	fbops = NULL;

	fbi = kzalloc(sizeof(*fbi), GFP_KERNEL);
	if (fbi == NULL) {
		r = -ENOMEM;
		goto err;
	}
[...]

A.