Re: [PATCH] x86/mm/init: Stop printing pgt_buf addresses

[Kees Cook]

On Sat, Feb 29, 2020 at 06:11:20PM -0500, Arvind Sankar wrote:
> This currently leaks kernel physical addresses into userspace.
> 
> Signed-off-by: Arvind Sankar <nivedita@xxxxxxxxxxxx>

Acked-by: Kees Cook <keescook@xxxxxxxxxxxx>

-Kees

> ---
>  arch/x86/mm/init.c | 2 --
>  1 file changed, 2 deletions(-)
> 
> diff --git a/arch/x86/mm/init.c b/arch/x86/mm/init.c
> index e7bb483557c9..dc4711f09cdc 100644
> --- a/arch/x86/mm/init.c
> +++ b/arch/x86/mm/init.c
> @@ -121,8 +121,6 @@ __ref void *alloc_low_pages(unsigned int num)
>  	} else {
>  		pfn = pgt_buf_end;
>  		pgt_buf_end += num;
> -		printk(KERN_DEBUG "BRK [%#010lx, %#010lx] PGTABLE\n",
> -			pfn << PAGE_SHIFT, (pgt_buf_end << PAGE_SHIFT) - 1);
>  	}
>  
>  	for (i = 0; i < num; i++) {
> -- 
> 2.24.1
> 

-- 
Kees Cook