Re: [PATCH 1/2] lkdtm: fix memory leak of val

From: Kees Cook
Date: Wed Apr 06 2016 - 18:48:17 EST


On Tue, Apr 5, 2016 at 10:11 AM, Sudip Mukherjee
<sudipm.mukherjee@xxxxxxxxx> wrote:
> This case is supposed to read from a page after after it is freed, but
> it missed freeing val if we are not able to get a free page.
>
> Signed-off-by: Sudip Mukherjee <sudip.mukherjee@xxxxxxxxxxxxxxx>

Thanks! Applied to my tree.

-Kees

> ---
> drivers/misc/lkdtm.c | 3 ++-
> 1 file changed, 2 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/misc/lkdtm.c b/drivers/misc/lkdtm.c
> index 5f1a36b..2f0b022 100644
> --- a/drivers/misc/lkdtm.c
> +++ b/drivers/misc/lkdtm.c
> @@ -498,12 +498,13 @@ static void lkdtm_do_action(enum ctype which)
> }
> case CT_READ_BUDDY_AFTER_FREE: {
> unsigned long p = __get_free_page(GFP_KERNEL);
> - int saw, *val = kmalloc(1024, GFP_KERNEL);
> + int saw, *val;
> int *base;
>
> if (!p)
> break;
>
> + val = kmalloc(1024, GFP_KERNEL);
> if (!val)
> break;
>
> --
> 1.9.1
>



--
Kees Cook
Chrome OS & Brillo Security