Re: [PATCH v2] virt: vbox: fix memory leak in hgcm_call_preprocess_linaddr

[Hans de Goede]

Hi,

On 30-09-2019 22:42, Navid Emamdoost wrote:
> In hgcm_call_preprocess_linaddr memory is allocated for bounce_buf but
> is not released if copy_form_user fails. In order to prevent memory leak
> in case of failure, the assignment to bounce_buf_ret is moved before the
> error check. This way the allocated bounce_buf will be released by the
> caller.
>
> Fixes: 579db9d45cb4 ("virt: Add vboxguest VMMDEV communication code")
> Signed-off-by: Navid Emamdoost <navid.emamdoost@xxxxxxxxx>

Thank you.

Patch looks good to me:

Reviewed-by: Hans de Goede <hdegoede@xxxxxxxxxx>

Regards,

Hans



> ---
>   drivers/virt/vboxguest/vboxguest_utils.c | 3 ++-
>   1 file changed, 2 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/virt/vboxguest/vboxguest_utils.c b/drivers/virt/vboxguest/vboxguest_utils.c
> index 75fd140b02ff..43c391626a00 100644
> --- a/drivers/virt/vboxguest/vboxguest_utils.c
> +++ b/drivers/virt/vboxguest/vboxguest_utils.c
> @@ -220,6 +220,8 @@ static int hgcm_call_preprocess_linaddr(
>   	if (!bounce_buf)
>   		return -ENOMEM;
>   
> +	*bounce_buf_ret = bounce_buf;
> +
>   	if (copy_in) {
>   		ret = copy_from_user(bounce_buf, (void __user *)buf, len);
>   		if (ret)
> @@ -228,7 +230,6 @@ static int hgcm_call_preprocess_linaddr(
>   		memset(bounce_buf, 0, len);
>   	}
>   
> -	*bounce_buf_ret = bounce_buf;
>   	hgcm_call_add_pagelist_size(bounce_buf, len, extra);
>   	return 0;
>   }