Re: [PATCH] firmware: vpd: Fix section enabled flag on vpd_section_destroy

From: Dmitry Torokhov
Date: Mon Jul 23 2018 - 13:09:19 EST


On Mon, Jul 23, 2018 at 07:48:57PM +0300, Anton Vasilyev wrote:
> static struct ro_vpd and rw_vpd are initialized by vpd_sections_init()
> in vpd_probe() based on header's ro and rw sizes.
> In vpd_remove() vpd_section_destroy() performs deinitialization based
> on enabled flag, which is set to true by vpd_sections_init().
> This leads to call of vpd_section_destroy() on already destroyed section
> for probe-release-probe-release sequence if first probe performs
> ro_vpd initialization and second probe does not initialize it.
>
> The patch adds changing enabled flag on vpd_section_destroy.
>
> Found by Linux Driver Verification project (linuxtesting.org).
>
> Signed-off-by: Anton Vasilyev <vasilyev@xxxxxxxxx>

Good find.

Reviewed-by: Dmitry Torokhov <dmitry.torokhov@xxxxxxxxx>

> ---
> drivers/firmware/google/vpd.c | 1 +
> 1 file changed, 1 insertion(+)
>
> diff --git a/drivers/firmware/google/vpd.c b/drivers/firmware/google/vpd.c
> index e9db895916c3..5347c17c7108 100644
> --- a/drivers/firmware/google/vpd.c
> +++ b/drivers/firmware/google/vpd.c
> @@ -246,6 +246,7 @@ static int vpd_section_destroy(struct vpd_section *sec)
> sysfs_remove_bin_file(vpd_kobj, &sec->bin_attr);
> kfree(sec->raw_name);
> memunmap(sec->baseaddr);
> + sec->enabled = false;
> }
>
> return 0;
> --
> 2.18.0
>

Thanks.

--
Dmitry