On Fri, Jun 09, 2023 at 09:16:19AM +0300, Dmitry Antipov wrote:
> Handle possible NULL pointer returned by 'get_device()'
> in 'tb_xdomain_alloc()' and 'remove_unplugged_switch()'.
Sorry, but how can that happen?
>
> Found by Linux Verification Center (linuxtesting.org) with SVACE.
>
> Signed-off-by: Dmitry Antipov <dmantipov@xxxxxxxxx>
> ---
> drivers/thunderbolt/icm.c | 5 +++++
> drivers/thunderbolt/xdomain.c | 4 ++++
> 2 files changed, 9 insertions(+)
>
> diff --git a/drivers/thunderbolt/icm.c b/drivers/thunderbolt/icm.c
> index 86521ebb2579..40ab6104a437 100644
> --- a/drivers/thunderbolt/icm.c
> +++ b/drivers/thunderbolt/icm.c
> @@ -2035,6 +2035,11 @@ static void remove_unplugged_switch(struct tb_switch *sw)
> {
> struct device *parent = get_device(sw->dev.parent);
>
> + if (!parent) {
This will never fail, how did you test this?
> + tb_warn(sw->tb, "no parent of switch %pUb\n", sw->uuid);
> + return;
> + }
> +
> pm_runtime_get_sync(parent);
>
> /*
> diff --git a/drivers/thunderbolt/xdomain.c b/drivers/thunderbolt/xdomain.c
> index e2b54887d331..a0ee683d752e 100644
> --- a/drivers/thunderbolt/xdomain.c
> +++ b/drivers/thunderbolt/xdomain.c
> @@ -1883,6 +1883,8 @@ struct tb_xdomain *tb_xdomain_alloc(struct tb *tb, struct device *parent,
>
> device_initialize(&xd->dev);
> xd->dev.parent = get_device(parent);
> + if (!xd->dev.parent)
Again, how did you test this? How can that ever happen?
thanks,
greg k-h
