Commit db2ec3c9 authored by Arkadiusz Kubalewski's avatar Arkadiusz Kubalewski Committed by David S. Miller
Browse files

dpll: fix userspace availability of pins 



If parent pin was unregistered but child pin was not, the userspace
would see the "zombie" pins - the ones that were registered with
a parent pin (dpll_pin_on_pin_register(..)).
Technically those are not available - as there is no dpll device in the
system. Do not dump those pins and prevent userspace from any
interaction with them. Provide a unified function to determine if the
pin is available and use it before acting/responding for user requests.

Fixes: 9d71b54b ("dpll: netlink: Add DPLL framework base functions")
Reviewed-by: default avatarJan Glaza <jan.glaza@intel.com>
Reviewed-by: default avatarJiri Pirko <jiri@nvidia.com>
Signed-off-by: default avatarArkadiusz Kubalewski <arkadiusz.kubalewski@intel.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent 830ead5f

drivers/dpll/dpll_netlink.c

+27 −2
Original line number Diff line number Diff line
@@ -553,6 +553,24 @@ __dpll_device_change_ntf(struct dpll_device *dpll) 
	return dpll_device_event_send(DPLL_CMD_DEVICE_CHANGE_NTF, dpll);

}



static bool dpll_pin_available(struct dpll_pin *pin)

{

	struct dpll_pin_ref *par_ref;

	unsigned long i;



	if (!xa_get_mark(&dpll_pin_xa, pin->id, DPLL_REGISTERED))

		return false;

	xa_for_each(&pin->parent_refs, i, par_ref)

		if (xa_get_mark(&dpll_pin_xa, par_ref->pin->id,

				DPLL_REGISTERED))

			return true;

	xa_for_each(&pin->dpll_refs, i, par_ref)

		if (xa_get_mark(&dpll_device_xa, par_ref->dpll->id,

				DPLL_REGISTERED))

			return true;

	return false;

}



/**

 * dpll_device_change_ntf - notify that the dpll device has been changed

 * @dpll: registered dpll pointer
@@ -579,7 +597,7 @@ dpll_pin_event_send(enum dpll_cmd event, struct dpll_pin *pin) 
	int ret = -ENOMEM;

	void *hdr;



	if (WARN_ON(!xa_get_mark(&dpll_pin_xa, pin->id, DPLL_REGISTERED)))

	if (!dpll_pin_available(pin))

		return -ENODEV;



	msg = genlmsg_new(NLMSG_GOODSIZE, GFP_KERNEL);
@@ -1130,6 +1148,10 @@ int dpll_nl_pin_id_get_doit(struct sk_buff *skb, struct genl_info *info) 
	}

	pin = dpll_pin_find_from_nlattr(info);

	if (!IS_ERR(pin)) {

		if (!dpll_pin_available(pin)) {

			nlmsg_free(msg);

			return -ENODEV;

		}

		ret = dpll_msg_add_pin_handle(msg, pin);

		if (ret) {

			nlmsg_free(msg);
@@ -1179,6 +1201,8 @@ int dpll_nl_pin_get_dumpit(struct sk_buff *skb, struct netlink_callback *cb) 


	xa_for_each_marked_start(&dpll_pin_xa, i, pin, DPLL_REGISTERED,

				 ctx->idx) {

		if (!dpll_pin_available(pin))

			continue;

		hdr = genlmsg_put(skb, NETLINK_CB(cb->skb).portid,

				  cb->nlh->nlmsg_seq,

				  &dpll_nl_family, NLM_F_MULTI,
@@ -1441,7 +1465,8 @@ int dpll_pin_pre_doit(const struct genl_split_ops *ops, struct sk_buff *skb, 
	}

	info->user_ptr[0] = xa_load(&dpll_pin_xa,

				    nla_get_u32(info->attrs[DPLL_A_PIN_ID]));

	if (!info->user_ptr[0]) {

	if (!info->user_ptr[0] ||

	    !dpll_pin_available(info->user_ptr[0])) {

		NL_SET_ERR_MSG(info->extack, "pin not found");

		ret = -ENODEV;

		goto unlock_dev;