wext: optimise, comment and fix event sending (4f45b2cd) · Commits · e / devices / android_kernel_oneplus_sm8150

net/wireless/wext.c

+57 −57

Original line number	Original line	Diff line number	Diff line
	@@ -1300,22 +1300,15 @@ static void wireless_nlevent_process(struct work_struct *work)

	static DECLARE_WORK(wireless_nlevent_work, wireless_nlevent_process);		static DECLARE_WORK(wireless_nlevent_work, wireless_nlevent_process);

	/* ---------------------------------------------------------------- */		static struct nlmsghdr rtnetlink_ifinfo_prep(struct net_device dev,
	/*		struct sk_buff *skb)
	* Fill a rtnetlink message with our event data.
	* Note that we propage only the specified event and don't dump the
	* current wireless config. Dumping the wireless config is far too
	* expensive (for each parameter, the driver need to query the hardware).
	*/
	static int rtnetlink_fill_iwinfo(struct sk_buff skb, struct net_device dev,
	int type, char *event, int event_len)
	{		{
	struct ifinfomsg *r;		struct ifinfomsg *r;
	struct nlmsghdr *nlh;		struct nlmsghdr *nlh;

	nlh = nlmsg_put(skb, 0, 0, type, sizeof(*r), 0);		nlh = nlmsg_put(skb, 0, 0, RTM_NEWLINK, sizeof(*r), 0);
	if (nlh == NULL)		if (!nlh)
	return -EMSGSIZE;		return NULL;

	r = nlmsg_data(nlh);		r = nlmsg_data(nlh);
	r->ifi_family = AF_UNSPEC;		r->ifi_family = AF_UNSPEC;
	@@ -1326,45 +1319,14 @@ static int rtnetlink_fill_iwinfo(struct sk_buff skb, struct net_device dev,
	r->ifi_change = 0; /* Wireless changes don't affect those flags */		r->ifi_change = 0; /* Wireless changes don't affect those flags */

	NLA_PUT_STRING(skb, IFLA_IFNAME, dev->name);		NLA_PUT_STRING(skb, IFLA_IFNAME, dev->name);
	/* Add the wireless events in the netlink packet */
	NLA_PUT(skb, IFLA_WIRELESS, event_len, event);

	return nlmsg_end(skb, nlh);

			return nlh;
	nla_put_failure:		nla_put_failure:
	nlmsg_cancel(skb, nlh);		nlmsg_cancel(skb, nlh);
	return -EMSGSIZE;		return NULL;
	}

	/* ---------------------------------------------------------------- */
	/*
	* Create and broadcast and send it on the standard rtnetlink socket
	* This is a pure clone rtmsg_ifinfo() in net/core/rtnetlink.c
	* Andrzej Krzysztofowicz mandated that I used a IFLA_XXX field
	* within a RTM_NEWLINK event.
	*/
	static void rtmsg_iwinfo(struct net_device dev, char event, int event_len)
	{
	struct sk_buff *skb;
	int err;

	skb = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_ATOMIC);
	if (!skb)
	return;

	err = rtnetlink_fill_iwinfo(skb, dev, RTM_NEWLINK, event, event_len);
	if (err < 0) {
	WARN_ON(err == -EMSGSIZE);
	kfree_skb(skb);
	return;
	}		}

	NETLINK_CB(skb).dst_group = RTNLGRP_LINK;
	skb_queue_tail(&dev_net(dev)->wext_nlevents, skb);
	schedule_work(&wireless_nlevent_work);
	}

	/* ---------------------------------------------------------------- */
	/*		/*
	* Main event dispatcher. Called from other parts and drivers.		* Main event dispatcher. Called from other parts and drivers.
	* Send the event on the appropriate channels.		* Send the event on the appropriate channels.
	@@ -1383,6 +1345,9 @@ void wireless_send_event(struct net_device * dev,
	int wrqu_off = 0; /* Offset in wrqu */		int wrqu_off = 0; /* Offset in wrqu */
	/* Don't "optimise" the following variable, it will crash */		/* Don't "optimise" the following variable, it will crash */
	unsigned cmd_index; /* MUST be unsigned */		unsigned cmd_index; /* MUST be unsigned */
			struct sk_buff *skb;
			struct nlmsghdr *nlh;
			struct nlattr *nla;

	/* Get the description of the Event */		/* Get the description of the Event */
	if (cmd <= SIOCIWLAST) {		if (cmd <= SIOCIWLAST) {
	@@ -1430,25 +1395,60 @@ void wireless_send_event(struct net_device * dev,
	hdr_len = event_type_size[descr->header_type];		hdr_len = event_type_size[descr->header_type];
	event_len = hdr_len + extra_len;		event_len = hdr_len + extra_len;

	/* Create temporary buffer to hold the event */		/*
	event = kmalloc(event_len, GFP_ATOMIC);		* The problem for 64/32 bit.
	if (event == NULL)		*
			* On 64-bit, a regular event is laid out as follows:
			* \| 0 \| 1 \| 2 \| 3 \| 4 \| 5 \| 6 \| 7 \|
			* \| event.len \| event.cmd \| p a d d i n g \|
			* \| wrqu data ... (with the correct size) \|
			*
			* This padding exists because we manipulate event->u,
			* and 'event' is not packed.
			*
			* An iw_point event is laid out like this instead:
			* \| 0 \| 1 \| 2 \| 3 \| 4 \| 5 \| 6 \| 7 \|
			* \| event.len \| event.cmd \| p a d d i n g \|
			* \| iwpnt.len \| iwpnt.flg \| p a d d i n g \|
			* \| extra data ...
			*
			* The second padding exists because struct iw_point is extended,
			* but this depends on the platform...
			*
			* On 32-bit, all the padding shouldn't be there.
			*/

			skb = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_ATOMIC);
			if (!skb)
			return;

			/* Send via the RtNetlink event channel */
			nlh = rtnetlink_ifinfo_prep(dev, skb);
			if (WARN_ON(!nlh)) {
			kfree_skb(skb);
	return;		return;
			}

	/* Fill event */		/* Add the wireless events in the netlink packet */
			nla = nla_reserve(skb, IFLA_WIRELESS, event_len);
			if (!nla) {
			kfree_skb(skb);
			return;
			}
			event = nla_data(nla);

			/* Fill event - first clear to avoid data leaking */
			memset(event, 0, hdr_len);
	event->len = event_len;		event->len = event_len;
	event->cmd = cmd;		event->cmd = cmd;
	memcpy(&event->u, ((char *) wrqu) + wrqu_off, hdr_len - IW_EV_LCP_LEN);		memcpy(&event->u, ((char *) wrqu) + wrqu_off, hdr_len - IW_EV_LCP_LEN);
	if (extra)		if (extra_len)
	memcpy(((char *) event) + hdr_len, extra, extra_len);		memcpy(((char *) event) + hdr_len, extra, extra_len);

	/* Send via the RtNetlink event channel */		nlmsg_end(skb, nlh);
	rtmsg_iwinfo(dev, (char *) event, event_len);

	/* Cleanup */
	kfree(event);

	return; /* Always success, I guess ;-) */		skb_queue_tail(&dev_net(dev)->wext_nlevents, skb);
			schedule_work(&wireless_nlevent_work);
	}		}
	EXPORT_SYMBOL(wireless_send_event);		EXPORT_SYMBOL(wireless_send_event);