Commit 8fb479a4 authored by Antonio Quartulli's avatar Antonio Quartulli Committed by David S. Miller
Browse files

netpoll: fix rx_hook() interface by passing the skb 



Right now skb->data is passed to rx_hook() even if the skb
has not been linearised and without giving rx_hook() a way
to linearise it.

Change the rx_hook() interface and make it accept the skb
and the offset to the UDP payload as arguments. rx_hook() is
also renamed to rx_skb_hook() to ensure that out of the tree
users notice the API change.

In this way any rx_skb_hook() implementation can perform all
the needed operations to properly (and safely) access the
skb data.

Signed-off-by: default avatarAntonio Quartulli <antonio@meshcoding.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent c7c6effd

include/linux/netpoll.h

+3 −2
Original line number Diff line number Diff line
@@ -24,7 +24,8 @@ struct netpoll { 
	struct net_device *dev;

	char dev_name[IFNAMSIZ];

	const char *name;

	void (*rx_hook)(struct netpoll *, int, char *, int);

	void (*rx_skb_hook)(struct netpoll *np, int source, struct sk_buff *skb,

			    int offset, int len);



	union inet_addr local_ip, remote_ip;

	bool ipv6;
@@ -41,7 +42,7 @@ struct netpoll_info { 
	unsigned long rx_flags;

	spinlock_t rx_lock;

	struct semaphore dev_lock;

	struct list_head rx_np; /* netpolls that registered an rx_hook */

	struct list_head rx_np; /* netpolls that registered an rx_skb_hook */



	struct sk_buff_head neigh_tx; /* list of neigh requests to reply to */

	struct sk_buff_head txq;

net/core/netpoll.c

+18 −13
Original line number Diff line number Diff line
@@ -636,8 +636,9 @@ static void netpoll_neigh_reply(struct sk_buff *skb, struct netpoll_info *npinfo 


			netpoll_send_skb(np, send_skb);



			/* If there are several rx_hooks for the same address,

			   we're fine by sending a single reply */

			/* If there are several rx_skb_hooks for the same

			 * address we're fine by sending a single reply

			 */

			break;

		}

		spin_unlock_irqrestore(&npinfo->rx_lock, flags);
@@ -719,8 +720,9 @@ static void netpoll_neigh_reply(struct sk_buff *skb, struct netpoll_info *npinfo 


			netpoll_send_skb(np, send_skb);



			/* If there are several rx_hooks for the same address,

			   we're fine by sending a single reply */

			/* If there are several rx_skb_hooks for the same

			 * address, we're fine by sending a single reply

			 */

			break;

		}

		spin_unlock_irqrestore(&npinfo->rx_lock, flags);
@@ -756,11 +758,12 @@ static bool pkt_is_ns(struct sk_buff *skb) 


int __netpoll_rx(struct sk_buff *skb, struct netpoll_info *npinfo)

{

	int proto, len, ulen;

	int hits = 0;

	int proto, len, ulen, data_len;

	int hits = 0, offset;

	const struct iphdr *iph;

	struct udphdr *uh;

	struct netpoll *np, *tmp;

	uint16_t source;



	if (list_empty(&npinfo->rx_np))

		goto out;
@@ -820,7 +823,10 @@ int __netpoll_rx(struct sk_buff *skb, struct netpoll_info *npinfo) 


		len -= iph->ihl*4;

		uh = (struct udphdr *)(((char *)iph) + iph->ihl*4);

		offset = (unsigned char *)(uh + 1) - skb->data;

		ulen = ntohs(uh->len);

		data_len = skb->len - offset;

		source = ntohs(uh->source);



		if (ulen != len)

			goto out;
@@ -834,9 +840,7 @@ int __netpoll_rx(struct sk_buff *skb, struct netpoll_info *npinfo) 
			if (np->local_port && np->local_port != ntohs(uh->dest))

				continue;



			np->rx_hook(np, ntohs(uh->source),

				       (char *)(uh+1),

				       ulen - sizeof(struct udphdr));

			np->rx_skb_hook(np, source, skb, offset, data_len);

			hits++;

		}

	} else {
@@ -859,7 +863,10 @@ int __netpoll_rx(struct sk_buff *skb, struct netpoll_info *npinfo) 
		if (!pskb_may_pull(skb, sizeof(struct udphdr)))

			goto out;

		uh = udp_hdr(skb);

		offset = (unsigned char *)(uh + 1) - skb->data;

		ulen = ntohs(uh->len);

		data_len = skb->len - offset;

		source = ntohs(uh->source);

		if (ulen != skb->len)

			goto out;

		if (udp6_csum_init(skb, uh, IPPROTO_UDP))
@@ -872,9 +879,7 @@ int __netpoll_rx(struct sk_buff *skb, struct netpoll_info *npinfo) 
			if (np->local_port && np->local_port != ntohs(uh->dest))

				continue;



			np->rx_hook(np, ntohs(uh->source),

				       (char *)(uh+1),

				       ulen - sizeof(struct udphdr));

			np->rx_skb_hook(np, source, skb, offset, data_len);

			hits++;

		}

#endif
@@ -1062,7 +1067,7 @@ int __netpoll_setup(struct netpoll *np, struct net_device *ndev, gfp_t gfp) 


	npinfo->netpoll = np;



	if (np->rx_hook) {

	if (np->rx_skb_hook) {

		spin_lock_irqsave(&npinfo->rx_lock, flags);

		npinfo->rx_flags |= NETPOLL_RX_ENABLED;

		list_add_tail(&np->rx, &npinfo->rx_np);

CRA Git | Maintained and supported by SUSTech CRA and CCSE