net: Remove all uses of LL_ALLOCATED_SPACE
Herbert Xu [Fri, 18 Nov 2011 02:20:04 +0000 (02:20 +0000)]
net: Remove all uses of LL_ALLOCATED_SPACE

The macro LL_ALLOCATED_SPACE was ill-conceived.  It applies the
alignment to the sum of needed_headroom and needed_tailroom.  As
the amount that is then reserved for head room is needed_headroom
with alignment, this means that the tail room left may be too small.

This patch replaces all uses of LL_ALLOCATED_SPACE with the macro
LL_RESERVED_SPACE and direct reference to needed_tailroom.

This also fixes the problem with needed_headroom changing between
allocating the skb and reserving the head room.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>

net/core/netpoll.c
net/econet/af_econet.c
net/ieee802154/dgram.c
net/ieee802154/raw.c
net/packet/af_packet.c

index cf64c1f..1a7d8e2 100644 (file)
@@ -422,6 +422,7 @@ static void arp_reply(struct sk_buff *skb)
        struct sk_buff *send_skb;
        struct netpoll *np, *tmp;
        unsigned long flags;
+       int hlen, tlen;
        int hits = 0;
 
        if (list_empty(&npinfo->rx_np))
@@ -479,8 +480,9 @@ static void arp_reply(struct sk_buff *skb)
                if (tip != np->local_ip)
                        continue;
 
-               send_skb = find_skb(np, size + LL_ALLOCATED_SPACE(np->dev),
-                                   LL_RESERVED_SPACE(np->dev));
+               hlen = LL_RESERVED_SPACE(np->dev);
+               tlen = np->dev->needed_tailroom;
+               send_skb = find_skb(np, size + hlen + tlen, hlen);
                if (!send_skb)
                        continue;
 
index 1c1f26c..7e717cb 100644 (file)
@@ -322,6 +322,7 @@ static int econet_sendmsg(struct kiocb *iocb, struct socket *sock,
                /* Real hardware Econet.  We're not worthy etc. */
 #ifdef CONFIG_ECONET_NATIVE
                unsigned short proto = 0;
+               int hlen, tlen;
                int res;
 
                if (len + 15 > dev->mtu) {
@@ -331,12 +332,14 @@ static int econet_sendmsg(struct kiocb *iocb, struct socket *sock,
 
                dev_hold(dev);
 
-               skb = sock_alloc_send_skb(sk, len + LL_ALLOCATED_SPACE(dev),
+               hlen = LL_RESERVED_SPACE(dev);
+               tlen = dev->needed_tailroom;
+               skb = sock_alloc_send_skb(sk, len + hlen + tlen,
                                          msg->msg_flags & MSG_DONTWAIT, &err);
                if (skb == NULL)
                        goto out_unlock;
 
-               skb_reserve(skb, LL_RESERVED_SPACE(dev));
+               skb_reserve(skb, hlen);
                skb_reset_network_header(skb);
 
                eb = (struct ec_cb *)&skb->cb;
index faecf64..1b09eaa 100644 (file)
@@ -209,6 +209,7 @@ static int dgram_sendmsg(struct kiocb *iocb, struct sock *sk,
        unsigned mtu;
        struct sk_buff *skb;
        struct dgram_sock *ro = dgram_sk(sk);
+       int hlen, tlen;
        int err;
 
        if (msg->msg_flags & MSG_OOB) {
@@ -229,13 +230,15 @@ static int dgram_sendmsg(struct kiocb *iocb, struct sock *sk,
        mtu = dev->mtu;
        pr_debug("name = %s, mtu = %u\n", dev->name, mtu);
 
-       skb = sock_alloc_send_skb(sk, LL_ALLOCATED_SPACE(dev) + size,
+       hlen = LL_RESERVED_SPACE(dev);
+       tlen = dev->needed_tailroom;
+       skb = sock_alloc_send_skb(sk, hlen + tlen + size,
                        msg->msg_flags & MSG_DONTWAIT,
                        &err);
        if (!skb)
                goto out_dev;
 
-       skb_reserve(skb, LL_RESERVED_SPACE(dev));
+       skb_reserve(skb, hlen);
 
        skb_reset_network_header(skb);
 
index 10970ca..f96bae8 100644 (file)
@@ -108,6 +108,7 @@ static int raw_sendmsg(struct kiocb *iocb, struct sock *sk, struct msghdr *msg,
        struct net_device *dev;
        unsigned mtu;
        struct sk_buff *skb;
+       int hlen, tlen;
        int err;
 
        if (msg->msg_flags & MSG_OOB) {
@@ -137,12 +138,14 @@ static int raw_sendmsg(struct kiocb *iocb, struct sock *sk, struct msghdr *msg,
                goto out_dev;
        }
 
-       skb = sock_alloc_send_skb(sk, LL_ALLOCATED_SPACE(dev) + size,
+       hlen = LL_RESERVED_SPACE(dev);
+       tlen = dev->needed_tailroom;
+       skb = sock_alloc_send_skb(sk, hlen + tlen + size,
                        msg->msg_flags & MSG_DONTWAIT, &err);
        if (!skb)
                goto out_dev;
 
-       skb_reserve(skb, LL_RESERVED_SPACE(dev));
+       skb_reserve(skb, hlen);
 
        skb_reset_mac_header(skb);
        skb_reset_network_header(skb);
index 82a6f34..71c1a75 100644 (file)
@@ -1944,7 +1944,7 @@ static void tpacket_destruct_skb(struct sk_buff *skb)
 
 static int tpacket_fill_skb(struct packet_sock *po, struct sk_buff *skb,
                void *frame, struct net_device *dev, int size_max,
-               __be16 proto, unsigned char *addr)
+               __be16 proto, unsigned char *addr, int hlen)
 {
        union {
                struct tpacket_hdr *h1;
@@ -1978,7 +1978,7 @@ static int tpacket_fill_skb(struct packet_sock *po, struct sk_buff *skb,
                return -EMSGSIZE;
        }
 
-       skb_reserve(skb, LL_RESERVED_SPACE(dev));
+       skb_reserve(skb, hlen);
        skb_reset_network_header(skb);
 
        data = ph.raw + po->tp_hdrlen - sizeof(struct sockaddr_ll);
@@ -2053,6 +2053,7 @@ static int tpacket_snd(struct packet_sock *po, struct msghdr *msg)
        unsigned char *addr;
        int len_sum = 0;
        int status = 0;
+       int hlen, tlen;
 
        mutex_lock(&po->pg_vec_lock);
 
@@ -2101,16 +2102,17 @@ static int tpacket_snd(struct packet_sock *po, struct msghdr *msg)
                }
 
                status = TP_STATUS_SEND_REQUEST;
+               hlen = LL_RESERVED_SPACE(dev);
+               tlen = dev->needed_tailroom;
                skb = sock_alloc_send_skb(&po->sk,
-                               LL_ALLOCATED_SPACE(dev)
-                               + sizeof(struct sockaddr_ll),
+                               hlen + tlen + sizeof(struct sockaddr_ll),
                                0, &err);
 
                if (unlikely(skb == NULL))
                        goto out_status;
 
                tp_len = tpacket_fill_skb(po, skb, ph, dev, size_max, proto,
-                               addr);
+                               addr, hlen);
 
                if (unlikely(tp_len < 0)) {
                        if (po->tp_loss) {
@@ -2207,6 +2209,7 @@ static int packet_snd(struct socket *sock,
        int vnet_hdr_len;
        struct packet_sock *po = pkt_sk(sk);
        unsigned short gso_type = 0;
+       int hlen, tlen;
 
        /*
         *      Get and verify the address.
@@ -2291,8 +2294,9 @@ static int packet_snd(struct socket *sock,
                goto out_unlock;
 
        err = -ENOBUFS;
-       skb = packet_alloc_skb(sk, LL_ALLOCATED_SPACE(dev),
-                              LL_RESERVED_SPACE(dev), len, vnet_hdr.hdr_len,
+       hlen = LL_RESERVED_SPACE(dev);
+       tlen = dev->needed_tailroom;
+       skb = packet_alloc_skb(sk, hlen + tlen, hlen, len, vnet_hdr.hdr_len,
                               msg->msg_flags & MSG_DONTWAIT, &err);
        if (skb == NULL)
                goto out_unlock;