filter: constify sk_run_filter()

sk_run_filter() doesnt write on skb, change its prototype to reflect
this.

Fix two af_packet comments.

Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 16 insertions, 15 deletions

diff --git a/net/packet/af_packet.c b/net/packet/af_packet.c
index a11c731d2ee..17eafe5b48c 100644
--- a/net/packet/af_packet.c
+++ b/net/packet/af_packet.c
@@ -517,7 +517,8 @@ out_free:
         return err;
 }
 
-static inline unsigned int run_filter(struct sk_buff *skb, struct sock *sk,
+static inline unsigned int run_filter(const struct sk_buff *skb,
+                                      const struct sock *sk,
                                       unsigned int res)
 {
         struct sk_filter *filter;
@@ -532,15 +533,15 @@ static inline unsigned int run_filter(struct sk_buff *skb, struct sock *sk,
 }
 
 /*
-   This function makes lazy skb cloning in hope that most of packets
-   are discarded by BPF.
-
-   Note tricky part: we DO mangle shared skb! skb->data, skb->len
-   and skb->cb are mangled. It works because (and until) packets
-   falling here are owned by current CPU. Output packets are cloned
-   by dev_queue_xmit_nit(), input packets are processed by net_bh
-   sequencially, so that if we return skb to original state on exit,
-   we will not harm anyone.
+ * This function makes lazy skb cloning in hope that most of packets
+ * are discarded by BPF.
+ *
+ * Note tricky part: we DO mangle shared skb! skb->data, skb->len
+ * and skb->cb are mangled. It works because (and until) packets
+ * falling here are owned by current CPU. Output packets are cloned
+ * by dev_queue_xmit_nit(), input packets are processed by net_bh
+ * sequencially, so that if we return skb to original state on exit,
+ * we will not harm anyone.
  */
 
 static int packet_rcv(struct sk_buff *skb, struct net_device *dev,
@@ -566,11 +567,11 @@ static int packet_rcv(struct sk_buff *skb, struct net_device *dev,
 
         if (dev->header_ops) {
                 /* The device has an explicit notion of ll header,
-                   exported to higher levels.
-
-                   Otherwise, the device hides datails of it frame
-                   structure, so that corresponding packet head
-                   never delivered to user.
+                 * exported to higher levels.
+                 *
+                 * Otherwise, the device hides details of its frame
+                 * structure, so that corresponding packet head is
+                 * never delivered to user.
                  */
                 if (sk->sk_type != SOCK_DGRAM)
                         skb_push(skb, skb->data - skb_mac_header(skb));