net: Add utility functions to clear rxhash
In several places 'skb->rxhash = 0' is being done to clear the
rxhash value in an skb. This does not clear l4_rxhash which could
still be set so that the rxhash wouldn't be recalculated on subsequent
call to skb_get_rxhash. This patch adds an explict function to clear
all the rxhash related information in the skb properly.
skb_clear_hash_if_not_l4 clears the rxhash only if it is not marked as
l4_rxhash.
Fixed up places where 'skb->rxhash = 0' was being called.
Signed-off-by: Tom Herbert <therbert@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/include/linux/skbuff.h b/include/linux/skbuff.h
index 4725b95..7deb7ad 100644
--- a/include/linux/skbuff.h
+++ b/include/linux/skbuff.h
@@ -712,6 +712,18 @@
return skb->rxhash;
}
+static inline void skb_clear_hash(struct sk_buff *skb)
+{
+ skb->rxhash = 0;
+ skb->l4_rxhash = 0;
+}
+
+static inline void skb_clear_hash_if_not_l4(struct sk_buff *skb)
+{
+ if (!skb->l4_rxhash)
+ skb_clear_hash(skb);
+}
+
#ifdef NET_SKBUFF_DATA_USES_OFFSET
static inline unsigned char *skb_end_pointer(const struct sk_buff *skb)
{
diff --git a/include/net/dst.h b/include/net/dst.h
index 44995c1..77eb53f 100644
--- a/include/net/dst.h
+++ b/include/net/dst.h
@@ -322,12 +322,11 @@
skb->dev = dev;
/*
- * Clear rxhash so that we can recalulate the hash for the
+ * Clear hash so that we can recalulate the hash for the
* encapsulated packet, unless we have already determine the hash
* over the L4 4-tuple.
*/
- if (!skb->l4_rxhash)
- skb->rxhash = 0;
+ skb_clear_hash_if_not_l4(skb);
skb_set_queue_mapping(skb, 0);
skb_scrub_packet(skb, !net_eq(net, dev_net(dev)));
}