net: Add safe reverse SKB queue walkers.

Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 9 insertions, 0 deletions

diff --git a/include/linux/skbuff.h b/include/linux/skbuff.h
index bf221d65d9ad..6e946da9d1d6 100644
--- a/include/linux/skbuff.h
+++ b/include/linux/skbuff.h
@@ -1801,6 +1801,15 @@ static inline int pskb_trim_rcsum(struct sk_buff *skb, unsigned int len)
                      prefetch(skb->prev), (skb != (struct sk_buff *)(queue));   \
                      skb = skb->prev)
 
+#define skb_queue_reverse_walk_safe(queue, skb, tmp)                            \
+                for (skb = (queue)->prev, tmp = skb->prev;                      \
+                     skb != (struct sk_buff *)(queue);                          \
+                     skb = tmp, tmp = skb->prev)
+
+#define skb_queue_reverse_walk_from_safe(queue, skb, tmp)                       \
+                for (tmp = skb->prev;                                           \
+                     skb != (struct sk_buff *)(queue);                          \
+                     skb = tmp, tmp = skb->prev)
 
 static inline bool skb_has_frag_list(const struct sk_buff *skb)
 {