1 files changed, 60 insertions, 10 deletions

diff --git a/net/core/skbuff.c b/net/core/skbuff.c
index 1e3e008..65a74e1 100644
--- a/net/core/skbuff.c
+++ b/net/core/skbuff.c
@@ -354,7 +354,7 @@ EXPORT_SYMBOL(build_skb);
 
 struct napi_alloc_cache {
 	struct page_frag_cache page;
-	size_t skb_count;
+	unsigned int skb_count;
 	void *skb_cache[NAPI_SKB_CACHE_SIZE];
 };
 
@@ -2656,7 +2656,9 @@ int skb_shift(struct sk_buff *tgt, struct sk_buff *skb, int shiftlen)
 	struct skb_frag_struct *fragfrom, *fragto;
 
 	BUG_ON(shiftlen > skb->len);
-	BUG_ON(skb_headlen(skb));	/* Would corrupt stream */
+
+	if (skb_headlen(skb))
+		return 0;
 
 	todo = shiftlen;
 	from = 0;
@@ -3712,21 +3714,29 @@ int sock_queue_err_skb(struct sock *sk, struct sk_buff *skb)
 }
 EXPORT_SYMBOL(sock_queue_err_skb);
 
+static bool is_icmp_err_skb(const struct sk_buff *skb)
+{
+	return skb && (SKB_EXT_ERR(skb)->ee.ee_origin == SO_EE_ORIGIN_ICMP ||
+		       SKB_EXT_ERR(skb)->ee.ee_origin == SO_EE_ORIGIN_ICMP6);
+}
+
 struct sk_buff *sock_dequeue_err_skb(struct sock *sk)
 {
 	struct sk_buff_head *q = &sk->sk_error_queue;
-	struct sk_buff *skb, *skb_next;
+	struct sk_buff *skb, *skb_next = NULL;
+	bool icmp_next = false;
 	unsigned long flags;
-	int err = 0;
 
 	spin_lock_irqsave(&q->lock, flags);
 	skb = __skb_dequeue(q);
 	if (skb && (skb_next = skb_peek(q)))
-		err = SKB_EXT_ERR(skb_next)->ee.ee_errno;
+		icmp_next = is_icmp_err_skb(skb_next);
 	spin_unlock_irqrestore(&q->lock, flags);
 
-	sk->sk_err = err;
-	if (err)
+	if (is_icmp_err_skb(skb) && !icmp_next)
+		sk->sk_err = 0;
+
+	if (skb_next)
 		sk->sk_error_report(sk);
 
 	return skb;
@@ -3838,10 +3848,18 @@ void __skb_tstamp_tx(struct sk_buff *orig_skb,
 	if (!skb_may_tx_timestamp(sk, tsonly))
 		return;
 
-	if (tsonly)
-		skb = alloc_skb(0, GFP_ATOMIC);
-	else
+	if (tsonly) {
+#ifdef CONFIG_INET
+		if ((sk->sk_tsflags & SOF_TIMESTAMPING_OPT_STATS) &&
+		    sk->sk_protocol == IPPROTO_TCP &&
+		    sk->sk_type == SOCK_STREAM)
+			skb = tcp_get_timestamping_opt_stats(sk);
+		else
+#endif
+			skb = alloc_skb(0, GFP_ATOMIC);
+	} else {
 		skb = skb_clone(orig_skb, GFP_ATOMIC);
+	}
 	if (!skb)
 		return;
 
@@ -4913,3 +4931,35 @@ struct sk_buff *pskb_extract(struct sk_buff *skb, int off,
 	return clone;
 }
 EXPORT_SYMBOL(pskb_extract);
+
+/**
+ * skb_condense - try to get rid of fragments/frag_list if possible
+ * @skb: buffer
+ *
+ * Can be used to save memory before skb is added to a busy queue.
+ * If packet has bytes in frags and enough tail room in skb->head,
+ * pull all of them, so that we can free the frags right now and adjust
+ * truesize.
+ * Notes:
+ *	We do not reallocate skb->head thus can not fail.
+ *	Caller must re-evaluate skb->truesize if needed.
+ */
+void skb_condense(struct sk_buff *skb)
+{
+	if (skb->data_len) {
+		if (skb->data_len > skb->end - skb->tail ||
+		    skb_cloned(skb))
+			return;
+
+		/* Nice, we can free page frag(s) right now */
+		__pskb_pull_tail(skb, skb->data_len);
+	}
+	/* At this point, skb->truesize might be over estimated,
+	 * because skb had a fragment, and fragments do not tell
+	 * their truesize.
+	 * When we pulled its content into skb->head, fragment
+	 * was freed, but __pskb_pull_tail() could not possibly
+	 * adjust skb->truesize, not knowing the frag truesize.
+	 */
+	skb->truesize = SKB_TRUESIZE(skb_end_offset(skb));
+}