From: Eric Dumazet <edumazet@google.com>
Date: Thu, 1 Aug 2013 18:43:08 +0000 (-0700)
Subject: net: add a temporary sanity check in skb_orphan()
X-Git-Tag: next-20130802~67^2~19
X-Git-Url: https://git.karo-electronics.de/?a=commitdiff_plain;h=376c7311bdb6;p=karo-tx-linux.git

net: add a temporary sanity check in skb_orphan()

David suggested to add a BUG_ON() to catch if some layer
sets skb->sk pointer without a corresponding destructor.

As skb can sit in a queue, it's mandatory to make sure the
socket cannot disappear, and it's usually done by taking a
reference on the socket, then releasing it from the skb
destructor.

This patch is a follow-up to commit c34a761231b5
("net: skb_orphan() changes") and will be reverted after
catching all possible offenders if any.

Suggested-by: David Miller <davem@davemloft.net>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
---

diff --git a/include/linux/skbuff.h b/include/linux/skbuff.h
index a95547adff25..d48de687c21f 100644
--- a/include/linux/skbuff.h
+++ b/include/linux/skbuff.h
@@ -1809,6 +1809,8 @@ static inline void skb_orphan(struct sk_buff *skb)
 		skb->destructor(skb);
 		skb->destructor = NULL;
 		skb->sk		= NULL;
+	} else {
+		BUG_ON(skb->sk);
 	}
 }