From: Sowmini Varadhan <sowmini.varadhan@oracle.com>
Date: Thu, 6 Jul 2017 15:15:07 +0000 (-0700)
Subject: net/sock: add WARN_ON(parent->sk) in sock_graft()
X-Git-Tag: v4.1.12-107.0.20170801_2000~61
X-Git-Url: https://www.infradead.org/git/?a=commitdiff_plain;h=b347809061bbe94dcd39d38306139944ec2f57b8;p=users%2Fjedix%2Flinux-maple.git

net/sock: add WARN_ON(parent->sk) in sock_graft()

sock_graft() unilaterally sets up parent->sk based on the
assumption that the existing parent->sk is null. If this
condition is not true, then the existing parent->sk would
be leaked, so add a WARN_ON() to alert callers who may fall
in this category.

Orabug: 26477756

Signed-off-by: Sowmini Varadhan <sowmini.varadhan@oracle.com>
Reviewed-by: Yuval Shaia <yuval.shaia@oracle.com>
---

diff --git a/include/net/sock.h b/include/net/sock.h
index 5374c0dff793..71431f99fcfc 100644
--- a/include/net/sock.h
+++ b/include/net/sock.h
@@ -1686,6 +1686,7 @@ static inline void sock_orphan(struct sock *sk)
 
 static inline void sock_graft(struct sock *sk, struct socket *parent)
 {
+	WARN_ON(parent->sk);
 	write_lock_bh(&sk->sk_callback_lock);
 	sk->sk_wq = parent->wq;
 	parent->sk = sk;