[PATCH 4.4 093/158] netrom: fix a memory leak in nr_rx_frame()

Greg Kroah-Hartman
2019-08-02T09:38:59Z

From: Cong Wang <xiyou.wangcong@gmail.com>

[ Upstream commit c8c8218ec5af5d2598381883acbefbf604e56b5e ]

When the skb is associated with a new sock, just assigning
it to skb->sk is not sufficient, we have to set its destructor
to free the sock properly too.

Reported-by: syzbot+d6636a36d3c34bd88938@syzkaller.appspotmail.com
Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
net/netrom/af_netrom.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)

--- a/net/netrom/af_netrom.c
+++ b/net/netrom/af_netrom.c
@@ -870,7 +870,7 @@ int nr_rx_frame(struct sk_buff *skb, str
unsigned short frametype, flags, window, timeout;
int ret;

- skb->sk = NULL; /* Initially we don't know who it's for */
+ skb_orphan(skb);

/*
* skb->data points to the netrom frame start
@@ -969,6 +969,7 @@ int nr_rx_frame(struct sk_buff *skb, str
window = skb->data[20];

skb->sk = make;
+ skb->destructor = sock_efree;
make->sk_state = TCP_ESTABLISHED;

/* Fill in his circuit details */