[PATCH] net, bluetooth: don't attempt to free a channel that wasn't created

We may currently attempt to free a channel which wasn't created due to
an error in the initialization path, this would cause a NULL ptr deref.

Introduced in commit 61d6ef3e ("Bluetooth: Make better use of l2cap_chan
reference counting").

Signed-off-by: Sasha Levin <redacted>
---
 net/bluetooth/l2cap_sock.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/net/bluetooth/l2cap_sock.c b/net/bluetooth/l2cap_sock.c
index 083f2bf..66c295a 100644
--- a/net/bluetooth/l2cap_sock.c
+++ b/net/bluetooth/l2cap_sock.c

@@ -1083,7 +1083,8 @@ static void l2cap_sock_destruct(struct sock *sk)
 {
 	BT_DBG("sk %p", sk);
 
-	l2cap_chan_put(l2cap_pi(sk)->chan);
+	if (l2cap_pi(sk)->chan)
+		l2cap_chan_put(l2cap_pi(sk)->chan);
 	if (l2cap_pi(sk)->rx_busy_skb) {
 		kfree_skb(l2cap_pi(sk)->rx_busy_skb);
 		l2cap_pi(sk)->rx_busy_skb = NULL;

-- 
1.7.12