[PATCH 4.9 017/107] net: caif: Add a missing rcu_read_unlock() in caif_flow_cb

[Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>]

4.9-stable review patch.  If anyone has any objections, please let me know.

------------------

From: YueHaibing <yuehaibing@xxxxxxxxxx>

[ Upstream commit 64119e05f7b31e83e2555f6782e6cdc8f81c63f4 ]

Add a missing rcu_read_unlock in the error path

Fixes: c95567c80352 ("caif: added check for potential null return")
Signed-off-by: YueHaibing <yuehaibing@xxxxxxxxxx>
Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx>
Signed-off-by: Sasha Levin <alexander.levin@xxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
 net/caif/caif_dev.c |    4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

--- a/net/caif/caif_dev.c
+++ b/net/caif/caif_dev.c
@@ -131,8 +131,10 @@ static void caif_flow_cb(struct sk_buff
 	caifd = caif_get(skb->dev);
 
 	WARN_ON(caifd == NULL);
-	if (caifd == NULL)
+	if (!caifd) {
+		rcu_read_unlock();
 		return;
+	}
 
 	caifd_hold(caifd);
 	rcu_read_unlock();