net: dsa: check master device before put

[ Upstream commit 3eb8feeb1708c7dbfd2e97df92a2a407c116606e ]

In the case of pdata, the dsa_cpu_parse function calls dev_put() before
making sure it isn't NULL. Fix this.

Fixes: 71e0bbde0d88 ("net: dsa: Add support for platform data")
Signed-off-by: Vivien Didelot <vivien.didelot@savoirfairelinux.com>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/net/dsa/dsa2.c b/net/dsa/dsa2.c
index 20bc9c56fca05c230477b15d6dad15e02b488800..278b48d70bd93dd03946125988d502f833162257 100644 (file)
--- a/net/dsa/dsa2.c
+++ b/net/dsa/dsa2.c
@@ -496,14 +496,15 @@ static int dsa_cpu_parse(struct dsa_port *port, u32 index,
                if (!ethernet)
                        return -EINVAL;
                ethernet_dev = of_find_net_device_by_node(ethernet);
+               if (!ethernet_dev)
+                       return -EPROBE_DEFER;
        } else {
                ethernet_dev = dsa_dev_to_net_device(ds->cd->netdev[index]);
+               if (!ethernet_dev)
+                       return -EPROBE_DEFER;
                dev_put(ethernet_dev);
        }
 
-       if (!ethernet_dev)
-               return -EPROBE_DEFER;
-
        if (!dst->cpu_dp) {
                dst->cpu_dp = port;
                dst->cpu_dp->netdev = ethernet_dev;