[PATCH 4.4 157/312] net: dsa: slave: fix of-node leak and phy priority

From: Greg Kroah-Hartman
Date: Fri May 08 2020 - 09:19:14 EST


From: Johan Hovold <johan@xxxxxxxxxx>

commit 0d8f3c67151faaa80e332c254372dca58fb2a9d4 upstream.

Make sure to drop the reference taken by of_parse_phandle() before
returning from dsa_slave_phy_setup().

Note that this also modifies the PHY priority so that any fixed-link
node is only parsed when no phy-handle is given, which is in accordance
with the common scheme for this.

Fixes: 0d8bcdd383b8 ("net: dsa: allow for more complex PHY setups")
Signed-off-by: Johan Hovold <johan@xxxxxxxxxx>
Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

---
net/dsa/slave.c | 7 +++++--
1 file changed, 5 insertions(+), 2 deletions(-)

--- a/net/dsa/slave.c
+++ b/net/dsa/slave.c
@@ -1031,7 +1031,7 @@ static int dsa_slave_phy_setup(struct ds
p->phy_interface = mode;

phy_dn = of_parse_phandle(port_dn, "phy-handle", 0);
- if (of_phy_is_fixed_link(port_dn)) {
+ if (!phy_dn && of_phy_is_fixed_link(port_dn)) {
/* In the case of a fixed PHY, the DT node associated
* to the fixed PHY is the Port DT node
*/
@@ -1041,7 +1041,7 @@ static int dsa_slave_phy_setup(struct ds
return ret;
}
phy_is_fixed = true;
- phy_dn = port_dn;
+ phy_dn = of_node_get(port_dn);
}

if (ds->drv->get_phy_flags)
@@ -1060,6 +1060,7 @@ static int dsa_slave_phy_setup(struct ds
ret = dsa_slave_phy_connect(p, slave_dev, phy_id);
if (ret) {
netdev_err(slave_dev, "failed to connect to phy%d: %d\n", phy_id, ret);
+ of_node_put(phy_dn);
return ret;
}
} else {
@@ -1068,6 +1069,8 @@ static int dsa_slave_phy_setup(struct ds
phy_flags,
p->phy_interface);
}
+
+ of_node_put(phy_dn);
}

if (p->phy && phy_is_fixed)