From 8640f8dc6d657ebfb4e67c202ad32c5457858a13 Mon Sep 17 00:00:00 2001 From: Russell King Date: Tue, 3 Mar 2020 15:01:46 +0000 Subject: net: dsa: fix phylink_start()/phylink_stop() calls Place phylink_start()/phylink_stop() inside dsa_port_enable() and dsa_port_disable(), which ensures that we call phylink_stop() before tearing down phylink - which is a documented requirement. Failure to do so can cause use-after-free bugs. Fixes: 0e27921816ad ("net: dsa: Use PHYLINK for the CPU/DSA ports") Signed-off-by: Russell King Reviewed-by: Andrew Lunn Signed-off-by: David S. Miller --- net/dsa/dsa_priv.h | 2 ++ net/dsa/port.c | 32 ++++++++++++++++++++++++++------ net/dsa/slave.c | 8 ++------ 3 files changed, 30 insertions(+), 12 deletions(-) (limited to 'net/dsa') diff --git a/net/dsa/dsa_priv.h b/net/dsa/dsa_priv.h index a7662e7a691d..760e6ea3178a 100644 --- a/net/dsa/dsa_priv.h +++ b/net/dsa/dsa_priv.h @@ -117,7 +117,9 @@ static inline struct net_device *dsa_master_find_slave(struct net_device *dev, /* port.c */ int dsa_port_set_state(struct dsa_port *dp, u8 state, struct switchdev_trans *trans); +int dsa_port_enable_rt(struct dsa_port *dp, struct phy_device *phy); int dsa_port_enable(struct dsa_port *dp, struct phy_device *phy); +void dsa_port_disable_rt(struct dsa_port *dp); void dsa_port_disable(struct dsa_port *dp); int dsa_port_bridge_join(struct dsa_port *dp, struct net_device *br); void dsa_port_bridge_leave(struct dsa_port *dp, struct net_device *br); diff --git a/net/dsa/port.c b/net/dsa/port.c index 774facb8d547..ed7dabb57985 100644 --- a/net/dsa/port.c +++ b/net/dsa/port.c @@ -63,7 +63,7 @@ static void dsa_port_set_state_now(struct dsa_port *dp, u8 state) pr_err("DSA: failed to set STP state %u (%d)\n", state, err); } -int dsa_port_enable(struct dsa_port *dp, struct phy_device *phy) +int dsa_port_enable_rt(struct dsa_port *dp, struct phy_device *phy) { struct dsa_switch *ds = dp->ds; int port = dp->index; @@ -78,14 +78,31 @@ int dsa_port_enable(struct dsa_port *dp, struct phy_device *phy) if (!dp->bridge_dev) dsa_port_set_state_now(dp, BR_STATE_FORWARDING); + if (dp->pl) + phylink_start(dp->pl); + return 0; } -void dsa_port_disable(struct dsa_port *dp) +int dsa_port_enable(struct dsa_port *dp, struct phy_device *phy) +{ + int err; + + rtnl_lock(); + err = dsa_port_enable_rt(dp, phy); + rtnl_unlock(); + + return err; +} + +void dsa_port_disable_rt(struct dsa_port *dp) { struct dsa_switch *ds = dp->ds; int port = dp->index; + if (dp->pl) + phylink_stop(dp->pl); + if (!dp->bridge_dev) dsa_port_set_state_now(dp, BR_STATE_DISABLED); @@ -93,6 +110,13 @@ void dsa_port_disable(struct dsa_port *dp) ds->ops->port_disable(ds, port); } +void dsa_port_disable(struct dsa_port *dp) +{ + rtnl_lock(); + dsa_port_disable_rt(dp); + rtnl_unlock(); +} + int dsa_port_bridge_join(struct dsa_port *dp, struct net_device *br) { struct dsa_notifier_bridge_info info = { @@ -614,10 +638,6 @@ static int dsa_port_phylink_register(struct dsa_port *dp) goto err_phy_connect; } - rtnl_lock(); - phylink_start(dp->pl); - rtnl_unlock(); - return 0; err_phy_connect: diff --git a/net/dsa/slave.c b/net/dsa/slave.c index 088c886e609e..ddc0f9236928 100644 --- a/net/dsa/slave.c +++ b/net/dsa/slave.c @@ -88,12 +88,10 @@ static int dsa_slave_open(struct net_device *dev) goto clear_allmulti; } - err = dsa_port_enable(dp, dev->phydev); + err = dsa_port_enable_rt(dp, dev->phydev); if (err) goto clear_promisc; - phylink_start(dp->pl); - return 0; clear_promisc: @@ -114,9 +112,7 @@ static int dsa_slave_close(struct net_device *dev) struct net_device *master = dsa_slave_to_master(dev); struct dsa_port *dp = dsa_slave_to_port(dev); - phylink_stop(dp->pl); - - dsa_port_disable(dp); + dsa_port_disable_rt(dp); dev_mc_unsync(master, dev); dev_uc_unsync(master, dev); -- cgit v1.2.3 From a20f997010c4ec76eaa55b8cc047d76dcac69f70 Mon Sep 17 00:00:00 2001 From: Andrew Lunn Date: Wed, 11 Mar 2020 16:24:24 +0100 Subject: net: dsa: Don't instantiate phylink for CPU/DSA ports unless needed By default, DSA drivers should configure CPU and DSA ports to their maximum speed. In many configurations this is sufficient to make the link work. In some cases it is necessary to configure the link to run slower, e.g. because of limitations of the SoC it is connected to. Or back to back PHYs are used and the PHY needs to be driven in order to establish link. In this case, phylink is used. Only instantiate phylink if it is required. If there is no PHY, or no fixed link properties, phylink can upset a link which works in the default configuration. Fixes: 0e27921816ad ("net: dsa: Use PHYLINK for the CPU/DSA ports") Signed-off-by: Andrew Lunn Signed-off-by: David S. Miller --- net/dsa/port.c | 12 +++++++++--- 1 file changed, 9 insertions(+), 3 deletions(-) (limited to 'net/dsa') diff --git a/net/dsa/port.c b/net/dsa/port.c index ed7dabb57985..ec13dc666788 100644 --- a/net/dsa/port.c +++ b/net/dsa/port.c @@ -648,9 +648,14 @@ err_phy_connect: int dsa_port_link_register_of(struct dsa_port *dp) { struct dsa_switch *ds = dp->ds; + struct device_node *phy_np; - if (!ds->ops->adjust_link) - return dsa_port_phylink_register(dp); + if (!ds->ops->adjust_link) { + phy_np = of_parse_phandle(dp->dn, "phy-handle", 0); + if (of_phy_is_fixed_link(dp->dn) || phy_np) + return dsa_port_phylink_register(dp); + return 0; + } dev_warn(ds->dev, "Using legacy PHYLIB callbacks. Please migrate to PHYLINK!\n"); @@ -665,11 +670,12 @@ void dsa_port_link_unregister_of(struct dsa_port *dp) { struct dsa_switch *ds = dp->ds; - if (!ds->ops->adjust_link) { + if (!ds->ops->adjust_link && dp->pl) { rtnl_lock(); phylink_disconnect_phy(dp->pl); rtnl_unlock(); phylink_destroy(dp->pl); + dp->pl = NULL; return; } -- cgit v1.2.3