| Message ID | 20200130174451.17951-2-michael@walle.cc |
|---|---|
| State | Accepted |
| Delegated to: | David Miller |
| Headers | show |
| Series | [net-next,1/2] net: mdio: of: fix potential NULL pointer derefernce | expand |
On Thu, Jan 30, 2020 at 06:44:51PM +0100, Michael Walle wrote: > If phydev->mii_ts is set by the PHY driver, it will always be > overwritten in of_mdiobus_register_phy(). Fix it. Also make sure, that > the unregister() doesn't do anything if the mii_timestamper was provided by > the PHY driver. > > Fixes: 1dca22b18421 ("net: mdio: of: Register discovered MII time stampers.") > Signed-off-by: Michael Walle <michael@walle.cc> Thanks for the fix. Acked-by: Richard Cochran <richardcochran@gmail.com>
diff --git a/drivers/net/phy/mii_timestamper.c b/drivers/net/phy/mii_timestamper.c index 2f12c5d901df..b71b7456462d 100644 --- a/drivers/net/phy/mii_timestamper.c +++ b/drivers/net/phy/mii_timestamper.c @@ -111,6 +111,13 @@ void unregister_mii_timestamper(struct mii_timestamper *mii_ts) struct mii_timestamping_desc *desc; struct list_head *this; + /* mii_timestamper statically registered by the PHY driver won't use the + * register_mii_timestamper() and thus don't have ->device set. Don't + * try to unregister these. + */ + if (!mii_ts->device) + return; + mutex_lock(&tstamping_devices_lock); list_for_each(this, &mii_timestamping_devices) { desc = list_entry(this, struct mii_timestamping_desc, list); diff --git a/drivers/of/of_mdio.c b/drivers/of/of_mdio.c index db0ed5879803..8270bbf505fb 100644 --- a/drivers/of/of_mdio.c +++ b/drivers/of/of_mdio.c @@ -124,7 +124,13 @@ static int of_mdiobus_register_phy(struct mii_bus *mdio, of_node_put(child); return rc; } - phy->mii_ts = mii_ts; + + /* phy->mii_ts may already be defined by the PHY driver. A + * mii_timestamper probed via the device tree will still have + * precedence. + */ + if (mii_ts) + phy->mii_ts = mii_ts; dev_dbg(&mdio->dev, "registered phy %pOFn at address %i\n", child, addr);
If phydev->mii_ts is set by the PHY driver, it will always be overwritten in of_mdiobus_register_phy(). Fix it. Also make sure, that the unregister() doesn't do anything if the mii_timestamper was provided by the PHY driver. Fixes: 1dca22b18421 ("net: mdio: of: Register discovered MII time stampers.") Signed-off-by: Michael Walle <michael@walle.cc> --- drivers/net/phy/mii_timestamper.c | 7 +++++++ drivers/of/of_mdio.c | 8 +++++++- 2 files changed, 14 insertions(+), 1 deletion(-)