If bus->state is equal to MDIOBUS_ALLOCATED, mdiobus_free(bus) will free
the "bus". But bus->name is still used in the next line, which will lead
to a use after free.
We can fix it by putting the bus->name in a local variable and then use
the name in the error message without referring to bus to avoid the uaf.
Signed-off-by: Jianglei Nie <[email protected]>
---
drivers/net/ethernet/arc/emac_mdio.c | 5 +++--
1 file changed, 3 insertions(+), 2 deletions(-)
diff --git a/drivers/net/ethernet/arc/emac_mdio.c b/drivers/net/ethernet/arc/emac_mdio.c
index 9acf589b1178..33fd63d227ef 100644
--- a/drivers/net/ethernet/arc/emac_mdio.c
+++ b/drivers/net/ethernet/arc/emac_mdio.c
@@ -134,6 +134,7 @@ int arc_mdio_probe(struct arc_emac_priv *priv)
struct device_node *np = priv->dev->of_node;
struct mii_bus *bus;
int error;
+ const char *name = "Synopsys MII Bus";
bus = mdiobus_alloc();
if (!bus)
@@ -142,7 +143,7 @@ int arc_mdio_probe(struct arc_emac_priv *priv)
priv->bus = bus;
bus->priv = priv;
bus->parent = priv->dev;
- bus->name = "Synopsys MII Bus";
+ bus->name = name;
bus->read = &arc_mdio_read;
bus->write = &arc_mdio_write;
bus->reset = &arc_mdio_reset;
@@ -167,7 +168,7 @@ int arc_mdio_probe(struct arc_emac_priv *priv)
if (error) {
mdiobus_free(bus);
return dev_err_probe(priv->dev, error,
- "cannot register MDIO bus %s\n", bus->name);
+ "cannot register MDIO bus %s\n", name);
}
return 0;
--
2.25.1