From: Heiner Kallweit <hkallweit1@xxxxxxxxx> [ Upstream commit 867dbe784c5010a466f00a7d1467c1c5ea569c75 ] The caller may pass any value as addr, what may result in an out-of-bounds access to array mdio_map. One existing case is stmmac_init_phy() that may pass -1 as addr. Therefore validate addr before using it. Fixes: 7f854420fbfe ("phy: Add API for {un}registering an mdio device to a bus.") Signed-off-by: Heiner Kallweit <hkallweit1@xxxxxxxxx> Reviewed-by: Andrew Lunn <andrew@xxxxxxx> Link: https://lore.kernel.org/r/cdf664ea-3312-e915-73f8-021678d08887@xxxxxxxxx Signed-off-by: Paolo Abeni <pabeni@xxxxxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> --- drivers/net/phy/mdio_bus.c | 7 ++++++- 1 file changed, 6 insertions(+), 1 deletion(-) diff --git a/drivers/net/phy/mdio_bus.c b/drivers/net/phy/mdio_bus.c index 1cd604cd1fa1..16e021b477f0 100644 --- a/drivers/net/phy/mdio_bus.c +++ b/drivers/net/phy/mdio_bus.c @@ -108,7 +108,12 @@ EXPORT_SYMBOL(mdiobus_unregister_device); struct phy_device *mdiobus_get_phy(struct mii_bus *bus, int addr) { - struct mdio_device *mdiodev = bus->mdio_map[addr]; + struct mdio_device *mdiodev; + + if (addr < 0 || addr >= ARRAY_SIZE(bus->mdio_map)) + return NULL; + + mdiodev = bus->mdio_map[addr]; if (!mdiodev) return NULL; -- 2.39.0