From 3e41d04e2b7373490977d7145fb12109f23cde9c Mon Sep 17 00:00:00 2001 From: Alex Marginean Date: Thu, 16 Jan 2020 19:46:28 +0200 Subject: [PATCH] net: phy: don't crash in phy_read/_write_mmd without a PHY driver The APIs can be used by Ethernet drivers without actually loading a PHY driver. This may become more widespread in the future with 802.3z compatible MAC PCS devices being locally driven by the MAC driver when configuring for a PHY mode with in-band negotiation. Check that drv is not NULL before reading from it. Signed-off-by: Alex Marginean Signed-off-by: Vladimir Oltean Signed-off-by: David S. Miller --- drivers/net/phy/phy-core.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/drivers/net/phy/phy-core.c b/drivers/net/phy/phy-core.c index 769a076514b0..a4d2d59fceca 100644 --- a/drivers/net/phy/phy-core.c +++ b/drivers/net/phy/phy-core.c @@ -387,7 +387,7 @@ int __phy_read_mmd(struct phy_device *phydev, int devad, u32 regnum) if (regnum > (u16)~0 || devad > 32) return -EINVAL; - if (phydev->drv->read_mmd) { + if (phydev->drv && phydev->drv->read_mmd) { val = phydev->drv->read_mmd(phydev, devad, regnum); } else if (phydev->is_c45) { u32 addr = MII_ADDR_C45 | (devad << 16) | (regnum & 0xffff); @@ -444,7 +444,7 @@ int __phy_write_mmd(struct phy_device *phydev, int devad, u32 regnum, u16 val) if (regnum > (u16)~0 || devad > 32) return -EINVAL; - if (phydev->drv->write_mmd) { + if (phydev->drv && phydev->drv->write_mmd) { ret = phydev->drv->write_mmd(phydev, devad, regnum, val); } else if (phydev->is_c45) { u32 addr = MII_ADDR_C45 | (devad << 16) | (regnum & 0xffff); -- 2.11.0