2021-06-09 15:19:03

by Sander Vanheule

[permalink] [raw]
Subject: [PATCH v2 2/2] regmap: mdio: Reject invalid addresses

When an invalid register offset is provided, the upper bits are silently
discarded. Change this to return -ENXIO instead, to help catch potential
bugs.

Signed-off-by: Sander Vanheule <[email protected]>
---
drivers/base/regmap/regmap-mdio.c | 20 ++++++++++++++++----
1 file changed, 16 insertions(+), 4 deletions(-)

diff --git a/drivers/base/regmap/regmap-mdio.c b/drivers/base/regmap/regmap-mdio.c
index b772b42809e2..6a20201299f5 100644
--- a/drivers/base/regmap/regmap-mdio.c
+++ b/drivers/base/regmap/regmap-mdio.c
@@ -31,14 +31,20 @@ static int regmap_mdio_c22_read(void *context, unsigned int reg, unsigned int *v
{
struct mdio_device *mdio_dev = context;

- return regmap_mdio_read(mdio_dev, reg & REGNUM_C22_MASK, val);
+ if (unlikely(reg & ~REGNUM_C22_MASK))
+ return -ENXIO;
+
+ return regmap_mdio_read(mdio_dev, reg, val);
}

static int regmap_mdio_c22_write(void *context, unsigned int reg, unsigned int val)
{
struct mdio_device *mdio_dev = context;

- return regmap_mdio_write(mdio_dev, reg & REGNUM_C22_MASK, val);
+ if (unlikely(reg & ~REGNUM_C22_MASK))
+ return -ENXIO;
+
+ return mdiobus_write(mdio_dev->bus, mdio_dev->addr, reg, val);
}

static const struct regmap_bus regmap_mdio_c22_bus = {
@@ -50,14 +56,20 @@ static int regmap_mdio_c45_read(void *context, unsigned int reg, unsigned int *v
{
struct mdio_device *mdio_dev = context;

- return regmap_mdio_read(mdio_dev, MII_ADDR_C45 | (reg & REGNUM_C45_MASK), val);
+ if (unlikely(reg & ~REGNUM_C45_MASK))
+ return -ENXIO;
+
+ return regmap_mdio_read(mdio_dev, MII_ADDR_C45 | reg, val);
}

static int regmap_mdio_c45_write(void *context, unsigned int reg, unsigned int val)
{
struct mdio_device *mdio_dev = context;

- return regmap_mdio_write(mdio_dev, MII_ADDR_C45 | (reg & REGNUM_C45_MASK), val);
+ if (unlikely(reg & ~REGNUM_C45_MASK))
+ return -ENXIO;
+
+ return regmap_mdio_write(mdio_dev, MII_ADDR_C45 | reg, val);
}

static const struct regmap_bus regmap_mdio_c45_bus = {
--
2.31.1