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| author | Zeng Heng <zengheng4@huawei.com> | 2022-12-03 08:34:41 +0100 |
|---|---|---|
| committer | Paolo Abeni <pabeni@redhat.com> | 2022-12-06 12:50:00 +0100 |
| commit | cb37617687f2bfa5b675df7779f869147c9002bd (patch) | |
| tree | 8be74c2b5bf3d32ea6914c932177f3f218397225 /drivers | |
| parent | net: hisilicon: Fix potential use-after-free in hisi_femac_rx() (diff) | |
| download | linux-cb37617687f2bfa5b675df7779f869147c9002bd.tar.xz linux-cb37617687f2bfa5b675df7779f869147c9002bd.zip | |
net: mdio: fix unbalanced fwnode reference count in mdio_device_release()
There is warning report about of_node refcount leak
while probing mdio device:
OF: ERROR: memory leak, expected refcount 1 instead of 2,
of_node_get()/of_node_put() unbalanced - destroy cset entry:
attach overlay node /spi/soc@0/mdio@710700c0/ethernet@4
In of_mdiobus_register_device(), we increase fwnode refcount
by fwnode_handle_get() before associating the of_node with
mdio device, but it has never been decreased in normal path.
Since that, in mdio_device_release(), it needs to call
fwnode_handle_put() in addition instead of calling kfree()
directly.
After above, just calling mdio_device_free() in the error handle
path of of_mdiobus_register_device() is enough to keep the
refcount balanced.
Fixes: a9049e0c513c ("mdio: Add support for mdio drivers.")
Signed-off-by: Zeng Heng <zengheng4@huawei.com>
Reviewed-by: Yang Yingliang <yangyingliang@huawei.com>
Reviewed-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
Link: https://lore.kernel.org/r/20221203073441.3885317-1-zengheng4@huawei.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Diffstat (limited to 'drivers')
| -rw-r--r-- | drivers/net/mdio/of_mdio.c | 3 | ||||
| -rw-r--r-- | drivers/net/phy/mdio_device.c | 2 |
2 files changed, 4 insertions, 1 deletions
diff --git a/drivers/net/mdio/of_mdio.c b/drivers/net/mdio/of_mdio.c index 796e9c7857d0..510822d6d0d9 100644 --- a/drivers/net/mdio/of_mdio.c +++ b/drivers/net/mdio/of_mdio.c @@ -68,8 +68,9 @@ static int of_mdiobus_register_device(struct mii_bus *mdio, /* All data is now stored in the mdiodev struct; register it. */ rc = mdio_device_register(mdiodev); if (rc) { + device_set_node(&mdiodev->dev, NULL); + fwnode_handle_put(fwnode); mdio_device_free(mdiodev); - of_node_put(child); return rc; } diff --git a/drivers/net/phy/mdio_device.c b/drivers/net/phy/mdio_device.c index 250742ffdfd9..044828d081d2 100644 --- a/drivers/net/phy/mdio_device.c +++ b/drivers/net/phy/mdio_device.c @@ -21,6 +21,7 @@ #include <linux/slab.h> #include <linux/string.h> #include <linux/unistd.h> +#include <linux/property.h> void mdio_device_free(struct mdio_device *mdiodev) { @@ -30,6 +31,7 @@ EXPORT_SYMBOL(mdio_device_free); static void mdio_device_release(struct device *dev) { + fwnode_handle_put(dev->fwnode); kfree(to_mdio_device(dev)); } |