The fsl_mc_get_endpoint() function uses device_find_child() for localization, which implicitly calls get_device() to increment the device's reference count before returning the pointer. However, the caller dpaa2_eth_connect_mac() fails to properly release this reference in multiple scenarios. We should call put_device() to decrement reference count properly.
As comment of device_find_child() says, 'NOTE: you will need to drop the reference with put_device() after use'.
Found by code review.
Cc: stable@vger.kernel.org Fixes: 719479230893 ("dpaa2-eth: add MAC/PHY support through phylink") Signed-off-by: Ma Ke make24@iscas.ac.cn --- drivers/net/ethernet/freescale/dpaa2/dpaa2-eth.c | 15 ++++++++++++--- 1 file changed, 12 insertions(+), 3 deletions(-)
diff --git a/drivers/net/ethernet/freescale/dpaa2/dpaa2-eth.c b/drivers/net/ethernet/freescale/dpaa2/dpaa2-eth.c index b82f121cadad..0f4efd505332 100644 --- a/drivers/net/ethernet/freescale/dpaa2/dpaa2-eth.c +++ b/drivers/net/ethernet/freescale/dpaa2/dpaa2-eth.c @@ -4666,12 +4666,19 @@ static int dpaa2_eth_connect_mac(struct dpaa2_eth_priv *priv) return PTR_ERR(dpmac_dev); }
- if (IS_ERR(dpmac_dev) || dpmac_dev->dev.type != &fsl_mc_bus_dpmac_type) + if (IS_ERR(dpmac_dev)) return 0;
+ if (dpmac_dev->dev.type != &fsl_mc_bus_dpmac_type) { + err = 0; + goto out_put_device; + } + mac = kzalloc(sizeof(struct dpaa2_mac), GFP_KERNEL); - if (!mac) - return -ENOMEM; + if (!mac) { + err = -ENOMEM; + goto out_put_device; + }
mac->mc_dev = dpmac_dev; mac->mc_io = priv->mc_io; @@ -4705,6 +4712,8 @@ static int dpaa2_eth_connect_mac(struct dpaa2_eth_priv *priv) dpaa2_mac_close(mac); err_free_mac: kfree(mac); +out_put_device: + put_device(&dpmac_dev->dev); return err; }