1. Patchew
  2. linux
  3. View series

[PATCH] net: renesas: rswitch: Fix memory leak in rswitch_phy_device_init()

Ma Ke posted 1 patch 1 week ago 
drivers/net/ethernet/renesas/rswitch_main.c | 12 ++++++++----
1 file changed, 8 insertions(+), 4 deletions(-)
[PATCH] net: renesas: rswitch: Fix memory leak in rswitch_phy_device_init()
Posted by Ma Ke 1 week ago 
rswitch_phy_device_init() calls of_phy_find_device(), which calls
bus_find_device() to increments the refcount of the returned device.
The current implementation does not decrement the refcount after the
reference is no longer needed, causing a memory leak.

Add phy_device_free() to release the reference via put_device() and
balance the refcount.

Found by code review.

Signed-off-by: Ma Ke <make24@iscas.ac.cn>
Cc: stable@vger.kernel.org
Fixes: 0df024d0f1d3 ("net: renesas: rswitch: Add host_interfaces setting")
---
 drivers/net/ethernet/renesas/rswitch_main.c | 12 ++++++++----
 1 file changed, 8 insertions(+), 4 deletions(-)

diff --git a/drivers/net/ethernet/renesas/rswitch_main.c b/drivers/net/ethernet/renesas/rswitch_main.c
index 6fe964816322..126da0371a19 100644
--- a/drivers/net/ethernet/renesas/rswitch_main.c
+++ b/drivers/net/ethernet/renesas/rswitch_main.c
@@ -1459,7 +1459,7 @@ static void rswitch_phy_remove_link_mode(struct rswitch_device *rdev,
 
 static int rswitch_phy_device_init(struct rswitch_device *rdev)
 {
-	struct phy_device *phydev;
+	struct phy_device *phydev, *tmp_phydev;
 	struct device_node *phy;
 	int err = -ENOENT;
 
@@ -1473,14 +1473,18 @@ static int rswitch_phy_device_init(struct rswitch_device *rdev)
 	/* Set phydev->host_interfaces before calling of_phy_connect() to
 	 * configure the PHY with the information of host_interfaces.
 	 */
-	phydev = of_phy_find_device(phy);
-	if (!phydev)
+	tmp_phydev = of_phy_find_device(phy);
+	if (!tmp_phydev)
 		goto out;
-	__set_bit(rdev->etha->phy_interface, phydev->host_interfaces);
+	__set_bit(rdev->etha->phy_interface, tmp_phydev->host_interfaces);
 	phydev->mac_managed_pm = true;
 
 	phydev = of_phy_connect(rdev->ndev, phy, rswitch_adjust_link, 0,
 				rdev->etha->phy_interface);
+
+	/* Release the temporary reference obtained by of_phy_find_device() */
+	phy_device_free(tmp_phydev);
+
 	if (!phydev)
 		goto out;
 
-- 
2.43.0
Re: [PATCH] net: renesas: rswitch: Fix memory leak in rswitch_phy_device_init()
Posted by kernel test robot 6 days, 11 hours ago 
Hi Ma,

kernel test robot noticed the following build warnings:

[auto build test WARNING on net-next/main]
[also build test WARNING on net/main linus/master v7.0-rc6 next-20260327]
[If your patch is applied to the wrong git tree, kindly drop us a note.
And when submitting patch, we suggest to use '--base' as documented in
https://git-scm.com/docs/git-format-patch#_base_tree_information]

url:    https://github.com/intel-lab-lkp/linux/commits/Ma-Ke/net-renesas-rswitch-Fix-memory-leak-in-rswitch_phy_device_init/20260330-214200
base:   net-next/main
patch link:    https://lore.kernel.org/r/20260330073541.2871414-1-make24%40iscas.ac.cn
patch subject: [PATCH] net: renesas: rswitch: Fix memory leak in rswitch_phy_device_init()
config: hexagon-allmodconfig (https://download.01.org/0day-ci/archive/20260331/202603310514.S572gcNU-lkp@intel.com/config)
compiler: clang version 17.0.6 (https://github.com/llvm/llvm-project 6009708b4367171ccdbf4b5905cb6a803753fe18)
reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20260331/202603310514.S572gcNU-lkp@intel.com/reproduce)

If you fix the issue in a separate patch/commit (i.e. not just a new version of
the same patch/commit), kindly add following tags
| Reported-by: kernel test robot <lkp@intel.com>
| Closes: https://lore.kernel.org/oe-kbuild-all/202603310514.S572gcNU-lkp@intel.com/

All warnings (new ones prefixed by >>):

>> drivers/net/ethernet/renesas/rswitch_main.c:1480:2: warning: variable 'phydev' is uninitialized when used here [-Wuninitialized]
    1480 |         phydev->mac_managed_pm = true;
         |         ^~~~~~
   drivers/net/ethernet/renesas/rswitch_main.c:1462:27: note: initialize the variable 'phydev' to silence this warning
    1462 |         struct phy_device *phydev, *tmp_phydev;
         |                                  ^
         |                                   = NULL
   1 warning generated.


vim +/phydev +1480 drivers/net/ethernet/renesas/rswitch_main.c

3590918b5d07aa drivers/net/ethernet/renesas/rswitch.c      Yoshihiro Shimoda 2022-10-31  1459  
c16a5033f77b9e drivers/net/ethernet/renesas/rswitch.c      Yoshihiro Shimoda 2023-02-01  1460  static int rswitch_phy_device_init(struct rswitch_device *rdev)
3590918b5d07aa drivers/net/ethernet/renesas/rswitch.c      Yoshihiro Shimoda 2022-10-31  1461  {
142f4caaa41b9c drivers/net/ethernet/renesas/rswitch_main.c Ma Ke             2026-03-30  1462  	struct phy_device *phydev, *tmp_phydev;
c16a5033f77b9e drivers/net/ethernet/renesas/rswitch.c      Yoshihiro Shimoda 2023-02-01  1463  	struct device_node *phy;
0df024d0f1d3e5 drivers/net/ethernet/renesas/rswitch.c      Yoshihiro Shimoda 2023-02-01  1464  	int err = -ENOENT;
3590918b5d07aa drivers/net/ethernet/renesas/rswitch.c      Yoshihiro Shimoda 2022-10-31  1465  
b46f1e5793298c drivers/net/ethernet/renesas/rswitch.c      Yoshihiro Shimoda 2023-02-01  1466  	if (!rdev->np_port)
3590918b5d07aa drivers/net/ethernet/renesas/rswitch.c      Yoshihiro Shimoda 2022-10-31  1467  		return -ENODEV;
3590918b5d07aa drivers/net/ethernet/renesas/rswitch.c      Yoshihiro Shimoda 2022-10-31  1468  
c16a5033f77b9e drivers/net/ethernet/renesas/rswitch.c      Yoshihiro Shimoda 2023-02-01  1469  	phy = of_parse_phandle(rdev->np_port, "phy-handle", 0);
c16a5033f77b9e drivers/net/ethernet/renesas/rswitch.c      Yoshihiro Shimoda 2023-02-01  1470  	if (!phy)
c16a5033f77b9e drivers/net/ethernet/renesas/rswitch.c      Yoshihiro Shimoda 2023-02-01  1471  		return -ENODEV;
c16a5033f77b9e drivers/net/ethernet/renesas/rswitch.c      Yoshihiro Shimoda 2023-02-01  1472  
0df024d0f1d3e5 drivers/net/ethernet/renesas/rswitch.c      Yoshihiro Shimoda 2023-02-01  1473  	/* Set phydev->host_interfaces before calling of_phy_connect() to
0df024d0f1d3e5 drivers/net/ethernet/renesas/rswitch.c      Yoshihiro Shimoda 2023-02-01  1474  	 * configure the PHY with the information of host_interfaces.
0df024d0f1d3e5 drivers/net/ethernet/renesas/rswitch.c      Yoshihiro Shimoda 2023-02-01  1475  	 */
142f4caaa41b9c drivers/net/ethernet/renesas/rswitch_main.c Ma Ke             2026-03-30  1476  	tmp_phydev = of_phy_find_device(phy);
142f4caaa41b9c drivers/net/ethernet/renesas/rswitch_main.c Ma Ke             2026-03-30  1477  	if (!tmp_phydev)
0df024d0f1d3e5 drivers/net/ethernet/renesas/rswitch.c      Yoshihiro Shimoda 2023-02-01  1478  		goto out;
142f4caaa41b9c drivers/net/ethernet/renesas/rswitch_main.c Ma Ke             2026-03-30  1479  	__set_bit(rdev->etha->phy_interface, tmp_phydev->host_interfaces);
35b78409e1c7ff drivers/net/ethernet/renesas/rswitch.c      Yoshihiro Shimoda 2023-10-17 @1480  	phydev->mac_managed_pm = true;
0df024d0f1d3e5 drivers/net/ethernet/renesas/rswitch.c      Yoshihiro Shimoda 2023-02-01  1481  
c16a5033f77b9e drivers/net/ethernet/renesas/rswitch.c      Yoshihiro Shimoda 2023-02-01  1482  	phydev = of_phy_connect(rdev->ndev, phy, rswitch_adjust_link, 0,
c16a5033f77b9e drivers/net/ethernet/renesas/rswitch.c      Yoshihiro Shimoda 2023-02-01  1483  				rdev->etha->phy_interface);
142f4caaa41b9c drivers/net/ethernet/renesas/rswitch_main.c Ma Ke             2026-03-30  1484  
142f4caaa41b9c drivers/net/ethernet/renesas/rswitch_main.c Ma Ke             2026-03-30  1485  	/* Release the temporary reference obtained by of_phy_find_device() */
142f4caaa41b9c drivers/net/ethernet/renesas/rswitch_main.c Ma Ke             2026-03-30  1486  	phy_device_free(tmp_phydev);
142f4caaa41b9c drivers/net/ethernet/renesas/rswitch_main.c Ma Ke             2026-03-30  1487  
c16a5033f77b9e drivers/net/ethernet/renesas/rswitch.c      Yoshihiro Shimoda 2023-02-01  1488  	if (!phydev)
0df024d0f1d3e5 drivers/net/ethernet/renesas/rswitch.c      Yoshihiro Shimoda 2023-02-01  1489  		goto out;
3590918b5d07aa drivers/net/ethernet/renesas/rswitch.c      Yoshihiro Shimoda 2022-10-31  1490  
c16a5033f77b9e drivers/net/ethernet/renesas/rswitch.c      Yoshihiro Shimoda 2023-02-01  1491  	phy_set_max_speed(phydev, SPEED_2500);
c16a5033f77b9e drivers/net/ethernet/renesas/rswitch.c      Yoshihiro Shimoda 2023-02-01  1492  	phy_remove_link_mode(phydev, ETHTOOL_LINK_MODE_10baseT_Half_BIT);
c16a5033f77b9e drivers/net/ethernet/renesas/rswitch.c      Yoshihiro Shimoda 2023-02-01  1493  	phy_remove_link_mode(phydev, ETHTOOL_LINK_MODE_10baseT_Full_BIT);
c16a5033f77b9e drivers/net/ethernet/renesas/rswitch.c      Yoshihiro Shimoda 2023-02-01  1494  	phy_remove_link_mode(phydev, ETHTOOL_LINK_MODE_100baseT_Half_BIT);
c16a5033f77b9e drivers/net/ethernet/renesas/rswitch.c      Yoshihiro Shimoda 2023-02-01  1495  	phy_remove_link_mode(phydev, ETHTOOL_LINK_MODE_1000baseT_Half_BIT);
c16a5033f77b9e drivers/net/ethernet/renesas/rswitch.c      Yoshihiro Shimoda 2023-02-01  1496  	rswitch_phy_remove_link_mode(rdev, phydev);
3590918b5d07aa drivers/net/ethernet/renesas/rswitch.c      Yoshihiro Shimoda 2022-10-31  1497  
c16a5033f77b9e drivers/net/ethernet/renesas/rswitch.c      Yoshihiro Shimoda 2023-02-01  1498  	phy_attached_info(phydev);
3590918b5d07aa drivers/net/ethernet/renesas/rswitch.c      Yoshihiro Shimoda 2022-10-31  1499  
0df024d0f1d3e5 drivers/net/ethernet/renesas/rswitch.c      Yoshihiro Shimoda 2023-02-01  1500  	err = 0;
0df024d0f1d3e5 drivers/net/ethernet/renesas/rswitch.c      Yoshihiro Shimoda 2023-02-01  1501  out:
0df024d0f1d3e5 drivers/net/ethernet/renesas/rswitch.c      Yoshihiro Shimoda 2023-02-01  1502  	of_node_put(phy);
0df024d0f1d3e5 drivers/net/ethernet/renesas/rswitch.c      Yoshihiro Shimoda 2023-02-01  1503  
0df024d0f1d3e5 drivers/net/ethernet/renesas/rswitch.c      Yoshihiro Shimoda 2023-02-01  1504  	return err;
3590918b5d07aa drivers/net/ethernet/renesas/rswitch.c      Yoshihiro Shimoda 2022-10-31  1505  }
3590918b5d07aa drivers/net/ethernet/renesas/rswitch.c      Yoshihiro Shimoda 2022-10-31  1506  

-- 
0-DAY CI Kernel Test Service
https://github.com/intel/lkp-tests/wiki
Re: [PATCH] net: renesas: rswitch: Fix memory leak in rswitch_phy_device_init()
Posted by Nikita Yushchenko 1 week ago 
> -	phydev = of_phy_find_device(phy);
> -	if (!phydev)
> +	tmp_phydev = of_phy_find_device(phy);
> +	if (!tmp_phydev)
>   		goto out;
> -	__set_bit(rdev->etha->phy_interface, phydev->host_interfaces);
> +	__set_bit(rdev->etha->phy_interface, tmp_phydev->host_interfaces);
>   	phydev->mac_managed_pm = true;

shall be tmp_phydev ?

Patchew 2.1-devel-ea86937

© 2016 - 2026 Red Hat, Inc.