This is a note to let you know that I've just added the patch titled
r6040: Fix kmemleak in probe and remove
to the 6.1-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
r6040-fix-kmemleak-in-probe-and-remove.patch
and it can be found in the queue-6.1 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
commit 87635d83d0092f0d8d477eac9590c6f82c0a139e
Author: Li Zetao <lizetao1@xxxxxxxxxx>
Date: Tue Dec 13 20:56:14 2022 +0800
r6040: Fix kmemleak in probe and remove
[ Upstream commit 7e43039a49c2da45edc1d9d7c9ede4003ab45a5f ]
There is a memory leaks reported by kmemleak:
unreferenced object 0xffff888116111000 (size 2048):
comm "modprobe", pid 817, jiffies 4294759745 (age 76.502s)
hex dump (first 32 bytes):
00 c4 0a 04 81 88 ff ff 08 10 11 16 81 88 ff ff ................
08 10 11 16 81 88 ff ff 00 00 00 00 00 00 00 00 ................
backtrace:
[<ffffffff815bcd82>] kmalloc_trace+0x22/0x60
[<ffffffff827e20ee>] phy_device_create+0x4e/0x90
[<ffffffff827e6072>] get_phy_device+0xd2/0x220
[<ffffffff827e7844>] mdiobus_scan+0xa4/0x2e0
[<ffffffff827e8be2>] __mdiobus_register+0x482/0x8b0
[<ffffffffa01f5d24>] r6040_init_one+0x714/0xd2c [r6040]
...
The problem occurs in probe process as follows:
r6040_init_one:
mdiobus_register
mdiobus_scan <- alloc and register phy_device,
the reference count of phy_device is 3
r6040_mii_probe
phy_connect <- connect to the first phy_device,
so the reference count of the first
phy_device is 4, others are 3
register_netdev <- fault inject succeeded, goto error handling path
// error handling path
err_out_mdio_unregister:
mdiobus_unregister(lp->mii_bus);
err_out_mdio:
mdiobus_free(lp->mii_bus); <- the reference count of the first
phy_device is 1, it is not released
and other phy_devices are released
// similarly, the remove process also has the same problem
The root cause is traced to the phy_device is not disconnected when
removes one r6040 device in r6040_remove_one() or on error handling path
after r6040_mii probed successfully. In r6040_mii_probe(), a net ethernet
device is connected to the first PHY device of mii_bus, in order to
notify the connected driver when the link status changes, which is the
default behavior of the PHY infrastructure to handle everything.
Therefore the phy_device should be disconnected when removes one r6040
device or on error handling path.
Fix it by adding phy_disconnect() when removes one r6040 device or on
error handling path after r6040_mii probed successfully.
Fixes: 3831861b4ad8 ("r6040: implement phylib")
Signed-off-by: Li Zetao <lizetao1@xxxxxxxxxx>
Reviewed-by: Leon Romanovsky <leonro@xxxxxxxxxx>
Link: https://lore.kernel.org/r/20221213125614.927754-1-lizetao1@xxxxxxxxxx
Signed-off-by: Paolo Abeni <pabeni@xxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
diff --git a/drivers/net/ethernet/rdc/r6040.c b/drivers/net/ethernet/rdc/r6040.c
index eecd52ed1ed2..f4d434c379e7 100644
--- a/drivers/net/ethernet/rdc/r6040.c
+++ b/drivers/net/ethernet/rdc/r6040.c
@@ -1159,10 +1159,12 @@ static int r6040_init_one(struct pci_dev *pdev, const struct pci_device_id *ent)
err = register_netdev(dev);
if (err) {
dev_err(&pdev->dev, "Failed to register net device\n");
- goto err_out_mdio_unregister;
+ goto err_out_phy_disconnect;
}
return 0;
+err_out_phy_disconnect:
+ phy_disconnect(dev->phydev);
err_out_mdio_unregister:
mdiobus_unregister(lp->mii_bus);
err_out_mdio:
@@ -1186,6 +1188,7 @@ static void r6040_remove_one(struct pci_dev *pdev)
struct r6040_private *lp = netdev_priv(dev);
unregister_netdev(dev);
+ phy_disconnect(dev->phydev);
mdiobus_unregister(lp->mii_bus);
mdiobus_free(lp->mii_bus);
netif_napi_del(&lp->napi);
