diff options
| author | Wei Fang <wei.fang@nxp.com> | 2025-05-23 16:37:59 +0800 |
|---|---|---|
| committer | Jakub Kicinski <kuba@kernel.org> | 2025-05-27 17:10:25 -0700 |
| commit | 0795b05a59b1371b18ffbf09d385296b12e9f5d5 (patch) | |
| tree | a7f7ec949443bc2647d99183b95aa9748dc3682a | |
| parent | d8d85ef0a631df9127f202e6371bb33a0b589952 (diff) | |
net: phy: clear phydev->devlink when the link is deleted
There is a potential crash issue when disabling and re-enabling the
network port. When disabling the network port, phy_detach() calls
device_link_del() to remove the device link, but it does not clear
phydev->devlink, so phydev->devlink is not a NULL pointer. Then the
network port is re-enabled, but if phy_attach_direct() fails before
calling device_link_add(), the code jumps to the "error" label and
calls phy_detach(). Since phydev->devlink retains the old value from
the previous attach/detach cycle, device_link_del() uses the old value,
which accesses a NULL pointer and causes a crash. The simplified crash
log is as follows.
[ 24.702421] Call trace:
[ 24.704856] device_link_put_kref+0x20/0x120
[ 24.709124] device_link_del+0x30/0x48
[ 24.712864] phy_detach+0x24/0x168
[ 24.716261] phy_attach_direct+0x168/0x3a4
[ 24.720352] phylink_fwnode_phy_connect+0xc8/0x14c
[ 24.725140] phylink_of_phy_connect+0x1c/0x34
Therefore, phydev->devlink needs to be cleared when the device link is
deleted.
Fixes: bc66fa87d4fd ("net: phy: Add link between phy dev and mac dev")
Signed-off-by: Wei Fang <wei.fang@nxp.com>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Reviewed-by: Florian Fainelli <florian.fainelli@broadcom.com>
Link: https://patch.msgid.link/20250523083759.3741168-1-wei.fang@nxp.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
| -rw-r--r-- | drivers/net/phy/phy_device.c | 4 |
1 files changed, 3 insertions, 1 deletions
diff --git a/drivers/net/phy/phy_device.c b/drivers/net/phy/phy_device.c index cc1bfd22fb81..7d5e76a3db0e 100644 --- a/drivers/net/phy/phy_device.c +++ b/drivers/net/phy/phy_device.c @@ -1727,8 +1727,10 @@ void phy_detach(struct phy_device *phydev) struct module *ndev_owner = NULL; struct mii_bus *bus; - if (phydev->devlink) + if (phydev->devlink) { device_link_del(phydev->devlink); + phydev->devlink = NULL; + } if (phydev->sysfs_links) { if (dev) |