This is a note to let you know that I've just added the patch titled net: phylink: don't call netif_carrier_off() with NULL netdev to the 5.14-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: net-phylink-don-t-call-netif_carrier_off-with-null-n.patch and it can be found in the queue-5.14 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. commit 9fb763e760d24cd445ba1036486ca27ce2c19140 Author: Russell King (Oracle) <rmk+kernel@xxxxxxxxxxxxxxx> Date: Fri Sep 17 14:36:31 2021 +0100 net: phylink: don't call netif_carrier_off() with NULL netdev [ Upstream commit cbcca2e3961eac736566ac13ef0d0bf6f0b764ec ] Dan Carpenter points out that we have a code path that permits a NULL netdev pointer to be passed to netif_carrier_off(), which will cause a kernel oops. In any case, we need to set pl->old_link_state to false to have the desired effect when there is no netdev present. Fixes: f97493657c63 ("net: phylink: add suspend/resume support") Reported-by: Dan Carpenter <dan.carpenter@xxxxxxxxxx> Signed-off-by: Russell King (Oracle) <rmk+kernel@xxxxxxxxxxxxxxx> Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> diff --git a/drivers/net/phy/phylink.c b/drivers/net/phy/phylink.c index 0d3d9c3ee83c8..6e96d7b7ee445 100644 --- a/drivers/net/phy/phylink.c +++ b/drivers/net/phy/phylink.c @@ -1332,7 +1332,10 @@ void phylink_suspend(struct phylink *pl, bool mac_wol) * but one would hope all packets have been sent. This * also means phylink_resolve() will do nothing. */ - netif_carrier_off(pl->netdev); + if (pl->netdev) + netif_carrier_off(pl->netdev); + else + pl->old_link_state = false; /* We do not call mac_link_down() here as we want the * link to remain up to receive the WoL packets.