net: linkwatch: add check for netdevice being present to linkwatch_do_dev
When bringing down the netdevice (incl. detaching it) and calling netif_carrier_off directly or indirectly the latter triggers an asynchronous linkwatch event. This linkwatch event eventually may fail to access chip registers in the ndo_get_stats/ndo_get_stats64 callback because the device isn't accessible any longer, see call trace in [0]. To prevent this scenario don't check for IFF_UP only, but also make sure that the netdevice is present. [0] https://lists.openwall.net/netdev/2018/03/15/62 Signed-off-by:Heiner Kallweit <hkallweit1@gmail.com> Tested-by:
Geert Uytterhoeven <geert+renesas@glider.be> Reviewed-by:
Florian Fainelli <f.fainelli@gmail.com> Signed-off-by:
David S. Miller <davem@davemloft.net>
parent
822143ac
Please register or sign in to comment