netdev - Re: lan78xx and phy_state

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite for Android: free password hash cracker in your pocket

[<prev] [next>] [<thread-prev] [day] [month] [year] [list]

Message-ID: <20191016153646.GG17013@lunn.ch>
Date:   Wed, 16 Oct 2019 17:36:46 +0200
From:   Andrew Lunn <andrew@...n.ch>
To:     Russell King - ARM Linux admin <linux@...linux.org.uk>
Cc:     Heiner Kallweit <hkallweit1@...il.com>,
        Woojung Huh <woojung.huh@...rochip.com>,
        Microchip Linux Driver Support <UNGLinuxDriver@...rochip.com>,
        Florian Fainelli <f.fainelli@...il.com>,
        Daniel Wagner <dwagner@...e.de>, netdev@...r.kernel.org,
        bcm-kernel-feedback-list@...adcom.com,
        Stefan Wahren <wahrenst@....net>,
        linux-arm-kernel@...ts.infradead.org,
        linux-rpi-kernel@...ts.infradead.org
Subject: Re: lan78xx and phy_state_machine

> > - lan78xx_phy_init() (incl. the call to phy_connect_direct()) is called
> >   after register_netdev(). This may cause races.
> 
> That isn't a problem.  We have lots of network device drivers that do
> this - in their open() function.

Hi Russell

Actually, here is it. lan7801_phy_init() finds the PHY device and
connects it to the MAC. lan78xx_open() calls phy_start(), with the
assumption lan7801_phy_init() has been called.

But the stack trace just provided shows this assumption is wrong. As
soon a register_netdev() is called, the kernel auto configuration is
kicking in and opening the device.

lan78xx_phy_init() needs to happen before register_netdev(), or inside
lan78xx_open().

	Andrew