netdev - Re: [PATCH net] igb: fix deadlock caused by taking RTNL in RPM resume path

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: Windows password security audit tool. GUI, reports in PDF.

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

Message-ID: <20211129171712.500e37cb@kicinski-fedora-pc1c0hjn.dhcp.thefacebook.com>
Date:   Mon, 29 Nov 2021 17:17:12 -0800
From:   Jakub Kicinski <kuba@...nel.org>
To:     Heiner Kallweit <hkallweit1@...il.com>
Cc:     David Miller <davem@...emloft.net>,
        Jesse Brandeburg <jesse.brandeburg@...el.com>,
        Tony Nguyen <anthony.l.nguyen@...el.com>,
        "netdev@...r.kernel.org" <netdev@...r.kernel.org>,
        intel-wired-lan <intel-wired-lan@...ts.osuosl.org>
Subject: Re: [PATCH net] igb: fix deadlock caused by taking RTNL in RPM
 resume path

On Mon, 29 Nov 2021 22:14:06 +0100 Heiner Kallweit wrote:
> -	rtnl_lock();
> +	if (!rpm)
> +		rtnl_lock();

Is there an ASSERT_RTNL() hidden in any of the below? Can we add one?
Unless we're 100% confident nobody will RPM resume without rtnl held..

>  	if (!err && netif_running(netdev))
>  		err = __igb_open(netdev, true);
>  
>  	if (!err)
>  		netif_device_attach(netdev);
> -	rtnl_unlock();
> +	if (!rpm)
> +		rtnl_unlock();