netdev - RE: [EXTERNAL] [PATCH] hv_netvsc: Set VF priv_flags to IFF_NO_ADDRCONF before open to prevent IPv6 addrconf

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:
 <SN6PR2101MB09432681A39CCFACE2689BEBCA48A@SN6PR2101MB0943.namprd21.prod.outlook.com>
Date: Thu, 10 Jul 2025 20:24:26 +0000
From: Haiyang Zhang <haiyangz@...rosoft.com>
To: Li Tian <litian@...hat.com>, "netdev@...r.kernel.org"
	<netdev@...r.kernel.org>, "linux-hyperv@...r.kernel.org"
	<linux-hyperv@...r.kernel.org>, Long Li <longli@...rosoft.com>
CC: "linux-kernel@...r.kernel.org" <linux-kernel@...r.kernel.org>, Dexuan Cui
	<decui@...rosoft.com>
Subject: RE: [EXTERNAL] [PATCH] hv_netvsc: Set VF priv_flags to
 IFF_NO_ADDRCONF before open  to prevent IPv6 addrconf



> -----Original Message-----
> From: Li Tian <litian@...hat.com>
> Sent: Wednesday, July 9, 2025 10:46 PM
> To: netdev@...r.kernel.org; linux-hyperv@...r.kernel.org
> Cc: linux-kernel@...r.kernel.org; Haiyang Zhang <haiyangz@...rosoft.com>;
> Dexuan Cui <decui@...rosoft.com>
> Subject: [EXTERNAL] [PATCH] hv_netvsc: Set VF priv_flags to
> IFF_NO_ADDRCONF before open to prevent IPv6 addrconf
> 
> The use of the IFF_SLAVE flag was replaced by IFF_NO_ADDRCONF to
> prevent ipv6 addrconf.
> 
> Commit 8a321cf7becc6c065ae595b837b826a2a81036b9
> ("net: add IFF_NO_ADDRCONF and use it in bonding to prevent ipv6
> addrconf")
> 
> This new flag change was not made to hv_netvsc resulting in the VF being
> assinged an IPv6.
> 
> Suggested-by: Cathy Avery <cavery@...hat.com>
> 
> Signed-off-by: Li Tian <litian@...hat.com>
> ---
>  drivers/net/hyperv/netvsc_drv.c | 4 ++--
>  1 file changed, 2 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/net/hyperv/netvsc_drv.c
> b/drivers/net/hyperv/netvsc_drv.c
> index c41a025c66f0..a31521f00681 100644
> --- a/drivers/net/hyperv/netvsc_drv.c
> +++ b/drivers/net/hyperv/netvsc_drv.c
> @@ -2317,8 +2317,8 @@ static int netvsc_prepare_bonding(struct net_device
> *vf_netdev)
>  	if (!ndev)
>  		return NOTIFY_DONE;
> 
> -	/* set slave flag before open to prevent IPv6 addrconf */
> -	vf_netdev->flags |= IFF_SLAVE;
> +	/* Set no addrconf flag before open to prevent IPv6 addrconf */
> +	vf_netdev->priv_flags |= IFF_NO_ADDRCONF;

The IFF_SLAVE flag is still needed for our user mode, and udev rules to work. 
So please keep it. (you may update the comment though).

cc: Long Li <longli@...rosoft.com>
@Long Li

Thanks,
- Haiyang