netdev - Re: [PATCH 3/5 (resend)] veth: Allow to create peer link with given ifindex

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]

Date:	Tue, 7 Aug 2012 19:36:13 +0100
From:	Ben Hutchings <bhutchings@...arflare.com>
To:	Pavel Emelyanov <xemul@...allels.com>
CC:	David Miller <davem@...emloft.net>,
	Eric Dumazet <eric.dumazet@...il.com>,
	"Eric W. Biederman" <ebiederm@...ssion.com>,
	Linux Netdev List <netdev@...r.kernel.org>
Subject: Re: [PATCH 3/5 (resend)] veth: Allow to create peer link with given
 ifindex

On Tue, 2012-08-07 at 15:02 +0400, Pavel Emelyanov wrote:
> The ifinfomsg is in there (thanks kaber@ for foreseeing this long time ago),
> so take the given ifidex and register netdev with it.
> 
> Signed-off-by: Pavel Emelyanov <xemul@...allels.com>
> ---
>  drivers/net/veth.c |    3 +++
>  1 files changed, 3 insertions(+), 0 deletions(-)
> 
> diff --git a/drivers/net/veth.c b/drivers/net/veth.c
> index 5852361..496c026 100644
> --- a/drivers/net/veth.c
> +++ b/drivers/net/veth.c
> @@ -348,6 +348,9 @@ static int veth_newlink(struct net *src_net, struct net_device *dev,
>  	if (tbp[IFLA_ADDRESS] == NULL)
>  		eth_hw_addr_random(peer);
>  
> +	if (ifmp)
> +		peer->ifindex = ifmp->ifi_index;
> +
>  	err = register_netdevice(peer);
>  	put_net(net);
>  	net = NULL;

Is this safe, given that this code path previously ignored
ifmp->ifi_index?  Userland could be passing in garbage and may now fail
occasionally because the value clashes with an existing interface.

Ben.

-- 
Ben Hutchings, Staff Engineer, Solarflare
Not speaking for my employer; that's the marketing department's job.
They asked us to note that Solarflare product names are trademarked.

--
To unsubscribe from this list: send the line "unsubscribe netdev" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html