From mboxrd@z Thu Jan  1 00:00:00 1970
From: Ido Schimmel <idosch@idosch.org>
Subject: Re: [PATCH net] rtnetlink: ndo_dflt_fdb_dump() only work for
 ARPHRD_ETHER devices
Date: Tue, 4 Dec 2018 19:49:11 +0200
Message-ID: <20181204174911.GA22758@splinter>
References: <20181204174035.107587-1-edumazet@google.com>
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Cc: "David S . Miller" <davem@davemloft.net>,
        netdev <netdev@vger.kernel.org>,
        Eric Dumazet <eric.dumazet@gmail.com>,
        John Fastabend <john.fastabend@gmail.com>,
        Ido Schimmel <idosch@mellanox.com>,
        David Ahern <dsahern@gmail.com>
To: Eric Dumazet <edumazet@google.com>
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On Tue, Dec 04, 2018 at 09:40:35AM -0800, Eric Dumazet wrote:
> kmsan was able to trigger a kernel-infoleak using a gre device [1]
> 
> nlmsg_populate_fdb_fill() has a hard coded assumption
> that dev->addr_len is ETH_ALEN, as normally guaranteed
> for ARPHRD_ETHER devices.
> 
> A similar issue was fixed recently in commit da71577545a5
> ("rtnetlink: Disallow FDB configuration for non-Ethernet device")

...

> Fixes: d83b06036048 ("net: add fdb generic dump routine")
> Signed-off-by: Eric Dumazet <edumazet@google.com>
> Cc: John Fastabend <john.fastabend@gmail.com>
> Cc: Ido Schimmel <idosch@mellanox.com>
> Cc: David Ahern <dsahern@gmail.com>

Reviewed-by: Ido Schimmel <idosch@mellanox.com>

Thanks!