From mboxrd@z Thu Jan  1 00:00:00 1970
From: David Miller <davem@davemloft.net>
Subject: Re: [PATCH net v2] rtnetlink: Disallow FDB configuration for
 non-Ethernet device
Date: Mon, 29 Oct 2018 20:53:29 -0700 (PDT)
Message-ID: <20181029.205329.2193085560727068930.davem@davemloft.net>
References: <20181029203622.20608-1-idosch@mellanox.com>
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Cc: netdev@vger.kernel.org, vyasevich@gmail.com, dsahern@gmail.com
To: idosch@mellanox.com
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From: Ido Schimmel <idosch@mellanox.com>
Date: Mon, 29 Oct 2018 20:36:43 +0000

> When an FDB entry is configured, the address is validated to have the
> length of an Ethernet address, but the device for which the address is
> configured can be of any type.
> 
> The above can result in the use of uninitialized memory when the address
> is later compared against existing addresses since 'dev->addr_len' is
> used and it may be greater than ETH_ALEN, as with ip6tnl devices.
> 
> Fix this by making sure that FDB entries are only configured for
> Ethernet devices.
 ...
> v2:
> * Make error message more specific (David)
> 
> Fixes: 090096bf3db1 ("net: generic fdb support for drivers without ndo_fdb_<op>")
> Signed-off-by: Ido Schimmel <idosch@mellanox.com>
> Reported-and-tested-by: syzbot+3a288d5f5530b901310e@syzkaller.appspotmail.com
> Reported-and-tested-by: syzbot+d53ab4e92a1db04110ff@syzkaller.appspotmail.com
> Cc: Vlad Yasevich <vyasevich@gmail.com>
> Cc: David Ahern <dsahern@gmail.com>

Applied and queued up for -stable, thanks.