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Subject: Re: [PATCH net v3 2/2] net: avoid infinite loop in mpls_gso_segment
 when mpls_hlen == 0
To:     Balazs Nemeth <bnemeth@redhat.com>, netdev@vger.kernel.org
Cc:     linux-kernel@vger.kernel.org, mst@redhat.com, jasowang@redhat.com,
        davem@davemloft.net, willemb@google.com,
        virtualization@lists.linux-foundation.org
References: <cover.1615288658.git.bnemeth@redhat.com>
 <9b79f43d2dfec8b2cb8e896b5591e7b1c3cc1f6c.1615288658.git.bnemeth@redhat.com>
From:   David Ahern <dsahern@gmail.com>
Message-ID: <0c2f075e-ea66-66df-82e4-2c5fa71b2d43@gmail.com>
Date:   Tue, 9 Mar 2021 08:55:42 -0700
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On 3/9/21 4:31 AM, Balazs Nemeth wrote:
> A packet with skb_inner_network_header(skb) == skb_network_header(skb)
> and ETH_P_MPLS_UC will prevent mpls_gso_segment from pulling any headers
> from the packet. Subsequently, the call to skb_mac_gso_segment will
> again call mpls_gso_segment with the same packet leading to an infinite
> loop. In addition, ensure that the header length is a multiple of four,
> which should hold irrespective of the number of stacked labels.
> 
> Signed-off-by: Balazs Nemeth <bnemeth@redhat.com>
> ---
>  net/mpls/mpls_gso.c | 3 +++
>  1 file changed, 3 insertions(+)
> 


Reviewed-by: David Ahern <dsahern@kernel.org>