Re: [PATCH net] net/sched: act_mpls: ensure LSE is pullable before reading it

[Marcelo Ricardo Leitner]

On Wed, Nov 18, 2020 at 05:36:52PM +0100, Davide Caratti wrote:

Hi,

>       case TCA_MPLS_ACT_MODIFY:
> +             if (!pskb_may_pull(skb,
> +                                skb_network_offset(skb) + sizeof(new_lse)))
> +                     goto drop;
>               new_lse = tcf_mpls_get_lse(mpls_hdr(skb), p, false);
>               if (skb_mpls_update_lse(skb, new_lse))
>                       goto drop;

Seems TCA_MPLS_ACT_DEC_TTL is also affected. skb_mpls_dec_ttl() will
also call mpls_hdr(skb) without this check.

  Marcelo