the following script: # tc qdisc add dev eth0 clsact # tc filter add dev eth0 egress matchall action mpls pop
implicitly makes the kernel drop all packets transmitted by eth0, if they don't have a MPLS header. This behavior is uncommon: other encapsulations (like VLAN) just let the packet pass unmodified. Since the result of MPLS 'pop' operation would be the same regardless of the presence / absence of MPLS header(s) in the original packet, we can let skb_mpls_pop() return 0 when dealing with non-MPLS packets. Fixes: 2a2ea50870ba ("net: sched: add mpls manipulation actions to TC") Signed-off-by: Davide Caratti <dcara...@redhat.com> --- net/core/skbuff.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/net/core/skbuff.c b/net/core/skbuff.c index 529133611ea2..cd59ccd6da57 100644 --- a/net/core/skbuff.c +++ b/net/core/skbuff.c @@ -5536,7 +5536,7 @@ int skb_mpls_pop(struct sk_buff *skb, __be16 next_proto) int err; if (unlikely(!eth_p_mpls(skb->protocol))) - return -EINVAL; + return 0; err = skb_ensure_writable(skb, skb->mac_len + MPLS_HLEN); if (unlikely(err)) -- 2.21.0