Based on kernel version 4.9. Page generated on 2016-12-21 14:36 EST.
1 2 The "environmental" rules for authors of any new tc actions are: 3 4 1) If you stealeth or borroweth any packet thou shalt be branching 5 from the righteous path and thou shalt cloneth. 6 7 For example if your action queues a packet to be processed later, 8 or intentionally branches by redirecting a packet, then you need to 9 clone the packet. 10 11 2) If you munge any packet thou shalt call pskb_expand_head in the case 12 someone else is referencing the skb. After that you "own" the skb. 13 14 3) Dropping packets you don't own is a no-no. You simply return 15 TC_ACT_SHOT to the caller and they will drop it. 16 17 The "environmental" rules for callers of actions (qdiscs etc) are: 18 19 *) Thou art responsible for freeing anything returned as being 20 TC_ACT_SHOT/STOLEN/QUEUED. If none of TC_ACT_SHOT/STOLEN/QUEUED is 21 returned, then all is great and you don't need to do anything. 22 23 Post on netdev if something is unclear.