[Openswan Users] klips_error:ipsec_xmit_encap_once: tried to skb_put 20, 16 available. This should never happen, please report.

[Paul Wouters]

On Sat, 2 Oct 2010, Danilo Godec wrote:

> I have a server running OpenSwan 2.6.29, using MAST stack. The server
> has three Xen VM's and currently 4 active LAN's behind. There is not a
> lot of traffic yet, as the building is not quite finished...
>
> If I connect to a VM and run a simple 'ls -lR /' it will sometimes get
> 'stuck'. At that moment, a lot of these messages appear on the IPSEC server:
>
>> Oct  2 14:04:34 lmqxen1 kernel: [59061.763064]
>> klips_error:ipsec_xmit_encap_once: tried to skb_put 21, 17 available.
>> This should never happen, please report.

Are you running tight on memory?

> I also see these messages when 'cfagent' (a part of 'cfengine') on a VM
> copies files from the server and gets stuck...

Yeah, this does not seem to be an openswan bug. The code in question is:
(one instance of it):

         /* Set the data pointer */
         skb_reserve(n,skb->data-skb->head+headroom);
         /* Set the tail pointer and length */
         if(skb_tailroom(n) < skb->len) {
                 printk(KERN_WARNING "klips_error:skb_copy_expand: "
                        "tried to skb_put %ld, %d available.  This should never happen, please report.\n",
                        (unsigned long int)skb->len,
                        skb_tailroom(n));
                 ipsec_kfree_skb(n);
                 return NULL;
         }

I would check with the xen people to see what might be going on.

Paul