Re: ppp/pppoe, still panic 4.15.3 in ppp_push

[Guillaume Nault]

On Wed, Feb 14, 2018 at 03:17:23PM +0200, Denys Fedoryshchenko wrote:
> Hi,
> 
> Upgraded kernel to 4.15.3, still it crashes after while (several hours,
> cannot do bisect, as it is production server).
> 
> dev ppp # gdb ppp_generic.o
> GNU gdb (Gentoo 7.12.1 vanilla) 7.12.1
> <<skipped>>
> Reading symbols from ppp_generic.o...done.
> (gdb) list *ppp_push+0x73
> 0x681 is in ppp_push (drivers/net/ppp/ppp_generic.c:1663).
> 1658                  list = list->next;
> 1659                  pch = list_entry(list, struct channel, clist);
> 1660
> 1661                  spin_lock(&pch->downl);
> 1662                  if (pch->chan) {
> 1663                          if (pch->chan->ops->start_xmit(pch->chan, skb))
> 1664                                  ppp->xmit_pending = NULL;
> 1665                  } else {
> 1666                          /* channel got unregistered */
> 1667                          kfree_skb(skb);
> 
> 
I expect a memory corruption. Do you have the possibility to run with
KASAN by any chance?