9832 Original bug discovered as 9560 has friends IPv4 packets coming in as IPv6 creating chaos
Reviewed by: Robert Mustacchi <rm@joyent.com>

*** 19,29 ****
   * CDDL HEADER END
   */
  
  /*
   * Copyright (c) 2010, Oracle and/or its affiliates. All rights reserved.
!  * Copyright (c) 2015, Joyent, Inc.  All rights reserved.
   */
  /*
   * Copyright 2014 Nexenta Systems, Inc.  All rights reserved.
   */
  
--- 19,29 ----
   * CDDL HEADER END
   */
  
  /*
   * Copyright (c) 2010, Oracle and/or its affiliates. All rights reserved.
!  * Copyright (c) 2019, Joyent, Inc.  All rights reserved.
   */
  /*
   * Copyright 2014 Nexenta Systems, Inc.  All rights reserved.
   */
  
*** 810,822 ****
          boolean_t       first_frag = B_FALSE;
          ip6_frag_t      *frag = NULL;
          uint8_t         proto;
          struct udphdr   *udph;
          uchar_t         *dh;
  
!         if (!mac_ip_hdr_length_v6(ip6h, end, &hdrlen, &proto, &frag))
!                 return (ENOSPC);
  
          if (proto != IPPROTO_UDP)
                  return (EINVAL);
  
          if (frag != NULL) {
--- 810,824 ----
          boolean_t       first_frag = B_FALSE;
          ip6_frag_t      *frag = NULL;
          uint8_t         proto;
          struct udphdr   *udph;
          uchar_t         *dh;
+         int             errno;
  
!         errno = mac_ip_hdr_length_v6(ip6h, end, &hdrlen, &proto, &frag);
!         if (errno != 0)
!                 return (errno);
  
          if (proto != IPPROTO_UDP)
                  return (EINVAL);
  
          if (frag != NULL) {
*** 859,871 ****
          uint16_t                hdrlen;
          ip6_frag_t              *frag = NULL;
          uint8_t                 proto;
          uchar_t                 *hdrp;
          struct icmp6_hdr        *icmp;
  
!         if (!mac_ip_hdr_length_v6(ip6h, end, &hdrlen, &proto, &frag))
!                 return (ENOSPC);
  
          if (proto != IPPROTO_ICMPV6)
                  return (EINVAL);
  
          if (frag != NULL) {
--- 861,875 ----
          uint16_t                hdrlen;
          ip6_frag_t              *frag = NULL;
          uint8_t                 proto;
          uchar_t                 *hdrp;
          struct icmp6_hdr        *icmp;
+         int                     errno;
  
!         errno = mac_ip_hdr_length_v6(ip6h, end, &hdrlen, &proto, &frag);
!         if (errno != 0)
!                 return (errno);
  
          if (proto != IPPROTO_ICMPV6)
                  return (EINVAL);
  
          if (frag != NULL) {