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

@@ -19,11 +19,11 @@
  * CDDL HEADER END
  */
 
 /*
  * Copyright (c) 2010, Oracle and/or its affiliates. All rights reserved.
- * Copyright (c) 2015, Joyent, Inc.  All rights reserved.
+ * Copyright (c) 2019, Joyent, Inc.  All rights reserved.
  */
 /*
  * Copyright 2014 Nexenta Systems, Inc.  All rights reserved.
  */
 

@@ -810,13 +810,15 @@
         boolean_t       first_frag = B_FALSE;
         ip6_frag_t      *frag = NULL;
         uint8_t         proto;
         struct udphdr   *udph;
         uchar_t         *dh;
+        int             errno;
 
-        if (!mac_ip_hdr_length_v6(ip6h, end, &hdrlen, &proto, &frag))
-                return (ENOSPC);
+        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) {

@@ -859,13 +861,15 @@
         uint16_t                hdrlen;
         ip6_frag_t              *frag = NULL;
         uint8_t                 proto;
         uchar_t                 *hdrp;
         struct icmp6_hdr        *icmp;
+        int                     errno;
 
-        if (!mac_ip_hdr_length_v6(ip6h, end, &hdrlen, &proto, &frag))
-                return (ENOSPC);
+        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) {