gethostbyname() returns incorrect information

/* Standard program for confirming Project Spamhaus DNS lookup */
/* If this fails, something's wrong somewhere in DNS */
#include <stdio.h>
#include <string.h>
#include <stdlib.h>
#include <sys/socket.h>
#include <arpa/inet.h>
#include <netinet/in.h>
#include <unistd.h>
#include <errno.h>
#include <string.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <netdb.h>


void main() {


  static int oct1, oct2, oct3, oct4;
  struct in_addr addr;
  struct hostent *hp = 0;


/* =====================================================
 * Stage 1.  Lookup 2.0.0.127.sbl.spamhaus.org
 *
 * Should return 127.0.0.2
 * =====================================================
 */


  printf("\n================== FIRST TEST ===================\n\n");
  printf("Lookup 2.0.0.127.sbl.spamhaus.org\n");
  printf("Expected result success, 127.0.0.2\n\n");
  hp = gethostbyname("2.0.0.127.sbl.spamhaus.org");
  if (hp == NULL) {
    printf("Validation failed, h_errno = %d <%s>\n",
            h_errno, hstrerror(h_errno));
    return;
  }


  /* Isn't this next line horrible? */
  addr.s_addr = *(u_long *) hp->h_addr_list[0];
  printf("Official name = <%s>\n", hp->h_name);
  printf("Address length in bytes = %d\n", hp->h_length);
  sscanf(inet_ntoa(addr), "%u.%u.%u.%u",
         &oct1, &oct2, &oct3, &oct4);
  printf("Resolved to %u.%u.%u.%u\n\n", oct1, oct2, oct3, oct4);


  if ((oct1 != 127) || (oct2 != 0) || (oct3 != 0) || (oct4 != 2)) {
    printf("Validation failed, result not 127.0.0.2\n\n");
    printf("================== FAILURE ===================\n\n");
    return;
  }

  printf ("Validation successful\n\n");

/* =====================================================
 * Stage 2.  Lookup 1.0.0.127.sbl.spamhaus.org
 *
 * Should return failure
 * =====================================================
 */

  printf("================== SECOND TEST ===================\n\n");
  printf("Lookup 1.0.0.127.sbl.spamhaus.org\n");
  printf("Expected result failure\n\n");
  hp = gethostbyname("1.0.0.127.sbl.spamhaus.org");
  if (hp == NULL) {
    printf("Lookup failed, h_errno = %d <%s>\n\n",
            h_errno, hstrerror(h_errno));
    printf ("Validation successful\n\n");
    printf("================= ALL TESTS PASS =================\n\n");
    return;
  }

  /* Isn't this next line horrible? */
  addr.s_addr = *(u_long *) hp->h_addr_list[0];
  printf("Official name = <%s>\n", hp->h_name);
  printf("Address length in bytes = %d\n", hp->h_length);
  sscanf(inet_ntoa(addr), "%u.%u.%u.%u",
         &oct1, &oct2, &oct3, &oct4);
  printf("Resolved to %u.%u.%u.%u\n\n", oct1, oct2, oct3, oct4);
  printf("Validation failed, result should not exist\n\n");
  printf("================== FAILURE ===================\n\n");
  return;
}

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root:/usr/src/mod_spamhaus/src> ./a.out

================== FIRST TEST ===================

Lookup 2.0.0.127.sbl.spamhaus.org
Expected result success, 127.0.0.2

Official name = <2.0.0.127.sbl.spamhaus.org>
Address length in bytes = 4
Resolved to 127.0.0.2

Validation successful

================== SECOND TEST ===================

Lookup 1.0.0.127.sbl.spamhaus.org
Expected result failure

Official name = <1.0.0.127.sbl.spamhaus.org.my-domain-name.com>
Address length in bytes = 4
Resolved to xxx.yyy.zzz.aaa (the host's IP address)

Validation failed, result should not exist

================== FAILURE ===================

root:/usr/src/mod_spamhaus/src>

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root:/usr/src/mod_spamhaus/src> nslookup 1.0.0.127.sbl.spamhaus.org
Server:         84.200.69.80
Address:        84.200.69.80#53

** server can't find 1.0.0.127.sbl.spamhaus.org: NXDOMAIN
root:/usr/src/mod_spamhaus/src> dig 1.0.0.127.sbl.spamhaus.org

; <<>> DiG 9.10.3-P4-Debian <<>> 1.0.0.127.sbl.spamhaus.org
;; global options: +cmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: NXDOMAIN, id: 58161
;; flags: qr rd ra; QUERY: 1, ANSWER: 0, AUTHORITY: 1, ADDITIONAL: 1

;; OPT PSEUDOSECTION:
; EDNS: version: 0, flags:; udp: 4096
;; QUESTION SECTION:
;1.0.0.127.sbl.spamhaus.org.    IN      A

;; AUTHORITY SECTION:
sbl.spamhaus.org.       8       IN      SOA     need.to.know.only. hostmaster.spamhaus.org. 2011051822 3600 600 432000 10

;; Query time: 127 msec
;; SERVER: 84.200.69.80#53(84.200.69.80)
;; WHEN: Thu Nov 05 18:23:28 GMT 2020
;; MSG SIZE  rcvd: 119

root:/usr/src/mod_spamhaus/src>

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# 1.1.1.1 open nameserver
# Four ones does not properly resolve spamhaus lookups
# nameserver 1.1.1.1


# OpenNIC nameservers
# May be blocked in iptables
# nameserver 172.98.193.42


# dns.watch IPv4 nameservers
nameserver 84.200.69.80    # resolver1.dns.watch
nameserver 84.200.70.40    # resolver2.dns.watch
nameserver 208.67.220.220
nameserver 208.67.222.222

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