commit c36e7cca3571b0c92b09409c1df86a142596c210
Author: Florian Weimer <fweimer@redhat.com>
Date:   Tue Aug 30 10:02:49 2022 +0200

    nss_dns: In gaih_getanswer_slice, skip strange aliases (bug 12154)
    
    If the name is not a host name, skip adding it to the result, instead
    of reporting query failure.  This fixes bug 12154 for getaddrinfo.
    
    This commit still keeps the old parsing code, and only adjusts when
    a host name is copied.
    
    Reviewed-by: Siddhesh Poyarekar <siddhesh@sourceware.org>
    (cherry picked from commit 32b599ac8c21c4c332cc3900a792a1395bca79c7)

diff --git a/resolv/nss_dns/dns-host.c b/resolv/nss_dns/dns-host.c
index 10c21e1e827cde12..1cb3be71f04d98eb 100644
--- a/resolv/nss_dns/dns-host.c
+++ b/resolv/nss_dns/dns-host.c
@@ -971,12 +971,12 @@ gaih_getanswer_slice (const querybuf *answer, int anslen, const char *qname,
 
 	  n = -1;
 	}
-      if (__glibc_unlikely (n < 0 || __libc_res_hnok (buffer) == 0))
+      if (__glibc_unlikely (n < 0))
 	{
 	  ++had_error;
 	  continue;
 	}
-      if (*firstp && canon == NULL)
+      if (*firstp && canon == NULL && __libc_res_hnok (buffer))
 	{
 	  h_name = buffer;
 	  buffer += h_namelen;
@@ -1022,14 +1022,14 @@ gaih_getanswer_slice (const querybuf *answer, int anslen, const char *qname,
 
 	  n = __libc_dn_expand (answer->buf, end_of_message, cp,
 				tbuf, sizeof tbuf);
-	  if (__glibc_unlikely (n < 0 || __libc_res_hnok (tbuf) == 0))
+	  if (__glibc_unlikely (n < 0))
 	    {
 	      ++had_error;
 	      continue;
 	    }
 	  cp += n;
 
-	  if (*firstp)
+	  if (*firstp && __libc_res_hnok (tbuf))
 	    {
 	      /* Reclaim buffer space.  */
 	      if (h_name + h_namelen == buffer)