nss_dns: Fix assertion failure in _nss_dns_getcanonname_r [BZ #19865]

(cherry picked from commit d29fb41f4431ca35ea360498ef9d37558ce90d76)
(cherry picked from commit 49203a513f86e5238d43da23505a600bef1a5d7a)

diff --git a/resolv/nss_dns/dns-canon.c b/resolv/nss_dns/dns-canon.c
index 27255fda58c78fe2fed86eb3a1c4ca862c0f736c..fd73f19984c45cf14f67fb17891541b12599980e 100644 (file)
--- a/resolv/nss_dns/dns-canon.c
+++ b/resolv/nss_dns/dns-canon.c
@@ -144,6 +144,13 @@ _nss_dns_getcanonname_r (const char *name, char *buffer, size_t buflen,
              ptr += sizeof (uint16_t) + __ns_get16 (ptr);
            }
        }
+
+      /* Restore original buffer before retry.  */
+      if (ansp.ptr != buf)
+       {
+         free (ansp.ptr);
+         ansp.ptr = buf;
+       }
     }
 
  out: