diff --git a/Implement-full-roundtrip-for-lookup-functionality.patch b/Implement-full-roundtrip-for-lookup-functionality.patch
new file mode 100644
index 0000000000000000000000000000000000000000..ffcdfbe0f1d59a71af441a328a80bb968cecd6c3
--- /dev/null
+++ b/Implement-full-roundtrip-for-lookup-functionality.patch
@@ -0,0 +1,122 @@
+From c7b33a418d9426ee311db45473cb20bad94df26a Mon Sep 17 00:00:00 2001
+From: =?UTF-8?q?Tim=20R=C3=BChsen?= <tim.ruehsen@gmx.de>
+Date: Mon, 10 Feb 2020 15:10:54 +0100
+Subject: [PATCH] Implement full roundtrip for lookup functionality
+MIME-Version: 1.0
+Content-Type: text/plain; charset=UTF-8
+Content-Transfer-Encoding: 8bit
+
+With TR64 enabled (default), '☺i' was converted to 'xn-- o-oia59s'.
+The output contains an illegal space and thus could not be decoded any more.
+
+References:
+https://gitlab.com/libidn/libidn2/issues/78
+https://gitlab.isc.org/isc-projects/bind9/issues/1610
+
+Reported-by: Chris Malton
+---
+ lib/lookup.c        | 33 +++++++++++++++++++++++----------
+ tests/test-lookup.c |  5 +++++
+ 3 files changed, 29 insertions(+), 10 deletions(-)
+ 
+diff --git a/lib/lookup.c b/lib/lookup.c
+index a55f82b..5e5ff12 100644
+--- a/lib/lookup.c
++++ b/lib/lookup.c
+@@ -1,5 +1,6 @@
+ /* lookup.c - implementation of IDNA2008 lookup functions
+    Copyright (C) 2011-2017 Simon Josefsson
++   Copyright (C) 2017-2020 Tim Ruehsen
+ 
+    Libidn2 is free software: you can redistribute it and/or modify it
+    under the terms of either:
+@@ -123,7 +124,7 @@ label (const uint8_t * src, size_t srclen, uint8_t * dst, size_t * dstlen,
+        int flags)
+ {
+   size_t plen;
+-  uint32_t *p;
++  uint32_t *p = NULL;
+   const uint8_t *src_org = NULL;
+   uint8_t *src_allocated = NULL;
+   int rc, check_roundtrip = 0;
+@@ -187,10 +188,7 @@ label (const uint8_t * src, size_t srclen, uint8_t * dst, size_t * dstlen,
+ 	p, plen);
+ 
+       if (rc != IDN2_OK)
+-	{
+-	  free (p);
+-	  goto out;
+-	}
++	goto out;
+     }
+ 
+   dst[0] = 'x';
+@@ -200,7 +198,6 @@ label (const uint8_t * src, size_t srclen, uint8_t * dst, size_t * dstlen,
+ 
+   tmpl = *dstlen - 4;
+   rc = _idn2_punycode_encode_internal (plen, p, &tmpl, (char *) dst + 4);
+-  free (p);
+   if (rc != IDN2_OK)
+     goto out;
+ 
+@@ -210,15 +207,31 @@ label (const uint8_t * src, size_t srclen, uint8_t * dst, size_t * dstlen,
+   if (check_roundtrip)
+     {
+       if (srclen_org != *dstlen || c_strncasecmp ((char *) src_org, (char *) dst, srclen_org))
+-      {
+-        rc = IDN2_ALABEL_ROUNDTRIP_FAILED;
+-	goto out;
+-      }
++        {
++	  rc = IDN2_ALABEL_ROUNDTRIP_FAILED;
++	  goto out;
++        }
++    }
++  else if (!(flags & IDN2_NO_ALABEL_ROUNDTRIP))
++    {
++      rc = _idn2_punycode_decode_internal (*dstlen - 4, (char *) dst + 4, &label32_len, label_u32);
++      if (rc)
++        {
++	  rc = IDN2_ALABEL_ROUNDTRIP_FAILED;
++	  goto out;
++        }
++
++      if (plen != label32_len || u32_cmp (p, label_u32, label32_len))
++        {
++	  rc = IDN2_ALABEL_ROUNDTRIP_FAILED;
++	  goto out;
++        }
+     }
+ 
+   rc = IDN2_OK;
+ 
+ out:
++  free (p);
+   free (src_allocated);
+   return rc;
+ }
+diff --git a/tests/test-lookup.c b/tests/test-lookup.c
+index aa75e18..2b49cb1 100644
+--- a/tests/test-lookup.c
++++ b/tests/test-lookup.c
+@@ -1,5 +1,6 @@
+ /* test-lookup.c --- Self tests for IDNA processing
+    Copyright (C) 2011-2017 Simon Josefsson
++   Copyright (C) 2017-2020 Tim Ruehsen
+ 
+    This program is free software: you can redistribute it and/or modify
+    it under the terms of the GNU General Public License as published by
+@@ -838,6 +839,10 @@ static const struct idna idna[] = {
+   {"\xc3\xa4_x", "xn--_x-uia", IDN2_OK, IDN2_TRANSITIONAL},
+   /* failing lookup round-trip */
+   {"xn--te_", "", IDN2_ALABEL_ROUNDTRIP_FAILED},
++  /* failing lookup round-trip: ☺ -> xn-- o-oia59s (illegal space in output, see https://gitlab.com/libidn/libidn2/issues/78) */
++  {"\xc3\xa2\xcb\x9c\xc2\xba", "", IDN2_DISALLOWED, IDN2_NO_TR46},
++  {"\xc3\xa2\xcb\x9c\xc2\xba", "", IDN2_ALABEL_ROUNDTRIP_FAILED, IDN2_TRANSITIONAL},
++  {"\xc3\xa2\xcb\x9c\xc2\xba", "", IDN2_ALABEL_ROUNDTRIP_FAILED, IDN2_NONTRANSITIONAL},
+ };
+ 
+ static int ok = 0, failed = 0;
+-- 
+1.8.3.1
+
diff --git a/libidn2.spec b/libidn2.spec
index 024ad50e94506551d466c4a140cd50b8840650f6..913d7cc8cb65de617567281f6cf1c99cff4abd03 100644
--- a/libidn2.spec
+++ b/libidn2.spec
@@ -1,12 +1,13 @@
 Name:           libidn2
 Version:        2.3.0
-Release:        2
+Release:        3
 Summary:        GNU IDN Library
 License:        (GPLv2+ or LGPLv3+) and GPLv3+
 URL:            https://www.gnu.org/software/libidn/#libidn2
 Source0:        https://ftp.gnu.org/gnu/libidn/%{name}-%{version}.tar.gz
 
 Patch0:         bugfix-libidn2-change-rpath.patch
+Patch1:         Implement-full-roundtrip-for-lookup-functionality.patch
 
 #Dependency
 BuildRequires:  gcc gettext libunistring-devel autoconf texinfo automake
@@ -74,6 +75,12 @@ make %{?_smp_mflags} -C tests check
 %{_datadir}/gtk-doc/
 
 %changelog
+* Wed Jun 24 2020 wangchen <wangchen137@huawei.com> - 2.3.0-3
+- Type:bugfix
+- ID:NA
+- SUG:NA
+- DESC:Implement full roundtrip for lookup functionality
+
 * Wed Jun 17 2020 Liquor <lirui130@huawei.com> - 2.3.0-2
 - Type:bugfix
 - ID:NA