diff --git a/SOURCES/glibc-rh1777797.patch b/SOURCES/glibc-rh1777797.patch
new file mode 100644
index 0000000..e68afdd
--- /dev/null
+++ b/SOURCES/glibc-rh1777797.patch
@@ -0,0 +1,88 @@
+commit bfdb731438206b0f70fe7afa890681155c30b419
+Author: Stefan Liebler <stli@linux.ibm.com>
+Date:   Wed Nov 27 12:35:40 2019 +0100
+
+    S390: Fix handling of needles crossing a page in strstr z15 ifunc-variant. [BZ #25226]
+    
+    If the specified needle crosses a page-boundary, the s390-z15 ifunc variant of
+    strstr truncates the needle which results in invalid results.
+    
+    This is fixed by loading the needle beyond the page boundary to v18 instead of v16.
+    The bug is sometimes observable in test-strstr.c in check1 and check2 as the
+    haystack and needle is stored on stack. Thus the needle can be on a page boundary.
+    
+    check2 is now extended to test haystack / needles located on stack, at end of page
+    and on two pages.
+    
+    This bug was introduced with commit 6f47401bd5fc71209219779a0426170a9a7395b0
+    ("S390: Add arch13 strstr ifunc variant.") and is already released in glibc 2.30.
+
+diff --git a/string/test-strstr.c b/string/test-strstr.c
+index 5861b01b73e4c315..e9e14c1ee605516e 100644
+--- a/string/test-strstr.c
++++ b/string/test-strstr.c
+@@ -138,16 +138,45 @@ check1 (void)
+ static void
+ check2 (void)
+ {
+-  const char s1[] = ", enable_static, \0, enable_shared, ";
++  const char s1_stack[] = ", enable_static, \0, enable_shared, ";
++  const size_t s1_byte_count = 18;
++  const char *s2_stack = &(s1_stack[s1_byte_count]);
++  const size_t s2_byte_count = 18;
+   char *exp_result;
+-  char *s2 = (void *) buf1 + page_size - 18;
++  const size_t page_size_real = getpagesize ();
+ 
+-  strcpy (s2, s1);
+-  exp_result = stupid_strstr (s1, s1 + 18);
++  /* Haystack at end of page.  The following page is protected.  */
++  char *s1_page_end = (void *) buf1 + page_size - s1_byte_count;
++  strcpy (s1_page_end, s1_stack);
++
++  /* Haystack which crosses a page boundary.
++     Note: page_size is at least 2 * getpagesize.  See test_init.  */
++  char *s1_page_cross = (void *) buf1 + page_size_real - 8;
++  strcpy (s1_page_cross, s1_stack);
++
++  /* Needle at end of page.  The following page is protected.  */
++  char *s2_page_end = (void *) buf2 + page_size - s2_byte_count;
++  strcpy (s2_page_end, s2_stack);
++
++  /* Needle which crosses a page boundary.
++     Note: page_size is at least 2 * getpagesize.  See test_init.  */
++  char *s2_page_cross = (void *) buf2 + page_size_real - 8;
++  strcpy (s2_page_cross, s2_stack);
++
++  exp_result = stupid_strstr (s1_stack, s2_stack);
+   FOR_EACH_IMPL (impl, 0)
+     {
+-      check_result (impl, s1, s1 + 18, exp_result);
+-      check_result (impl, s2, s1 + 18, exp_result);
++      check_result (impl, s1_stack, s2_stack, exp_result);
++      check_result (impl, s1_stack, s2_page_end, exp_result);
++      check_result (impl, s1_stack, s2_page_cross, exp_result);
++
++      check_result (impl, s1_page_end, s2_stack, exp_result);
++      check_result (impl, s1_page_end, s2_page_end, exp_result);
++      check_result (impl, s1_page_end, s2_page_cross, exp_result);
++
++      check_result (impl, s1_page_cross, s2_stack, exp_result);
++      check_result (impl, s1_page_cross, s2_page_end, exp_result);
++      check_result (impl, s1_page_cross, s2_page_cross, exp_result);
+     }
+ }
+ 
+diff --git a/sysdeps/s390/strstr-arch13.S b/sysdeps/s390/strstr-arch13.S
+index 929b026adfeba740..faa969849e09c2e1 100644
+--- a/sysdeps/s390/strstr-arch13.S
++++ b/sysdeps/s390/strstr-arch13.S
+@@ -164,7 +164,7 @@ ENTRY(STRSTR_ARCH13)
+ 	vfenezb	%v19,%v18,%v18	/* Search zero in loaded needle bytes.  */
+ 	veclb	%v19,%v21	/* Zero index <= max loaded byte index?  */
+ 	jle	.Lneedle_loaded	/* -> v18 contains full needle.  */
+-	vl	%v16,0(%r3)	/* Load needle beyond page boundary.  */
++	vl	%v18,0(%r3)	/* Load needle beyond page boundary.  */
+ 	vfenezb	%v19,%v18,%v18
+ 	j	.Lneedle_loaded
+ END(STRSTR_ARCH13)
diff --git a/SPECS/glibc.spec b/SPECS/glibc.spec
index a416a96..7435e08 100644
--- a/SPECS/glibc.spec
+++ b/SPECS/glibc.spec
@@ -1,6 +1,6 @@
 %define glibcsrcdir glibc-2.28
 %define glibcversion 2.28
-%define glibcrelease 72%{?dist}
+%define glibcrelease 72%{?dist}.1
 # Pre-release tarballs are pulled in from git using a command that is
 # effectively:
 #
@@ -315,6 +315,7 @@ Patch180: glibc-rh1717438.patch
 Patch181: glibc-rh1727152.patch
 Patch182: glibc-rh1724975.patch
 Patch183: glibc-rh1722215.patch
+Patch184: glibc-rh1777797.patch
 
 ##############################################################################
 # Continued list of core "glibc" package information:
@@ -2201,6 +2202,9 @@ fi
 %files -f compat-libpthread-nonshared.filelist -n compat-libpthread-nonshared
 
 %changelog
+* Thu Nov 28 2019 Florian Weimer <fweimer@redhat.com> - 2.28-72.1
+- s390x: Fix z15 strstr for patterns crossing pages (#1777797)
+
 * Mon Jul 22 2019 Carlos O'Donell <carlos@redhat.com> - 2.28-72
 - Skip wide buffer handling for legacy stdio handles (#1722215)