diff --git a/elf/Makefile b/elf/Makefile
index 5c47daee12..38d08e03b8 100644
--- a/elf/Makefile
+++ b/elf/Makefile
@@ -223,7 +223,7 @@ tests += restest1 preloadtest loadfail multiload origtest resolvfail \
tst-single_threaded tst-single_threaded-pthread \
tst-tls-ie tst-tls-ie-dlmopen argv0test \
tst-glibc-hwcaps tst-glibc-hwcaps-prepend tst-glibc-hwcaps-mask \
- tst-tls20 tst-tls21 tst-dlmopen-dlerror
+ tst-tls20 tst-tls21 tst-dlmopen-dlerror tst-dlmopen-gethostbyname
# reldep9
tests-internal += loadtest unload unload2 circleload1 \
neededtest neededtest2 neededtest3 neededtest4 \
@@ -347,6 +347,7 @@ modules-names = testobj1 testobj2 testobj3 testobj4 testobj5 testobj6 \
libmarkermod4-1 libmarkermod4-2 libmarkermod4-3 libmarkermod4-4 \
tst-tls20mod-bad tst-tls21mod tst-dlmopen-dlerror-mod \
tst-auxvalmod \
+ tst-dlmopen-gethostbyname-mod \
# Most modules build with _ISOMAC defined, but those filtered out
# depend on internal headers.
@@ -1832,3 +1833,5 @@ $(objpfx)tst-tls21mod.so: $(tst-tls-many-dynamic-modules:%=$(objpfx)%.so)
$(objpfx)tst-getauxval-static.out: $(objpfx)tst-auxvalmod.so
tst-getauxval-static-ENV = LD_LIBRARY_PATH=$(objpfx):$(common-objpfx)
+
+$(objpfx)tst-dlmopen-gethostbyname.out: $(objpfx)tst-dlmopen-gethostbyname-mod.so
diff --git a/elf/dl-libc.c b/elf/dl-libc.c
index 8e0734f44c..a49df22029 100644
--- a/elf/dl-libc.c
+++ b/elf/dl-libc.c
@@ -43,8 +43,8 @@ dlerror_run (void (*operate) (void *), void *args)
const char *last_errstring = NULL;
bool malloced;
- int result = (_dl_catch_error (&objname, &last_errstring, &malloced,
- operate, args)
+ int result = (GLRO (dl_catch_error) (&objname, &last_errstring, &malloced,
+ operate, args)
?: last_errstring != NULL);
if (result && malloced)
diff --git a/elf/tst-dlmopen-gethostbyname-mod.c b/elf/tst-dlmopen-gethostbyname-mod.c
new file mode 100644
index 0000000000..9a68ea5050
--- /dev/null
+++ b/elf/tst-dlmopen-gethostbyname-mod.c
@@ -0,0 +1,29 @@
+/* Exercise dlerror_run in elf/dl-libc.c after dlmopen, via NSS. Helper module.
+ Copyright (C) 2021 Free Software Foundation, Inc.
+ This file is part of the GNU C Library.
+
+ The GNU C Library is free software; you can redistribute it and/or
+ modify it under the terms of the GNU Lesser General Public
+ License as published by the Free Software Foundation; either
+ version 2.1 of the License, or (at your option) any later version.
+
+ The GNU C Library is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ Lesser General Public License for more details.
+
+ You should have received a copy of the GNU Lesser General Public
+ License along with the GNU C Library; if not, see
+ . */
+
+#include
+#include
+
+void
+call_gethostbyname (void)
+{
+ __nss_configure_lookup ("hosts", "files");
+ /* This should not terminate the process due to a missing
+ _nss_files_getcanonname_r symbol. */
+ gethostbyname ("localhost");
+}
diff --git a/elf/tst-dlmopen-gethostbyname.c b/elf/tst-dlmopen-gethostbyname.c
new file mode 100644
index 0000000000..12deb29900
--- /dev/null
+++ b/elf/tst-dlmopen-gethostbyname.c
@@ -0,0 +1,31 @@
+/* Exercise dlerror_run in elf/dl-libc.c after dlmopen, via NSS (bug 27646).
+ Copyright (C) 2021 Free Software Foundation, Inc.
+ This file is part of the GNU C Library.
+
+ The GNU C Library is free software; you can redistribute it and/or
+ modify it under the terms of the GNU Lesser General Public
+ License as published by the Free Software Foundation; either
+ version 2.1 of the License, or (at your option) any later version.
+
+ The GNU C Library is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ Lesser General Public License for more details.
+
+ You should have received a copy of the GNU Lesser General Public
+ License along with the GNU C Library; if not, see
+ . */
+
+#include
+
+static int
+do_test (void)
+{
+ void *handle = xdlmopen (LM_ID_NEWLM, "tst-dlmopen-gethostbyname-mod.so",
+ RTLD_NOW);
+ void (*call_gethostbyname) (void) = xdlsym (handle, "call_gethostbyname");
+ call_gethostbyname ();
+ return 0;
+}
+
+#include