1 files changed, 102 insertions, 0 deletions
diff --git a/elf/tst-dlopen-tlsreinitmod3.c b/elf/tst-dlopen-tlsreinitmod3.c
new file mode 100644
index 0000000000..ef769c5131
--- /dev/null
+++ b/elf/tst-dlopen-tlsreinitmod3.c
@@ -0,0 +1,102 @@
+/* Test that dlopen preserves already accessed TLS (bug 31717), module 3.
+   Copyright (C) 2024 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
+   <https://www.gnu.org/licenses/>.  */
+
+#include <dlfcn.h>
+#include <stdbool.h>
+#include <stdio.h>
+#include <unistd.h>
+
+/* Used to verify from the main program that the test ran.  */
+bool tlsreinitmod3_tested;
+
+/* This TLS variable must not revert back to the initial state after
+   dlopen.  */
+static __thread int tlsreinitmod3_state = 1;
+
+/* Set from the ELF constructor during dlopen.  */
+static bool tlsreinitmod3_constructed;
+
+/* Second half of test, behind a compiler barrier.  The compiler
+   barrier is necessary to prevent carrying over TLS address
+   information from call_tlsreinitmod3 to call_tlsreinitmod3_tail.  */
+void call_tlsreinitmod3_tail (void *self) __attribute__ ((weak));
+
+/* Called from tst-dlopen-tlsreinitmod2.so.  */
+void
+call_tlsreinitmod3 (void)
+{
+  printf ("info: call_tlsreinitmod3 invoked (state=%d)\n",
+          tlsreinitmod3_state);
+
+  if (tlsreinitmod3_constructed)
+    {
+      puts ("error: call_tlsreinitmod3 called after ELF constructor");
+      fflush (stdout);
+      /* Cannot rely on test harness due to dynamic linking.  */
+      _exit (1);
+    }
+
+  tlsreinitmod3_state = 2;
+
+  /* Self-dlopen.  This will run the ELF constructor.   */
+  void *self = dlopen ("tst-dlopen-tlsreinitmod3.so", RTLD_NOW);
+  if (self == NULL)
+    {
+      printf ("error: dlopen: %s\n", dlerror ());
+      fflush (stdout);
+      /* Cannot rely on test harness due to dynamic linking.  */
+      _exit (1);
+    }
+
+  call_tlsreinitmod3_tail (self);
+}
+
+void
+call_tlsreinitmod3_tail (void *self)
+{
+  printf ("info: dlopen returned in tlsreinitmod3 (state=%d)\n",
+          tlsreinitmod3_state);
+
+  if (!tlsreinitmod3_constructed)
+    {
+      puts ("error: dlopen did not call tlsreinitmod3 ELF constructor");
+      fflush (stdout);
+      /* Cannot rely on test harness due to dynamic linking.  */
+      _exit (1);
+    }
+
+  if (tlsreinitmod3_state != 2)
+    {
+      puts ("error: TLS state reverted in tlsreinitmod3");
+      fflush (stdout);
+      /* Cannot rely on test harness due to dynamic linking.  */
+      _exit (1);
+    }
+
+  dlclose (self);
+
+  /* Signal test completion to the main program.  */
+  tlsreinitmod3_tested = true;
+}
+
+static void __attribute__ ((constructor))
+tlsreinitmod3_init (void)
+{
+  puts ("info: constructor of tst-dlopen-tlsreinitmod3.so invoked");
+  tlsreinitmod3_constructed = true;
+}