Remove all loaded objects if dlopen fails, ignoring NODELETE [BZ #20839]

This introduces a “pending NODELETE” state in the link map, which is
flipped to the persistent NODELETE state late in dlopen, via
activate_nodelete.    During initial relocation, symbol binding
records pending NODELETE state only.  dlclose ignores pending NODELETE
state.  Taken together, this results that a partially completed dlopen
is rolled back completely because new NODELETE mappings are unloaded.

Tested on x86_64-linux-gnu and i386-linux-gnu.

Change-Id: Ib2a3d86af6f92d75baca65431d74783ee0dbc292

1 files changed, 29 insertions, 0 deletions

diff --git a/elf/tst-dlopenfailmod2.c b/elf/tst-dlopenfailmod2.c
new file mode 100644
index 0000000000..7d600386c1
--- /dev/null
+++ b/elf/tst-dlopenfailmod2.c
@@ -0,0 +1,29 @@
+/* Module which depends on on a NODELETE module, and can be loaded.
+   Copyright (C) 2019 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 <pthread.h>
+#include <stdio.h>
+
+/* Force linking against libpthread.  */
+void *pthread_create_reference = pthread_create;
+
+static void __attribute__ ((constructor))
+init (void)
+{
+  puts ("info: tst-dlopenfailmod2.so constructor invoked");
+}