Merge "Fix bug with double unload on unsuccessful dlopen"

linker/linker.cpp

@@ -321,9 +321,7 @@ static void soinfo_free(soinfo* si) {
   TRACE("name %s: freeing soinfo @ %p", si->get_realpath(), si);
 
   if (!solist_remove_soinfo(si)) {
-    // TODO (dimitry): revisit this - for now preserving the logic
-    // but it does not look right, abort if soinfo is not in the list instead?
-    return;
+    async_safe_fatal("soinfo=%p is not in soinfo_list (double unload?)", si);
   }
 
   // clear links to/from si
@@ -1520,11 +1518,6 @@ bool find_libraries(android_namespace_t* ns,
     }
   });
 
-  auto failure_guard = android::base::make_scope_guard([&]() {
-    // Housekeeping
-    soinfo_unload(soinfos, soinfos_count);
-  });
-
   ZipArchiveCache zip_archive_cache;
 
   // Step 1: expand the list of load_tasks to include
@@ -1689,8 +1682,6 @@ bool find_libraries(android_namespace_t* ns,
         si->set_linked();
       }
     });
-
-    failure_guard.Disable();
   }
 
   return linked;
@@ -1700,7 +1691,7 @@ static soinfo* find_library(android_namespace_t* ns,
                             const char* name, int rtld_flags,
                             const android_dlextinfo* extinfo,
                             soinfo* needed_by) {
-  soinfo* si;
+  soinfo* si = nullptr;
 
   // readers_map is shared across recursive calls to find_libraries.
   // However, the map is not shared across different threads.
@@ -1719,6 +1710,9 @@ static soinfo* find_library(android_namespace_t* ns,
                              false /* add_as_children */,
                              true /* search_linked_namespaces */,
                              readers_map)) {
+    if (si != nullptr) {
+      soinfo_unload(si);
+    }
     return nullptr;
   }
 

tests/dlext_test.cpp

@@ -1051,6 +1051,46 @@ TEST(dlext, ns_unload_between_namespaces) {
             "\" wasn't loaded and RTLD_NOLOAD prevented it", dlerror());
 }
 
+TEST(dlext, ns_unload_between_namespaces_missing_symbol) {
+  ASSERT_TRUE(android_init_anonymous_namespace(g_core_shared_libs.c_str(), nullptr));
+
+  const std::string public_ns_search_path =  get_testlib_root() + "/public_namespace_libs";
+  const std::string private_ns_search_path = get_testlib_root() + "/private_namespace_libs";
+
+  android_namespace_t* ns_public =
+          android_create_namespace("public",
+                                   nullptr,
+                                   public_ns_search_path.c_str(),
+                                   ANDROID_NAMESPACE_TYPE_ISOLATED,
+                                   nullptr,
+                                   nullptr);
+
+  ASSERT_TRUE(android_link_namespaces(ns_public, nullptr, g_core_shared_libs.c_str())) << dlerror();
+
+  android_namespace_t* ns_private =
+          android_create_namespace("private",
+                                   nullptr,
+                                   private_ns_search_path.c_str(),
+                                   ANDROID_NAMESPACE_TYPE_ISOLATED,
+                                   nullptr,
+                                   nullptr);
+
+  ASSERT_TRUE(android_link_namespaces(ns_private, ns_public, "libtest_missing_symbol.so")) << dlerror();
+  ASSERT_TRUE(android_link_namespaces(ns_private, nullptr, g_core_shared_libs.c_str())) << dlerror();
+
+  android_dlextinfo extinfo;
+  extinfo.flags = ANDROID_DLEXT_USE_NAMESPACE;
+  extinfo.library_namespace = ns_private;
+
+  void* handle = android_dlopen_ext((public_ns_search_path + "/libtest_missing_symbol.so").c_str(),
+                                    RTLD_NOW,
+                                    &extinfo);
+  ASSERT_TRUE(handle == nullptr);
+  ASSERT_EQ(std::string("dlopen failed: cannot locate symbol \"dlopen_testlib_missing_symbol\" referenced by \"") +
+            public_ns_search_path + "/libtest_missing_symbol.so\"...",
+            dlerror());
+}
+
 TEST(dlext, ns_greylist_enabled) {
   ASSERT_TRUE(android_init_anonymous_namespace(g_core_shared_libs.c_str(), nullptr));
 

tests/libs/Android.bp

@@ -112,6 +112,18 @@ cc_test_library {
     srcs: ["dlopen_testlib_simple.cpp"],
 }
 
+// -----------------------------------------------------------------------------
+// Library used by dlfcn unload tests
+// -----------------------------------------------------------------------------
+cc_test_library {
+    name: "libtest_missing_symbol",
+    defaults: ["bionic_testlib_defaults"],
+    srcs: ["dlopen_testlib_missing_symbol.cpp"],
+    allow_undefined_symbols: true,
+    relative_install_path: "bionic-loader-test-libs/public_namespace_libs",
+}
+
+// -----------------------------------------------------------------------------
 // -----------------------------------------------------------------------------
 // Library used by dlfcn nodelete tests
 // -----------------------------------------------------------------------------

tests/libs/dlopen_testlib_missing_symbol.cpp

@@ -0,0 +1,37 @@
+/*
+ * Copyright (C) 2017 The Android Open Source Project
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *  * Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ *  * Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in
+ *    the documentation and/or other materials provided with the
+ *    distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
+ * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
+ * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
+ * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
+ * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
+ * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
+ * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
+ * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ */
+
+#include <stdint.h>
+#include <stdlib.h>
+
+extern "C" void dlopen_testlib_missing_symbol();
+
+extern "C" bool dlopen_testlib_simple_func() {
+  dlopen_testlib_missing_symbol();
+  return true;
+}