commit 0044cd188e738c863da4e9cb44687623436890d7
author Ryan Prichard <rprichard@google.com> Tue Apr 03 20:03:12 2018 -0700
committer Ryan Prichard <rprichard@google.com> Wed Apr 04 16:10:37 2018 -0700
tree 7ff6ac6762fe1b86deb1a9c071ba579234f7b8a2
parent 8b70a0266d42297e9b38e6209588eb3621843e95

Fix race in ld.config.txt tests

The tests can run in parallel, and if they do, one test can truncate
ld.config.txt while another test is reading it (via the loader). Fix the
issue by using a TemporaryFile as the LD_CONFIG_FILE.

Test: adb shell /data/nativetest64/bionic-unit-tests/bionic-unit-tests  --gtest_filter=dl.exec_with_ld_config_file:dl.exec_with_ld_config_file_with_ld_preload:dl.disable_ld_config_file --gtest_repeat=1000
Bug: b/77555708
Change-Id: I9763caa076ece30d1a0eb9c8892a310ac51543b6
(cherry picked from commit 6c3f97d2360ba1a2b2be160003fa3b4dd7b33ae1)

tests/dl_test.cpp

diff --git a/tests/dl_test.cpp b/tests/dl_test.cpp
index 7444e3a..38d7783 100644
--- a/tests/dl_test.cpp
+++ b/tests/dl_test.cpp
@@ -31,6 +31,7 @@
 #include <fstream>
 
 #include "gtest_globals.h"
+#include "TemporaryFile.h"
 #include "utils.h"
 
 extern "C" int main_global_default_serial() {
@@ -167,8 +168,8 @@
 }
 
 #if defined(__BIONIC__)
-static void create_ld_config_file(std::string& config_file) {
-  std::ofstream fout(config_file.c_str(), std::ios::out);
+static void create_ld_config_file(const char* config_file) {
+  std::ofstream fout(config_file, std::ios::out);
   fout << "dir.test = " << get_testlib_root() << "/ld_config_test_helper/" << std::endl
        << "[test]" << std::endl
        << "additional.namespaces = ns2" << std::endl
@@ -196,9 +197,9 @@
   }
   std::string helper = get_testlib_root() +
       "/ld_config_test_helper/ld_config_test_helper";
-  std::string config_file = get_testlib_root() + "/ld.config.txt";
-  create_ld_config_file(config_file);
-  std::string env = std::string("LD_CONFIG_FILE=") + config_file;
+  TemporaryFile config_file;
+  create_ld_config_file(config_file.filename);
+  std::string env = std::string("LD_CONFIG_FILE=") + config_file.filename;
   chmod(helper.c_str(), 0755);
   ExecTestHelper eth;
   eth.SetArgs({ helper.c_str(), nullptr });
@@ -218,9 +219,9 @@
   }
   std::string helper = get_testlib_root() +
       "/ld_config_test_helper/ld_config_test_helper";
-  std::string config_file = get_testlib_root() + "/ld.config.txt";
-  create_ld_config_file(config_file);
-  std::string env = std::string("LD_CONFIG_FILE=") + config_file;
+  TemporaryFile config_file;
+  create_ld_config_file(config_file.filename);
+  std::string env = std::string("LD_CONFIG_FILE=") + config_file.filename;
   std::string env2 = std::string("LD_PRELOAD=") + get_testlib_root() + "/ld_config_test_helper_lib3.so";
   chmod(helper.c_str(), 0755);
   ExecTestHelper eth;
@@ -248,9 +249,9 @@
   std::string error_message = "CANNOT LINK EXECUTABLE \"" + get_testlib_root() + "/ld_config_test_helper/ld_config_test_helper\": library \"ld_config_test_helper_lib1.so\" not found\n";
   std::string helper = get_testlib_root() +
       "/ld_config_test_helper/ld_config_test_helper";
-  std::string config_file = get_testlib_root() + "/ld.config.txt";
-  create_ld_config_file(config_file);
-  std::string env = std::string("LD_CONFIG_FILE=") + config_file;
+  TemporaryFile config_file;
+  create_ld_config_file(config_file.filename);
+  std::string env = std::string("LD_CONFIG_FILE=") + config_file.filename;
   chmod(helper.c_str(), 0755);
   ExecTestHelper eth;
   eth.SetArgs({ helper.c_str(), nullptr });