import FIREFOX_52_6_0esr_RELEASE from mozilla-esr52 hg repo

2026-09-09 01:08:39 +09:00 · 2018-01-19 03:59:58 +08:00 · 2018-01-19 03:59:58 +08:00 · dcd9973243
commit dcd9973243
150858 changed files with 23884658 additions and 0 deletions
--- a/security/sandbox/linux/gtest/TestBroker.cpp
+++ b/security/sandbox/linux/gtest/TestBroker.cpp
@ -0,0 +1,626 @@
+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* vim: set ts=8 sts=2 et sw=2 tw=80: */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this file,
+ * You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#include "gtest/gtest.h"
+
+#include "broker/SandboxBroker.h"
+#include "broker/SandboxBrokerUtils.h"
+#include "SandboxBrokerClient.h"
+
+#include <errno.h>
+#include <fcntl.h>
+#include <pthread.h>
+#include <stdlib.h>
+#include <sched.h>
+#include <semaphore.h>
+#include <sys/stat.h>
+#include <sys/types.h>
+#include <time.h>
+#include <unistd.h>
+
+#include "mozilla/Atomics.h"
+#include "mozilla/NullPtr.h"
+#include "mozilla/PodOperations.h"
+#include "mozilla/UniquePtr.h"
+#include "mozilla/ipc/FileDescriptor.h"
+
+namespace mozilla {
+
+static const int MAY_ACCESS = SandboxBroker::MAY_ACCESS;
+static const int MAY_READ = SandboxBroker::MAY_READ;
+static const int MAY_WRITE = SandboxBroker::MAY_WRITE;
+static const int MAY_CREATE = SandboxBroker::MAY_CREATE;
+static const auto AddAlways = SandboxBroker::Policy::AddAlways;
+
+class SandboxBrokerTest : public ::testing::Test
+{
+  UniquePtr<SandboxBroker> mServer;
+  UniquePtr<SandboxBrokerClient> mClient;
+
+  UniquePtr<const SandboxBroker::Policy> GetPolicy() const;
+
+  template<class C, void (C::* Main)()>
+  static void* ThreadMain(void* arg) {
+    (static_cast<C*>(arg)->*Main)();
+    return nullptr;
+  }
+
+protected:
+  int Open(const char* aPath, int aFlags) {
+    return mClient->Open(aPath, aFlags);
+  }
+  int Access(const char* aPath, int aMode) {
+    return mClient->Access(aPath, aMode);
+  }
+  int Stat(const char* aPath, statstruct* aStat) {
+    return mClient->Stat(aPath, aStat);
+  }
+  int LStat(const char* aPath, statstruct* aStat) {
+    return mClient->LStat(aPath, aStat);
+  }
+  int Chmod(const char* aPath, int aMode) {
+    return mClient->Chmod(aPath, aMode);
+  }
+  int Link(const char* aPath, const char* bPath) {
+    return mClient->Link(aPath, bPath);
+  }
+  int Mkdir(const char* aPath, int aMode) {
+    return mClient->Mkdir(aPath, aMode);
+  }
+  int Symlink(const char* aPath, const char* bPath) {
+    return mClient->Symlink(aPath, bPath);
+  }
+  int Rename(const char* aPath, const char* bPath) {
+    return mClient->Rename(aPath, bPath);
+  }
+  int Rmdir(const char* aPath) {
+    return mClient->Rmdir(aPath);
+  }
+  int Unlink(const char* aPath) {
+    return mClient->Unlink(aPath);
+  }
+  ssize_t Readlink(const char* aPath, char* aBuff, size_t aSize) {
+    return mClient->Readlink(aPath, aBuff, aSize);
+  }
+
+  virtual void SetUp() {
+    ipc::FileDescriptor fd;
+
+    mServer = SandboxBroker::Create(GetPolicy(), getpid(), fd);
+    ASSERT_NE(mServer, nullptr);
+    ASSERT_TRUE(fd.IsValid());
+    auto rawFD = fd.ClonePlatformHandle();
+    mClient.reset(new SandboxBrokerClient(rawFD.release()));
+  }
+
+  template<class C, void (C::* Main)()>
+  void StartThread(pthread_t *aThread) {
+    ASSERT_EQ(0, pthread_create(aThread, nullptr, ThreadMain<C, Main>,
+                                static_cast<C*>(this)));
+  }
+
+  template<class C, void (C::* Main)()>
+  void RunOnManyThreads() {
+    static const int kNumThreads = 5;
+    pthread_t threads[kNumThreads];
+    for (int i = 0; i < kNumThreads; ++i) {
+      StartThread<C, Main>(&threads[i]);
+    }
+    for (int i = 0; i < kNumThreads; ++i) {
+      void* retval;
+      ASSERT_EQ(pthread_join(threads[i], &retval), 0);
+      ASSERT_EQ(retval, static_cast<void*>(nullptr));
+    }
+  }
+
+public:
+  void MultiThreadOpenWorker();
+  void MultiThreadStatWorker();
+};
+
+UniquePtr<const SandboxBroker::Policy>
+SandboxBrokerTest::GetPolicy() const
+{
+  UniquePtr<SandboxBroker::Policy> policy(new SandboxBroker::Policy());
+
+  policy->AddPath(MAY_READ | MAY_WRITE, "/dev/null", AddAlways);
+  policy->AddPath(MAY_READ, "/dev/zero", AddAlways);
+  policy->AddPath(MAY_READ, "/var/empty/qwertyuiop", AddAlways);
+  policy->AddPath(MAY_ACCESS, "/proc/self", AddAlways); // Warning: Linux-specific.
+  policy->AddPath(MAY_READ | MAY_WRITE, "/tmp", AddAlways);
+  policy->AddPath(MAY_READ | MAY_WRITE | MAY_CREATE, "/tmp/blublu", AddAlways);
+  policy->AddPath(MAY_READ | MAY_WRITE | MAY_CREATE, "/tmp/blublublu", AddAlways);
+
+  return Move(policy);
+}
+
+TEST_F(SandboxBrokerTest, OpenForRead)
+{
+  int fd;
+
+  fd = Open("/dev/null", O_RDONLY);
+  ASSERT_GE(fd, 0) << "Opening /dev/null failed.";
+  close(fd);
+  fd = Open("/dev/zero", O_RDONLY);
+  ASSERT_GE(fd, 0) << "Opening /dev/zero failed.";
+  close(fd);
+  fd = Open("/var/empty/qwertyuiop", O_RDONLY);
+  EXPECT_EQ(-ENOENT, fd) << "Opening allowed but nonexistent file succeeded.";
+  fd = Open("/proc/self", O_RDONLY);
+  EXPECT_EQ(-EACCES, fd) << "Opening stat-only file for read succeeded.";
+  fd = Open("/proc/self/stat", O_RDONLY);
+  EXPECT_EQ(-EACCES, fd) << "Opening disallowed file succeeded.";
+}
+
+TEST_F(SandboxBrokerTest, OpenForWrite)
+{
+  int fd;
+
+  fd = Open("/dev/null", O_WRONLY);
+  ASSERT_GE(fd, 0) << "Opening /dev/null write-only failed.";
+  close(fd);
+  fd = Open("/dev/null", O_RDWR);
+  ASSERT_GE(fd, 0) << "Opening /dev/null read/write failed.";
+  close(fd);
+  fd = Open("/dev/zero", O_WRONLY);
+  ASSERT_EQ(-EACCES, fd) << "Opening read-only-by-policy file write-only succeeded.";
+  fd = Open("/dev/zero", O_RDWR);
+  ASSERT_EQ(-EACCES, fd) << "Opening read-only-by-policy file read/write succeeded.";
+}
+
+TEST_F(SandboxBrokerTest, SimpleRead)
+{
+  int fd;
+  char c;
+
+  fd = Open("/dev/null", O_RDONLY);
+  ASSERT_GE(fd, 0);
+  EXPECT_EQ(0, read(fd, &c, 1));
+  close(fd);
+  fd = Open("/dev/zero", O_RDONLY);
+  ASSERT_GE(fd, 0);
+  ASSERT_EQ(1, read(fd, &c, 1));
+  EXPECT_EQ(c, '\0');
+}
+
+TEST_F(SandboxBrokerTest, Access)
+{
+  EXPECT_EQ(0, Access("/dev/null", F_OK));
+  EXPECT_EQ(0, Access("/dev/null", R_OK));
+  EXPECT_EQ(0, Access("/dev/null", W_OK));
+  EXPECT_EQ(0, Access("/dev/null", R_OK|W_OK));
+  EXPECT_EQ(-EACCES, Access("/dev/null", X_OK));
+  EXPECT_EQ(-EACCES, Access("/dev/null", R_OK|X_OK));
+
+  EXPECT_EQ(0, Access("/dev/zero", R_OK));
+  EXPECT_EQ(-EACCES, Access("/dev/zero", W_OK));
+  EXPECT_EQ(-EACCES, Access("/dev/zero", R_OK|W_OK));
+
+  EXPECT_EQ(-ENOENT, Access("/var/empty/qwertyuiop", R_OK));
+  EXPECT_EQ(-EACCES, Access("/var/empty/qwertyuiop", W_OK));
+
+  EXPECT_EQ(0, Access("/proc/self", F_OK));
+  EXPECT_EQ(-EACCES, Access("/proc/self", R_OK));
+
+  EXPECT_EQ(-EACCES, Access("/proc/self/stat", F_OK));
+}
+
+TEST_F(SandboxBrokerTest, Stat)
+{
+  statstruct realStat, brokeredStat;
+  ASSERT_EQ(0, statsyscall("/dev/null", &realStat)) << "Shouldn't ever fail!";
+  EXPECT_EQ(0, Stat("/dev/null", &brokeredStat));
+  EXPECT_EQ(realStat.st_ino, brokeredStat.st_ino);
+  EXPECT_EQ(realStat.st_rdev, brokeredStat.st_rdev);
+
+  EXPECT_EQ(-ENOENT, Stat("/var/empty/qwertyuiop", &brokeredStat));
+  EXPECT_EQ(-EACCES, Stat("/dev", &brokeredStat));
+
+  EXPECT_EQ(0, Stat("/proc/self", &brokeredStat));
+  EXPECT_TRUE(S_ISDIR(brokeredStat.st_mode));
+}
+
+TEST_F(SandboxBrokerTest, LStat)
+{
+  statstruct realStat, brokeredStat;
+  ASSERT_EQ(0, lstatsyscall("/dev/null", &realStat));
+  EXPECT_EQ(0, LStat("/dev/null", &brokeredStat));
+  EXPECT_EQ(realStat.st_ino, brokeredStat.st_ino);
+  EXPECT_EQ(realStat.st_rdev, brokeredStat.st_rdev);
+
+  EXPECT_EQ(-ENOENT, LStat("/var/empty/qwertyuiop", &brokeredStat));
+  EXPECT_EQ(-EACCES, LStat("/dev", &brokeredStat));
+
+  EXPECT_EQ(0, LStat("/proc/self", &brokeredStat));
+  EXPECT_TRUE(S_ISLNK(brokeredStat.st_mode));
+}
+
+static void PrePostTestCleanup(void)
+{
+  unlink("/tmp/blublu");
+  rmdir("/tmp/blublu");
+  unlink("/tmp/nope");
+  rmdir("/tmp/nope");
+  unlink("/tmp/blublublu");
+  rmdir("/tmp/blublublu");
+}
+
+TEST_F(SandboxBrokerTest, Chmod)
+{
+  PrePostTestCleanup();
+
+  int fd = Open("/tmp/blublu", O_WRONLY | O_CREAT);
+  ASSERT_GE(fd, 0) << "Opening /tmp/blublu for writing failed.";
+  close(fd);
+  // Set read only. SandboxBroker enforces 0600 mode flags.
+  ASSERT_EQ(0, Chmod("/tmp/blublu", S_IRUSR));
+  // SandboxBroker doesn't use real access(), it just checks against
+  // the policy. So it can't see the change in permisions here.
+  // This won't work:
+  // EXPECT_EQ(-EACCES, Access("/tmp/blublu", W_OK));
+  statstruct realStat;
+  EXPECT_EQ(0, statsyscall("/tmp/blublu", &realStat));
+  EXPECT_EQ((mode_t)S_IRUSR, realStat.st_mode & 0777);
+
+  ASSERT_EQ(0, Chmod("/tmp/blublu", S_IRUSR | S_IWUSR));
+  EXPECT_EQ(0, statsyscall("/tmp/blublu", &realStat));
+  EXPECT_EQ((mode_t)(S_IRUSR | S_IWUSR), realStat.st_mode & 0777);
+  EXPECT_EQ(0, unlink("/tmp/blublu"));
+
+  PrePostTestCleanup();
+}
+
+TEST_F(SandboxBrokerTest, Link)
+{
+  PrePostTestCleanup();
+
+  int fd = Open("/tmp/blublu", O_WRONLY | O_CREAT);
+  ASSERT_GE(fd, 0) << "Opening /tmp/blublu for writing failed.";
+  close(fd);
+  ASSERT_EQ(0, Link("/tmp/blublu", "/tmp/blublublu"));
+  EXPECT_EQ(0, Access("/tmp/blublublu", F_OK));
+  // Not whitelisted target path
+  EXPECT_EQ(-EACCES, Link("/tmp/blublu", "/tmp/nope"));
+  EXPECT_EQ(0, unlink("/tmp/blublublu"));
+  EXPECT_EQ(0, unlink("/tmp/blublu"));
+
+  PrePostTestCleanup();
+}
+
+TEST_F(SandboxBrokerTest, Symlink)
+{
+  PrePostTestCleanup();
+
+  int fd = Open("/tmp/blublu", O_WRONLY | O_CREAT);
+  ASSERT_GE(fd, 0) << "Opening /tmp/blublu for writing failed.";
+  close(fd);
+  ASSERT_EQ(0, Symlink("/tmp/blublu", "/tmp/blublublu"));
+  EXPECT_EQ(0, Access("/tmp/blublublu", F_OK));
+  statstruct aStat;
+  ASSERT_EQ(0, lstatsyscall("/tmp/blublublu", &aStat));
+  EXPECT_EQ((mode_t)S_IFLNK, aStat.st_mode & S_IFMT);
+  // Not whitelisted target path
+  EXPECT_EQ(-EACCES, Symlink("/tmp/blublu", "/tmp/nope"));
+  EXPECT_EQ(0, unlink("/tmp/blublublu"));
+  EXPECT_EQ(0, unlink("/tmp/blublu"));
+
+  PrePostTestCleanup();
+}
+
+TEST_F(SandboxBrokerTest, Mkdir)
+{
+  PrePostTestCleanup();
+
+  ASSERT_EQ(0, mkdir("/tmp/blublu", 0600))
+    << "Creating dir /tmp/blublu failed.";
+  EXPECT_EQ(0, Access("/tmp/blublu", F_OK));
+  // Not whitelisted target path
+  EXPECT_EQ(-EACCES, Mkdir("/tmp/nope", 0600))
+    << "Creating dir without MAY_CREATE succeed.";
+  EXPECT_EQ(0, rmdir("/tmp/blublu"));
+
+  PrePostTestCleanup();
+}
+
+TEST_F(SandboxBrokerTest, Rename)
+{
+  PrePostTestCleanup();
+
+  ASSERT_EQ(0, mkdir("/tmp/blublu", 0600))
+    << "Creating dir /tmp/blublu failed.";
+  EXPECT_EQ(0, Access("/tmp/blublu", F_OK));
+  ASSERT_EQ(0, Rename("/tmp/blublu", "/tmp/blublublu"));
+  EXPECT_EQ(0, Access("/tmp/blublublu", F_OK));
+  EXPECT_EQ(-ENOENT , Access("/tmp/blublu", F_OK));
+  // Not whitelisted target path
+  EXPECT_EQ(-EACCES, Rename("/tmp/blublublu", "/tmp/nope"))
+    << "Renaming dir without write access succeed.";
+  EXPECT_EQ(0, rmdir("/tmp/blublublu"));
+
+  PrePostTestCleanup();
+}
+
+TEST_F(SandboxBrokerTest, Rmdir)
+{
+  PrePostTestCleanup();
+
+  ASSERT_EQ(0, mkdir("/tmp/blublu", 0600))
+    << "Creating dir /tmp/blublu failed.";
+  EXPECT_EQ(0, Access("/tmp/blublu", F_OK));
+  ASSERT_EQ(0, Rmdir("/tmp/blublu"));
+  EXPECT_EQ(-ENOENT, Access("/tmp/blublu", F_OK));
+  // Bypass sandbox to create a non-deletable dir
+  ASSERT_EQ(0, mkdir("/tmp/nope", 0600));
+  EXPECT_EQ(-EACCES, Rmdir("/tmp/nope"));
+
+  PrePostTestCleanup();
+}
+
+TEST_F(SandboxBrokerTest, Unlink)
+{
+  PrePostTestCleanup();
+
+  int fd = Open("/tmp/blublu", O_WRONLY | O_CREAT);
+  ASSERT_GE(fd, 0) << "Opening /tmp/blublu for writing failed.";
+  close(fd);
+  EXPECT_EQ(0, Access("/tmp/blublu", F_OK));
+  EXPECT_EQ(0, Unlink("/tmp/blublu"));
+  EXPECT_EQ(-ENOENT , Access("/tmp/blublu", F_OK));
+  // Bypass sandbox to write a non-deletable file
+  fd = open("/tmp/nope", O_WRONLY | O_CREAT, 0600);
+  ASSERT_GE(fd, 0) << "Opening /tmp/nope for writing failed.";
+  close(fd);
+  EXPECT_EQ(-EACCES, Unlink("/tmp/nope"));
+
+  PrePostTestCleanup();
+}
+
+TEST_F(SandboxBrokerTest, Readlink)
+{
+  PrePostTestCleanup();
+
+  int fd = Open("/tmp/blublu", O_WRONLY | O_CREAT);
+  ASSERT_GE(fd, 0) << "Opening /tmp/blublu for writing failed.";
+  close(fd);
+  ASSERT_EQ(0, Symlink("/tmp/blublu", "/tmp/blublublu"));
+  EXPECT_EQ(0, Access("/tmp/blublublu", F_OK));
+  char linkBuff[256];
+  EXPECT_EQ(11, Readlink("/tmp/blublublu", linkBuff, sizeof(linkBuff)));
+  linkBuff[11] = '\0';
+  EXPECT_EQ(0, strcmp(linkBuff, "/tmp/blublu"));
+
+  PrePostTestCleanup();
+}
+
+TEST_F(SandboxBrokerTest, MultiThreadOpen) {
+  RunOnManyThreads<SandboxBrokerTest,
+                   &SandboxBrokerTest::MultiThreadOpenWorker>();
+}
+void SandboxBrokerTest::MultiThreadOpenWorker() {
+  static const int kNumLoops = 10000;
+
+  for (int i = 1; i <= kNumLoops; ++i) {
+    int nullfd = Open("/dev/null", O_RDONLY);
+    int zerofd = Open("/dev/zero", O_RDONLY);
+    ASSERT_GE(nullfd, 0) << "Loop " << i << "/" << kNumLoops;
+    ASSERT_GE(zerofd, 0) << "Loop " << i << "/" << kNumLoops;
+    char c;
+    ASSERT_EQ(0, read(nullfd, &c, 1)) << "Loop " << i << "/" << kNumLoops;
+    ASSERT_EQ(1, read(zerofd, &c, 1)) << "Loop " << i << "/" << kNumLoops;
+    ASSERT_EQ('\0', c) << "Loop " << i << "/" << kNumLoops;
+    close(nullfd);
+    close(zerofd);
+  }
+}
+
+TEST_F(SandboxBrokerTest, MultiThreadStat) {
+  RunOnManyThreads<SandboxBrokerTest,
+                   &SandboxBrokerTest::MultiThreadStatWorker>();
+}
+void SandboxBrokerTest::MultiThreadStatWorker() {
+  static const int kNumLoops = 7500;
+  statstruct nullStat, zeroStat, selfStat;
+  dev_t realNullDev, realZeroDev;
+  ino_t realSelfInode;
+
+  ASSERT_EQ(0, statsyscall("/dev/null", &nullStat)) << "Shouldn't ever fail!";
+  ASSERT_EQ(0, statsyscall("/dev/zero", &zeroStat)) << "Shouldn't ever fail!";
+  ASSERT_EQ(0, lstatsyscall("/proc/self", &selfStat)) << "Shouldn't ever fail!";
+  ASSERT_TRUE(S_ISLNK(selfStat.st_mode)) << "Shouldn't ever fail!";
+  realNullDev = nullStat.st_rdev;
+  realZeroDev = zeroStat.st_rdev;
+  realSelfInode = selfStat.st_ino;
+  for (int i = 1; i <= kNumLoops; ++i) {
+    ASSERT_EQ(0, Stat("/dev/null", &nullStat))
+      << "Loop " << i << "/" << kNumLoops;
+    ASSERT_EQ(0, Stat("/dev/zero", &zeroStat))
+      << "Loop " << i << "/" << kNumLoops;
+    ASSERT_EQ(0, LStat("/proc/self", &selfStat))
+      << "Loop " << i << "/" << kNumLoops;
+
+    ASSERT_EQ(realNullDev, nullStat.st_rdev)
+      << "Loop " << i << "/" << kNumLoops;
+    ASSERT_EQ(realZeroDev, zeroStat.st_rdev)
+      << "Loop " << i << "/" << kNumLoops;
+    ASSERT_TRUE(S_ISLNK(selfStat.st_mode))
+      << "Loop " << i << "/" << kNumLoops;
+    ASSERT_EQ(realSelfInode, selfStat.st_ino)
+      << "Loop " << i << "/" << kNumLoops;
+  }
+}
+
+#if 0
+class SandboxBrokerSigStress : public SandboxBrokerTest
+{
+  int mSigNum;
+  struct sigaction mOldAction;
+  Atomic<void*> mVoidPtr;
+
+  static void SigHandler(int aSigNum, siginfo_t* aSigInfo, void *aCtx) {
+    ASSERT_EQ(SI_QUEUE, aSigInfo->si_code);
+    SandboxBrokerSigStress* that =
+      static_cast<SandboxBrokerSigStress*>(aSigInfo->si_value.sival_ptr);
+    ASSERT_EQ(that->mSigNum, aSigNum);
+    that->DoSomething();
+  }
+
+protected:
+  Atomic<int> mTestIter;
+  sem_t mSemaphore;
+
+  void SignalThread(pthread_t aThread) {
+    union sigval sv;
+    sv.sival_ptr = this;
+    ASSERT_NE(0, mSigNum);
+    ASSERT_EQ(0, pthread_sigqueue(aThread, mSigNum, sv));
+  }
+
+  virtual void SetUp() {
+    ASSERT_EQ(0, sem_init(&mSemaphore, 0, 0));
+    mVoidPtr = nullptr;
+    mSigNum = 0;
+    for (int sigNum = SIGRTMIN; sigNum < SIGRTMAX; ++sigNum) {
+      ASSERT_EQ(0, sigaction(sigNum, nullptr, &mOldAction));
+      if ((mOldAction.sa_flags & SA_SIGINFO) == 0 &&
+          mOldAction.sa_handler == SIG_DFL) {
+        struct sigaction newAction;
+        PodZero(&newAction);
+        newAction.sa_flags = SA_SIGINFO;
+        newAction.sa_sigaction = SigHandler;
+        ASSERT_EQ(0, sigaction(sigNum, &newAction, nullptr));
+        mSigNum = sigNum;
+        break;
+      }
+    }
+    ASSERT_NE(mSigNum, 0);
+
+    SandboxBrokerTest::SetUp();
+  }
+
+  virtual void TearDown() {
+    ASSERT_EQ(0, sem_destroy(&mSemaphore));
+    if (mSigNum != 0) {
+      ASSERT_EQ(0, sigaction(mSigNum, &mOldAction, nullptr));
+    }
+    if (mVoidPtr) {
+      free(mVoidPtr);
+    }
+  }
+
+  void DoSomething();
+
+public:
+  void MallocWorker();
+  void FreeWorker();
+};
+
+TEST_F(SandboxBrokerSigStress, StressTest)
+{
+  static const int kIters = 6250;
+  static const int kNsecPerIterPerIter = 4;
+  struct timespec delay = { 0, 0 };
+  pthread_t threads[2];
+
+  mTestIter = kIters;
+
+  StartThread<SandboxBrokerSigStress,
+              &SandboxBrokerSigStress::MallocWorker>(&threads[0]);
+  StartThread<SandboxBrokerSigStress,
+              &SandboxBrokerSigStress::FreeWorker>(&threads[1]);
+
+  for (int i = kIters; i > 0; --i) {
+    SignalThread(threads[i % 2]);
+    while (sem_wait(&mSemaphore) == -1 && errno == EINTR)
+      /* retry */;
+    ASSERT_EQ(i - 1, mTestIter);
+    delay.tv_nsec += kNsecPerIterPerIter;
+    struct timespec req = delay, rem;
+    while (nanosleep(&req, &rem) == -1 && errno == EINTR) {
+      req = rem;
+    }
+  }
+  void *retval;
+  ASSERT_EQ(0, pthread_join(threads[0], &retval));
+  ASSERT_EQ(nullptr, retval);
+  ASSERT_EQ(0, pthread_join(threads[1], &retval));
+  ASSERT_EQ(nullptr, retval);
+}
+
+void
+SandboxBrokerSigStress::MallocWorker()
+{
+  static const size_t kSize = 64;
+
+  void* mem = malloc(kSize);
+  while (mTestIter > 0) {
+    ASSERT_NE(mem, mVoidPtr);
+    mem = mVoidPtr.exchange(mem);
+    if (mem) {
+      sched_yield();
+    } else {
+      mem = malloc(kSize);
+    }
+  }
+  if (mem) {
+    free(mem);
+  }
+}
+
+void
+SandboxBrokerSigStress::FreeWorker()
+{
+  void *mem = nullptr;
+  while (mTestIter > 0) {
+    mem = mVoidPtr.exchange(mem);
+    if (mem) {
+      free(mem);
+      mem = nullptr;
+    } else {
+      sched_yield();
+    }
+  }
+}
+
+void
+SandboxBrokerSigStress::DoSomething()
+{
+  int fd;
+  char c;
+  struct stat st;
+
+  //fprintf(stderr, "Don't try this at home: %d\n", static_cast<int>(mTestIter));
+  switch (mTestIter % 5) {
+  case 0:
+    fd = Open("/dev/null", O_RDWR);
+    ASSERT_GE(fd, 0);
+    ASSERT_EQ(0, read(fd, &c, 1));
+    close(fd);
+    break;
+  case 1:
+    fd = Open("/dev/zero", O_RDONLY);
+    ASSERT_GE(fd, 0);
+    ASSERT_EQ(1, read(fd, &c, 1));
+    ASSERT_EQ('\0', c);
+    close(fd);
+    break;
+  case 2:
+    ASSERT_EQ(0, Access("/dev/null", W_OK));
+    break;
+  case 3:
+    ASSERT_EQ(0, Stat("/proc/self", &st));
+    ASSERT_TRUE(S_ISDIR(st.st_mode));
+    break;
+  case 4:
+    ASSERT_EQ(0, LStat("/proc/self", &st));
+    ASSERT_TRUE(S_ISLNK(st.st_mode));
+    break;
+  }
+  mTestIter--;
+  sem_post(&mSemaphore);
+}
+#endif
+
+} // namespace mozilla