Adding upstream version 110.0.1.upstream/110.0.1upstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 578 insertions, 0 deletions

diff --git a/toolkit/profile/nsProfileLock.cpp b/toolkit/profile/nsProfileLock.cpp
new file mode 100644
index 0000000000..0a809642aa
--- /dev/null
+++ b/toolkit/profile/nsProfileLock.cpp
@@ -0,0 +1,578 @@
+/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* 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 "nsProfileLock.h"
+#include "nsCOMPtr.h"
+#include "nsQueryObject.h"
+#include "nsString.h"
+#include "nsPrintfCString.h"
+#include "nsDebug.h"
+
+#if defined(XP_WIN)
+#  include "ProfileUnlockerWin.h"
+#endif
+
+#if defined(XP_MACOSX)
+#  include <Carbon/Carbon.h>
+#  include <CoreFoundation/CoreFoundation.h>
+#endif
+
+#if defined(MOZ_WIDGET_ANDROID)
+#  include "ProfileUnlockerAndroid.h"
+#endif
+
+#ifdef XP_UNIX
+#  include <unistd.h>
+#  include <fcntl.h>
+#  include <errno.h>
+#  include <signal.h>
+#  include <stdlib.h>
+#  include "prnetdb.h"
+#  include "prsystem.h"
+#  include "prenv.h"
+#  include "mozilla/Printf.h"
+#endif
+
+// **********************************************************************
+// class nsProfileLock
+//
+// This code was moved from profile/src/nsProfileAccess.
+// **********************************************************************
+
+#if defined(XP_UNIX)
+static bool sDisableSignalHandling = false;
+#endif
+
+nsProfileLock::nsProfileLock()
+    : mHaveLock(false),
+      mReplacedLockTime(0)
+#if defined(XP_WIN)
+      ,
+      mLockFileHandle(INVALID_HANDLE_VALUE)
+#elif defined(XP_UNIX)
+      ,
+      mPidLockFileName(nullptr),
+      mLockFileDesc(-1)
+#endif
+{
+#if defined(XP_UNIX)
+  next = prev = this;
+  sDisableSignalHandling = PR_GetEnv("MOZ_DISABLE_SIG_HANDLER") ? true : false;
+#endif
+}
+
+nsProfileLock::nsProfileLock(nsProfileLock& src) { *this = src; }
+
+nsProfileLock& nsProfileLock::operator=(nsProfileLock& rhs) {
+  Unlock();
+
+  mHaveLock = rhs.mHaveLock;
+  rhs.mHaveLock = false;
+
+#if defined(XP_WIN)
+  mLockFileHandle = rhs.mLockFileHandle;
+  rhs.mLockFileHandle = INVALID_HANDLE_VALUE;
+#elif defined(XP_UNIX)
+  mLockFileDesc = rhs.mLockFileDesc;
+  rhs.mLockFileDesc = -1;
+  mPidLockFileName = rhs.mPidLockFileName;
+  rhs.mPidLockFileName = nullptr;
+  if (mPidLockFileName) {
+    // rhs had a symlink lock, therefore it was on the list.
+    PR_REMOVE_LINK(&rhs);
+    PR_APPEND_LINK(this, &mPidLockList);
+  }
+#endif
+
+  return *this;
+}
+
+nsProfileLock::~nsProfileLock() {
+  Unlock();
+  // Note that we don't clean up by default here so on next startup we know when
+  // the profile was last used based on the modification time of the lock file.
+}
+
+#if defined(XP_UNIX)
+
+static int setupPidLockCleanup;
+
+PRCList nsProfileLock::mPidLockList =
+    PR_INIT_STATIC_CLIST(&nsProfileLock::mPidLockList);
+
+void nsProfileLock::RemovePidLockFiles(bool aFatalSignal) {
+  while (!PR_CLIST_IS_EMPTY(&mPidLockList)) {
+    nsProfileLock* lock = static_cast<nsProfileLock*>(mPidLockList.next);
+    lock->Unlock(aFatalSignal);
+  }
+}
+
+static struct sigaction SIGHUP_oldact;
+static struct sigaction SIGINT_oldact;
+static struct sigaction SIGQUIT_oldact;
+static struct sigaction SIGILL_oldact;
+static struct sigaction SIGABRT_oldact;
+static struct sigaction SIGSEGV_oldact;
+static struct sigaction SIGTERM_oldact;
+
+void nsProfileLock::FatalSignalHandler(int signo
+#  ifdef SA_SIGINFO
+                                       ,
+                                       siginfo_t* info, void* context
+#  endif
+) {
+  // Remove any locks still held.
+  RemovePidLockFiles(true);
+
+  // Chain to the old handler, which may exit.
+  struct sigaction* oldact = nullptr;
+
+  switch (signo) {
+    case SIGHUP:
+      oldact = &SIGHUP_oldact;
+      break;
+    case SIGINT:
+      oldact = &SIGINT_oldact;
+      break;
+    case SIGQUIT:
+      oldact = &SIGQUIT_oldact;
+      break;
+    case SIGILL:
+      oldact = &SIGILL_oldact;
+      break;
+    case SIGABRT:
+      oldact = &SIGABRT_oldact;
+      break;
+    case SIGSEGV:
+      oldact = &SIGSEGV_oldact;
+      break;
+    case SIGTERM:
+      oldact = &SIGTERM_oldact;
+      break;
+    default:
+      MOZ_ASSERT_UNREACHABLE("bad signo");
+      break;
+  }
+
+  if (oldact) {
+    if (oldact->sa_handler == SIG_DFL) {
+      // Make sure the default sig handler is executed
+      // We need it to get Mozilla to dump core.
+      sigaction(signo, oldact, nullptr);
+
+      // Now that we've restored the default handler, unmask the
+      // signal and invoke it.
+
+      sigset_t unblock_sigs;
+      sigemptyset(&unblock_sigs);
+      sigaddset(&unblock_sigs, signo);
+
+      sigprocmask(SIG_UNBLOCK, &unblock_sigs, nullptr);
+
+      raise(signo);
+    }
+#  ifdef SA_SIGINFO
+    else if (oldact->sa_sigaction &&
+             (oldact->sa_flags & SA_SIGINFO) == SA_SIGINFO) {
+      oldact->sa_sigaction(signo, info, context);
+    }
+#  endif
+    else if (oldact->sa_handler && oldact->sa_handler != SIG_IGN) {
+      oldact->sa_handler(signo);
+    }
+  }
+
+  // Backstop exit call, just in case.
+  _exit(signo);
+}
+
+nsresult nsProfileLock::LockWithFcntl(nsIFile* aLockFile,
+                                      nsIProfileUnlocker** aUnlocker) {
+  nsresult rv = NS_OK;
+
+  nsAutoCString lockFilePath;
+  rv = aLockFile->GetNativePath(lockFilePath);
+  if (NS_FAILED(rv)) {
+    NS_ERROR("Could not get native path");
+    return rv;
+  }
+
+  aLockFile->GetLastModifiedTime(&mReplacedLockTime);
+
+  mLockFileDesc = open(lockFilePath.get(), O_WRONLY | O_CREAT | O_TRUNC, 0666);
+  if (mLockFileDesc != -1) {
+    struct flock lock;
+    lock.l_start = 0;
+    lock.l_len = 0;  // len = 0 means entire file
+    lock.l_type = F_WRLCK;
+    lock.l_whence = SEEK_SET;
+
+    // If fcntl(F_GETLK) fails then the server does not support/allow fcntl(),
+    // return failure rather than access denied in this case so we fallback
+    // to using a symlink lock, bug 303633.
+    struct flock testlock = lock;
+    if (fcntl(mLockFileDesc, F_GETLK, &testlock) == -1) {
+      close(mLockFileDesc);
+      mLockFileDesc = -1;
+      rv = NS_ERROR_FAILURE;
+    } else if (fcntl(mLockFileDesc, F_SETLK, &lock) == -1) {
+#  ifdef MOZ_WIDGET_ANDROID
+      MOZ_ASSERT(aUnlocker);
+      RefPtr<mozilla::ProfileUnlockerAndroid> unlocker(
+          new mozilla::ProfileUnlockerAndroid(testlock.l_pid));
+      nsCOMPtr<nsIProfileUnlocker> unlockerInterface(do_QueryObject(unlocker));
+      unlockerInterface.forget(aUnlocker);
+#  endif
+
+      close(mLockFileDesc);
+      mLockFileDesc = -1;
+
+      // With OS X, on NFS, errno == ENOTSUP
+      // XXX Check for that and return specific rv for it?
+#  ifdef DEBUG
+      printf("fcntl(F_SETLK) failed. errno = %d\n", errno);
+#  endif
+      if (errno == EAGAIN || errno == EACCES)
+        rv = NS_ERROR_FILE_ACCESS_DENIED;
+      else
+        rv = NS_ERROR_FAILURE;
+    }
+  } else {
+    NS_ERROR("Failed to open lock file.");
+    rv = NS_ERROR_FAILURE;
+  }
+  return rv;
+}
+
+static bool IsSymlinkStaleLock(struct in_addr* aAddr, const char* aFileName,
+                               bool aHaveFcntlLock) {
+  // the link exists; see if it's from this machine, and if
+  // so if the process is still active
+  char buf[1024];
+  int len = readlink(aFileName, buf, sizeof buf - 1);
+  if (len > 0) {
+    buf[len] = '\0';
+    char* colon = strchr(buf, ':');
+    if (colon) {
+      *colon++ = '\0';
+      unsigned long addr = inet_addr(buf);
+      if (addr != (unsigned long)-1) {
+        if (colon[0] == '+' && aHaveFcntlLock) {
+          // This lock was placed by a Firefox build which would have
+          // taken the fnctl lock, and we've already taken the fcntl lock,
+          // so the process that created this obsolete lock must be gone
+          return true;
+        }
+
+        char* after = nullptr;
+        pid_t pid = strtol(colon, &after, 0);
+        if (pid != 0 && *after == '\0') {
+          if (addr != aAddr->s_addr) {
+            // Remote lock: give up even if stuck.
+            return false;
+          }
+
+          // kill(pid,0) is a neat trick to check if a
+          // process exists
+          if (kill(pid, 0) == 0 || errno != ESRCH) {
+            // Local process appears to be alive, ass-u-me it
+            // is another Mozilla instance, or a compatible
+            // derivative, that's currently using the profile.
+            // XXX need an "are you Mozilla?" protocol
+            return false;
+          }
+        }
+      }
+    }
+  }
+  return true;
+}
+
+nsresult nsProfileLock::LockWithSymlink(nsIFile* aLockFile,
+                                        bool aHaveFcntlLock) {
+  nsresult rv;
+  nsAutoCString lockFilePath;
+  rv = aLockFile->GetNativePath(lockFilePath);
+  if (NS_FAILED(rv)) {
+    NS_ERROR("Could not get native path");
+    return rv;
+  }
+
+  // don't replace an existing lock time if fcntl already got one
+  if (!mReplacedLockTime)
+    aLockFile->GetLastModifiedTimeOfLink(&mReplacedLockTime);
+
+  struct in_addr inaddr;
+  inaddr.s_addr = htonl(INADDR_LOOPBACK);
+
+  // We still have not loaded the profile, so we may not have proxy information.
+  // Avoiding a DNS lookup in this stage makes sure any proxy is not bypassed.
+  // By default, the lookup is enabled, but when it is not, we use 127.0.0.1
+  // for the IP address portion of the lock signature.
+  // However, this may cause the browser to refuse to start in the rare case
+  // that all of the following conditions are met:
+  //   1. The browser profile is on a network file system.
+  //   2. The file system does not support fcntl() locking.
+  //   3. The browser is run from two different computers at the same time.
+#  ifndef MOZ_PROXY_BYPASS_PROTECTION
+  char hostname[256];
+  PRStatus status = PR_GetSystemInfo(PR_SI_HOSTNAME, hostname, sizeof hostname);
+  if (status == PR_SUCCESS) {
+    char netdbbuf[PR_NETDB_BUF_SIZE];
+    PRHostEnt hostent;
+    status = PR_GetHostByName(hostname, netdbbuf, sizeof netdbbuf, &hostent);
+    if (status == PR_SUCCESS) memcpy(&inaddr, hostent.h_addr, sizeof inaddr);
+  }
+#  endif
+
+  mozilla::SmprintfPointer signature =
+      mozilla::Smprintf("%s:%s%lu", inet_ntoa(inaddr),
+                        aHaveFcntlLock ? "+" : "", (unsigned long)getpid());
+  const char* fileName = lockFilePath.get();
+  int symlink_rv, symlink_errno = 0, tries = 0;
+
+  // use ns4.x-compatible symlinks if the FS supports them
+  while ((symlink_rv = symlink(signature.get(), fileName)) < 0) {
+    symlink_errno = errno;
+    if (symlink_errno != EEXIST) break;
+
+    if (!IsSymlinkStaleLock(&inaddr, fileName, aHaveFcntlLock)) break;
+
+    // Lock seems to be bogus: try to claim it.  Give up after a large
+    // number of attempts (100 comes from the 4.x codebase).
+    (void)unlink(fileName);
+    if (++tries > 100) break;
+  }
+
+  if (symlink_rv == 0) {
+    // We exclusively created the symlink: record its name for eventual
+    // unlock-via-unlink.
+    rv = NS_OK;
+    mPidLockFileName = strdup(fileName);
+    if (mPidLockFileName) {
+      PR_APPEND_LINK(this, &mPidLockList);
+      if (!setupPidLockCleanup++) {
+        // Clean up on normal termination.
+        // This instanciates a dummy class, and will trigger the class
+        // destructor when libxul is unloaded. This is equivalent to atexit(),
+        // but gracefully handles dlclose().
+        static RemovePidLockFilesExiting r;
+
+        // Clean up on abnormal termination, using POSIX sigaction.
+        // Don't arm a handler if the signal is being ignored, e.g.,
+        // because mozilla is run via nohup.
+        if (!sDisableSignalHandling) {
+          struct sigaction act, oldact;
+#  ifdef SA_SIGINFO
+          act.sa_sigaction = FatalSignalHandler;
+          act.sa_flags = SA_SIGINFO | SA_ONSTACK;
+#  else
+          act.sa_handler = FatalSignalHandler;
+#  endif
+          sigfillset(&act.sa_mask);
+
+#  define CATCH_SIGNAL(signame)                      \
+    PR_BEGIN_MACRO                                   \
+    if (sigaction(signame, nullptr, &oldact) == 0 && \
+        oldact.sa_handler != SIG_IGN) {              \
+      sigaction(signame, &act, &signame##_oldact);   \
+    }                                                \
+    PR_END_MACRO
+
+          CATCH_SIGNAL(SIGHUP);
+          CATCH_SIGNAL(SIGINT);
+          CATCH_SIGNAL(SIGQUIT);
+          CATCH_SIGNAL(SIGILL);
+          CATCH_SIGNAL(SIGABRT);
+          CATCH_SIGNAL(SIGSEGV);
+          CATCH_SIGNAL(SIGTERM);
+
+#  undef CATCH_SIGNAL
+        }
+      }
+    }
+  } else if (symlink_errno == EEXIST)
+    rv = NS_ERROR_FILE_ACCESS_DENIED;
+  else {
+#  ifdef DEBUG
+    printf("symlink() failed. errno = %d\n", errno);
+#  endif
+    rv = NS_ERROR_FAILURE;
+  }
+  return rv;
+}
+#endif /* XP_UNIX */
+
+nsresult nsProfileLock::GetReplacedLockTime(PRTime* aResult) {
+  *aResult = mReplacedLockTime;
+  return NS_OK;
+}
+
+#if defined(XP_MACOSX)
+constexpr auto LOCKFILE_NAME = u".parentlock"_ns;
+constexpr auto OLD_LOCKFILE_NAME = u"parent.lock"_ns;
+#elif defined(XP_UNIX)
+constexpr auto OLD_LOCKFILE_NAME = u"lock"_ns;
+constexpr auto LOCKFILE_NAME = u".parentlock"_ns;
+#else
+constexpr auto LOCKFILE_NAME = u"parent.lock"_ns;
+#endif
+
+bool nsProfileLock::IsMaybeLockFile(nsIFile* aFile) {
+  nsAutoString tmp;
+  if (NS_SUCCEEDED(aFile->GetLeafName(tmp))) {
+    if (tmp.Equals(LOCKFILE_NAME)) return true;
+#if (defined(XP_MACOSX) || defined(XP_UNIX))
+    if (tmp.Equals(OLD_LOCKFILE_NAME)) return true;
+#endif
+  }
+  return false;
+}
+
+nsresult nsProfileLock::Lock(nsIFile* aProfileDir,
+                             nsIProfileUnlocker** aUnlocker) {
+  nsresult rv;
+  if (aUnlocker) *aUnlocker = nullptr;
+
+  NS_ENSURE_STATE(!mHaveLock);
+
+  bool isDir;
+  rv = aProfileDir->IsDirectory(&isDir);
+  if (NS_FAILED(rv)) return rv;
+  if (!isDir) return NS_ERROR_FILE_NOT_DIRECTORY;
+
+  nsCOMPtr<nsIFile> lockFile;
+  rv = aProfileDir->Clone(getter_AddRefs(lockFile));
+  if (NS_FAILED(rv)) return rv;
+
+  rv = lockFile->Append(LOCKFILE_NAME);
+  if (NS_FAILED(rv)) return rv;
+
+  // Remember the name we're using so we can clean up
+  rv = lockFile->Clone(getter_AddRefs(mLockFile));
+  if (NS_FAILED(rv)) return rv;
+
+#if defined(XP_MACOSX)
+  // First, try locking using fcntl. It is more reliable on
+  // a local machine, but may not be supported by an NFS server.
+
+  rv = LockWithFcntl(lockFile);
+  if (NS_FAILED(rv) && (rv != NS_ERROR_FILE_ACCESS_DENIED)) {
+    // If that failed for any reason other than NS_ERROR_FILE_ACCESS_DENIED,
+    // assume we tried an NFS that does not support it. Now, try with symlink.
+    rv = LockWithSymlink(lockFile, false);
+  }
+#elif defined(XP_UNIX)
+  // Get the old lockfile name
+  nsCOMPtr<nsIFile> oldLockFile;
+  rv = aProfileDir->Clone(getter_AddRefs(oldLockFile));
+  if (NS_FAILED(rv)) return rv;
+  rv = oldLockFile->Append(OLD_LOCKFILE_NAME);
+  if (NS_FAILED(rv)) return rv;
+
+  // First, try locking using fcntl. It is more reliable on
+  // a local machine, but may not be supported by an NFS server.
+  rv = LockWithFcntl(lockFile, aUnlocker);
+  if (NS_SUCCEEDED(rv)) {
+    // Check to see whether there is a symlink lock held by an older
+    // Firefox build, and also place our own symlink lock --- but
+    // mark it "obsolete" so that other newer builds can break the lock
+    // if they obtain the fcntl lock
+    rv = LockWithSymlink(oldLockFile, true);
+
+    // If the symlink failed for some reason other than it already
+    // exists, then something went wrong e.g. the file system
+    // doesn't support symlinks, or we don't have permission to
+    // create a symlink there.  In such cases we should just
+    // continue because it's unlikely there is an old build
+    // running with a symlink there and we've already successfully
+    // placed a fcntl lock.
+    if (rv != NS_ERROR_FILE_ACCESS_DENIED) rv = NS_OK;
+  } else if (rv != NS_ERROR_FILE_ACCESS_DENIED) {
+    // If that failed for any reason other than NS_ERROR_FILE_ACCESS_DENIED,
+    // assume we tried an NFS that does not support it. Now, try with symlink
+    // using the old symlink path
+    rv = LockWithSymlink(oldLockFile, false);
+  }
+
+#elif defined(XP_WIN)
+  nsAutoString filePath;
+  rv = lockFile->GetPath(filePath);
+  if (NS_FAILED(rv)) return rv;
+
+  lockFile->GetLastModifiedTime(&mReplacedLockTime);
+
+  // always create the profile lock and never delete it so we can use its
+  // modification timestamp to detect startup crashes
+  mLockFileHandle = CreateFileW(filePath.get(), GENERIC_READ | GENERIC_WRITE,
+                                0,  // no sharing - of course
+                                nullptr, CREATE_ALWAYS, 0, nullptr);
+  if (mLockFileHandle == INVALID_HANDLE_VALUE) {
+    if (aUnlocker) {
+      RefPtr<mozilla::ProfileUnlockerWin> unlocker(
+          new mozilla::ProfileUnlockerWin(filePath));
+      if (NS_SUCCEEDED(unlocker->Init())) {
+        nsCOMPtr<nsIProfileUnlocker> unlockerInterface(
+            do_QueryObject(unlocker));
+        unlockerInterface.forget(aUnlocker);
+      }
+    }
+    return NS_ERROR_FILE_ACCESS_DENIED;
+  }
+#endif
+
+  if (NS_SUCCEEDED(rv)) mHaveLock = true;
+
+  return rv;
+}
+
+nsresult nsProfileLock::Unlock(bool aFatalSignal) {
+  nsresult rv = NS_OK;
+
+  if (mHaveLock) {
+#if defined(XP_WIN)
+    if (mLockFileHandle != INVALID_HANDLE_VALUE) {
+      CloseHandle(mLockFileHandle);
+      mLockFileHandle = INVALID_HANDLE_VALUE;
+    }
+#elif defined(XP_UNIX)
+    if (mPidLockFileName) {
+      PR_REMOVE_LINK(this);
+      (void)unlink(mPidLockFileName);
+
+      // Only free mPidLockFileName if we're not in the fatal signal
+      // handler.  The problem is that a call to free() might be the
+      // cause of this fatal signal.  If so, calling free() might cause
+      // us to wait on the malloc implementation's lock.  We're already
+      // holding this lock, so we'll deadlock. See bug 522332.
+      if (!aFatalSignal) free(mPidLockFileName);
+      mPidLockFileName = nullptr;
+    }
+    if (mLockFileDesc != -1) {
+      close(mLockFileDesc);
+      mLockFileDesc = -1;
+      // Don't remove it
+    }
+#endif
+
+    mHaveLock = false;
+  }
+
+  return rv;
+}
+
+nsresult nsProfileLock::Cleanup() {
+  if (mHaveLock) {
+    return NS_ERROR_FILE_IS_LOCKED;
+  }
+
+  if (mLockFile) {
+    nsresult rv = mLockFile->Remove(false);
+    NS_ENSURE_SUCCESS(rv, rv);
+    mLockFile = nullptr;
+  }
+
+  return NS_OK;
+}