Adding upstream version 115.7.0esr.upstream/115.7.0esrupstream

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

1 files changed, 1017 insertions, 0 deletions

diff --git a/security/sandbox/linux/broker/SandboxBrokerPolicyFactory.cpp b/security/sandbox/linux/broker/SandboxBrokerPolicyFactory.cpp
new file mode 100644
index 0000000000..fe7ce56c7e
--- /dev/null
+++ b/security/sandbox/linux/broker/SandboxBrokerPolicyFactory.cpp
@@ -0,0 +1,1017 @@
+/* -*- 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 "SandboxBrokerPolicyFactory.h"
+#include "SandboxInfo.h"
+#include "SandboxLogging.h"
+
+#include "base/shared_memory.h"
+#include "mozilla/Array.h"
+#include "mozilla/ClearOnShutdown.h"
+#include "mozilla/Omnijar.h"
+#include "mozilla/Preferences.h"
+#include "mozilla/SandboxLaunch.h"
+#include "mozilla/SandboxSettings.h"
+#include "mozilla/StaticPrefs_security.h"
+#include "mozilla/StaticMutex.h"
+#include "mozilla/UniquePtr.h"
+#include "mozilla/UniquePtrExtensions.h"
+#include "nsComponentManagerUtils.h"
+#include "nsPrintfCString.h"
+#include "nsString.h"
+#include "nsThreadUtils.h"
+#include "nsXULAppAPI.h"
+#include "nsDirectoryServiceDefs.h"
+#include "nsAppDirectoryServiceDefs.h"
+#include "SpecialSystemDirectory.h"
+#include "nsReadableUtils.h"
+#include "nsIFileStreams.h"
+#include "nsILineInputStream.h"
+#include "nsIFile.h"
+
+#include "nsNetCID.h"
+#include "prenv.h"
+
+#ifdef ANDROID
+#  include "cutils/properties.h"
+#endif
+
+#ifdef MOZ_WIDGET_GTK
+#  include "mozilla/WidgetUtilsGtk.h"
+#  include <glib.h>
+#endif
+
+#include <dirent.h>
+#include <sys/stat.h>
+#include <sys/sysmacros.h>
+#include <sys/types.h>
+#ifndef ANDROID
+#  include <glob.h>
+#endif
+
+namespace mozilla {
+
+namespace {
+static const int rdonly = SandboxBroker::MAY_READ;
+static const int wronly = SandboxBroker::MAY_WRITE;
+static const int rdwr = rdonly | wronly;
+static const int rdwrcr = rdwr | SandboxBroker::MAY_CREATE;
+static const int access = SandboxBroker::MAY_ACCESS;
+static const int deny = SandboxBroker::FORCE_DENY;
+}  // namespace
+
+using CacheE = std::pair<nsCString, int>;
+using FileCacheT = nsTArray<CacheE>;
+
+static void AddDriPaths(SandboxBroker::Policy* aPolicy) {
+  // Bug 1401666: Mesa driver loader part 2: Mesa <= 12 using libudev
+  // Used by libdrm, which is used by Mesa, and
+  // Intel(R) Media Driver for VAAPI.
+  if (auto dir = opendir("/dev/dri")) {
+    while (auto entry = readdir(dir)) {
+      if (entry->d_name[0] != '.') {
+        nsPrintfCString devPath("/dev/dri/%s", entry->d_name);
+        struct stat sb;
+        if (stat(devPath.get(), &sb) == 0 && S_ISCHR(sb.st_mode)) {
+          // For both the DRI node and its parent (the physical
+          // device), allow reading the "uevent" file.
+          static const Array<nsCString, 2> kSuffixes = {""_ns, "/device"_ns};
+          nsPrintfCString prefix("/sys/dev/char/%u:%u", major(sb.st_rdev),
+                                 minor(sb.st_rdev));
+          for (const auto& suffix : kSuffixes) {
+            nsCString sysPath(prefix + suffix);
+
+            // libudev will expand the symlink but not do full
+            // canonicalization, so it will leave in ".." path
+            // components that will be realpath()ed in the
+            // broker.  To match this, allow the canonical paths.
+            UniqueFreePtr<char[]> realSysPath(realpath(sysPath.get(), nullptr));
+            if (realSysPath) {
+              // https://gitlab.freedesktop.org/mesa/drm/-/commit/3988580e4c0f4b3647a0c6af138a3825453fe6e0
+              // > term = strrchr(real_path, '/');
+              // > if (term && strncmp(term, "/virtio", 7) == 0)
+              // >     *term = 0;
+              char* term = strrchr(realSysPath.get(), '/');
+              if (term && strncmp(term, "/virtio", 7) == 0) {
+                *term = 0;
+              }
+
+              aPolicy->AddFilePrefix(rdonly, realSysPath.get(), "");
+              // Allowing stat-ing and readlink-ing the parent dirs
+              nsPrintfCString basePath("%s/", realSysPath.get());
+              aPolicy->AddAncestors(basePath.get(), rdonly);
+            }
+          }
+
+          // https://gitlab.freedesktop.org/mesa/drm/-/commit/a02900133b32dd4a7d6da4966f455ab337e80dfc
+          // > strncpy(path, device_path, PATH_MAX);
+          // > strncat(path, "/subsystem", PATH_MAX);
+          // >
+          // > if (readlink(path, link, PATH_MAX) < 0)
+          // >     return -errno;
+          nsCString subsystemPath(prefix + "/device/subsystem"_ns);
+          aPolicy->AddPath(rdonly, subsystemPath.get());
+          aPolicy->AddAncestors(subsystemPath.get(), rdonly);
+        }
+      }
+    }
+    closedir(dir);
+  }
+
+  // https://gitlab.freedesktop.org/mesa/mesa/-/commit/04bdbbcab3c4862bf3f54ce60fcc1d2007776f80
+  aPolicy->AddPath(rdonly, "/usr/share/drirc.d");
+
+  // https://dri.freedesktop.org/wiki/ConfigurationInfrastructure/
+  aPolicy->AddPath(rdonly, "/etc/drirc");
+
+  nsCOMPtr<nsIFile> drirc;
+  nsresult rv =
+      GetSpecialSystemDirectory(Unix_HomeDirectory, getter_AddRefs(drirc));
+  if (NS_SUCCEEDED(rv)) {
+    rv = drirc->AppendNative(".drirc"_ns);
+    if (NS_SUCCEEDED(rv)) {
+      nsAutoCString tmpPath;
+      rv = drirc->GetNativePath(tmpPath);
+      if (NS_SUCCEEDED(rv)) {
+        aPolicy->AddPath(rdonly, tmpPath.get());
+      }
+    }
+  }
+}
+
+static void JoinPathIfRelative(const nsACString& aCwd, const nsACString& inPath,
+                               nsACString& outPath) {
+  if (inPath.Length() < 1) {
+    outPath.Assign(aCwd);
+    SANDBOX_LOG("Unjoinable path: %s", PromiseFlatCString(aCwd).get());
+    return;
+  }
+  const char* startChar = inPath.BeginReading();
+  if (*startChar != '/') {
+    // Relative path, copy basepath in front
+    outPath.Assign(aCwd);
+    outPath.Append("/");
+    outPath.Append(inPath);
+  } else {
+    // Absolute path, it's ok like this
+    outPath.Assign(inPath);
+  }
+}
+
+static void CachePathsFromFile(FileCacheT& aCache, const nsACString& aPath);
+
+static void CachePathsFromFileInternal(FileCacheT& aCache,
+                                       const nsACString& aCwd,
+                                       const nsACString& aPath) {
+  nsresult rv;
+  nsCOMPtr<nsIFile> ldconfig(do_CreateInstance(NS_LOCAL_FILE_CONTRACTID, &rv));
+  if (NS_FAILED(rv)) {
+    return;
+  }
+  rv = ldconfig->InitWithNativePath(aPath);
+  if (NS_WARN_IF(NS_FAILED(rv))) {
+    return;
+  }
+  nsCOMPtr<nsIFileInputStream> fileStream(
+      do_CreateInstance(NS_LOCALFILEINPUTSTREAM_CONTRACTID, &rv));
+  if (NS_WARN_IF(NS_FAILED(rv))) {
+    return;
+  }
+  rv = fileStream->Init(ldconfig, -1, -1, 0);
+  if (NS_WARN_IF(NS_FAILED(rv))) {
+    return;
+  }
+  nsCOMPtr<nsILineInputStream> lineStream(do_QueryInterface(fileStream, &rv));
+  if (NS_WARN_IF(NS_FAILED(rv))) {
+    return;
+  }
+
+  nsAutoCString line;
+  bool more = true;
+  do {
+    rv = lineStream->ReadLine(line, &more);
+    if (NS_FAILED(rv)) {
+      break;
+    }
+    // Cut off any comments at the end of the line, also catches lines
+    // that are entirely a comment
+    int32_t hash = line.FindChar('#');
+    if (hash >= 0) {
+      line = Substring(line, 0, hash);
+    }
+    // Simplify our following parsing by trimming whitespace
+    line.CompressWhitespace(true, true);
+    if (line.IsEmpty()) {
+      // Skip comment lines
+      continue;
+    }
+    // Check for any included files and recursively process
+    nsACString::const_iterator start, end, token_end;
+
+    line.BeginReading(start);
+    line.EndReading(end);
+    token_end = end;
+
+    if (FindInReadable("include "_ns, start, token_end)) {
+      nsAutoCString includes(Substring(token_end, end));
+      for (const nsACString& includeGlob : includes.Split(' ')) {
+        // Glob path might be relative, so add cwd if so.
+        nsAutoCString includeFile;
+        JoinPathIfRelative(aCwd, includeGlob, includeFile);
+        glob_t globbuf;
+        if (!glob(PromiseFlatCString(includeFile).get(), GLOB_NOSORT, nullptr,
+                  &globbuf)) {
+          for (size_t fileIdx = 0; fileIdx < globbuf.gl_pathc; fileIdx++) {
+            nsAutoCString filePath(globbuf.gl_pathv[fileIdx]);
+            CachePathsFromFile(aCache, filePath);
+          }
+          globfree(&globbuf);
+        }
+      }
+    }
+
+    // Cut off anything behind an = sign, used by dirname=TYPE directives
+    int32_t equals = line.FindChar('=');
+    if (equals >= 0) {
+      line = Substring(line, 0, equals);
+    }
+    char* resolvedPath = realpath(line.get(), nullptr);
+    if (resolvedPath) {
+      aCache.AppendElement(std::make_pair(nsCString(resolvedPath), rdonly));
+      free(resolvedPath);
+    }
+  } while (more);
+}
+
+static void CachePathsFromFile(FileCacheT& aCache, const nsACString& aPath) {
+  // Find the new base path where that file sits in.
+  nsresult rv;
+  nsCOMPtr<nsIFile> includeFile(
+      do_CreateInstance(NS_LOCAL_FILE_CONTRACTID, &rv));
+  if (NS_FAILED(rv)) {
+    return;
+  }
+  rv = includeFile->InitWithNativePath(aPath);
+  if (NS_WARN_IF(NS_FAILED(rv))) {
+    return;
+  }
+  if (SandboxInfo::Get().Test(SandboxInfo::kVerbose)) {
+    SANDBOX_LOG("Adding paths from %s to policy.",
+                PromiseFlatCString(aPath).get());
+  }
+
+  // Find the parent dir where this file sits in.
+  nsCOMPtr<nsIFile> parentDir;
+  rv = includeFile->GetParent(getter_AddRefs(parentDir));
+  if (NS_WARN_IF(NS_FAILED(rv))) {
+    return;
+  }
+  nsAutoCString parentPath;
+  rv = parentDir->GetNativePath(parentPath);
+  if (NS_WARN_IF(NS_FAILED(rv))) {
+    return;
+  }
+  if (SandboxInfo::Get().Test(SandboxInfo::kVerbose)) {
+    SANDBOX_LOG("Parent path is %s", PromiseFlatCString(parentPath).get());
+  }
+  CachePathsFromFileInternal(aCache, parentPath, aPath);
+}
+
+static void AddLdconfigPaths(SandboxBroker::Policy* aPolicy) {
+  static StaticMutex sMutex;
+  StaticMutexAutoLock lock(sMutex);
+
+  static FileCacheT ldConfigCache{};
+  static bool ldConfigCachePopulated = false;
+  if (!ldConfigCachePopulated) {
+    CachePathsFromFile(ldConfigCache, "/etc/ld.so.conf"_ns);
+    ldConfigCachePopulated = true;
+    RunOnShutdown([&] {
+      ldConfigCache.Clear();
+      MOZ_ASSERT(ldConfigCache.IsEmpty(), "ldconfig cache should be empty");
+    });
+  }
+  for (const CacheE& e : ldConfigCache) {
+    aPolicy->AddDir(e.second, e.first.get());
+  }
+}
+
+static void AddLdLibraryEnvPaths(SandboxBroker::Policy* aPolicy) {
+  nsAutoCString LdLibraryEnv(PR_GetEnv("LD_LIBRARY_PATH"));
+  // The items in LD_LIBRARY_PATH can be separated by either colons or
+  // semicolons, according to the ld.so(8) man page, and empirically it
+  // seems to be allowed to mix them (i.e., a:b;c is a list with 3 elements).
+  // There is no support for escaping the delimiters, fortunately (for us).
+  LdLibraryEnv.ReplaceChar(';', ':');
+  for (const nsACString& libPath : LdLibraryEnv.Split(':')) {
+    char* resolvedPath = realpath(PromiseFlatCString(libPath).get(), nullptr);
+    if (resolvedPath) {
+      aPolicy->AddDir(rdonly, resolvedPath);
+      free(resolvedPath);
+    }
+  }
+}
+
+static void AddSharedMemoryPaths(SandboxBroker::Policy* aPolicy, pid_t aPid) {
+  std::string shmPath("/dev/shm");
+  if (base::SharedMemory::AppendPosixShmPrefix(&shmPath, aPid)) {
+    aPolicy->AddPrefix(rdwrcr, shmPath.c_str());
+  }
+}
+
+static void AddMemoryReporting(SandboxBroker::Policy* aPolicy, pid_t aPid) {
+  // Bug 1198552: memory reporting.
+  // Bug 1647957: memory reporting.
+  aPolicy->AddPath(rdonly, nsPrintfCString("/proc/%d/statm", aPid).get());
+  aPolicy->AddPath(rdonly, nsPrintfCString("/proc/%d/smaps", aPid).get());
+}
+
+static void AddDynamicPathList(SandboxBroker::Policy* policy,
+                               const char* aPathListPref, int perms) {
+  nsAutoCString pathList;
+  nsresult rv = Preferences::GetCString(aPathListPref, pathList);
+  if (NS_SUCCEEDED(rv)) {
+    for (const nsACString& path : pathList.Split(',')) {
+      nsCString trimPath(path);
+      trimPath.Trim(" ", true, true);
+      policy->AddDynamic(perms, trimPath.get());
+    }
+  }
+}
+
+static void AddX11Dependencies(SandboxBroker::Policy* policy) {
+  // Allow Primus to contact the Bumblebee daemon to manage GPU
+  // switching on NVIDIA Optimus systems.
+  const char* bumblebeeSocket = PR_GetEnv("BUMBLEBEE_SOCKET");
+  if (bumblebeeSocket == nullptr) {
+    bumblebeeSocket = "/var/run/bumblebee.socket";
+  }
+  policy->AddPath(SandboxBroker::MAY_CONNECT, bumblebeeSocket);
+
+#if defined(MOZ_WIDGET_GTK) && defined(MOZ_X11)
+  // Allow local X11 connections, for several purposes:
+  //
+  // * for content processes to use WebGL when the browser is in headless
+  //   mode, by opening the X display if/when needed
+  //
+  // * if Primus or VirtualGL is used, to contact the secondary X server
+  static const bool kIsX11 =
+      !mozilla::widget::GdkIsWaylandDisplay() && PR_GetEnv("DISPLAY");
+  if (kIsX11) {
+    policy->AddPrefix(SandboxBroker::MAY_CONNECT, "/tmp/.X11-unix/X");
+    if (auto* const xauth = PR_GetEnv("XAUTHORITY")) {
+      policy->AddPath(rdonly, xauth);
+    } else if (auto* const home = PR_GetEnv("HOME")) {
+      // This follows the logic in libXau: append "/.Xauthority",
+      // even if $HOME ends in a slash, except in the special case
+      // where HOME=/ because POSIX allows implementations to treat
+      // an initial double slash specially.
+      nsAutoCString xauth(home);
+      if (xauth != "/"_ns) {
+        xauth.Append('/');
+      }
+      xauth.AppendLiteral(".Xauthority");
+      policy->AddPath(rdonly, xauth.get());
+    }
+  }
+#endif
+}
+
+static void AddGLDependencies(SandboxBroker::Policy* policy) {
+  // Devices
+  policy->AddDir(rdwr, "/dev/dri");
+  policy->AddFilePrefix(rdwr, "/dev", "nvidia");
+
+  // Hardware info
+  AddDriPaths(policy);
+
+  // /etc and /usr/share (glvnd, libdrm, drirc, ...?)
+  policy->AddDir(rdonly, "/etc");
+  policy->AddDir(rdonly, "/usr/share");
+  policy->AddDir(rdonly, "/usr/local/share");
+
+  // Snap puts the usual /usr/share things in a different place, and
+  // we'll fail to load the library if we don't have (at least) the
+  // glvnd config:
+  if (const char* snapDesktopDir = PR_GetEnv("SNAP_DESKTOP_RUNTIME")) {
+    nsAutoCString snapDesktopShare(snapDesktopDir);
+    snapDesktopShare.AppendLiteral("/usr/share");
+    policy->AddDir(rdonly, snapDesktopShare.get());
+  }
+
+  // Note: This function doesn't do anything about Mesa's shader
+  // cache, because the details can vary by process type, including
+  // whether caching is enabled.
+
+  // This also doesn't include permissions for connecting to a display
+  // server, because headless GL (e.g., Mesa GBM) may not need it.
+}
+
+void SandboxBrokerPolicyFactory::InitContentPolicy() {
+  const bool headless =
+      StaticPrefs::security_sandbox_content_headless_AtStartup();
+
+  // Policy entries that are the same in every process go here, and
+  // are cached over the lifetime of the factory.
+  SandboxBroker::Policy* policy = new SandboxBroker::Policy;
+  // Write permssions
+
+  // Bug 1575985: WASM library sandbox needs RW access to /dev/null
+  policy->AddPath(rdwr, "/dev/null");
+
+  if (!headless) {
+    AddGLDependencies(policy);
+    AddX11Dependencies(policy);
+  }
+
+  // Read permissions
+  policy->AddPath(rdonly, "/dev/urandom");
+  policy->AddPath(rdonly, "/dev/random");
+  policy->AddPath(rdonly, "/proc/sys/crypto/fips_enabled");
+  policy->AddPath(rdonly, "/proc/cpuinfo");
+  policy->AddPath(rdonly, "/proc/meminfo");
+  policy->AddDir(rdonly, "/sys/devices/cpu");
+  policy->AddDir(rdonly, "/sys/devices/system/cpu");
+  policy->AddDir(rdonly, "/lib");
+  policy->AddDir(rdonly, "/lib64");
+  policy->AddDir(rdonly, "/usr/lib");
+  policy->AddDir(rdonly, "/usr/lib32");
+  policy->AddDir(rdonly, "/usr/lib64");
+  policy->AddDir(rdonly, "/etc");
+  policy->AddDir(rdonly, "/usr/share");
+  policy->AddDir(rdonly, "/usr/local/share");
+  // Various places where fonts reside
+  policy->AddDir(rdonly, "/usr/X11R6/lib/X11/fonts");
+  policy->AddDir(rdonly, "/nix/store");
+  // https://gitlab.com/freedesktop-sdk/freedesktop-sdk/-/blob/e434e680d22260f277f4a30ec4660ed32b591d16/files/fontconfig-flatpak.conf
+  policy->AddDir(rdonly, "/run/host/fonts");
+  policy->AddDir(rdonly, "/run/host/user-fonts");
+  policy->AddDir(rdonly, "/run/host/local-fonts");
+  policy->AddDir(rdonly, "/var/cache/fontconfig");
+
+  // Bug 1848615
+  policy->AddPath(rdonly, "/usr");
+  policy->AddPath(rdonly, "/nix");
+
+  AddLdconfigPaths(policy);
+  AddLdLibraryEnvPaths(policy);
+
+  if (!headless) {
+    // Bug 1385715: NVIDIA PRIME support
+    policy->AddPath(rdonly, "/proc/modules");
+  }
+
+  // XDG directories might be non existent according to specs:
+  // https://specifications.freedesktop.org/basedir-spec/0.8/ar01s04.html
+  //
+  // > If, when attempting to write a file, the destination directory is
+  // > non-existent an attempt should be made to create it with permission 0700.
+  //
+  // For that we use AddPath(, SandboxBroker::Policy::AddCondition::AddAlways).
+  //
+  // Allow access to XDG_CONFIG_HOME and XDG_CONFIG_DIRS
+  nsAutoCString xdgConfigHome(PR_GetEnv("XDG_CONFIG_HOME"));
+  if (!xdgConfigHome.IsEmpty()) {  // AddPath will fail on empty strings
+    policy->AddFutureDir(rdonly, xdgConfigHome.get());
+  }
+
+  nsAutoCString xdgConfigDirs(PR_GetEnv("XDG_CONFIG_DIRS"));
+  for (const auto& path : xdgConfigDirs.Split(':')) {
+    if (!path.IsEmpty()) {  // AddPath will fail on empty strings
+      policy->AddFutureDir(rdonly, PromiseFlatCString(path).get());
+    }
+  }
+
+  // Allow fonts subdir in XDG_DATA_HOME
+  nsAutoCString xdgDataHome(PR_GetEnv("XDG_DATA_HOME"));
+  if (!xdgDataHome.IsEmpty()) {
+    nsAutoCString fontPath(xdgDataHome);
+    fontPath.Append("/fonts");
+    policy->AddFutureDir(rdonly, PromiseFlatCString(fontPath).get());
+  }
+
+  // Any font subdirs in XDG_DATA_DIRS
+  nsAutoCString xdgDataDirs(PR_GetEnv("XDG_DATA_DIRS"));
+  for (const auto& path : xdgDataDirs.Split(':')) {
+    nsAutoCString fontPath(path);
+    fontPath.Append("/fonts");
+    policy->AddFutureDir(rdonly, PromiseFlatCString(fontPath).get());
+  }
+
+  // Extra configuration/cache dirs in the homedir that we want to allow read
+  // access to.
+  std::vector<const char*> extraConfDirsAllow = {
+      ".themes",
+      ".fonts",
+      ".cache/fontconfig",
+  };
+
+  // Fallback if XDG_CONFIG_HOME isn't set
+  if (xdgConfigHome.IsEmpty()) {
+    extraConfDirsAllow.emplace_back(".config");
+  }
+
+  nsCOMPtr<nsIFile> homeDir;
+  nsresult rv =
+      GetSpecialSystemDirectory(Unix_HomeDirectory, getter_AddRefs(homeDir));
+  if (NS_SUCCEEDED(rv)) {
+    nsCOMPtr<nsIFile> confDir;
+
+    for (const auto& dir : extraConfDirsAllow) {
+      rv = homeDir->Clone(getter_AddRefs(confDir));
+      if (NS_SUCCEEDED(rv)) {
+        rv = confDir->AppendRelativeNativePath(nsDependentCString(dir));
+        if (NS_SUCCEEDED(rv)) {
+          nsAutoCString tmpPath;
+          rv = confDir->GetNativePath(tmpPath);
+          if (NS_SUCCEEDED(rv)) {
+            policy->AddDir(rdonly, tmpPath.get());
+          }
+        }
+      }
+    }
+
+    // ~/.config/mozilla/ needs to be manually blocked, because the previous
+    // loop will allow for ~/.config/ access.
+    {
+      // If $XDG_CONFIG_HOME is set, we need to account for it.
+      // FIXME: Bug 1722272: Maybe this should just be handled with
+      // GetSpecialSystemDirectory(Unix_XDG_ConfigHome) ?
+      nsCOMPtr<nsIFile> confDirOrXDGConfigHomeDir;
+      if (!xdgConfigHome.IsEmpty()) {
+        rv = NS_NewNativeLocalFile(xdgConfigHome, true,
+                                   getter_AddRefs(confDirOrXDGConfigHomeDir));
+        // confDirOrXDGConfigHomeDir = nsIFile($XDG_CONFIG_HOME)
+      } else {
+        rv = homeDir->Clone(getter_AddRefs(confDirOrXDGConfigHomeDir));
+        if (NS_SUCCEEDED(rv)) {
+          // since we will use that later, we dont need to care about trailing
+          // slash
+          rv = confDirOrXDGConfigHomeDir->AppendNative(".config"_ns);
+          // confDirOrXDGConfigHomeDir = nsIFile($HOME/.config/)
+        }
+      }
+
+      if (NS_SUCCEEDED(rv)) {
+        rv = confDirOrXDGConfigHomeDir->AppendNative("mozilla"_ns);
+        if (NS_SUCCEEDED(rv)) {
+          nsAutoCString tmpPath;
+          rv = confDirOrXDGConfigHomeDir->GetNativePath(tmpPath);
+          if (NS_SUCCEEDED(rv)) {
+            policy->AddFutureDir(deny, tmpPath.get());
+          }
+        }
+      }
+    }
+
+    // ~/.local/share (for themes)
+    rv = homeDir->Clone(getter_AddRefs(confDir));
+    if (NS_SUCCEEDED(rv)) {
+      rv = confDir->AppendNative(".local"_ns);
+      if (NS_SUCCEEDED(rv)) {
+        rv = confDir->AppendNative("share"_ns);
+      }
+      if (NS_SUCCEEDED(rv)) {
+        nsAutoCString tmpPath;
+        rv = confDir->GetNativePath(tmpPath);
+        if (NS_SUCCEEDED(rv)) {
+          policy->AddDir(rdonly, tmpPath.get());
+        }
+      }
+    }
+
+    // ~/.fonts.conf (Fontconfig)
+    rv = homeDir->Clone(getter_AddRefs(confDir));
+    if (NS_SUCCEEDED(rv)) {
+      rv = confDir->AppendNative(".fonts.conf"_ns);
+      if (NS_SUCCEEDED(rv)) {
+        nsAutoCString tmpPath;
+        rv = confDir->GetNativePath(tmpPath);
+        if (NS_SUCCEEDED(rv)) {
+          policy->AddPath(rdonly, tmpPath.get());
+        }
+      }
+    }
+
+    // .pangorc
+    rv = homeDir->Clone(getter_AddRefs(confDir));
+    if (NS_SUCCEEDED(rv)) {
+      rv = confDir->AppendNative(".pangorc"_ns);
+      if (NS_SUCCEEDED(rv)) {
+        nsAutoCString tmpPath;
+        rv = confDir->GetNativePath(tmpPath);
+        if (NS_SUCCEEDED(rv)) {
+          policy->AddPath(rdonly, tmpPath.get());
+        }
+      }
+    }
+  }
+
+  // Firefox binary dir.
+  // Note that unlike the previous cases, we use NS_GetSpecialDirectory
+  // instead of GetSpecialSystemDirectory. The former requires a working XPCOM
+  // system, which may not be the case for some tests. For querying for the
+  // location of XPCOM things, we can use it anyway.
+  nsCOMPtr<nsIFile> ffDir;
+  rv = NS_GetSpecialDirectory(NS_GRE_DIR, getter_AddRefs(ffDir));
+  if (NS_SUCCEEDED(rv)) {
+    nsAutoCString tmpPath;
+    rv = ffDir->GetNativePath(tmpPath);
+    if (NS_SUCCEEDED(rv)) {
+      policy->AddDir(rdonly, tmpPath.get());
+    }
+  }
+
+  if (!mozilla::IsPackagedBuild()) {
+    // If this is not a packaged build the resources are likely symlinks to
+    // outside the binary dir. Therefore in non-release builds we allow reads
+    // from the whole repository. MOZ_DEVELOPER_REPO_DIR is set by mach run.
+    const char* developer_repo_dir = PR_GetEnv("MOZ_DEVELOPER_REPO_DIR");
+    if (developer_repo_dir) {
+      policy->AddDir(rdonly, developer_repo_dir);
+    }
+  }
+
+#ifdef DEBUG
+  char* bloatLog = PR_GetEnv("XPCOM_MEM_BLOAT_LOG");
+  // XPCOM_MEM_BLOAT_LOG has the format
+  // /tmp/tmpd0YzFZ.mozrunner/runtests_leaks.log
+  // but stores into /tmp/tmpd0YzFZ.mozrunner/runtests_leaks_tab_pid3411.log
+  // So cut the .log part and whitelist the prefix.
+  if (bloatLog != nullptr) {
+    size_t bloatLen = strlen(bloatLog);
+    if (bloatLen >= 4) {
+      nsAutoCString bloatStr(bloatLog);
+      bloatStr.Truncate(bloatLen - 4);
+      policy->AddPrefix(rdwrcr, bloatStr.get());
+    }
+  }
+#endif
+
+  if (!headless) {
+    AddX11Dependencies(policy);
+  }
+
+  // Bug 1732580: when packaged as a strictly confined snap, may need
+  // read-access to configuration files under $SNAP/.
+  const char* snap = PR_GetEnv("SNAP");
+  if (snap) {
+    // When running as a snap, the directory pointed to by $SNAP is guaranteed
+    // to exist before the app is launched, but unit tests need to create it
+    // dynamically, hence the use of AddFutureDir().
+    policy->AddDir(rdonly, snap);
+  }
+
+  // Read any extra paths that will get write permissions,
+  // configured by the user or distro
+  AddDynamicPathList(policy, "security.sandbox.content.write_path_whitelist",
+                     rdwr);
+
+  // Whitelisted for reading by the user/distro
+  AddDynamicPathList(policy, "security.sandbox.content.read_path_whitelist",
+                     rdonly);
+
+#if defined(MOZ_CONTENT_TEMP_DIR)
+  // Add write permissions on the content process specific temporary dir.
+  nsCOMPtr<nsIFile> tmpDir;
+  rv = NS_GetSpecialDirectory(NS_APP_CONTENT_PROCESS_TEMP_DIR,
+                              getter_AddRefs(tmpDir));
+  if (NS_SUCCEEDED(rv)) {
+    nsAutoCString tmpPath;
+    rv = tmpDir->GetNativePath(tmpPath);
+    if (NS_SUCCEEDED(rv)) {
+      policy->AddDir(rdwrcr, tmpPath.get());
+    }
+  }
+#endif
+
+  // userContent.css and the extensions dir sit in the profile, which is
+  // normally blocked.
+  nsCOMPtr<nsIFile> profileDir;
+  rv = NS_GetSpecialDirectory(NS_APP_USER_PROFILE_50_DIR,
+                              getter_AddRefs(profileDir));
+  if (NS_SUCCEEDED(rv)) {
+    nsCOMPtr<nsIFile> workDir;
+    rv = profileDir->Clone(getter_AddRefs(workDir));
+    if (NS_SUCCEEDED(rv)) {
+      rv = workDir->AppendNative("chrome"_ns);
+      if (NS_SUCCEEDED(rv)) {
+        nsAutoCString tmpPath;
+        rv = workDir->GetNativePath(tmpPath);
+        if (NS_SUCCEEDED(rv)) {
+          policy->AddDir(rdonly, tmpPath.get());
+        }
+      }
+    }
+    rv = profileDir->Clone(getter_AddRefs(workDir));
+    if (NS_SUCCEEDED(rv)) {
+      rv = workDir->AppendNative("extensions"_ns);
+      if (NS_SUCCEEDED(rv)) {
+        nsAutoCString tmpPath;
+        rv = workDir->GetNativePath(tmpPath);
+        if (NS_SUCCEEDED(rv)) {
+          bool exists;
+          rv = workDir->Exists(&exists);
+          if (NS_SUCCEEDED(rv)) {
+            if (!exists) {
+              policy->AddPrefix(rdonly, tmpPath.get());
+              policy->AddPath(rdonly, tmpPath.get());
+            } else {
+              policy->AddDir(rdonly, tmpPath.get());
+            }
+          }
+        }
+      }
+    }
+  }
+
+  const int level = GetEffectiveContentSandboxLevel();
+  bool allowPulse = false;
+  bool allowAlsa = false;
+  if (level < 4) {
+#ifdef MOZ_PULSEAUDIO
+    allowPulse = true;
+#endif
+#ifdef MOZ_ALSA
+    allowAlsa = true;
+#endif
+  }
+
+  if (allowAlsa) {
+    // Bug 1309098: ALSA support
+    policy->AddDir(rdwr, "/dev/snd");
+  }
+
+  if (allowPulse) {
+    policy->AddDir(rdwrcr, "/dev/shm");
+  }
+
+#ifdef MOZ_WIDGET_GTK
+  if (const auto userDir = g_get_user_runtime_dir()) {
+    // Bug 1321134: DConf's single bit of shared memory
+    // The leaf filename is "user" by default, but is configurable.
+    nsPrintfCString shmPath("%s/dconf/", userDir);
+    policy->AddPrefix(rdwrcr, shmPath.get());
+    policy->AddAncestors(shmPath.get());
+    if (allowPulse) {
+      // PulseAudio, if it can't get server info from X11, will break
+      // unless it can open this directory (or create it, but in our use
+      // case we know it already exists).  See bug 1335329.
+      nsPrintfCString pulsePath("%s/pulse", userDir);
+      policy->AddPath(rdonly, pulsePath.get());
+    }
+  }
+#endif  // MOZ_WIDGET_GTK
+
+  if (allowPulse) {
+    // PulseAudio also needs access to read the $XAUTHORITY file (see
+    // bug 1384986 comment #1), but that's already allowed for hybrid
+    // GPU drivers (see above).
+    policy->AddPath(rdonly, "/var/lib/dbus/machine-id");
+  }
+
+  // Bug 1434711 - AMDGPU-PRO crashes if it can't read it's marketing ids
+  // and various other things
+  if (!headless && HasAtiDrivers()) {
+    policy->AddDir(rdonly, "/opt/amdgpu/share");
+    policy->AddPath(rdonly, "/sys/module/amdgpu");
+  }
+
+  mCommonContentPolicy.reset(policy);
+}
+
+UniquePtr<SandboxBroker::Policy> SandboxBrokerPolicyFactory::GetContentPolicy(
+    int aPid, bool aFileProcess) {
+  // Policy entries that vary per-process (because they depend on the
+  // pid or content subtype) are added here.
+
+  MOZ_ASSERT(NS_IsMainThread());
+
+  const int level = GetEffectiveContentSandboxLevel();
+  // The file broker is used at level 2 and up.
+  if (level <= 1) {
+    // Level 1 has been removed.
+    MOZ_ASSERT(level == 0);
+    return nullptr;
+  }
+
+  std::call_once(mContentInited, [this] { InitContentPolicy(); });
+  MOZ_ASSERT(mCommonContentPolicy);
+  UniquePtr<SandboxBroker::Policy> policy(
+      new SandboxBroker::Policy(*mCommonContentPolicy));
+
+  // No read blocking at level 2 and below.
+  // file:// processes also get global read permissions
+  if (level <= 2 || aFileProcess) {
+    policy->AddDir(rdonly, "/");
+    // Any other read-only rules will be removed as redundant by
+    // Policy::FixRecursivePermissions, so there's no need to
+    // early-return here.
+  }
+
+  // Access to /dev/shm is restricted to a per-process prefix to
+  // prevent interfering with other processes or with services outside
+  // the browser (e.g., PulseAudio).
+  AddSharedMemoryPaths(policy.get(), aPid);
+
+  // Bug 1198550: the profiler's replacement for dl_iterate_phdr
+  policy->AddPath(rdonly, nsPrintfCString("/proc/%d/maps", aPid).get());
+
+  // Bug 1736040: CPU use telemetry
+  policy->AddPath(rdonly, nsPrintfCString("/proc/%d/stat", aPid).get());
+
+  // Bug 1198552: memory reporting.
+  AddMemoryReporting(policy.get(), aPid);
+
+  // Bug 1384804, notably comment 15
+  // Used by libnuma, included by x265/ffmpeg, who falls back
+  // to get_mempolicy if this fails
+  policy->AddPath(rdonly, nsPrintfCString("/proc/%d/status", aPid).get());
+
+  // Finalize the policy.
+  policy->FixRecursivePermissions();
+  return policy;
+}
+
+/* static */ UniquePtr<SandboxBroker::Policy>
+SandboxBrokerPolicyFactory::GetRDDPolicy(int aPid) {
+  auto policy = MakeUnique<SandboxBroker::Policy>();
+
+  AddSharedMemoryPaths(policy.get(), aPid);
+
+  policy->AddPath(rdonly, "/dev/urandom");
+  // FIXME (bug 1662321): we should fix nsSystemInfo so that every
+  // child process doesn't need to re-read these files to get the info
+  // the parent process already has.
+  policy->AddPath(rdonly, "/proc/cpuinfo");
+  policy->AddPath(rdonly,
+                  "/sys/devices/system/cpu/cpu0/cpufreq/cpuinfo_max_freq");
+  policy->AddPath(rdonly, "/sys/devices/system/cpu/cpu0/cache/index2/size");
+  policy->AddPath(rdonly, "/sys/devices/system/cpu/cpu0/cache/index3/size");
+  policy->AddDir(rdonly, "/sys/devices/cpu");
+  policy->AddDir(rdonly, "/sys/devices/system/cpu");
+  policy->AddDir(rdonly, "/sys/devices/system/node");
+  policy->AddDir(rdonly, "/lib");
+  policy->AddDir(rdonly, "/lib64");
+  policy->AddDir(rdonly, "/usr/lib");
+  policy->AddDir(rdonly, "/usr/lib32");
+  policy->AddDir(rdonly, "/usr/lib64");
+  policy->AddDir(rdonly, "/run/opengl-driver/lib");
+  policy->AddDir(rdonly, "/nix/store");
+
+  // Bug 1647957: memory reporting.
+  AddMemoryReporting(policy.get(), aPid);
+
+  // Firefox binary dir.
+  // Note that unlike the previous cases, we use NS_GetSpecialDirectory
+  // instead of GetSpecialSystemDirectory. The former requires a working XPCOM
+  // system, which may not be the case for some tests. For querying for the
+  // location of XPCOM things, we can use it anyway.
+  nsCOMPtr<nsIFile> ffDir;
+  nsresult rv = NS_GetSpecialDirectory(NS_GRE_DIR, getter_AddRefs(ffDir));
+  if (NS_SUCCEEDED(rv)) {
+    nsAutoCString tmpPath;
+    rv = ffDir->GetNativePath(tmpPath);
+    if (NS_SUCCEEDED(rv)) {
+      policy->AddDir(rdonly, tmpPath.get());
+    }
+  }
+
+  if (!mozilla::IsPackagedBuild()) {
+    // If this is not a packaged build the resources are likely symlinks to
+    // outside the binary dir. Therefore in non-release builds we allow reads
+    // from the whole repository. MOZ_DEVELOPER_REPO_DIR is set by mach run.
+    const char* developer_repo_dir = PR_GetEnv("MOZ_DEVELOPER_REPO_DIR");
+    if (developer_repo_dir) {
+      policy->AddDir(rdonly, developer_repo_dir);
+    }
+  }
+
+  // VA-API needs GPU access and GL context creation (but not display
+  // server access, as of bug 1769499).
+  AddGLDependencies(policy.get());
+
+  // FFmpeg and GPU drivers may need general-case library loading
+  AddLdconfigPaths(policy.get());
+  AddLdLibraryEnvPaths(policy.get());
+
+  if (policy->IsEmpty()) {
+    policy = nullptr;
+  }
+  return policy;
+}
+
+/* static */ UniquePtr<SandboxBroker::Policy>
+SandboxBrokerPolicyFactory::GetSocketProcessPolicy(int aPid) {
+  auto policy = MakeUnique<SandboxBroker::Policy>();
+
+  policy->AddPath(rdonly, "/dev/urandom");
+  policy->AddPath(rdonly, "/dev/random");
+  policy->AddPath(rdonly, "/proc/sys/crypto/fips_enabled");
+  policy->AddPath(rdonly, "/proc/cpuinfo");
+  policy->AddPath(rdonly, "/proc/meminfo");
+  policy->AddDir(rdonly, "/sys/devices/cpu");
+  policy->AddDir(rdonly, "/sys/devices/system/cpu");
+  policy->AddDir(rdonly, "/lib");
+  policy->AddDir(rdonly, "/lib64");
+  policy->AddDir(rdonly, "/usr/lib");
+  policy->AddDir(rdonly, "/usr/lib32");
+  policy->AddDir(rdonly, "/usr/lib64");
+  policy->AddDir(rdonly, "/usr/share");
+  policy->AddDir(rdonly, "/usr/local/share");
+  policy->AddDir(rdonly, "/etc");
+
+  // glibc will try to stat64("/") while populating nsswitch database
+  // https://sourceware.org/git/?p=glibc.git;a=blob;f=nss/nss_database.c;h=cf0306adc47f12d9bc761ab1b013629f4482b7e6;hb=9826b03b747b841f5fc6de2054bf1ef3f5c4bdf3#l396
+  // denying will make getaddrinfo() return ENONAME
+  policy->AddDir(access, "/");
+
+  AddLdconfigPaths(policy.get());
+
+  // Socket process sandbox needs to allow shmem in order to support
+  // profiling.  See Bug 1626385.
+  AddSharedMemoryPaths(policy.get(), aPid);
+
+  // Bug 1647957: memory reporting.
+  AddMemoryReporting(policy.get(), aPid);
+
+  // Firefox binary dir.
+  // Note that unlike the previous cases, we use NS_GetSpecialDirectory
+  // instead of GetSpecialSystemDirectory. The former requires a working XPCOM
+  // system, which may not be the case for some tests. For querying for the
+  // location of XPCOM things, we can use it anyway.
+  nsCOMPtr<nsIFile> ffDir;
+  nsresult rv = NS_GetSpecialDirectory(NS_GRE_DIR, getter_AddRefs(ffDir));
+  if (NS_SUCCEEDED(rv)) {
+    nsAutoCString tmpPath;
+    rv = ffDir->GetNativePath(tmpPath);
+    if (NS_SUCCEEDED(rv)) {
+      policy->AddDir(rdonly, tmpPath.get());
+    }
+  }
+
+  if (policy->IsEmpty()) {
+    policy = nullptr;
+  }
+  return policy;
+}
+
+/* static */ UniquePtr<SandboxBroker::Policy>
+SandboxBrokerPolicyFactory::GetUtilityProcessPolicy(int aPid) {
+  auto policy = MakeUnique<SandboxBroker::Policy>();
+
+  policy->AddPath(rdonly, "/dev/urandom");
+  policy->AddPath(rdonly, "/proc/cpuinfo");
+  policy->AddPath(rdonly, "/proc/meminfo");
+  policy->AddPath(rdonly, nsPrintfCString("/proc/%d/exe", aPid).get());
+  policy->AddDir(rdonly, "/sys/devices/cpu");
+  policy->AddDir(rdonly, "/sys/devices/system/cpu");
+  policy->AddDir(rdonly, "/lib");
+  policy->AddDir(rdonly, "/lib64");
+  policy->AddDir(rdonly, "/usr/lib");
+  policy->AddDir(rdonly, "/usr/lib32");
+  policy->AddDir(rdonly, "/usr/lib64");
+  policy->AddDir(rdonly, "/usr/share");
+  policy->AddDir(rdonly, "/usr/local/share");
+  policy->AddDir(rdonly, "/etc");
+
+  // glibc will try to stat64("/") while populating nsswitch database
+  // https://sourceware.org/git/?p=glibc.git;a=blob;f=nss/nss_database.c;h=cf0306adc47f12d9bc761ab1b013629f4482b7e6;hb=9826b03b747b841f5fc6de2054bf1ef3f5c4bdf3#l396
+  // denying will make getaddrinfo() return ENONAME
+  policy->AddDir(access, "/");
+
+  AddLdconfigPaths(policy.get());
+  AddLdLibraryEnvPaths(policy.get());
+
+  // Utility process sandbox needs to allow shmem in order to support
+  // profiling.  See Bug 1626385.
+  AddSharedMemoryPaths(policy.get(), aPid);
+
+  // Bug 1647957: memory reporting.
+  AddMemoryReporting(policy.get(), aPid);
+
+  // Firefox binary dir.
+  // Note that unlike the previous cases, we use NS_GetSpecialDirectory
+  // instead of GetSpecialSystemDirectory. The former requires a working XPCOM
+  // system, which may not be the case for some tests. For querying for the
+  // location of XPCOM things, we can use it anyway.
+  nsCOMPtr<nsIFile> ffDir;
+  nsresult rv = NS_GetSpecialDirectory(NS_GRE_DIR, getter_AddRefs(ffDir));
+  if (NS_SUCCEEDED(rv)) {
+    nsAutoCString tmpPath;
+    rv = ffDir->GetNativePath(tmpPath);
+    if (NS_SUCCEEDED(rv)) {
+      policy->AddDir(rdonly, tmpPath.get());
+    }
+  }
+
+  if (policy->IsEmpty()) {
+    policy = nullptr;
+  }
+  return policy;
+}
+
+}  // namespace mozilla