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diff --git a/security/sandbox/linux/broker/SandboxBrokerPolicyFactory.cpp b/security/sandbox/linux/broker/SandboxBrokerPolicyFactory.cpp
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+/* -*- 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 "mozilla/ClearOnShutdown.h"
+#include "mozilla/Preferences.h"
+#include "nsPrintfCString.h"
+#include "nsString.h"
+#include "nsThreadUtils.h"
+#include "nsXULAppAPI.h"
+#include "SpecialSystemDirectory.h"
+
+#ifdef ANDROID
+#include "cutils/properties.h"
+#endif
+
+namespace mozilla {
+
+/* static */ bool
+SandboxBrokerPolicyFactory::IsSystemSupported() {
+#ifdef ANDROID
+ char hardware[PROPERTY_VALUE_MAX];
+ int length = property_get("ro.hardware", hardware, nullptr);
+ // "goldfish" -> emulator. Other devices can be added when we're
+ // reasonably sure they work. Eventually this won't be needed....
+ if (length > 0 && strcmp(hardware, "goldfish") == 0) {
+ return true;
+ }
+
+ // When broker is running in permissive mode, we enable it
+ // automatically regardless of the device.
+ if (SandboxInfo::Get().Test(SandboxInfo::kPermissive)) {
+ return true;
+ }
+#endif
+ return false;
+}
+
+#if defined(MOZ_CONTENT_SANDBOX)
+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;
+#if defined(MOZ_WIDGET_GONK)
+static const int wrlog = wronly | SandboxBroker::MAY_CREATE;
+#endif
+}
+#endif
+
+SandboxBrokerPolicyFactory::SandboxBrokerPolicyFactory()
+{
+ // Policy entries that are the same in every process go here, and
+ // are cached over the lifetime of the factory.
+#if defined(MOZ_CONTENT_SANDBOX) && defined(MOZ_WIDGET_GONK)
+ SandboxBroker::Policy* policy = new SandboxBroker::Policy;
+
+ // Devices that need write access:
+ policy->AddPath(rdwr, "/dev/genlock"); // bug 980924
+ policy->AddPath(rdwr, "/dev/ashmem"); // bug 980947
+ policy->AddTree(wronly, "/dev/log"); // bug 1199857
+ // Graphics devices are a significant source of attack surface, but
+ // there's not much we can do about it without proxying (which is
+ // very difficult and a perforamnce hit).
+ policy->AddPrefix(rdwr, "/dev", "kgsl"); // bug 995072
+ policy->AddPath(rdwr, "/dev/qemu_pipe"); // but 1198410: goldfish gralloc.
+
+ // Bug 1198475: mochitest logs. (This is actually passed in via URL
+ // query param to the mochitest page, and is configurable, so this
+ // isn't enough in general, but hopefully it's good enough for B2G.)
+ // Conditional on tests being run, using the same check seen in
+ // DirectoryProvider.js to set ProfD.
+ if (access("/data/local/tests/profile", R_OK) == 0) {
+ policy->AddPath(wrlog, "/data/local/tests/log/mochitest.log");
+ }
+
+ // Read-only items below this line.
+
+ policy->AddPath(rdonly, "/dev/urandom"); // bug 964500, bug 995069
+ policy->AddPath(rdonly, "/dev/ion"); // bug 980937
+ policy->AddPath(rdonly, "/proc/cpuinfo"); // bug 995067
+ policy->AddPath(rdonly, "/proc/meminfo"); // bug 1025333
+ policy->AddPath(rdonly, "/sys/devices/system/cpu/present"); // bug 1025329
+ policy->AddPath(rdonly, "/sys/devices/system/soc/soc0/id"); // bug 1025339
+ policy->AddPath(rdonly, "/etc/media_profiles.xml"); // bug 1198419
+ policy->AddPath(rdonly, "/etc/media_codecs.xml"); // bug 1198460
+ policy->AddTree(rdonly, "/system/fonts"); // bug 1026063
+
+ // Bug 1199051 (crossplatformly, this is NS_GRE_DIR).
+ policy->AddTree(rdonly, "/system/b2g");
+
+ // Bug 1026356: dynamic library loading from assorted frameworks we
+ // don't control (media codecs, maybe others).
+ //
+ // Bug 1198515: Also, the profiler calls breakpad code to get info
+ // on all loaded ELF objects, which opens those files.
+ policy->AddTree(rdonly, "/system/lib");
+ policy->AddTree(rdonly, "/vendor/lib");
+ policy->AddPath(rdonly, "/system/bin/linker"); // (profiler only)
+
+ // Bug 1199866: EGL/WebGL.
+ policy->AddPath(rdonly, "/system/lib/egl");
+ policy->AddPath(rdonly, "/vendor/lib/egl");
+
+ // Bug 1198401: timezones. Yes, we need both of these; see bug.
+ policy->AddTree(rdonly, "/system/usr/share/zoneinfo");
+ policy->AddTree(rdonly, "/system//usr/share/zoneinfo");
+
+ policy->AddPath(rdonly, "/data/local/tmp/profiler.options",
+ SandboxBroker::Policy::AddAlways); // bug 1029337
+
+ mCommonContentPolicy.reset(policy);
+#elif defined(MOZ_CONTENT_SANDBOX)
+ SandboxBroker::Policy* policy = new SandboxBroker::Policy;
+ policy->AddDir(rdonly, "/");
+ policy->AddDir(rdwrcr, "/dev/shm");
+ // Add write permissions on the temporary directory. This can come
+ // from various environment variables (TMPDIR,TMP,TEMP,...) so
+ // make sure to use the full logic.
+ nsCOMPtr<nsIFile> tmpDir;
+ nsresult rv = GetSpecialSystemDirectory(OS_TemporaryDirectory,
+ getter_AddRefs(tmpDir));
+ if (NS_SUCCEEDED(rv)) {
+ nsAutoCString tmpPath;
+ rv = tmpDir->GetNativePath(tmpPath);
+ if (NS_SUCCEEDED(rv)) {
+ policy->AddDir(rdwrcr, tmpPath.get());
+ }
+ }
+ // If the above fails at any point, fall back to a very good guess.
+ if (NS_FAILED(rv)) {
+ policy->AddDir(rdwrcr, "/tmp");
+ }
+
+ // Bug 1308851: NVIDIA proprietary driver when using WebGL
+ policy->AddPrefix(rdwr, "/dev", "nvidia");
+
+ // Bug 1312678: radeonsi/Intel with DRI when using WebGL
+ policy->AddDir(rdwr, "/dev/dri");
+
+ mCommonContentPolicy.reset(policy);
+#endif
+}
+
+#ifdef MOZ_CONTENT_SANDBOX
+UniquePtr<SandboxBroker::Policy>
+SandboxBrokerPolicyFactory::GetContentPolicy(int aPid)
+{
+ // Policy entries that vary per-process (currently the only reason
+ // that can happen is because they contain the pid) are added here.
+
+ MOZ_ASSERT(NS_IsMainThread());
+ // File broker usage is controlled through a pref.
+ if (Preferences::GetInt("security.sandbox.content.level") <= 1) {
+ return nullptr;
+ }
+
+ MOZ_ASSERT(mCommonContentPolicy);
+#if defined(MOZ_WIDGET_GONK)
+ // Allow overriding "unsupported"ness with a pref, for testing.
+ if (!IsSystemSupported()) {
+ return nullptr;
+ }
+ UniquePtr<SandboxBroker::Policy>
+ policy(new SandboxBroker::Policy(*mCommonContentPolicy));
+
+ // Bug 1029337: where the profiler writes the data.
+ nsPrintfCString profilerLogPath("/data/local/tmp/profile_%d_%d.txt",
+ GeckoProcessType_Content, aPid);
+ policy->AddPath(wrlog, profilerLogPath.get());
+
+ // Bug 1198550: the profiler's replacement for dl_iterate_phdr
+ policy->AddPath(rdonly, nsPrintfCString("/proc/%d/maps", aPid).get());
+
+ // Bug 1198552: memory reporting.
+ policy->AddPath(rdonly, nsPrintfCString("/proc/%d/statm", aPid).get());
+ policy->AddPath(rdonly, nsPrintfCString("/proc/%d/smaps", aPid).get());
+
+ return policy;
+#else
+ UniquePtr<SandboxBroker::Policy>
+ policy(new SandboxBroker::Policy(*mCommonContentPolicy));
+ // Return the common policy.
+ return policy;
+#endif
+}
+
+#endif // MOZ_CONTENT_SANDBOX
+} // namespace mozilla