Linux sandbox: always restrict clone() in baseline policy.

content/common/sandbox_linux/android/sandbox_bpf_base_policy_android.cc

 // Copyright 2014 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "content/common/sandbox_linux/android/sandbox_bpf_base_policy_android.h"
 
 #include <sys/types.h>
 
 #include "sandbox/linux/seccomp-bpf/sandbox_bpf.h"
 
 namespace content {
 
 SandboxBPFBasePolicyAndroid::SandboxBPFBasePolicyAndroid()
     : SandboxBPFBasePolicy() {}
 
 SandboxBPFBasePolicyAndroid::~SandboxBPFBasePolicyAndroid() {}
 
 sandbox::ErrorCode SandboxBPFBasePolicyAndroid::EvaluateSyscall(
     sandbox::SandboxBPF* sandbox,
     int sysno) const {
   bool override_and_allow = false;
 
   switch (sysno) {
+    // TODO(rsesek): restrict clone parameters.
+    case __NR_clone:
     case __NR_epoll_pwait:
     case __NR_flock:
     case __NR_getpriority:
     case __NR_ioctl:
     case __NR_mremap:
     // File system access cannot be restricted with seccomp-bpf on Android,
     // since the JVM classloader and other Framework features require file
     // access. It may be possible to restrict the filesystem with SELinux.
     // Currently we rely on the app/service UID isolation to create a
     // filesystem "sandbox".
@@ skipping 15 matching lines @@
       break;
   }
 
   if (override_and_allow)
     return sandbox::ErrorCode(sandbox::ErrorCode::ERR_ALLOWED);
 
   return SandboxBPFBasePolicy::EvaluateSyscall(sandbox, sysno);
 }
 
 }  // namespace content