Linux sandbox: Restrict sched_* syscalls on the GPU and ppapi processes.

content/common/sandbox_linux/bpf_gpu_policy_linux.cc

 // Copyright (c) 2013 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/bpf_gpu_policy_linux.h"
 
 #include <dlfcn.h>
 #include <errno.h>
 #include <fcntl.h>
 #include <sys/socket.h>
 #include <sys/stat.h>
 #include <sys/types.h>
 #include <unistd.h>
 
 #include <string>
 #include <vector>
 
 #include "base/bind.h"
 #include "base/command_line.h"
 #include "base/compiler_specific.h"
 #include "base/logging.h"
 #include "base/memory/scoped_ptr.h"
 #include "build/build_config.h"
 #include "content/common/sandbox_linux/sandbox_bpf_base_policy_linux.h"
 #include "content/common/sandbox_linux/sandbox_seccomp_bpf_linux.h"
 #include "content/common/set_process_title.h"
 #include "content/public/common/content_switches.h"
+#include "sandbox/linux/seccomp-bpf-helpers/syscall_parameters_restrictions.h"
 #include "sandbox/linux/seccomp-bpf-helpers/syscall_sets.h"
 #include "sandbox/linux/seccomp-bpf/trap.h"
 #include "sandbox/linux/services/broker_process.h"
 #include "sandbox/linux/services/linux_syscalls.h"
 
 using sandbox::BrokerProcess;
 using sandbox::SyscallSets;
 using sandbox::arch_seccomp_data;
 using sandbox::bpf_dsl::Allow;
 using sandbox::bpf_dsl::ResultExpr;
@@ skipping 141 matching lines @@
 #if defined(__i386__) || defined(__x86_64__) || defined(__mips__)
     // The Nvidia driver uses flags not in the baseline policy
     // (MAP_LOCKED | MAP_EXECUTABLE | MAP_32BIT)
     case __NR_mmap:
 #endif
     // We also hit this on the linux_chromeos bot but don't yet know what
     // weird flags were involved.
     case __NR_mprotect:
     // TODO(jln): restrict prctl.
     case __NR_prctl:
-    case __NR_sched_getaffinity:
-    case __NR_sched_setaffinity:
-    case __NR_setpriority:
       return Allow();
     case __NR_access:
     case __NR_open:
     case __NR_openat:
       DCHECK(broker_process_);
       return Trap(GpuSIGSYS_Handler, broker_process_);
+    case __NR_setpriority:
+      return sandbox::RestrictGetSetpriority(GetPolicyPid());
+    case __NR_sched_getaffinity:
+    case __NR_sched_setaffinity:
+      return sandbox::RestrictSchedTarget(GetPolicyPid(), sysno);
     default:
       if (SyscallSets::IsEventFd(sysno))
         return Allow();
 
       // Default on the baseline policy.
       return SandboxBPFBasePolicy::EvaluateSyscall(sysno);
   }
 }
 
 bool GpuProcessPolicy::PreSandboxHook() {
@@ skipping 59 matching lines @@
   broker_process_ = new BrokerProcess(GetFSDeniedErrno(),
                                       read_whitelist,
                                       write_whitelist);
   // The initialization callback will perform generic initialization and then
   // call broker_sandboxer_callback.
   CHECK(broker_process_->Init(base::Bind(&UpdateProcessTypeAndEnableSandbox,
                                          broker_sandboxer_allocator)));
 }
 
 }  // namespace content