Linux sandbox: restrict prctl in the baseline.

sandbox/linux/seccomp-bpf-helpers/baseline_policy.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 "sandbox/linux/seccomp-bpf-helpers/baseline_policy.h"
 
 #include <errno.h>
 #include <sys/mman.h>
 #include <sys/socket.h>
 #include <sys/syscall.h>
@@ skipping 18 matching lines @@
 
 bool IsBaselinePolicyAllowed(int sysno) {
   return SyscallSets::IsAllowedAddressSpaceAccess(sysno) ||
          SyscallSets::IsAllowedBasicScheduler(sysno) ||
          SyscallSets::IsAllowedEpoll(sysno) ||
          SyscallSets::IsAllowedFileSystemAccessViaFd(sysno) ||
          SyscallSets::IsAllowedFutex(sysno) ||
          SyscallSets::IsAllowedGeneralIo(sysno) ||
          SyscallSets::IsAllowedGetOrModifySocket(sysno) ||
          SyscallSets::IsAllowedGettime(sysno) ||
-         SyscallSets::IsAllowedPrctl(sysno) ||
          SyscallSets::IsAllowedProcessStartOrDeath(sysno) ||
          SyscallSets::IsAllowedSignalHandling(sysno) ||
          SyscallSets::IsGetSimpleId(sysno) ||
          SyscallSets::IsKernelInternalApi(sysno) ||
 #if defined(__arm__)
          SyscallSets::IsArmPrivate(sysno) ||
 #endif
          SyscallSets::IsAllowedOperationOnFd(sysno);
 }
 
@@ skipping 14 matching lines @@
          SyscallSets::IsInotify(sysno) ||
          SyscallSets::IsKernelModule(sysno) ||
          SyscallSets::IsKeyManagement(sysno) ||
          SyscallSets::IsKill(sysno) ||
          SyscallSets::IsMessageQueue(sysno) ||
          SyscallSets::IsMisc(sysno) ||
 #if defined(__x86_64__)
          SyscallSets::IsNetworkSocketInformation(sysno) ||
 #endif
          SyscallSets::IsNuma(sysno) ||
+         SyscallSets::IsPrctl(sysno) ||
          SyscallSets::IsProcessGroupOrSession(sysno) ||
 #if defined(__i386__)
          SyscallSets::IsSocketCall(sysno) ||
 #endif
 #if defined(__arm__)
          SyscallSets::IsArmPciConfig(sysno) ||
 #endif
          SyscallSets::IsTimer(sysno);
 }
 
@@ skipping 54 matching lines @@
 #endif
 
 #if defined(__i386__) || defined(__arm__)
   if (sysno == __NR_mmap2)
     return RestrictMmapFlags(sandbox);
 #endif
 
   if (sysno == __NR_mprotect)
     return RestrictMprotectFlags(sandbox);
 
+  if (sysno == __NR_prctl)
+    return sandbox::RestrictPrctl(sandbox);
+
 #if defined(__x86_64__) || defined(__arm__)
   if (sysno == __NR_socketpair) {
     // Only allow AF_UNIX, PF_UNIX. Crash if anything else is seen.
     COMPILE_ASSERT(AF_UNIX == PF_UNIX, af_unix_pf_unix_different);
     return sandbox->Cond(0, ErrorCode::TP_32BIT, ErrorCode::OP_EQUAL, AF_UNIX,
                          ErrorCode(ErrorCode::ERR_ALLOWED),
                          sandbox->Trap(CrashSIGSYS_Handler, NULL));
   }
 #endif
 
@@ skipping 51 matching lines @@
 ErrorCode BaselinePolicy::EvaluateSyscall(SandboxBPF* sandbox,
                                           int sysno) const {
   // Make sure that this policy is used in the creating process.
   if (1 == sysno) {
     DCHECK_EQ(syscall(__NR_getpid), current_pid_);
   }
   return EvaluateSyscallImpl(fs_denied_errno_, current_pid_, sandbox, sysno);
 }
 
 }  // namespace sandbox.