1 // Copyright 2019 Google LLC 2 // 3 // Licensed under the Apache License, Version 2.0 (the "License"); 4 // you may not use this file except in compliance with the License. 5 // You may obtain a copy of the License at 6 // 7 // https://www.apache.org/licenses/LICENSE-2.0 8 // 9 // Unless required by applicable law or agreed to in writing, software 10 // distributed under the License is distributed on an "AS IS" BASIS, 11 // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 12 // See the License for the specific language governing permissions and 13 // limitations under the License. 14 15 #include "sandboxed_api/sandbox2/forkingclient.h" 16 17 #include <unistd.h> 18 19 #include <cstdlib> 20 #include <memory> 21 22 #include "absl/log/check.h" 23 #include "absl/log/log.h" 24 #include "sandboxed_api/sandbox2/forkserver.h" 25 #include "sandboxed_api/sandbox2/sanitizer.h" 26 #include "sandboxed_api/util/raw_logging.h" 27 28 namespace sandbox2 { 29 WaitAndFork()30pid_t ForkingClient::WaitAndFork() { 31 // We don't instantiate the Fork-Server until the first Fork() call takes 32 // place (in order to conserve resources, and avoid calling Fork-Server 33 // initialization routines). 34 if (!fork_server_worker_) { 35 sanitizer::WaitForSanitizer(); 36 // Perform that check once only, because it's quite CPU-expensive. 37 int n = sanitizer::GetNumberOfThreads(getpid()); 38 CHECK_NE(n, -1) << "sanitizer::GetNumberOfThreads failed"; 39 CHECK_EQ(n, 1) << "Too many threads (" << n 40 << ") during sandbox2::Client::WaitAndFork()"; 41 fork_server_worker_ = std::make_unique<ForkServer>(comms_); 42 } 43 pid_t pid = fork_server_worker_->ServeRequest(); 44 if (pid == -1 && fork_server_worker_->IsTerminated()) { 45 VLOG(1) << "ForkServer Comms closed. Exiting"; 46 exit(0); 47 } 48 return pid; 49 } 50 51 } // namespace sandbox2 52