com_android_internal_os_Zygote.cpp revision a87723515627401f142aec1fd98b8863b726a1a3
1/* 2 * Copyright (C) 2008 The Android Open Source Project 3 * 4 * Licensed under the Apache License, Version 2.0 (the "License"); 5 * you may not use this file except in compliance with the License. 6 * You may obtain a copy of the License at 7 * 8 * http://www.apache.org/licenses/LICENSE-2.0 9 * 10 * Unless required by applicable law or agreed to in writing, software 11 * distributed under the License is distributed on an "AS IS" BASIS, 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 13 * See the License for the specific language governing permissions and 14 * limitations under the License. 15 */ 16 17#define LOG_TAG "Zygote" 18 19// sys/mount.h has to come before linux/fs.h due to redefinition of MS_RDONLY, MS_BIND, etc 20#include <sys/mount.h> 21#include <linux/fs.h> 22 23#include <list> 24#include <sstream> 25#include <string> 26 27#include <fcntl.h> 28#include <grp.h> 29#include <inttypes.h> 30#include <mntent.h> 31#include <paths.h> 32#include <signal.h> 33#include <stdlib.h> 34#include <sys/capability.h> 35#include <sys/personality.h> 36#include <sys/prctl.h> 37#include <sys/resource.h> 38#include <sys/stat.h> 39#include <sys/types.h> 40#include <sys/utsname.h> 41#include <sys/wait.h> 42#include <unistd.h> 43 44#include <cutils/fs.h> 45#include <cutils/multiuser.h> 46#include <cutils/sched_policy.h> 47#include <private/android_filesystem_config.h> 48#include <utils/String8.h> 49#include <selinux/android.h> 50#include <processgroup/processgroup.h> 51 52#include "core_jni_helpers.h" 53#include "JNIHelp.h" 54#include "ScopedLocalRef.h" 55#include "ScopedPrimitiveArray.h" 56#include "ScopedUtfChars.h" 57 58#include "nativebridge/native_bridge.h" 59 60namespace { 61 62using android::String8; 63 64static pid_t gSystemServerPid = 0; 65 66static const char kZygoteClassName[] = "com/android/internal/os/Zygote"; 67static jclass gZygoteClass; 68static jmethodID gCallPostForkChildHooks; 69 70// Must match values in com.android.internal.os.Zygote. 71enum MountExternalKind { 72 MOUNT_EXTERNAL_NONE = 0, 73 MOUNT_EXTERNAL_DEFAULT = 1, 74 MOUNT_EXTERNAL_READ = 2, 75 MOUNT_EXTERNAL_WRITE = 3, 76}; 77 78static void RuntimeAbort(JNIEnv* env, int line, const char* msg) { 79 std::ostringstream oss; 80 oss << __FILE__ << ":" << line << ": " << msg; 81 env->FatalError(oss.str().c_str()); 82} 83 84// This signal handler is for zygote mode, since the zygote must reap its children 85static void SigChldHandler(int /*signal_number*/) { 86 pid_t pid; 87 int status; 88 89 // It's necessary to save and restore the errno during this function. 90 // Since errno is stored per thread, changing it here modifies the errno 91 // on the thread on which this signal handler executes. If a signal occurs 92 // between a call and an errno check, it's possible to get the errno set 93 // here. 94 // See b/23572286 for extra information. 95 int saved_errno = errno; 96 97 while ((pid = waitpid(-1, &status, WNOHANG)) > 0) { 98 // Log process-death status that we care about. In general it is 99 // not safe to call LOG(...) from a signal handler because of 100 // possible reentrancy. However, we know a priori that the 101 // current implementation of LOG() is safe to call from a SIGCHLD 102 // handler in the zygote process. If the LOG() implementation 103 // changes its locking strategy or its use of syscalls within the 104 // lazy-init critical section, its use here may become unsafe. 105 if (WIFEXITED(status)) { 106 if (WEXITSTATUS(status)) { 107 ALOGI("Process %d exited cleanly (%d)", pid, WEXITSTATUS(status)); 108 } 109 } else if (WIFSIGNALED(status)) { 110 if (WTERMSIG(status) != SIGKILL) { 111 ALOGI("Process %d exited due to signal (%d)", pid, WTERMSIG(status)); 112 } 113 if (WCOREDUMP(status)) { 114 ALOGI("Process %d dumped core.", pid); 115 } 116 } 117 118 // If the just-crashed process is the system_server, bring down zygote 119 // so that it is restarted by init and system server will be restarted 120 // from there. 121 if (pid == gSystemServerPid) { 122 ALOGE("Exit zygote because system server (%d) has terminated", pid); 123 kill(getpid(), SIGKILL); 124 } 125 } 126 127 // Note that we shouldn't consider ECHILD an error because 128 // the secondary zygote might have no children left to wait for. 129 if (pid < 0 && errno != ECHILD) { 130 ALOGW("Zygote SIGCHLD error in waitpid: %s", strerror(errno)); 131 } 132 133 errno = saved_errno; 134} 135 136// Configures the SIGCHLD handler for the zygote process. This is configured 137// very late, because earlier in the runtime we may fork() and exec() 138// other processes, and we want to waitpid() for those rather than 139// have them be harvested immediately. 140// 141// This ends up being called repeatedly before each fork(), but there's 142// no real harm in that. 143static void SetSigChldHandler() { 144 struct sigaction sa; 145 memset(&sa, 0, sizeof(sa)); 146 sa.sa_handler = SigChldHandler; 147 148 int err = sigaction(SIGCHLD, &sa, NULL); 149 if (err < 0) { 150 ALOGW("Error setting SIGCHLD handler: %s", strerror(errno)); 151 } 152} 153 154// Sets the SIGCHLD handler back to default behavior in zygote children. 155static void UnsetSigChldHandler() { 156 struct sigaction sa; 157 memset(&sa, 0, sizeof(sa)); 158 sa.sa_handler = SIG_DFL; 159 160 int err = sigaction(SIGCHLD, &sa, NULL); 161 if (err < 0) { 162 ALOGW("Error unsetting SIGCHLD handler: %s", strerror(errno)); 163 } 164} 165 166// Calls POSIX setgroups() using the int[] object as an argument. 167// A NULL argument is tolerated. 168static void SetGids(JNIEnv* env, jintArray javaGids) { 169 if (javaGids == NULL) { 170 return; 171 } 172 173 ScopedIntArrayRO gids(env, javaGids); 174 if (gids.get() == NULL) { 175 RuntimeAbort(env, __LINE__, "Getting gids int array failed"); 176 } 177 int rc = setgroups(gids.size(), reinterpret_cast<const gid_t*>(&gids[0])); 178 if (rc == -1) { 179 RuntimeAbort(env, __LINE__, "setgroups failed"); 180 } 181} 182 183// Sets the resource limits via setrlimit(2) for the values in the 184// two-dimensional array of integers that's passed in. The second dimension 185// contains a tuple of length 3: (resource, rlim_cur, rlim_max). NULL is 186// treated as an empty array. 187static void SetRLimits(JNIEnv* env, jobjectArray javaRlimits) { 188 if (javaRlimits == NULL) { 189 return; 190 } 191 192 rlimit rlim; 193 memset(&rlim, 0, sizeof(rlim)); 194 195 for (int i = 0; i < env->GetArrayLength(javaRlimits); ++i) { 196 ScopedLocalRef<jobject> javaRlimitObject(env, env->GetObjectArrayElement(javaRlimits, i)); 197 ScopedIntArrayRO javaRlimit(env, reinterpret_cast<jintArray>(javaRlimitObject.get())); 198 if (javaRlimit.size() != 3) { 199 RuntimeAbort(env, __LINE__, "rlimits array must have a second dimension of size 3"); 200 } 201 202 rlim.rlim_cur = javaRlimit[1]; 203 rlim.rlim_max = javaRlimit[2]; 204 205 int rc = setrlimit(javaRlimit[0], &rlim); 206 if (rc == -1) { 207 ALOGE("setrlimit(%d, {%ld, %ld}) failed", javaRlimit[0], rlim.rlim_cur, 208 rlim.rlim_max); 209 RuntimeAbort(env, __LINE__, "setrlimit failed"); 210 } 211 } 212} 213 214// The debug malloc library needs to know whether it's the zygote or a child. 215extern "C" int gMallocLeakZygoteChild; 216 217static void EnableKeepCapabilities(JNIEnv* env) { 218 int rc = prctl(PR_SET_KEEPCAPS, 1, 0, 0, 0); 219 if (rc == -1) { 220 RuntimeAbort(env, __LINE__, "prctl(PR_SET_KEEPCAPS) failed"); 221 } 222} 223 224static void DropCapabilitiesBoundingSet(JNIEnv* env) { 225 for (int i = 0; prctl(PR_CAPBSET_READ, i, 0, 0, 0) >= 0; i++) { 226 int rc = prctl(PR_CAPBSET_DROP, i, 0, 0, 0); 227 if (rc == -1) { 228 if (errno == EINVAL) { 229 ALOGE("prctl(PR_CAPBSET_DROP) failed with EINVAL. Please verify " 230 "your kernel is compiled with file capabilities support"); 231 } else { 232 RuntimeAbort(env, __LINE__, "prctl(PR_CAPBSET_DROP) failed"); 233 } 234 } 235 } 236} 237 238static void SetCapabilities(JNIEnv* env, int64_t permitted, int64_t effective) { 239 __user_cap_header_struct capheader; 240 memset(&capheader, 0, sizeof(capheader)); 241 capheader.version = _LINUX_CAPABILITY_VERSION_3; 242 capheader.pid = 0; 243 244 __user_cap_data_struct capdata[2]; 245 memset(&capdata, 0, sizeof(capdata)); 246 capdata[0].effective = effective; 247 capdata[1].effective = effective >> 32; 248 capdata[0].permitted = permitted; 249 capdata[1].permitted = permitted >> 32; 250 251 if (capset(&capheader, &capdata[0]) == -1) { 252 ALOGE("capset(%" PRId64 ", %" PRId64 ") failed", permitted, effective); 253 RuntimeAbort(env, __LINE__, "capset failed"); 254 } 255} 256 257static void SetSchedulerPolicy(JNIEnv* env) { 258 errno = -set_sched_policy(0, SP_DEFAULT); 259 if (errno != 0) { 260 ALOGE("set_sched_policy(0, SP_DEFAULT) failed"); 261 RuntimeAbort(env, __LINE__, "set_sched_policy(0, SP_DEFAULT) failed"); 262 } 263} 264 265static int UnmountTree(const char* path) { 266 size_t path_len = strlen(path); 267 268 FILE* fp = setmntent("/proc/mounts", "r"); 269 if (fp == NULL) { 270 ALOGE("Error opening /proc/mounts: %s", strerror(errno)); 271 return -errno; 272 } 273 274 // Some volumes can be stacked on each other, so force unmount in 275 // reverse order to give us the best chance of success. 276 std::list<std::string> toUnmount; 277 mntent* mentry; 278 while ((mentry = getmntent(fp)) != NULL) { 279 if (strncmp(mentry->mnt_dir, path, path_len) == 0) { 280 toUnmount.push_front(std::string(mentry->mnt_dir)); 281 } 282 } 283 endmntent(fp); 284 285 for (auto path : toUnmount) { 286 if (umount2(path.c_str(), MNT_DETACH)) { 287 ALOGW("Failed to unmount %s: %s", path.c_str(), strerror(errno)); 288 } 289 } 290 return 0; 291} 292 293// Create a private mount namespace and bind mount appropriate emulated 294// storage for the given user. 295static bool MountEmulatedStorage(uid_t uid, jint mount_mode, 296 bool force_mount_namespace) { 297 // See storage config details at http://source.android.com/tech/storage/ 298 299 // Create a second private mount namespace for our process 300 if (unshare(CLONE_NEWNS) == -1) { 301 ALOGW("Failed to unshare(): %s", strerror(errno)); 302 return false; 303 } 304 305 // Unmount storage provided by root namespace and mount requested view 306 UnmountTree("/storage"); 307 308 String8 storageSource; 309 if (mount_mode == MOUNT_EXTERNAL_DEFAULT) { 310 storageSource = "/mnt/runtime/default"; 311 } else if (mount_mode == MOUNT_EXTERNAL_READ) { 312 storageSource = "/mnt/runtime/read"; 313 } else if (mount_mode == MOUNT_EXTERNAL_WRITE) { 314 storageSource = "/mnt/runtime/write"; 315 } else { 316 // Sane default of no storage visible 317 return true; 318 } 319 if (TEMP_FAILURE_RETRY(mount(storageSource.string(), "/storage", 320 NULL, MS_BIND | MS_REC | MS_SLAVE, NULL)) == -1) { 321 ALOGW("Failed to mount %s to /storage: %s", storageSource.string(), strerror(errno)); 322 return false; 323 } 324 325 // Mount user-specific symlink helper into place 326 userid_t user_id = multiuser_get_user_id(uid); 327 const String8 userSource(String8::format("/mnt/user/%d", user_id)); 328 if (fs_prepare_dir(userSource.string(), 0751, 0, 0) == -1) { 329 return false; 330 } 331 if (TEMP_FAILURE_RETRY(mount(userSource.string(), "/storage/self", 332 NULL, MS_BIND, NULL)) == -1) { 333 ALOGW("Failed to mount %s to /storage/self: %s", userSource.string(), strerror(errno)); 334 return false; 335 } 336 337 return true; 338} 339 340static bool NeedsNoRandomizeWorkaround() { 341#if !defined(__arm__) 342 return false; 343#else 344 int major; 345 int minor; 346 struct utsname uts; 347 if (uname(&uts) == -1) { 348 return false; 349 } 350 351 if (sscanf(uts.release, "%d.%d", &major, &minor) != 2) { 352 return false; 353 } 354 355 // Kernels before 3.4.* need the workaround. 356 return (major < 3) || ((major == 3) && (minor < 4)); 357#endif 358} 359 360// Utility to close down the Zygote socket file descriptors while 361// the child is still running as root with Zygote's privileges. Each 362// descriptor (if any) is closed via dup2(), replacing it with a valid 363// (open) descriptor to /dev/null. 364 365static void DetachDescriptors(JNIEnv* env, jintArray fdsToClose) { 366 if (!fdsToClose) { 367 return; 368 } 369 jsize count = env->GetArrayLength(fdsToClose); 370 ScopedIntArrayRO ar(env, fdsToClose); 371 if (ar.get() == NULL) { 372 RuntimeAbort(env, __LINE__, "Bad fd array"); 373 } 374 jsize i; 375 int devnull; 376 for (i = 0; i < count; i++) { 377 devnull = open("/dev/null", O_RDWR); 378 if (devnull < 0) { 379 ALOGE("Failed to open /dev/null: %s", strerror(errno)); 380 RuntimeAbort(env, __LINE__, "Failed to open /dev/null"); 381 continue; 382 } 383 ALOGV("Switching descriptor %d to /dev/null: %s", ar[i], strerror(errno)); 384 if (dup2(devnull, ar[i]) < 0) { 385 ALOGE("Failed dup2() on descriptor %d: %s", ar[i], strerror(errno)); 386 RuntimeAbort(env, __LINE__, "Failed dup2()"); 387 } 388 close(devnull); 389 } 390} 391 392void SetThreadName(const char* thread_name) { 393 bool hasAt = false; 394 bool hasDot = false; 395 const char* s = thread_name; 396 while (*s) { 397 if (*s == '.') { 398 hasDot = true; 399 } else if (*s == '@') { 400 hasAt = true; 401 } 402 s++; 403 } 404 const int len = s - thread_name; 405 if (len < 15 || hasAt || !hasDot) { 406 s = thread_name; 407 } else { 408 s = thread_name + len - 15; 409 } 410 // pthread_setname_np fails rather than truncating long strings. 411 char buf[16]; // MAX_TASK_COMM_LEN=16 is hard-coded into bionic 412 strlcpy(buf, s, sizeof(buf)-1); 413 errno = pthread_setname_np(pthread_self(), buf); 414 if (errno != 0) { 415 ALOGW("Unable to set the name of current thread to '%s': %s", buf, strerror(errno)); 416 } 417} 418 419#ifdef ENABLE_SCHED_BOOST 420static void SetForkLoad(bool boost) { 421 // set scheduler knob to boost forked processes 422 pid_t currentPid = getpid(); 423 // fits at most "/proc/XXXXXXX/sched_init_task_load\0" 424 char schedPath[35]; 425 snprintf(schedPath, sizeof(schedPath), "/proc/%u/sched_init_task_load", currentPid); 426 int schedBoostFile = open(schedPath, O_WRONLY); 427 if (schedBoostFile < 0) { 428 ALOGW("Unable to set zygote scheduler boost"); 429 return; 430 } 431 if (boost) { 432 write(schedBoostFile, "100\0", 4); 433 } else { 434 write(schedBoostFile, "0\0", 2); 435 } 436 close(schedBoostFile); 437} 438#endif 439 440// Utility routine to fork zygote and specialize the child process. 441static pid_t ForkAndSpecializeCommon(JNIEnv* env, uid_t uid, gid_t gid, jintArray javaGids, 442 jint debug_flags, jobjectArray javaRlimits, 443 jlong permittedCapabilities, jlong effectiveCapabilities, 444 jint mount_external, 445 jstring java_se_info, jstring java_se_name, 446 bool is_system_server, jintArray fdsToClose, 447 jstring instructionSet, jstring dataDir) { 448 SetSigChldHandler(); 449 450#ifdef ENABLE_SCHED_BOOST 451 SetForkLoad(true); 452#endif 453 454 pid_t pid = fork(); 455 456 if (pid == 0) { 457 // The child process. 458 gMallocLeakZygoteChild = 1; 459 460 // Clean up any descriptors which must be closed immediately 461 DetachDescriptors(env, fdsToClose); 462 463 // Keep capabilities across UID change, unless we're staying root. 464 if (uid != 0) { 465 EnableKeepCapabilities(env); 466 } 467 468 DropCapabilitiesBoundingSet(env); 469 470 bool use_native_bridge = !is_system_server && (instructionSet != NULL) 471 && android::NativeBridgeAvailable(); 472 if (use_native_bridge) { 473 ScopedUtfChars isa_string(env, instructionSet); 474 use_native_bridge = android::NeedsNativeBridge(isa_string.c_str()); 475 } 476 if (use_native_bridge && dataDir == NULL) { 477 // dataDir should never be null if we need to use a native bridge. 478 // In general, dataDir will never be null for normal applications. It can only happen in 479 // special cases (for isolated processes which are not associated with any app). These are 480 // launched by the framework and should not be emulated anyway. 481 use_native_bridge = false; 482 ALOGW("Native bridge will not be used because dataDir == NULL."); 483 } 484 485 if (!MountEmulatedStorage(uid, mount_external, use_native_bridge)) { 486 ALOGW("Failed to mount emulated storage: %s", strerror(errno)); 487 if (errno == ENOTCONN || errno == EROFS) { 488 // When device is actively encrypting, we get ENOTCONN here 489 // since FUSE was mounted before the framework restarted. 490 // When encrypted device is booting, we get EROFS since 491 // FUSE hasn't been created yet by init. 492 // In either case, continue without external storage. 493 } else { 494 RuntimeAbort(env, __LINE__, "Cannot continue without emulated storage"); 495 } 496 } 497 498 if (!is_system_server) { 499 int rc = createProcessGroup(uid, getpid()); 500 if (rc != 0) { 501 if (rc == -EROFS) { 502 ALOGW("createProcessGroup failed, kernel missing CONFIG_CGROUP_CPUACCT?"); 503 } else { 504 ALOGE("createProcessGroup(%d, %d) failed: %s", uid, pid, strerror(-rc)); 505 } 506 } 507 } 508 509 SetGids(env, javaGids); 510 511 SetRLimits(env, javaRlimits); 512 513 if (use_native_bridge) { 514 ScopedUtfChars isa_string(env, instructionSet); 515 ScopedUtfChars data_dir(env, dataDir); 516 android::PreInitializeNativeBridge(data_dir.c_str(), isa_string.c_str()); 517 } 518 519 int rc = setresgid(gid, gid, gid); 520 if (rc == -1) { 521 ALOGE("setresgid(%d) failed: %s", gid, strerror(errno)); 522 RuntimeAbort(env, __LINE__, "setresgid failed"); 523 } 524 525 rc = setresuid(uid, uid, uid); 526 if (rc == -1) { 527 ALOGE("setresuid(%d) failed: %s", uid, strerror(errno)); 528 RuntimeAbort(env, __LINE__, "setresuid failed"); 529 } 530 531 if (NeedsNoRandomizeWorkaround()) { 532 // Work around ARM kernel ASLR lossage (http://b/5817320). 533 int old_personality = personality(0xffffffff); 534 int new_personality = personality(old_personality | ADDR_NO_RANDOMIZE); 535 if (new_personality == -1) { 536 ALOGW("personality(%d) failed: %s", new_personality, strerror(errno)); 537 } 538 } 539 540 SetCapabilities(env, permittedCapabilities, effectiveCapabilities); 541 542 SetSchedulerPolicy(env); 543 544 const char* se_info_c_str = NULL; 545 ScopedUtfChars* se_info = NULL; 546 if (java_se_info != NULL) { 547 se_info = new ScopedUtfChars(env, java_se_info); 548 se_info_c_str = se_info->c_str(); 549 if (se_info_c_str == NULL) { 550 RuntimeAbort(env, __LINE__, "se_info_c_str == NULL"); 551 } 552 } 553 const char* se_name_c_str = NULL; 554 ScopedUtfChars* se_name = NULL; 555 if (java_se_name != NULL) { 556 se_name = new ScopedUtfChars(env, java_se_name); 557 se_name_c_str = se_name->c_str(); 558 if (se_name_c_str == NULL) { 559 RuntimeAbort(env, __LINE__, "se_name_c_str == NULL"); 560 } 561 } 562 rc = selinux_android_setcontext(uid, is_system_server, se_info_c_str, se_name_c_str); 563 if (rc == -1) { 564 ALOGE("selinux_android_setcontext(%d, %d, \"%s\", \"%s\") failed", uid, 565 is_system_server, se_info_c_str, se_name_c_str); 566 RuntimeAbort(env, __LINE__, "selinux_android_setcontext failed"); 567 } 568 569 // Make it easier to debug audit logs by setting the main thread's name to the 570 // nice name rather than "app_process". 571 if (se_info_c_str == NULL && is_system_server) { 572 se_name_c_str = "system_server"; 573 } 574 if (se_info_c_str != NULL) { 575 SetThreadName(se_name_c_str); 576 } 577 578 delete se_info; 579 delete se_name; 580 581 UnsetSigChldHandler(); 582 583 env->CallStaticVoidMethod(gZygoteClass, gCallPostForkChildHooks, debug_flags, 584 is_system_server, instructionSet); 585 if (env->ExceptionCheck()) { 586 RuntimeAbort(env, __LINE__, "Error calling post fork hooks."); 587 } 588 } else if (pid > 0) { 589 // the parent process 590 591#ifdef ENABLE_SCHED_BOOST 592 // unset scheduler knob 593 SetForkLoad(false); 594#endif 595 596 } 597 return pid; 598} 599} // anonymous namespace 600 601namespace android { 602 603static jint com_android_internal_os_Zygote_nativeForkAndSpecialize( 604 JNIEnv* env, jclass, jint uid, jint gid, jintArray gids, 605 jint debug_flags, jobjectArray rlimits, 606 jint mount_external, jstring se_info, jstring se_name, 607 jintArray fdsToClose, jstring instructionSet, jstring appDataDir) { 608 jlong capabilities = 0; 609 if (uid == AID_BLUETOOTH) { 610 // Grant CAP_WAKE_ALARM and CAP_BLOCK_SUSPEND to the Bluetooth process. 611 capabilities |= (1LL << CAP_WAKE_ALARM); 612 capabilities |= (1LL << CAP_BLOCK_SUSPEND); 613 614 // Add the Bluetooth process to the system group. 615 jsize length = env->GetArrayLength(reinterpret_cast<jarray>(gids)); 616 jintArray gids_with_system = env->NewIntArray(length + 1); 617 if (!gids_with_system) { 618 RuntimeAbort(env, __LINE__, "could not allocate java array for gids"); 619 } 620 621 jint *gids_elements = env->GetIntArrayElements(gids, NULL); 622 jint *gids_with_system_elements = env->GetIntArrayElements(gids_with_system, NULL); 623 624 if (!gids_elements || !gids_with_system_elements) { 625 RuntimeAbort(env, __LINE__, "could not allocate arrays for gids"); 626 } 627 628 gids_with_system_elements[0] = AID_SYSTEM; 629 memcpy(&gids_with_system_elements[1], &gids_elements[0], length * sizeof(jint)); 630 631 env->ReleaseIntArrayElements(gids, gids_elements, JNI_ABORT); 632 env->ReleaseIntArrayElements(gids_with_system, gids_with_system_elements, 0); 633 gids = gids_with_system; 634 } 635 636 return ForkAndSpecializeCommon(env, uid, gid, gids, debug_flags, 637 rlimits, capabilities, capabilities, mount_external, se_info, 638 se_name, false, fdsToClose, instructionSet, appDataDir); 639} 640 641static jint com_android_internal_os_Zygote_nativeForkSystemServer( 642 JNIEnv* env, jclass, uid_t uid, gid_t gid, jintArray gids, 643 jint debug_flags, jobjectArray rlimits, jlong permittedCapabilities, 644 jlong effectiveCapabilities) { 645 pid_t pid = ForkAndSpecializeCommon(env, uid, gid, gids, 646 debug_flags, rlimits, 647 permittedCapabilities, effectiveCapabilities, 648 MOUNT_EXTERNAL_DEFAULT, NULL, NULL, true, NULL, 649 NULL, NULL); 650 if (pid > 0) { 651 // The zygote process checks whether the child process has died or not. 652 ALOGI("System server process %d has been created", pid); 653 gSystemServerPid = pid; 654 // There is a slight window that the system server process has crashed 655 // but it went unnoticed because we haven't published its pid yet. So 656 // we recheck here just to make sure that all is well. 657 int status; 658 if (waitpid(pid, &status, WNOHANG) == pid) { 659 ALOGE("System server process %d has died. Restarting Zygote!", pid); 660 RuntimeAbort(env, __LINE__, "System server process has died. Restarting Zygote!"); 661 } 662 } 663 return pid; 664} 665 666static const JNINativeMethod gMethods[] = { 667 { "nativeForkAndSpecialize", 668 "(II[II[[IILjava/lang/String;Ljava/lang/String;[ILjava/lang/String;Ljava/lang/String;)I", 669 (void *) com_android_internal_os_Zygote_nativeForkAndSpecialize }, 670 { "nativeForkSystemServer", "(II[II[[IJJ)I", 671 (void *) com_android_internal_os_Zygote_nativeForkSystemServer } 672}; 673 674int register_com_android_internal_os_Zygote(JNIEnv* env) { 675 gZygoteClass = MakeGlobalRefOrDie(env, FindClassOrDie(env, kZygoteClassName)); 676 gCallPostForkChildHooks = GetStaticMethodIDOrDie(env, gZygoteClass, "callPostForkChildHooks", 677 "(IZLjava/lang/String;)V"); 678 679 return RegisterMethodsOrDie(env, "com/android/internal/os/Zygote", gMethods, NELEM(gMethods)); 680} 681} // namespace android 682 683