1 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
2 // Use of this source code is governed by a BSD-style license that can be
3 // found in the LICENSE file.
5 #include "content/zygote/zygote_main.h"
12 #include <sys/socket.h>
13 #include <sys/types.h>
18 #include "base/basictypes.h"
19 #include "base/bind.h"
20 #include "base/command_line.h"
21 #include "base/compiler_specific.h"
22 #include "base/memory/scoped_vector.h"
23 #include "base/native_library.h"
24 #include "base/pickle.h"
25 #include "base/posix/eintr_wrapper.h"
26 #include "base/posix/unix_domain_socket_linux.h"
27 #include "base/rand_util.h"
28 #include "base/strings/safe_sprintf.h"
29 #include "base/strings/string_number_conversions.h"
30 #include "base/sys_info.h"
31 #include "build/build_config.h"
32 #include "content/common/child_process_sandbox_support_impl_linux.h"
33 #include "content/common/font_config_ipc_linux.h"
34 #include "content/common/sandbox_linux/sandbox_linux.h"
35 #include "content/common/zygote_commands_linux.h"
36 #include "content/public/common/content_switches.h"
37 #include "content/public/common/main_function_params.h"
38 #include "content/public/common/sandbox_linux.h"
39 #include "content/public/common/zygote_fork_delegate_linux.h"
40 #include "content/zygote/zygote_linux.h"
41 #include "crypto/nss_util.h"
42 #include "sandbox/linux/services/init_process_reaper.h"
43 #include "sandbox/linux/services/libc_urandom_override.h"
44 #include "sandbox/linux/suid/client/setuid_sandbox_client.h"
45 #include "third_party/icu/source/i18n/unicode/timezone.h"
46 #include "third_party/skia/include/ports/SkFontConfigInterface.h"
49 #include <sys/prctl.h>
52 #if defined(USE_OPENSSL)
53 #include <openssl/rand.h>
56 #if defined(ENABLE_PLUGINS)
57 #include "content/common/pepper_plugin_list.h"
58 #include "content/public/common/pepper_plugin_info.h"
61 #if defined(ENABLE_WEBRTC)
62 #include "third_party/libjingle/overrides/init_webrtc.h"
65 #if defined(ADDRESS_SANITIZER)
66 #include <sanitizer/asan_interface.h>
73 void DoChrootSignalHandler(int) {
74 const int old_errno
= errno
;
75 const char kFirstMessage
[] = "Chroot signal handler called.\n";
76 ignore_result(write(STDERR_FILENO
, kFirstMessage
, sizeof(kFirstMessage
) - 1));
78 const int chroot_ret
= chroot("/");
80 char kSecondMessage
[100];
81 const ssize_t printed
=
82 base::strings::SafeSPrintf(kSecondMessage
,
83 "chroot() returned %d. Errno is %d.\n",
86 if (printed
> 0 && printed
< static_cast<ssize_t
>(sizeof(kSecondMessage
))) {
87 ignore_result(write(STDERR_FILENO
, kSecondMessage
, printed
));
92 // This is a quick hack to allow testing sandbox crash reports in production
94 // This installs a signal handler for SIGUSR2 that performs a chroot().
95 // In most of our BPF policies, it is a "watched" system call which will
96 // trigger a SIGSYS signal whose handler will crash.
97 // This has been added during the investigation of https://crbug.com/415842.
98 void InstallSandboxCrashTestHandler() {
99 struct sigaction act
= {};
100 act
.sa_handler
= DoChrootSignalHandler
;
101 CHECK_EQ(0, sigemptyset(&act
.sa_mask
));
104 PCHECK(0 == sigaction(SIGUSR2
, &act
, NULL
));
107 void CloseFds(const std::vector
<int>& fds
) {
108 for (const auto& it
: fds
) {
109 PCHECK(0 == IGNORE_EINTR(close(it
)));
115 // See http://code.google.com/p/chromium/wiki/LinuxZygote
117 static void ProxyLocaltimeCallToBrowser(time_t input
, struct tm
* output
,
119 size_t timezone_out_len
) {
121 request
.WriteInt(LinuxSandbox::METHOD_LOCALTIME
);
123 std::string(reinterpret_cast<char*>(&input
), sizeof(input
)));
125 uint8_t reply_buf
[512];
126 const ssize_t r
= UnixDomainSocket::SendRecvMsg(
127 GetSandboxFD(), reply_buf
, sizeof(reply_buf
), NULL
,
130 memset(output
, 0, sizeof(struct tm
));
134 Pickle
reply(reinterpret_cast<char*>(reply_buf
), r
);
135 PickleIterator
iter(reply
);
136 std::string result
, timezone
;
137 if (!iter
.ReadString(&result
) ||
138 !iter
.ReadString(&timezone
) ||
139 result
.size() != sizeof(struct tm
)) {
140 memset(output
, 0, sizeof(struct tm
));
144 memcpy(output
, result
.data(), sizeof(struct tm
));
145 if (timezone_out_len
) {
146 const size_t copy_len
= std::min(timezone_out_len
- 1, timezone
.size());
147 memcpy(timezone_out
, timezone
.data(), copy_len
);
148 timezone_out
[copy_len
] = 0;
149 output
->tm_zone
= timezone_out
;
151 output
->tm_zone
= NULL
;
155 static bool g_am_zygote_or_renderer
= false;
157 // Sandbox interception of libc calls.
159 // Because we are running in a sandbox certain libc calls will fail (localtime
160 // being the motivating example - it needs to read /etc/localtime). We need to
161 // intercept these calls and proxy them to the browser. However, these calls
162 // may come from us or from our libraries. In some cases we can't just change
165 // It's for these cases that we have the following setup:
167 // We define global functions for those functions which we wish to override.
168 // Since we will be first in the dynamic resolution order, the dynamic linker
169 // will point callers to our versions of these functions. However, we have the
170 // same binary for both the browser and the renderers, which means that our
171 // overrides will apply in the browser too.
173 // The global |g_am_zygote_or_renderer| is true iff we are in a zygote or
174 // renderer process. It's set in ZygoteMain and inherited by the renderers when
175 // they fork. (This means that it'll be incorrect for global constructor
176 // functions and before ZygoteMain is called - beware).
178 // Our replacement functions can check this global and either proxy
179 // the call to the browser over the sandbox IPC
180 // (http://code.google.com/p/chromium/wiki/LinuxSandboxIPC) or they can use
181 // dlsym with RTLD_NEXT to resolve the symbol, ignoring any symbols in the
186 // Our first attempt involved some assembly to patch the GOT of the current
187 // module. This worked, but was platform specific and doesn't catch the case
188 // where a library makes a call rather than current module.
190 // We also considered patching the function in place, but this would again by
191 // platform specific and the above technique seems to work well enough.
193 typedef struct tm
* (*LocaltimeFunction
)(const time_t* timep
);
194 typedef struct tm
* (*LocaltimeRFunction
)(const time_t* timep
,
197 static pthread_once_t g_libc_localtime_funcs_guard
= PTHREAD_ONCE_INIT
;
198 static LocaltimeFunction g_libc_localtime
;
199 static LocaltimeFunction g_libc_localtime64
;
200 static LocaltimeRFunction g_libc_localtime_r
;
201 static LocaltimeRFunction g_libc_localtime64_r
;
203 static void InitLibcLocaltimeFunctions() {
204 g_libc_localtime
= reinterpret_cast<LocaltimeFunction
>(
205 dlsym(RTLD_NEXT
, "localtime"));
206 g_libc_localtime64
= reinterpret_cast<LocaltimeFunction
>(
207 dlsym(RTLD_NEXT
, "localtime64"));
208 g_libc_localtime_r
= reinterpret_cast<LocaltimeRFunction
>(
209 dlsym(RTLD_NEXT
, "localtime_r"));
210 g_libc_localtime64_r
= reinterpret_cast<LocaltimeRFunction
>(
211 dlsym(RTLD_NEXT
, "localtime64_r"));
213 if (!g_libc_localtime
|| !g_libc_localtime_r
) {
214 // http://code.google.com/p/chromium/issues/detail?id=16800
216 // Nvidia's libGL.so overrides dlsym for an unknown reason and replaces
217 // it with a version which doesn't work. In this case we'll get a NULL
218 // result. There's not a lot we can do at this point, so we just bodge it!
219 LOG(ERROR
) << "Your system is broken: dlsym doesn't work! This has been "
220 "reported to be caused by Nvidia's libGL. You should expect"
221 " time related functions to misbehave. "
222 "http://code.google.com/p/chromium/issues/detail?id=16800";
225 if (!g_libc_localtime
)
226 g_libc_localtime
= gmtime
;
227 if (!g_libc_localtime64
)
228 g_libc_localtime64
= g_libc_localtime
;
229 if (!g_libc_localtime_r
)
230 g_libc_localtime_r
= gmtime_r
;
231 if (!g_libc_localtime64_r
)
232 g_libc_localtime64_r
= g_libc_localtime_r
;
235 // Define localtime_override() function with asm name "localtime", so that all
236 // references to localtime() will resolve to this function. Notice that we need
237 // to set visibility attribute to "default" to export the symbol, as it is set
238 // to "hidden" by default in chrome per build/common.gypi.
239 __attribute__ ((__visibility__("default")))
240 struct tm
* localtime_override(const time_t* timep
) __asm__ ("localtime");
242 __attribute__ ((__visibility__("default")))
243 struct tm
* localtime_override(const time_t* timep
) {
244 if (g_am_zygote_or_renderer
) {
245 static struct tm time_struct
;
246 static char timezone_string
[64];
247 ProxyLocaltimeCallToBrowser(*timep
, &time_struct
, timezone_string
,
248 sizeof(timezone_string
));
251 CHECK_EQ(0, pthread_once(&g_libc_localtime_funcs_guard
,
252 InitLibcLocaltimeFunctions
));
253 struct tm
* res
= g_libc_localtime(timep
);
254 #if defined(MEMORY_SANITIZER)
255 if (res
) __msan_unpoison(res
, sizeof(*res
));
256 if (res
->tm_zone
) __msan_unpoison_string(res
->tm_zone
);
262 // Use same trick to override localtime64(), localtime_r() and localtime64_r().
263 __attribute__ ((__visibility__("default")))
264 struct tm
* localtime64_override(const time_t* timep
) __asm__ ("localtime64");
266 __attribute__ ((__visibility__("default")))
267 struct tm
* localtime64_override(const time_t* timep
) {
268 if (g_am_zygote_or_renderer
) {
269 static struct tm time_struct
;
270 static char timezone_string
[64];
271 ProxyLocaltimeCallToBrowser(*timep
, &time_struct
, timezone_string
,
272 sizeof(timezone_string
));
275 CHECK_EQ(0, pthread_once(&g_libc_localtime_funcs_guard
,
276 InitLibcLocaltimeFunctions
));
277 struct tm
* res
= g_libc_localtime64(timep
);
278 #if defined(MEMORY_SANITIZER)
279 if (res
) __msan_unpoison(res
, sizeof(*res
));
280 if (res
->tm_zone
) __msan_unpoison_string(res
->tm_zone
);
286 __attribute__ ((__visibility__("default")))
287 struct tm
* localtime_r_override(const time_t* timep
,
288 struct tm
* result
) __asm__ ("localtime_r");
290 __attribute__ ((__visibility__("default")))
291 struct tm
* localtime_r_override(const time_t* timep
, struct tm
* result
) {
292 if (g_am_zygote_or_renderer
) {
293 ProxyLocaltimeCallToBrowser(*timep
, result
, NULL
, 0);
296 CHECK_EQ(0, pthread_once(&g_libc_localtime_funcs_guard
,
297 InitLibcLocaltimeFunctions
));
298 struct tm
* res
= g_libc_localtime_r(timep
, result
);
299 #if defined(MEMORY_SANITIZER)
300 if (res
) __msan_unpoison(res
, sizeof(*res
));
301 if (res
->tm_zone
) __msan_unpoison_string(res
->tm_zone
);
307 __attribute__ ((__visibility__("default")))
308 struct tm
* localtime64_r_override(const time_t* timep
,
309 struct tm
* result
) __asm__ ("localtime64_r");
311 __attribute__ ((__visibility__("default")))
312 struct tm
* localtime64_r_override(const time_t* timep
, struct tm
* result
) {
313 if (g_am_zygote_or_renderer
) {
314 ProxyLocaltimeCallToBrowser(*timep
, result
, NULL
, 0);
317 CHECK_EQ(0, pthread_once(&g_libc_localtime_funcs_guard
,
318 InitLibcLocaltimeFunctions
));
319 struct tm
* res
= g_libc_localtime64_r(timep
, result
);
320 #if defined(MEMORY_SANITIZER)
321 if (res
) __msan_unpoison(res
, sizeof(*res
));
322 if (res
->tm_zone
) __msan_unpoison_string(res
->tm_zone
);
328 #if defined(ENABLE_PLUGINS)
329 // Loads the (native) libraries but does not initialize them (i.e., does not
330 // call PPP_InitializeModule). This is needed by the zygote on Linux to get
331 // access to the plugins before entering the sandbox.
332 void PreloadPepperPlugins() {
333 std::vector
<PepperPluginInfo
> plugins
;
334 ComputePepperPluginList(&plugins
);
335 for (size_t i
= 0; i
< plugins
.size(); ++i
) {
336 if (!plugins
[i
].is_internal
&& plugins
[i
].is_sandboxed
) {
337 base::NativeLibraryLoadError error
;
338 base::NativeLibrary library
= base::LoadNativeLibrary(plugins
[i
].path
,
340 VLOG_IF(1, !library
) << "Unable to load plugin "
341 << plugins
[i
].path
.value() << " "
344 (void)library
; // Prevent release-mode warning.
350 // This function triggers the static and lazy construction of objects that need
351 // to be created before imposing the sandbox.
352 static void ZygotePreSandboxInit() {
355 base::SysInfo::AmountOfPhysicalMemory();
356 base::SysInfo::MaxSharedMemorySize();
357 base::SysInfo::NumberOfProcessors();
359 // ICU DateFormat class (used in base/time_format.cc) needs to get the
360 // Olson timezone ID by accessing the zoneinfo files on disk. After
361 // TimeZone::createDefault is called once here, the timezone ID is
362 // cached and there's no more need to access the file system.
363 scoped_ptr
<icu::TimeZone
> zone(icu::TimeZone::createDefault());
366 // NSS libraries are loaded before sandbox is activated. This is to allow
367 // successful initialization of NSS which tries to load extra library files.
368 crypto::LoadNSSLibraries();
369 #elif defined(USE_OPENSSL)
370 // Read a random byte in order to cause BoringSSL to open a file descriptor
373 RAND_bytes(&scratch
, 1);
375 // It's possible that another hypothetical crypto stack would not require
376 // pre-sandbox init, but more likely this is just a build configuration error.
377 #error Which SSL library are you using?
379 #if defined(ENABLE_PLUGINS)
380 // Ensure access to the Pepper plugins before the sandbox is turned on.
381 PreloadPepperPlugins();
383 #if defined(ENABLE_WEBRTC)
384 InitializeWebRtcModule();
386 SkFontConfigInterface::SetGlobal(
387 new FontConfigIPC(GetSandboxFD()))->unref();
390 static bool CreateInitProcessReaper(base::Closure
* post_fork_parent_callback
) {
391 // The current process becomes init(1), this function returns from a
392 // newly created process.
393 const bool init_created
=
394 sandbox::CreateInitProcessReaper(post_fork_parent_callback
);
396 LOG(ERROR
) << "Error creating an init process to reap zombies";
402 // Enter the setuid sandbox. This requires the current process to have been
403 // created through the setuid sandbox.
404 static bool EnterSuidSandbox(sandbox::SetuidSandboxClient
* setuid_sandbox
,
405 base::Closure
* post_fork_parent_callback
) {
406 DCHECK(setuid_sandbox
);
407 DCHECK(setuid_sandbox
->IsSuidSandboxChild());
409 // Use the SUID sandbox. This still allows the seccomp sandbox to
410 // be enabled by the process later.
412 if (!setuid_sandbox
->IsSuidSandboxUpToDate()) {
414 "You are using a wrong version of the setuid binary!\n"
416 "https://code.google.com/p/chromium/wiki/LinuxSUIDSandboxDevelopment."
420 if (!setuid_sandbox
->ChrootMe())
423 if (setuid_sandbox
->IsInNewPIDNamespace()) {
424 CHECK_EQ(1, getpid())
425 << "The SUID sandbox created a new PID namespace but Zygote "
426 "is not the init process. Please, make sure the SUID "
427 "binary is up to date.";
431 // The setuid sandbox has created a new PID namespace and we need
432 // to assume the role of init.
433 CHECK(CreateInitProcessReaper(post_fork_parent_callback
));
436 #if !defined(OS_OPENBSD)
437 // Previously, we required that the binary be non-readable. This causes the
438 // kernel to mark the process as non-dumpable at startup. The thinking was
439 // that, although we were putting the renderers into a PID namespace (with
440 // the SUID sandbox), they would nonetheless be in the /same/ PID
441 // namespace. So they could ptrace each other unless they were non-dumpable.
443 // If the binary was readable, then there would be a window between process
444 // startup and the point where we set the non-dumpable flag in which a
445 // compromised renderer could ptrace attach.
447 // However, now that we have a zygote model, only the (trusted) zygote
448 // exists at this point and we can set the non-dumpable flag which is
449 // inherited by all our renderer children.
451 // Note: a non-dumpable process can't be debugged. To debug sandbox-related
452 // issues, one can specify --allow-sandbox-debugging to let the process be
454 const base::CommandLine
& command_line
=
455 *base::CommandLine::ForCurrentProcess();
456 if (!command_line
.HasSwitch(switches::kAllowSandboxDebugging
)) {
457 prctl(PR_SET_DUMPABLE
, 0, 0, 0, 0);
458 if (prctl(PR_GET_DUMPABLE
, 0, 0, 0, 0)) {
459 LOG(ERROR
) << "Failed to set non-dumpable flag";
463 // If sandbox debugging is allowed, install a handler for sandbox-related
465 InstallSandboxCrashTestHandler();
473 #if defined(ADDRESS_SANITIZER)
474 const size_t kSanitizerMaxMessageLength
= 1 * 1024 * 1024;
476 // A helper process which collects code coverage data from the renderers over a
477 // socket and dumps it to a file. See http://crbug.com/336212 for discussion.
478 static void SanitizerCoverageHelper(int socket_fd
, int file_fd
) {
479 scoped_ptr
<char[]> buffer(new char[kSanitizerMaxMessageLength
]);
481 ssize_t received_size
= HANDLE_EINTR(
482 recv(socket_fd
, buffer
.get(), kSanitizerMaxMessageLength
, 0));
483 PCHECK(received_size
>= 0);
484 if (received_size
== 0)
485 // All clients have closed the socket. We should die.
487 PCHECK(file_fd
>= 0);
488 ssize_t written_size
= 0;
489 while (written_size
< received_size
) {
491 HANDLE_EINTR(write(file_fd
, buffer
.get() + written_size
,
492 received_size
- written_size
));
493 PCHECK(write_res
>= 0);
494 written_size
+= write_res
;
496 PCHECK(0 == HANDLE_EINTR(fsync(file_fd
)));
500 // fds[0] is the read end, fds[1] is the write end.
501 static void CreateSanitizerCoverageSocketPair(int fds
[2]) {
502 PCHECK(0 == socketpair(AF_UNIX
, SOCK_SEQPACKET
, 0, fds
));
503 PCHECK(0 == shutdown(fds
[0], SHUT_WR
));
504 PCHECK(0 == shutdown(fds
[1], SHUT_RD
));
507 static pid_t
ForkSanitizerCoverageHelper(
510 base::ScopedFD file_fd
,
511 const std::vector
<int>& extra_fds_to_close
) {
516 PCHECK(0 == IGNORE_EINTR(close(parent_fd
)));
517 CloseFds(extra_fds_to_close
);
518 SanitizerCoverageHelper(child_fd
, file_fd
.get());
522 PCHECK(0 == IGNORE_EINTR(close(child_fd
)));
527 #endif // defined(ADDRESS_SANITIZER)
529 // If |is_suid_sandbox_child|, then make sure that the setuid sandbox is
531 static void EnterLayerOneSandbox(LinuxSandbox
* linux_sandbox
,
532 bool is_suid_sandbox_child
,
533 base::Closure
* post_fork_parent_callback
) {
534 DCHECK(linux_sandbox
);
536 ZygotePreSandboxInit();
538 // Check that the pre-sandbox initialization didn't spawn threads.
539 #if !defined(THREAD_SANITIZER)
540 DCHECK(linux_sandbox
->IsSingleThreaded());
543 sandbox::SetuidSandboxClient
* setuid_sandbox
=
544 linux_sandbox
->setuid_sandbox_client();
546 if (is_suid_sandbox_child
) {
547 CHECK(EnterSuidSandbox(setuid_sandbox
, post_fork_parent_callback
))
548 << "Failed to enter setuid sandbox";
552 bool ZygoteMain(const MainFunctionParams
& params
,
553 ScopedVector
<ZygoteForkDelegate
> fork_delegates
) {
554 g_am_zygote_or_renderer
= true;
555 sandbox::InitLibcUrandomOverrides();
557 std::vector
<int> fds_to_close_post_fork
;
559 LinuxSandbox
* linux_sandbox
= LinuxSandbox::GetInstance();
561 #if defined(ADDRESS_SANITIZER)
562 const std::string sancov_file_name
=
563 "zygote." + base::Uint64ToString(base::RandUint64());
564 base::ScopedFD
sancov_file_fd(
565 __sanitizer_maybe_open_cov_file(sancov_file_name
.c_str()));
566 int sancov_socket_fds
[2] = {-1, -1};
567 CreateSanitizerCoverageSocketPair(sancov_socket_fds
);
568 linux_sandbox
->sanitizer_args()->coverage_sandboxed
= 1;
569 linux_sandbox
->sanitizer_args()->coverage_fd
= sancov_socket_fds
[1];
570 linux_sandbox
->sanitizer_args()->coverage_max_block_size
=
571 kSanitizerMaxMessageLength
;
572 // Zygote termination will block until the helper process exits, which will
573 // not happen until the write end of the socket is closed everywhere. Make
574 // sure the init process does not hold on to it.
575 fds_to_close_post_fork
.push_back(sancov_socket_fds
[0]);
576 fds_to_close_post_fork
.push_back(sancov_socket_fds
[1]);
579 // Skip pre-initializing sandbox under --no-sandbox for crbug.com/444900.
580 if (!base::CommandLine::ForCurrentProcess()->HasSwitch(
581 switches::kNoSandbox
)) {
582 // This will pre-initialize the various sandboxes that need it.
583 linux_sandbox
->PreinitializeSandbox();
586 const bool must_enable_setuid_sandbox
=
587 linux_sandbox
->setuid_sandbox_client()->IsSuidSandboxChild();
588 if (must_enable_setuid_sandbox
) {
589 linux_sandbox
->setuid_sandbox_client()->CloseDummyFile();
591 // Let the ZygoteHost know we're booting up.
592 CHECK(UnixDomainSocket::SendMsg(kZygoteSocketPairFd
,
594 sizeof(kZygoteBootMessage
),
595 std::vector
<int>()));
598 VLOG(1) << "ZygoteMain: initializing " << fork_delegates
.size()
599 << " fork delegates";
600 for (ScopedVector
<ZygoteForkDelegate
>::iterator i
= fork_delegates
.begin();
601 i
!= fork_delegates
.end();
603 (*i
)->Init(GetSandboxFD(), must_enable_setuid_sandbox
);
606 const std::vector
<int> sandbox_fds_to_close_post_fork
=
607 linux_sandbox
->GetFileDescriptorsToClose();
609 fds_to_close_post_fork
.insert(fds_to_close_post_fork
.end(),
610 sandbox_fds_to_close_post_fork
.begin(),
611 sandbox_fds_to_close_post_fork
.end());
612 base::Closure post_fork_parent_callback
=
613 base::Bind(&CloseFds
, fds_to_close_post_fork
);
615 // Turn on the first layer of the sandbox if the configuration warrants it.
616 EnterLayerOneSandbox(linux_sandbox
, must_enable_setuid_sandbox
,
617 &post_fork_parent_callback
);
619 // Extra children and file descriptors created that the Zygote must have
621 std::vector
<pid_t
> extra_children
;
622 std::vector
<int> extra_fds
;
624 #if defined(ADDRESS_SANITIZER)
625 pid_t sancov_helper_pid
= ForkSanitizerCoverageHelper(
626 sancov_socket_fds
[0], sancov_socket_fds
[1], sancov_file_fd
.Pass(),
627 sandbox_fds_to_close_post_fork
);
628 // It's important that the zygote reaps the helper before dying. Otherwise,
629 // the destruction of the PID namespace could kill the helper before it
630 // completes its I/O tasks. |sancov_helper_pid| will exit once the last
631 // renderer holding the write end of |sancov_socket_fds| closes it.
632 extra_children
.push_back(sancov_helper_pid
);
633 // Sanitizer code in the renderers will inherit the write end of the socket
634 // from the zygote. We must keep it open until the very end of the zygote's
635 // lifetime, even though we don't explicitly use it.
636 extra_fds
.push_back(sancov_socket_fds
[1]);
639 int sandbox_flags
= linux_sandbox
->GetStatus();
640 bool setuid_sandbox_engaged
= sandbox_flags
& kSandboxLinuxSUID
;
641 CHECK_EQ(must_enable_setuid_sandbox
, setuid_sandbox_engaged
);
643 Zygote
zygote(sandbox_flags
, fork_delegates
.Pass(), extra_children
,
645 // This function call can return multiple times, once per fork().
646 return zygote
.ProcessRequests();
649 } // namespace content