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H.J. Lu d8ea0d0168 Add an internal wrapper for clone, clone2 and clone3
The clone3 system call (since Linux 5.3) provides a superset of the
functionality of clone and clone2.  It also provides a number of API
improvements, including the ability to specify the size of the child's
stack area which can be used by kernel to compute the shadow stack size
when allocating the shadow stack.  Add:

extern int __clone_internal (struct clone_args *__cl_args,
			     int (*__func) (void *__arg), void *__arg);

to provide an abstract interface for clone, clone2 and clone3.

1. Simplify stack management for thread creation by passing both stack
base and size to create_thread.
2. Consolidate clone vs clone2 differences into a single file.
3. Call __clone3 if HAVE_CLONE3_WAPPER is defined.  If __clone3 returns
-1 with ENOSYS, fall back to clone or clone2.
4. Use only __clone_internal to clone a thread.  Since the stack size
argument for create_thread is now unconditional, always pass stack size
to create_thread.
5. Enable the public clone3 wrapper in the future after it has been
added to all targets.

NB: Sandbox will return ENOSYS on clone3 in both Chromium:

The following revision refers to this bug:
  218438259d

commit 218438259dd795456f0a48f67cbe5b4e520db88b
Author: Matthew Denton <mpdenton@chromium.org>
Date: Thu Jun 03 20:06:13 2021

Linux sandbox: return ENOSYS for clone3

Because clone3 uses a pointer argument rather than a flags argument, we
cannot examine the contents with seccomp, which is essential to
preventing sandboxed processes from starting other processes. So, we
won't be able to support clone3 in Chromium. This CL modifies the
BPF policy to return ENOSYS for clone3 so glibc always uses the fallback
to clone.

Bug: 1213452
Change-Id: I7c7c585a319e0264eac5b1ebee1a45be2d782303
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2936184
Reviewed-by: Robert Sesek <rsesek@chromium.org>
Commit-Queue: Matthew Denton <mpdenton@chromium.org>
Cr-Commit-Position: refs/heads/master@{#888980}

[modify] https://crrev.com/218438259dd795456f0a48f67cbe5b4e520db88b/sandbox/linux/seccomp-bpf-helpers/baseline_policy.cc

and Firefox:

https://hg.mozilla.org/integration/autoland/rev/ecb4011a0c76

Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
2021-07-14 06:33:58 -07:00
argp argp: Avoid undefined behaviour when invoking qsort(). 2021-02-04 16:44:29 -03:00
assert Update copyright dates with scripts/update-copyrights 2021-01-02 12:17:34 -08:00
benchtests benchtests: Fixed bench-memcpy-random: buf1: mprotect failed 2021-05-26 12:01:06 +01:00
bits Update floating-point feature test macro handling for C2X 2021-06-01 14:22:06 +00:00
catgets Update copyright dates not handled by scripts/update-copyrights. 2021-01-02 12:17:34 -08:00
ChangeLog.old Prepare for glibc 2.33 release 2021-02-01 14:15:33 -03:00
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csu Force building with -fno-common 2021-07-09 20:09:14 +02:00
ctype Update copyright dates with scripts/update-copyrights 2021-01-02 12:17:34 -08:00
debug Remove all usage of @BASH@ or ${BASH} in installed files, and hardcode /bin/bash instead 2021-05-12 07:47:11 +05:30
dirent Update copyright dates with scripts/update-copyrights 2021-01-02 12:17:34 -08:00
dlfcn elf: Clean up GLIBC_PRIVATE exports of internal libdl symbols 2021-07-07 08:41:24 +02:00
elf Force building with -fno-common 2021-07-09 20:09:14 +02:00
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gnulib Update copyright dates with scripts/update-copyrights 2021-01-02 12:17:34 -08:00
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gshadow Update copyright dates with scripts/update-copyrights 2021-01-02 12:17:34 -08:00
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htl htl: Let libc call __pthread_mutex_{,try,un}lock 2021-07-13 23:36:58 +02:00
hurd hurd: Export _hurd_libc_proc_init 2021-04-12 00:23:36 +02:00
iconv libio: Replace internal _IO_getdelim symbol with __getdelim 2021-07-07 18:33:52 +02:00
iconvdata Reinstate gconv-modules as the default configuration file 2021-06-14 18:38:09 +05:30
include Add an internal wrapper for clone, clone2 and clone3 2021-07-14 06:33:58 -07:00
inet inet: Add hidden prototype for __inet_network 2021-07-07 18:33:52 +02:00
intl Use 64 bit time_t stat internally 2021-06-22 12:09:52 -03:00
io io: Add closefrom [BZ #10353] 2021-07-08 14:08:14 -03:00
libio libio: Replace internal _IO_getdelim symbol with __getdelim 2021-07-07 18:33:52 +02:00
locale Use 64 bit time_t stat internally 2021-06-22 12:09:52 -03:00
localedata Reinstate gconv-modules as the default configuration file 2021-06-14 18:38:09 +05:30
login login: Move libutil into libc 2021-06-30 08:43:37 +02:00
mach Update copyright dates with scripts/update-copyrights 2021-01-02 12:17:34 -08:00
malloc mcheck: Align struct hdr to MALLOC_ALIGNMENT bytes [BZ #28068] 2021-07-12 18:13:32 -07:00
manual Define PTHREAD_STACK_MIN to sysconf(_SC_THREAD_STACK_MIN) 2021-07-09 15:10:35 -07:00
math Update floating-point feature test macro handling for C2X 2021-06-01 14:22:06 +00:00
mathvec Update copyright dates with scripts/update-copyrights 2021-01-02 12:17:34 -08:00
misc Force building with -fno-common 2021-07-09 20:09:14 +02:00
nis nis: nis_local_group may read from __nisgroup[-1] (bug 28075) 2021-07-12 07:58:07 +02:00
nptl Add an internal wrapper for clone, clone2 and clone3 2021-07-14 06:33:58 -07:00
nptl_db nptl_db: Re-use the ELF-to-abilist converter for ABI checking 2021-06-29 22:17:08 +02:00
nscd Use 64 bit time_t stat internally 2021-06-22 12:09:52 -03:00
nss nss: Fix build error with --disable-nscd 2021-07-14 10:17:49 +02:00
po Update translations 2021-02-01 14:15:16 -03:00
posix posix: Ignore non opened files on tst-spawn5 2021-07-13 14:09:03 -03:00
pwd Annotate additional APIs with GCC attribute access. 2021-05-06 11:01:05 -06:00
resolv Force building with -fno-common 2021-07-09 20:09:14 +02:00
resource y2038: Add support for 64-bit time on legacy ABIs 2021-06-15 10:42:11 -03:00
rt Linux: Cleanups after librt move 2021-06-28 09:51:01 +02:00
scripts build-many-glibcs.py: Add glibcs-arm-linux-gnueabihf-thumb 2021-07-09 10:59:22 +02:00
setjmp nptl: Move __pthread_unwind_next into libc 2021-04-21 19:49:50 +02:00
shadow Update copyright dates with scripts/update-copyrights 2021-01-02 12:17:34 -08:00
signal y2038: Add support for 64-bit time on legacy ABIs 2021-06-15 10:42:11 -03:00
socket y2038: Add support for 64-bit time on legacy ABIs 2021-06-15 10:42:11 -03:00
soft-fp soft-fp: Add __extendhfsf2/__extendhfdf2, __truncsfhf2/__truncdfhf2, __eqhf2/__nehf2 2021-07-07 08:01:32 -07:00
stdio-common libio: Replace internal _IO_getdelim symbol with __getdelim 2021-07-07 18:33:52 +02:00
stdlib Define PTHREAD_STACK_MIN to sysconf(_SC_THREAD_STACK_MIN) 2021-07-09 15:10:35 -07:00
string String: Add three more overflow tests cases to test-strnlen.c 2021-06-24 19:14:15 -04:00
sunrpc Force building with -fno-common 2021-07-09 20:09:14 +02:00
support support: Replace _SC_MINSIGSTKSZ with _SC_SIGSTKSZ 2021-07-11 07:57:31 -07:00
sysdeps Add an internal wrapper for clone, clone2 and clone3 2021-07-14 06:33:58 -07:00
sysvipc Linux: Cleanups after librt move 2021-06-28 09:51:01 +02:00
termios Update copyright dates with scripts/update-copyrights 2021-01-02 12:17:34 -08:00
time Linux: Cleanups after librt move 2021-06-28 09:51:01 +02:00
timezone Remove all usage of @BASH@ or ${BASH} in installed files, and hardcode /bin/bash instead 2021-05-12 07:47:11 +05:30
wcsmbs Enable support for GCC 11 -Wmismatched-dealloc. 2021-05-16 15:21:18 -06:00
wctype Update copyright dates with scripts/update-copyrights 2021-01-02 12:17:34 -08:00
.gitattributes Assume __NR_openat is always defined 2016-03-23 23:35:08 +01:00
.gitignore Add *.pyc to .gitignore 2015-05-18 15:26:26 +05:30
abi-tags Remove the bulk of the NaCl port. 2017-05-20 08:09:10 -04:00
aclocal.m4 configure: Replaced obsolete AC_TRY_COMPILE 2021-06-04 10:16:00 -03:00
config.h.in Add build option to disable usage of scv on powerpc 2021-06-10 16:23:25 -03:00
config.make.in Add pthread-in-libc, libpthread-routines-var, librt-routines-var 2021-05-03 08:13:32 +02:00
configure Add build option to disable usage of scv on powerpc 2021-06-10 16:23:25 -03:00
configure.ac Add build option to disable usage of scv on powerpc 2021-06-10 16:23:25 -03:00
COPYING Update to latest versions of GPL-2.0 and LGPL-2.1 2013-09-09 12:52:48 +10:00
COPYING.LIB Update to latest versions of GPL-2.0 and LGPL-2.1 2013-09-09 12:52:48 +10:00
extra-lib.mk Rename cppflags-iterator.mk to libof-iterator.mk, remove extra-modules.mk. 2017-05-09 07:06:29 -04:00
gen-locales.mk Improve gen-locales.mk and gen-locale.sh to make test files with @ options work 2018-02-27 17:01:57 +01:00
INSTALL Add build option to disable usage of scv on powerpc 2021-06-10 16:23:25 -03:00
libc-abis riscv: support GNU indirect function 2021-01-10 21:25:13 -05:00
libof-iterator.mk Rename cppflags-iterator.mk to libof-iterator.mk, remove extra-modules.mk. 2017-05-09 07:06:29 -04:00
LICENSES Prefer https to http for gnu.org and fsf.org URLs 2019-09-07 02:43:31 -07:00
MAINTAINERS Add MAINTAINERS 2017-05-11 13:38:30 -04:00
Makeconfig Force building with -fno-common 2021-07-09 20:09:14 +02:00
Makefile Install shared objects under their ABI names 2021-06-28 08:33:57 +02:00
Makefile.help Update copyright dates with scripts/update-copyrights 2021-01-02 12:17:34 -08:00
Makefile.in New make target to only build benchmark binaries 2016-04-20 10:23:28 +05:30
Makerules Install shared objects under their ABI names 2021-06-28 08:33:57 +02:00
NEWS Define PTHREAD_STACK_MIN to sysconf(_SC_THREAD_STACK_MIN) 2021-07-09 15:10:35 -07:00
o-iterator.mk
README Documentation for the RISC-V 32-bit port 2020-08-27 08:17:44 -07:00
Rules Add mcheck tests to malloc 2021-07-02 17:03:42 +05:30
shlib-versions Remove --enable-obsolete-nsl configure flag 2020-07-08 17:25:57 +02:00
test-skeleton.c Update copyright dates with scripts/update-copyrights 2021-01-02 12:17:34 -08:00
version.h Fix version.h for glibc 2.34 development 2021-02-02 08:22:25 -03:00

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