Gecko [ 167.86.127.34 ]

Name	Size	Permission
js	[ DIR ]	drwxr-xr-x
asm9_unix1_amd64.s	1.02 KB	-rw-r--r--
asm9_unix2_amd64.s	1.2 KB	-rw-r--r--
asm_aix_ppc64.s	540 B	-rw-r--r--
asm_darwin_386.s	2.5 KB	-rw-r--r--
asm_darwin_amd64.s	2.82 KB	-rw-r--r--
asm_darwin_arm.s	2.81 KB	-rw-r--r--
asm_darwin_arm64.s	2.71 KB	-rw-r--r--
asm_freebsd_arm.s	2.96 KB	-rw-r--r--
asm_freebsd_arm64.s	2.68 KB	-rw-r--r--
asm_linux_386.s	4.67 KB	-rw-r--r--
asm_linux_amd64.s	3.21 KB	-rw-r--r--
asm_linux_arm.s	3.63 KB	-rw-r--r--
asm_linux_arm64.s	2.73 KB	-rw-r--r--
asm_linux_mips64x.s	2.28 KB	-rw-r--r--
asm_linux_mipsx.s	3.28 KB	-rw-r--r--
asm_linux_ppc64x.s	2.66 KB	-rw-r--r--
asm_linux_riscv64.s	2.46 KB	-rw-r--r--
asm_linux_s390x.s	4.19 KB	-rw-r--r--
asm_netbsd_arm.s	2.85 KB	-rw-r--r--
asm_netbsd_arm64.s	2.77 KB	-rw-r--r--
asm_openbsd_arm.s	3.22 KB	-rw-r--r--
asm_openbsd_arm64.s	2.49 KB	-rw-r--r--
asm_plan9_386.s	3.14 KB	-rw-r--r--
asm_plan9_amd64.s	3.06 KB	-rw-r--r--
asm_plan9_arm.s	3.25 KB	-rw-r--r--
asm_solaris_amd64.s	1.79 KB	-rw-r--r--
asm_unix_386.s	2.74 KB	-rw-r--r--
asm_unix_amd64.s	2.08 KB	-rw-r--r--
asm_windows.s	384 B	-rw-r--r--
bpf_bsd.go	4.61 KB	-rw-r--r--
bpf_darwin.go	3.97 KB	-rw-r--r--
const_plan9.go	1.2 KB	-rw-r--r--
creds_test.go	3.26 KB	-rw-r--r--
dir_plan9.go	5.62 KB	-rw-r--r--
dirent.go	3 KB	-rw-r--r--
dirent_test.go	3.28 KB	-rw-r--r--
dll_windows.go	9.72 KB	-rw-r--r--
endian_big.go	239 B	-rw-r--r--
endian_little.go	273 B	-rw-r--r--
env_plan9.go	2.15 KB	-rw-r--r--
env_unix.go	2.77 KB	-rw-r--r--
env_windows.go	1.75 KB	-rw-r--r--
errors_plan9.go	1.61 KB	-rw-r--r--
exec_aix_test.go	816 B	-rw-r--r--
exec_bsd.go	6.36 KB	-rw-r--r--
exec_darwin.go	6.76 KB	-rw-r--r--
exec_libc.go	6.96 KB	-rw-r--r--
exec_linux.go	18.34 KB	-rw-r--r--
exec_linux_test.go	18.81 KB	-rw-r--r--
exec_plan9.go	13.19 KB	-rw-r--r--
exec_solaris_test.go	808 B	-rw-r--r--
exec_unix.go	8.13 KB	-rw-r--r--
exec_unix_test.go	3.89 KB	-rw-r--r--
exec_windows.go	7.64 KB	-rw-r--r--
export_freebsd_test.go	304 B	-rw-r--r--
export_linux_test.go	252 B	-rw-r--r--
export_test.go	193 B	-rw-r--r--
export_unix_test.go	341 B	-rw-r--r--
flock.go	691 B	-rw-r--r--
flock_aix.go	564 B	-rw-r--r--
flock_darwin.go	405 B	-rw-r--r--
flock_linux_32bit.go	481 B	-rw-r--r--
forkpipe.go	501 B	-rw-r--r--
forkpipe2.go	276 B	-rw-r--r--
fs_js.go	10.46 KB	-rw-r--r--
getdirentries_test.go	2.18 KB	-rw-r--r--
lsf_linux.go	2.12 KB	-rw-r--r--
mkall.sh	12.49 KB	-rwxr-xr-x
mkasm_darwin.go	1.66 KB	-rw-r--r--
mkerrors.sh	10.65 KB	-rwxr-xr-x
mkpost.go	1.99 KB	-rw-r--r--
mksyscall.pl	9.52 KB	-rwxr-xr-x
mksyscall_libc.pl	7.8 KB	-rwxr-xr-x
mksyscall_windows.go	707 B	-rw-r--r--
mksysctl_openbsd.pl	5.04 KB	-rwxr-xr-x
mksysnum_darwin.pl	578 B	-rwxr-xr-x
mksysnum_dragonfly.pl	866 B	-rwxr-xr-x
mksysnum_freebsd.pl	1.35 KB	-rwxr-xr-x
mksysnum_linux.pl	1.26 KB	-rwxr-xr-x
mksysnum_netbsd.pl	1.01 KB	-rwxr-xr-x
mksysnum_openbsd.pl	871 B	-rwxr-xr-x
mksysnum_plan9.sh	459 B	-rwxr-xr-x
mmap_unix_test.go	544 B	-rw-r--r--
msan.go	409 B	-rw-r--r--
msan0.go	341 B	-rw-r--r--
net.go	1.19 KB	-rw-r--r--
net_js.go	2.11 KB	-rw-r--r--
netlink_linux.go	4.67 KB	-rw-r--r--
pwd_plan9.go	1.55 KB	-rw-r--r--
route_bsd.go	9.09 KB	-rw-r--r--
route_darwin.go	2.01 KB	-rw-r--r--
route_dragonfly.go	2.61 KB	-rw-r--r--
route_freebsd.go	2.67 KB	-rw-r--r--
route_freebsd_32bit.go	1.29 KB	-rw-r--r--
route_freebsd_64bit.go	724 B	-rw-r--r--
route_netbsd.go	1.43 KB	-rw-r--r--
route_openbsd.go	1.46 KB	-rw-r--r--
security_windows.go	10.12 KB	-rw-r--r--
setuidgid_32_linux.go	306 B	-rw-r--r--
setuidgid_linux.go	302 B	-rw-r--r--
sock_cloexec_linux.go	632 B	-rw-r--r--
sockcmsg_dragonfly.go	547 B	-rw-r--r--
sockcmsg_linux.go	1.12 KB	-rw-r--r--
sockcmsg_unix.go	2.56 KB	-rw-r--r--
sockcmsg_unix_other.go	957 B	-rw-r--r--
str.go	549 B	-rw-r--r--
syscall.go	3.72 KB	-rw-r--r--
syscall_aix.go	17.83 KB	-rw-r--r--
syscall_aix_ppc64.go	405 B	-rw-r--r--
syscall_bsd.go	14.07 KB	-rw-r--r--
syscall_bsd_test.go	1.16 KB	-rw-r--r--
syscall_darwin.go	14.26 KB	-rw-r--r--
syscall_darwin_386.go	2 KB	-rw-r--r--
syscall_darwin_amd64.go	1.92 KB	-rw-r--r--
syscall_darwin_arm.go	2.03 KB	-rw-r--r--
syscall_darwin_arm64.go	1.98 KB	-rw-r--r--
syscall_dragonfly.go	7.98 KB	-rw-r--r--
syscall_dragonfly_amd64.go	1.12 KB	-rw-r--r--
syscall_freebsd.go	15.82 KB	-rw-r--r--
syscall_freebsd_386.go	1.17 KB	-rw-r--r--
syscall_freebsd_amd64.go	1.12 KB	-rw-r--r--
syscall_freebsd_arm.go	1.16 KB	-rw-r--r--
syscall_freebsd_arm64.go	1.12 KB	-rw-r--r--
syscall_freebsd_test.go	1.35 KB	-rw-r--r--
syscall_getwd_bsd.go	453 B	-rw-r--r--
syscall_js.go	6.59 KB	-rw-r--r--
syscall_linux.go	26.05 KB	-rw-r--r--
syscall_linux_386.go	10.91 KB	-rw-r--r--
syscall_linux_amd64.go	5.39 KB	-rw-r--r--
syscall_linux_arm.go	7.47 KB	-rw-r--r--
syscall_linux_arm64.go	6.24 KB	-rw-r--r--
syscall_linux_mips64x.go	6.58 KB	-rw-r--r--
syscall_linux_mipsx.go	7.03 KB	-rw-r--r--
syscall_linux_ppc64x.go	5.21 KB	-rw-r--r--
syscall_linux_riscv64.go	6.4 KB	-rw-r--r--
syscall_linux_s390x.go	8.64 KB	-rw-r--r--
syscall_linux_test.go	10.61 KB	-rw-r--r--
syscall_netbsd.go	7.59 KB	-rw-r--r--
syscall_netbsd_386.go	716 B	-rw-r--r--
syscall_netbsd_amd64.go	709 B	-rw-r--r--
syscall_netbsd_arm.go	716 B	-rw-r--r--
syscall_netbsd_arm64.go	709 B	-rw-r--r--
syscall_openbsd.go	7.06 KB	-rw-r--r--
syscall_openbsd_386.go	715 B	-rw-r--r--
syscall_openbsd_amd64.go	701 B	-rw-r--r--
syscall_openbsd_arm.go	715 B	-rw-r--r--
syscall_openbsd_arm64.go	906 B	-rw-r--r--
syscall_plan9.go	8.94 KB	-rw-r--r--
syscall_plan9_test.go	1.15 KB	-rw-r--r--
syscall_ptrace_test.go	752 B	-rw-r--r--
syscall_solaris.go	15.07 KB	-rw-r--r--
syscall_solaris_amd64.go	487 B	-rw-r--r--
syscall_test.go	1.7 KB	-rw-r--r--
syscall_unix.go	8.3 KB	-rw-r--r--
syscall_unix_test.go	10.61 KB	-rw-r--r--
syscall_windows.go	42.54 KB	-rw-r--r--
syscall_windows_386.go	176 B	-rw-r--r--
syscall_windows_amd64.go	176 B	-rw-r--r--
syscall_windows_test.go	1.8 KB	-rw-r--r--
tables_js.go	19.17 KB	-rw-r--r--
time_fake.go	676 B	-rw-r--r--
time_nofake.go	350 B	-rw-r--r--
timestruct.go	1.13 KB	-rw-r--r--
types_aix.go	3.35 KB	-rw-r--r--
types_darwin.go	4.98 KB	-rw-r--r--
types_dragonfly.go	5.04 KB	-rw-r--r--
types_freebsd.go	6.96 KB	-rw-r--r--
types_linux.go	10.68 KB	-rw-r--r--
types_netbsd.go	4.77 KB	-rw-r--r--
types_openbsd.go	5.04 KB	-rw-r--r--
types_solaris.go	4.88 KB	-rw-r--r--
types_windows.go	26.96 KB	-rw-r--r--
types_windows_386.go	477 B	-rw-r--r--
types_windows_amd64.go	477 B	-rw-r--r--
types_windows_arm.go	477 B	-rw-r--r--
zerrors_aix_ppc64.go	47.16 KB	-rw-r--r--
zerrors_darwin_386.go	55.27 KB	-rw-r--r--
zerrors_darwin_amd64.go	55.27 KB	-rw-r--r--
zerrors_darwin_arm.go	46.08 KB	-rw-r--r--
zerrors_darwin_arm64.go	55.78 KB	-rw-r--r--
zerrors_dragonfly_amd64.go	59.49 KB	-rw-r--r--
zerrors_freebsd_386.go	67.35 KB	-rw-r--r--
zerrors_freebsd_amd64.go	67.4 KB	-rw-r--r--
zerrors_freebsd_arm.go	67.34 KB	-rw-r--r--
zerrors_freebsd_arm64.go	67.41 KB	-rw-r--r--
zerrors_linux_386.go	58.31 KB	-rw-r--r--
zerrors_linux_amd64.go	58.35 KB	-rw-r--r--
zerrors_linux_arm.go	58.83 KB	-rw-r--r--
zerrors_linux_arm64.go	69.52 KB	-rw-r--r--
zerrors_linux_mips.go	70.14 KB	-rw-r--r--
zerrors_linux_mips64.go	69.46 KB	-rw-r--r--
zerrors_linux_mips64le.go	69.46 KB	-rw-r--r--
zerrors_linux_mipsle.go	70.14 KB	-rw-r--r--
zerrors_linux_ppc64.go	71.84 KB	-rw-r--r--
zerrors_linux_ppc64le.go	72.8 KB	-rw-r--r--
zerrors_linux_riscv64.go	71.76 KB	-rw-r--r--
zerrors_linux_s390x.go	74.28 KB	-rw-r--r--
zerrors_netbsd_386.go	67.43 KB	-rw-r--r--
zerrors_netbsd_amd64.go	67.02 KB	-rw-r--r--
zerrors_netbsd_arm.go	66.45 KB	-rw-r--r--
zerrors_netbsd_arm64.go	67.02 KB	-rw-r--r--
zerrors_openbsd_386.go	62.47 KB	-rw-r--r--
zerrors_openbsd_amd64.go	62.43 KB	-rw-r--r--
zerrors_openbsd_arm.go	62.46 KB	-rw-r--r--
zerrors_openbsd_arm64.go	66.36 KB	-rw-r--r--
zerrors_solaris_amd64.go	50.71 KB	-rw-r--r--
zerrors_windows.go	9.97 KB	-rw-r--r--
zerrors_windows_386.go	176 B	-rw-r--r--
zerrors_windows_amd64.go	176 B	-rw-r--r--
zsyscall_aix_ppc64.go	40.02 KB	-rw-r--r--
zsyscall_darwin_386.go	53.97 KB	-rw-r--r--
zsyscall_darwin_386.s	8.65 KB	-rw-r--r--
zsyscall_darwin_amd64.go	53.83 KB	-rw-r--r--
zsyscall_darwin_amd64.s	8.65 KB	-rw-r--r--
zsyscall_darwin_arm.go	53.44 KB	-rw-r--r--
zsyscall_darwin_arm.s	8.56 KB	-rw-r--r--
zsyscall_darwin_arm64.go	53.3 KB	-rw-r--r--
zsyscall_darwin_arm64.s	8.56 KB	-rw-r--r--
zsyscall_dragonfly_amd64.go	30.9 KB	-rw-r--r--
zsyscall_freebsd_386.go	33.55 KB	-rw-r--r--
zsyscall_freebsd_amd64.go	33.41 KB	-rw-r--r--
zsyscall_freebsd_arm.go	33.58 KB	-rw-r--r--
zsyscall_freebsd_arm64.go	33.41 KB	-rw-r--r--
zsyscall_linux_386.go	35.54 KB	-rw-r--r--
zsyscall_linux_amd64.go	40.66 KB	-rw-r--r--
zsyscall_linux_arm.go	39.77 KB	-rw-r--r--
zsyscall_linux_arm64.go	38.92 KB	-rw-r--r--
zsyscall_linux_mips.go	41.52 KB	-rw-r--r--
zsyscall_linux_mips64.go	41.3 KB	-rw-r--r--
zsyscall_linux_mips64le.go	41.3 KB	-rw-r--r--
zsyscall_linux_mipsle.go	41.52 KB	-rw-r--r--
zsyscall_linux_ppc64.go	41.94 KB	-rw-r--r--
zsyscall_linux_ppc64le.go	41.94 KB	-rw-r--r--
zsyscall_linux_riscv64.go	38.95 KB	-rw-r--r--
zsyscall_linux_s390x.go	35.94 KB	-rw-r--r--
zsyscall_netbsd_386.go	29.62 KB	-rw-r--r--
zsyscall_netbsd_amd64.go	29.48 KB	-rw-r--r--
zsyscall_netbsd_arm.go	29.63 KB	-rw-r--r--
zsyscall_netbsd_arm64.go	29.48 KB	-rw-r--r--
zsyscall_openbsd_386.go	30.46 KB	-rw-r--r--
zsyscall_openbsd_amd64.go	30.32 KB	-rw-r--r--
zsyscall_openbsd_arm.go	30.47 KB	-rw-r--r--
zsyscall_openbsd_arm64.go	30.32 KB	-rw-r--r--
zsyscall_plan9_386.go	6.17 KB	-rw-r--r--
zsyscall_plan9_amd64.go	6.17 KB	-rw-r--r--
zsyscall_plan9_arm.go	6.17 KB	-rw-r--r--
zsyscall_solaris_amd64.go	35.79 KB	-rw-r--r--
zsyscall_windows.go	60.53 KB	-rw-r--r--
zsysctl_openbsd.go	11.71 KB	-rw-r--r--
zsysnum_darwin_386.go	14.55 KB	-rw-r--r--
zsysnum_darwin_amd64.go	14.55 KB	-rw-r--r--
zsysnum_darwin_arm.go	12.28 KB	-rw-r--r--
zsysnum_darwin_arm64.go	14.38 KB	-rw-r--r--
zsysnum_dragonfly_amd64.go	22.72 KB	-rw-r--r--
zsysnum_freebsd_386.go	25.65 KB	-rw-r--r--
zsysnum_freebsd_amd64.go	25.65 KB	-rw-r--r--
zsysnum_freebsd_arm.go	25.65 KB	-rw-r--r--
zsysnum_freebsd_arm64.go	36.09 KB	-rw-r--r--
zsysnum_linux_386.go	11.26 KB	-rw-r--r--
zsysnum_linux_amd64.go	10.1 KB	-rw-r--r--
zsysnum_linux_arm.go	11.55 KB	-rw-r--r--
zsysnum_linux_arm64.go	8.95 KB	-rw-r--r--
zsysnum_linux_mips.go	12.1 KB	-rw-r--r--
zsysnum_linux_mips64.go	10.93 KB	-rw-r--r--
zsysnum_linux_mips64le.go	10.93 KB	-rw-r--r--
zsysnum_linux_mipsle.go	12.1 KB	-rw-r--r--
zsysnum_linux_ppc64.go	11.46 KB	-rw-r--r--
zsysnum_linux_ppc64le.go	11.49 KB	-rw-r--r--
zsysnum_linux_riscv64.go	8.88 KB	-rw-r--r--
zsysnum_linux_s390x.go	10.64 KB	-rw-r--r--
zsysnum_netbsd_386.go	25.54 KB	-rw-r--r--
zsysnum_netbsd_amd64.go	25.55 KB	-rw-r--r--
zsysnum_netbsd_arm.go	25.54 KB	-rw-r--r--
zsysnum_netbsd_arm64.go	25.55 KB	-rw-r--r--
zsysnum_openbsd_386.go	14.15 KB	-rw-r--r--
zsysnum_openbsd_amd64.go	14.15 KB	-rw-r--r--
zsysnum_openbsd_arm.go	14.46 KB	-rw-r--r--
zsysnum_openbsd_arm64.go	14.72 KB	-rw-r--r--
zsysnum_plan9.go	1.03 KB	-rw-r--r--
zsysnum_solaris_amd64.go	289 B	-rw-r--r--
zsysnum_windows_386.go	40 B	-rw-r--r--
zsysnum_windows_amd64.go	40 B	-rw-r--r--
ztypes_aix_ppc64.go	4.17 KB	-rw-r--r--
ztypes_darwin_386.go	6.7 KB	-rw-r--r--
ztypes_darwin_amd64.go	6.92 KB	-rw-r--r--
ztypes_darwin_arm.go	6.77 KB	-rw-r--r--
ztypes_darwin_arm64.go	6.92 KB	-rw-r--r--
ztypes_dragonfly_amd64.go	6.7 KB	-rw-r--r--
ztypes_freebsd_386.go	9 KB	-rw-r--r--
ztypes_freebsd_amd64.go	9 KB	-rw-r--r--
ztypes_freebsd_arm.go	9.01 KB	-rw-r--r--
ztypes_freebsd_arm64.go	9 KB	-rw-r--r--
ztypes_linux_386.go	11.55 KB	-rw-r--r--
ztypes_linux_amd64.go	11.92 KB	-rw-r--r--
ztypes_linux_arm.go	11.44 KB	-rw-r--r--
ztypes_linux_arm64.go	10.12 KB	-rw-r--r--
ztypes_linux_mips.go	9.93 KB	-rw-r--r--
ztypes_linux_mips64.go	10.05 KB	-rw-r--r--
ztypes_linux_mips64le.go	10.05 KB	-rw-r--r--
ztypes_linux_mipsle.go	9.93 KB	-rw-r--r--
ztypes_linux_ppc64.go	10.21 KB	-rw-r--r--
ztypes_linux_ppc64le.go	10.35 KB	-rw-r--r--
ztypes_linux_riscv64.go	10.2 KB	-rw-r--r--
ztypes_linux_s390x.go	10.39 KB	-rw-r--r--
ztypes_netbsd_386.go	5.98 KB	-rw-r--r--
ztypes_netbsd_amd64.go	6.17 KB	-rw-r--r--
ztypes_netbsd_arm.go	6.13 KB	-rw-r--r--
ztypes_netbsd_arm64.go	6.17 KB	-rw-r--r--
ztypes_openbsd_386.go	6.73 KB	-rw-r--r--
ztypes_openbsd_amd64.go	6.88 KB	-rw-r--r--
ztypes_openbsd_arm.go	6.84 KB	-rw-r--r--
ztypes_openbsd_arm64.go	6.66 KB	-rw-r--r--
ztypes_solaris_amd64.go	5.56 KB	-rw-r--r--

Code Editor : exec_linux_test.go

// Copyright 2015 The Go Authors. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.

// +build linux

package syscall_test

import (
	"flag"
	"fmt"
	"internal/testenv"
	"io"
	"io/ioutil"
	"os"
	"os/exec"
	"os/user"
	"path/filepath"
	"runtime"
	"strconv"
	"strings"
	"syscall"
	"testing"
	"unsafe"
)

func isDocker() bool {
	_, err := os.Stat("/.dockerenv")
	return err == nil
}

func isLXC() bool {
	return os.Getenv("container") == "lxc"
}

func skipInContainer(t *testing.T) {
	// TODO: the callers of this func are using this func to skip
	// tests when running as some sort of "fake root" that's uid 0
	// but lacks certain Linux capabilities. Most of the Go builds
	// run in privileged containers, though, where root is much
	// closer (if not identical) to the real root. We should test
	// for what we need exactly (which capabilities are active?),
	// instead of just assuming "docker == bad". Then we'd get more test
	// coverage on a bunch of builders too.
	if isDocker() {
		t.Skip("skip this test in Docker container")
	}
	if isLXC() {
		t.Skip("skip this test in LXC container")
	}
}

func skipNoUserNamespaces(t *testing.T) {
	if _, err := os.Stat("/proc/self/ns/user"); err != nil {
		if os.IsNotExist(err) {
			t.Skip("kernel doesn't support user namespaces")
		}
		if os.IsPermission(err) {
			t.Skip("unable to test user namespaces due to permissions")
		}
		t.Fatalf("Failed to stat /proc/self/ns/user: %v", err)
	}
}

func skipUnprivilegedUserClone(t *testing.T) {
	// Skip the test if the sysctl that prevents unprivileged user
	// from creating user namespaces is enabled.
	data, errRead := ioutil.ReadFile("/proc/sys/kernel/unprivileged_userns_clone")
	if errRead != nil || len(data) < 1 || data[0] == '0' {
		t.Skip("kernel prohibits user namespace in unprivileged process")
	}
}

// Check if we are in a chroot by checking if the inode of / is
// different from 2 (there is no better test available to non-root on
// linux).
func isChrooted(t *testing.T) bool {
	root, err := os.Stat("/")
	if err != nil {
		t.Fatalf("cannot stat /: %v", err)
	}
	return root.Sys().(*syscall.Stat_t).Ino != 2
}

func checkUserNS(t *testing.T) {
	skipInContainer(t)
	skipNoUserNamespaces(t)
	if isChrooted(t) {
		// create_user_ns in the kernel (see
		// https://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/tree/kernel/user_namespace.c)
		// forbids the creation of user namespaces when chrooted.
		t.Skip("cannot create user namespaces when chrooted")
	}
	// On some systems, there is a sysctl setting.
	if os.Getuid() != 0 {
		skipUnprivilegedUserClone(t)
	}
	// On Centos 7 make sure they set the kernel parameter user_namespace=1
	// See issue 16283 and 20796.
	if _, err := os.Stat("/sys/module/user_namespace/parameters/enable"); err == nil {
		buf, _ := ioutil.ReadFile("/sys/module/user_namespace/parameters/enabled")
		if !strings.HasPrefix(string(buf), "Y") {
			t.Skip("kernel doesn't support user namespaces")
		}
	}

// On Centos 7.5+, user namespaces are disabled if user.max_user_namespaces = 0
	if _, err := os.Stat("/proc/sys/user/max_user_namespaces"); err == nil {
		buf, errRead := ioutil.ReadFile("/proc/sys/user/max_user_namespaces")
		if errRead == nil && buf[0] == '0' {
			t.Skip("kernel doesn't support user namespaces")
		}
	}

// When running under the Go continuous build, skip tests for
	// now when under Kubernetes. (where things are root but not quite)
	// Both of these are our own environment variables.
	// See Issue 12815.
	if os.Getenv("GO_BUILDER_NAME") != "" && os.Getenv("IN_KUBERNETES") == "1" {
		t.Skip("skipping test on Kubernetes-based builders; see Issue 12815")
	}
}

func whoamiCmd(t *testing.T, uid, gid int, setgroups bool) *exec.Cmd {
	checkUserNS(t)
	cmd := exec.Command("whoami")
	cmd.SysProcAttr = &syscall.SysProcAttr{
		Cloneflags: syscall.CLONE_NEWUSER,
		UidMappings: []syscall.SysProcIDMap{
			{ContainerID: 0, HostID: uid, Size: 1},
		},
		GidMappings: []syscall.SysProcIDMap{
			{ContainerID: 0, HostID: gid, Size: 1},
		},
		GidMappingsEnableSetgroups: setgroups,
	}
	return cmd
}

func testNEWUSERRemap(t *testing.T, uid, gid int, setgroups bool) {
	cmd := whoamiCmd(t, uid, gid, setgroups)
	out, err := cmd.CombinedOutput()
	if err != nil {
		t.Fatalf("Cmd failed with err %v, output: %s", err, out)
	}
	sout := strings.TrimSpace(string(out))
	want := "root"
	if sout != want {
		t.Fatalf("whoami = %q; want %q", out, want)
	}
}

func TestCloneNEWUSERAndRemapRootDisableSetgroups(t *testing.T) {
	if os.Getuid() != 0 {
		t.Skip("skipping root only test")
	}
	testNEWUSERRemap(t, 0, 0, false)
}

func TestCloneNEWUSERAndRemapRootEnableSetgroups(t *testing.T) {
	if os.Getuid() != 0 {
		t.Skip("skipping root only test")
	}
	testNEWUSERRemap(t, 0, 0, true)
}

func TestCloneNEWUSERAndRemapNoRootDisableSetgroups(t *testing.T) {
	if os.Getuid() == 0 {
		t.Skip("skipping unprivileged user only test")
	}
	testNEWUSERRemap(t, os.Getuid(), os.Getgid(), false)
}

func TestCloneNEWUSERAndRemapNoRootSetgroupsEnableSetgroups(t *testing.T) {
	if os.Getuid() == 0 {
		t.Skip("skipping unprivileged user only test")
	}
	cmd := whoamiCmd(t, os.Getuid(), os.Getgid(), true)
	err := cmd.Run()
	if err == nil {
		t.Skip("probably old kernel without security fix")
	}
	if !os.IsPermission(err) {
		t.Fatalf("Unprivileged gid_map rewriting with GidMappingsEnableSetgroups must fail")
	}
}

func TestEmptyCredGroupsDisableSetgroups(t *testing.T) {
	cmd := whoamiCmd(t, os.Getuid(), os.Getgid(), false)
	cmd.SysProcAttr.Credential = &syscall.Credential{}
	if err := cmd.Run(); err != nil {
		t.Fatal(err)
	}
}

func TestUnshare(t *testing.T) {
	skipInContainer(t)
	// Make sure we are running as root so we have permissions to use unshare
	// and create a network namespace.
	if os.Getuid() != 0 {
		t.Skip("kernel prohibits unshare in unprivileged process, unless using user namespace")
	}

path := "/proc/net/dev"
	if _, err := os.Stat(path); err != nil {
		if os.IsNotExist(err) {
			t.Skip("kernel doesn't support proc filesystem")
		}
		if os.IsPermission(err) {
			t.Skip("unable to test proc filesystem due to permissions")
		}
		t.Fatal(err)
	}
	if _, err := os.Stat("/proc/self/ns/net"); err != nil {
		if os.IsNotExist(err) {
			t.Skip("kernel doesn't support net namespace")
		}
		t.Fatal(err)
	}

orig, err := ioutil.ReadFile(path)
	if err != nil {
		t.Fatal(err)
	}
	origLines := strings.Split(strings.TrimSpace(string(orig)), "\n")

cmd := exec.Command("cat", path)
	cmd.SysProcAttr = &syscall.SysProcAttr{
		Unshareflags: syscall.CLONE_NEWNET,
	}
	out, err := cmd.CombinedOutput()
	if err != nil {
		if strings.Contains(err.Error(), "operation not permitted") {
			// Issue 17206: despite all the checks above,
			// this still reportedly fails for some users.
			// (older kernels?). Just skip.
			t.Skip("skipping due to permission error")
		}
		t.Fatalf("Cmd failed with err %v, output: %s", err, out)
	}

// Check there is only the local network interface
	sout := strings.TrimSpace(string(out))
	if !strings.Contains(sout, "lo:") {
		t.Fatalf("Expected lo network interface to exist, got %s", sout)
	}

lines := strings.Split(sout, "\n")
	if len(lines) >= len(origLines) {
		t.Fatalf("Got %d lines of output, want <%d", len(lines), len(origLines))
	}
}

func TestGroupCleanup(t *testing.T) {
	if os.Getuid() != 0 {
		t.Skip("we need root for credential")
	}
	cmd := exec.Command("id")
	cmd.SysProcAttr = &syscall.SysProcAttr{
		Credential: &syscall.Credential{
			Uid: 0,
			Gid: 0,
		},
	}
	out, err := cmd.CombinedOutput()
	if err != nil {
		t.Fatalf("Cmd failed with err %v, output: %s", err, out)
	}
	strOut := strings.TrimSpace(string(out))
	expected := "uid=0(root) gid=0(root)"
	// Just check prefix because some distros reportedly output a
	// context parameter; see https://golang.org/issue/16224.
	// Alpine does not output groups; see https://golang.org/issue/19938.
	if !strings.HasPrefix(strOut, expected) {
		t.Errorf("id command output: %q, expected prefix: %q", strOut, expected)
	}
}

func TestGroupCleanupUserNamespace(t *testing.T) {
	if os.Getuid() != 0 {
		t.Skip("we need root for credential")
	}
	checkUserNS(t)
	cmd := exec.Command("id")
	uid, gid := os.Getuid(), os.Getgid()
	cmd.SysProcAttr = &syscall.SysProcAttr{
		Cloneflags: syscall.CLONE_NEWUSER,
		Credential: &syscall.Credential{
			Uid: uint32(uid),
			Gid: uint32(gid),
		},
		UidMappings: []syscall.SysProcIDMap{
			{ContainerID: 0, HostID: uid, Size: 1},
		},
		GidMappings: []syscall.SysProcIDMap{
			{ContainerID: 0, HostID: gid, Size: 1},
		},
	}
	out, err := cmd.CombinedOutput()
	if err != nil {
		t.Fatalf("Cmd failed with err %v, output: %s", err, out)
	}
	strOut := strings.TrimSpace(string(out))

// Strings we've seen in the wild.
	expected := []string{
		"uid=0(root) gid=0(root) groups=0(root)",
		"uid=0(root) gid=0(root) groups=0(root),65534(nobody)",
		"uid=0(root) gid=0(root) groups=0(root),65534(nogroup)",
		"uid=0(root) gid=0(root) groups=0(root),65534",
		"uid=0(root) gid=0(root) groups=0(root),65534(nobody),65534(nobody),65534(nobody),65534(nobody),65534(nobody),65534(nobody),65534(nobody),65534(nobody),65534(nobody),65534(nobody)", // Alpine; see https://golang.org/issue/19938
		"uid=0(root) gid=0(root) groups=0(root) context=unconfined_u:unconfined_r:unconfined_t:s0-s0:c0.c1023",                                                                               // CentOS with SELinux context, see https://golang.org/issue/34547
	}
	for _, e := range expected {
		if strOut == e {
			return
		}
	}
	t.Errorf("id command output: %q, expected one of %q", strOut, expected)
}

// TestUnshareHelperProcess isn't a real test. It's used as a helper process
// for TestUnshareMountNameSpace.
func TestUnshareMountNameSpaceHelper(*testing.T) {
	if os.Getenv("GO_WANT_HELPER_PROCESS") != "1" {
		return
	}
	defer os.Exit(0)
	if err := syscall.Mount("none", flag.Args()[0], "proc", 0, ""); err != nil {
		fmt.Fprintf(os.Stderr, "unshare: mount %v failed: %v", os.Args, err)
		os.Exit(2)
	}
}

// Test for Issue 38471: unshare fails because systemd has forced / to be shared
func TestUnshareMountNameSpace(t *testing.T) {
	skipInContainer(t)
	// Make sure we are running as root so we have permissions to use unshare
	// and create a network namespace.
	if os.Getuid() != 0 {
		t.Skip("kernel prohibits unshare in unprivileged process, unless using user namespace")
	}

d, err := ioutil.TempDir("", "unshare")
	if err != nil {
		t.Fatalf("tempdir: %v", err)
	}

cmd := exec.Command(os.Args[0], "-test.run=TestUnshareMountNameSpaceHelper", d)
	cmd.Env = []string{"GO_WANT_HELPER_PROCESS=1"}
	cmd.SysProcAttr = &syscall.SysProcAttr{Unshareflags: syscall.CLONE_NEWNS}

o, err := cmd.CombinedOutput()
	if err != nil {
		if strings.Contains(err.Error(), ": permission denied") {
			t.Skipf("Skipping test (golang.org/issue/19698); unshare failed due to permissions: %s, %v", o, err)
		}
		t.Fatalf("unshare failed: %s, %v", o, err)
	}

// How do we tell if the namespace was really unshared? It turns out
	// to be simple: just try to remove the directory. If it's still mounted
	// on the rm will fail with EBUSY. Then we have some cleanup to do:
	// we must unmount it, then try to remove it again.

if err := os.Remove(d); err != nil {
		t.Errorf("rmdir failed on %v: %v", d, err)
		if err := syscall.Unmount(d, syscall.MNT_FORCE); err != nil {
			t.Errorf("Can't unmount %v: %v", d, err)
		}
		if err := os.Remove(d); err != nil {
			t.Errorf("rmdir after unmount failed on %v: %v", d, err)
		}
	}
}

// Test for Issue 20103: unshare fails when chroot is used
func TestUnshareMountNameSpaceChroot(t *testing.T) {
	skipInContainer(t)
	// Make sure we are running as root so we have permissions to use unshare
	// and create a network namespace.
	if os.Getuid() != 0 {
		t.Skip("kernel prohibits unshare in unprivileged process, unless using user namespace")
	}

d, err := ioutil.TempDir("", "unshare")
	if err != nil {
		t.Fatalf("tempdir: %v", err)
	}

// Since we are doing a chroot, we need the binary there,
	// and it must be statically linked.
	x := filepath.Join(d, "syscall.test")
	cmd := exec.Command(testenv.GoToolPath(t), "test", "-c", "-o", x, "syscall")
	cmd.Env = append(os.Environ(), "CGO_ENABLED=0")
	if o, err := cmd.CombinedOutput(); err != nil {
		t.Fatalf("Build of syscall in chroot failed, output %v, err %v", o, err)
	}

cmd = exec.Command("/syscall.test", "-test.run=TestUnshareMountNameSpaceHelper", "/")
	cmd.Env = []string{"GO_WANT_HELPER_PROCESS=1"}
	cmd.SysProcAttr = &syscall.SysProcAttr{Chroot: d, Unshareflags: syscall.CLONE_NEWNS}

// How do we tell if the namespace was really unshared? It turns out
	// to be simple: just try to remove the executable. If it's still mounted
	// on, the rm will fail. Then we have some cleanup to do:
	// we must force unmount it, then try to remove it again.

if err := os.Remove(x); err != nil {
		t.Errorf("rm failed on %v: %v", x, err)
		if err := syscall.Unmount(d, syscall.MNT_FORCE); err != nil {
			t.Fatalf("Can't unmount %v: %v", d, err)
		}
		if err := os.Remove(x); err != nil {
			t.Fatalf("rm failed on %v: %v", x, err)
		}
	}

if err := os.Remove(d); err != nil {
		t.Errorf("rmdir failed on %v: %v", d, err)
	}
}

func TestUnshareUidGidMappingHelper(*testing.T) {
	if os.Getenv("GO_WANT_HELPER_PROCESS") != "1" {
		return
	}
	defer os.Exit(0)
	if err := syscall.Chroot(os.TempDir()); err != nil {
		fmt.Fprintln(os.Stderr, err)
		os.Exit(2)
	}
}

// Test for Issue 29789: unshare fails when uid/gid mapping is specified
func TestUnshareUidGidMapping(t *testing.T) {
	if os.Getuid() == 0 {
		t.Skip("test exercises unprivileged user namespace, fails with privileges")
	}
	checkUserNS(t)
	cmd := exec.Command(os.Args[0], "-test.run=TestUnshareUidGidMappingHelper")
	cmd.Env = append(os.Environ(), "GO_WANT_HELPER_PROCESS=1")
	cmd.SysProcAttr = &syscall.SysProcAttr{
		Unshareflags:               syscall.CLONE_NEWNS | syscall.CLONE_NEWUSER,
		GidMappingsEnableSetgroups: false,
		UidMappings: []syscall.SysProcIDMap{
			{
				ContainerID: 0,
				HostID:      syscall.Getuid(),
				Size:        1,
			},
		},
		GidMappings: []syscall.SysProcIDMap{
			{
				ContainerID: 0,
				HostID:      syscall.Getgid(),
				Size:        1,
			},
		},
	}
	out, err := cmd.CombinedOutput()
	if err != nil {
		t.Fatalf("Cmd failed with err %v, output: %s", err, out)
	}
}

type capHeader struct {
	version uint32
	pid     int32
}

type capData struct {
	effective   uint32
	permitted   uint32
	inheritable uint32
}

const CAP_SYS_TIME = 25
const CAP_SYSLOG = 34

type caps struct {
	hdr  capHeader
	data [2]capData
}

func getCaps() (caps, error) {
	var c caps

// Get capability version
	if _, _, errno := syscall.Syscall(syscall.SYS_CAPGET, uintptr(unsafe.Pointer(&c.hdr)), uintptr(unsafe.Pointer(nil)), 0); errno != 0 {
		return c, fmt.Errorf("SYS_CAPGET: %v", errno)
	}

// Get current capabilities
	if _, _, errno := syscall.Syscall(syscall.SYS_CAPGET, uintptr(unsafe.Pointer(&c.hdr)), uintptr(unsafe.Pointer(&c.data[0])), 0); errno != 0 {
		return c, fmt.Errorf("SYS_CAPGET: %v", errno)
	}

return c, nil
}

func mustSupportAmbientCaps(t *testing.T) {
	var uname syscall.Utsname
	if err := syscall.Uname(&uname); err != nil {
		t.Fatalf("Uname: %v", err)
	}
	var buf [65]byte
	for i, b := range uname.Release {
		buf[i] = byte(b)
	}
	ver := string(buf[:])
	if i := strings.Index(ver, "\x00"); i != -1 {
		ver = ver[:i]
	}
	if strings.HasPrefix(ver, "2.") ||
		strings.HasPrefix(ver, "3.") ||
		strings.HasPrefix(ver, "4.1.") ||
		strings.HasPrefix(ver, "4.2.") {
		t.Skipf("kernel version %q predates required 4.3; skipping test", ver)
	}
}

// TestAmbientCapsHelper isn't a real test. It's used as a helper process for
// TestAmbientCaps.
func TestAmbientCapsHelper(*testing.T) {
	if os.Getenv("GO_WANT_HELPER_PROCESS") != "1" {
		return
	}
	defer os.Exit(0)

caps, err := getCaps()
	if err != nil {
		fmt.Fprintln(os.Stderr, err)
		os.Exit(2)
	}
	if caps.data[0].effective&(1<<uint(CAP_SYS_TIME)) == 0 {
		fmt.Fprintln(os.Stderr, "CAP_SYS_TIME unexpectedly not in the effective capability mask")
		os.Exit(2)
	}
	if caps.data[1].effective&(1<<uint(CAP_SYSLOG&31)) == 0 {
		fmt.Fprintln(os.Stderr, "CAP_SYSLOG unexpectedly not in the effective capability mask")
		os.Exit(2)
	}
}

func TestAmbientCaps(t *testing.T) {
	// Make sure we are running as root so we have permissions to use unshare
	// and create a network namespace.
	if os.Getuid() != 0 {
		t.Skip("kernel prohibits unshare in unprivileged process, unless using user namespace")
	}

testAmbientCaps(t, false)
}

func TestAmbientCapsUserns(t *testing.T) {
	checkUserNS(t)
	testAmbientCaps(t, true)
}

func testAmbientCaps(t *testing.T, userns bool) {
	skipInContainer(t)
	mustSupportAmbientCaps(t)

skipUnprivilegedUserClone(t)

// skip on android, due to lack of lookup support
	if runtime.GOOS == "android" {
		t.Skip("skipping test on android; see Issue 27327")
	}

u, err := user.Lookup("nobody")
	if err != nil {
		t.Fatal(err)
	}
	uid, err := strconv.ParseInt(u.Uid, 0, 32)
	if err != nil {
		t.Fatal(err)
	}
	gid, err := strconv.ParseInt(u.Gid, 0, 32)
	if err != nil {
		t.Fatal(err)
	}

// Copy the test binary to a temporary location which is readable by nobody.
	f, err := ioutil.TempFile("", "gotest")
	if err != nil {
		t.Fatal(err)
	}
	defer os.Remove(f.Name())
	defer f.Close()
	e, err := os.Open(os.Args[0])
	if err != nil {
		t.Fatal(err)
	}
	defer e.Close()
	if _, err := io.Copy(f, e); err != nil {
		t.Fatal(err)
	}
	if err := f.Chmod(0755); err != nil {
		t.Fatal(err)
	}
	if err := f.Close(); err != nil {
		t.Fatal(err)
	}

cmd := exec.Command(f.Name(), "-test.run=TestAmbientCapsHelper")
	cmd.Env = []string{"GO_WANT_HELPER_PROCESS=1"}
	cmd.Stdout = os.Stdout
	cmd.Stderr = os.Stderr
	cmd.SysProcAttr = &syscall.SysProcAttr{
		Credential: &syscall.Credential{
			Uid: uint32(uid),
			Gid: uint32(gid),
		},
		AmbientCaps: []uintptr{CAP_SYS_TIME, CAP_SYSLOG},
	}
	if userns {
		cmd.SysProcAttr.Cloneflags = syscall.CLONE_NEWUSER
		const nobody = 65534
		uid := os.Getuid()
		gid := os.Getgid()
		cmd.SysProcAttr.UidMappings = []syscall.SysProcIDMap{{
			ContainerID: int(nobody),
			HostID:      int(uid),
			Size:        int(1),
		}}
		cmd.SysProcAttr.GidMappings = []syscall.SysProcIDMap{{
			ContainerID: int(nobody),
			HostID:      int(gid),
			Size:        int(1),
		}}

// Set credentials to run as user and group nobody.
		cmd.SysProcAttr.Credential = &syscall.Credential{
			Uid: nobody,
			Gid: nobody,
		}
	}
	if err := cmd.Run(); err != nil {
		t.Fatal(err.Error())
	}
}

${this.title}

Code Editor : exec_linux_test.go