mrunalp

#define _GNU_SOURCE
#include <stdio.h>
#include <stdlib.h>
#include <sys/mount.h>
#include <sys/stat.h>
#include <sys/types.h>
#include <fcntl.h>
#include <sched.h>
#include <unistd.h>
#include <errno.h>

mrunalp

require 'socket'
require 'ipaddr'

# From ioctls.h
SIOCGIFADDR    = 0x8915

def ip_address(iface)
    sock = UDPSocket.new
    buf = [iface,""].pack('a16h16')
    sock.ioctl(SIOCGIFADDR, buf);

mrunalp

package main

import (
	"log"
	"os"
	"syscall"
)

func main() {
	syscall.ForkLock.Lock()

mrunalp

[root@localhost ~]# docker run -it --rm busybox /bin/sh
/ # command -v groupadd
/ # echo $?
127
/ # addgroup -g 1003 container
/ # echo $?
0
/ # adduser -u 1003 -g 1003 container
adduser: uid '1003' in use
/ # echo $?

mrunalp

[root@localhost ~]# docker run -it --rm busybox /bin/sh
/ # command -v groupadd
/ # echo $?
127
/ # addgroup -g 1003 container
/ # echo $?
0
/ # adduser -u 1003 -g 1003 container
adduser: uid '1003' in use
/ # echo $?

mrunalp

{"mount_config":{"mounts":[{"type":"bind","source":"/var/lib/docker/init/dockerinit-1.0.1-dev","destination":"/.dockerinit","private":true},{"type":"bind","source":"/etc/resolv.conf","destination":"/etc/resolv.conf","private":true},{"type":"bind","source":"/var/lib/docker/containers/ff17757403e4b96fbb7a65dafe2dc8a3a21e809e3fa30e5d35d4f767fae267d3/hostname","destination":"/etc/hostname","private":true},{"type":"bind","source":"/var/lib/docker/containers/ff17757403e4b96fbb7a65dafe2dc8a3a21e809e3fa30e5d35d4f767fae267d3/hosts","destination":"/etc/hosts","private":true}],"device_nodes":[{"type":99,"path":"/dev/fuse","major_number":10,"minor_number":229,"cgroup_permissions":"rwm"},{"type":99,"path":"/dev/null","major_number":1,"minor_number":3,"cgroup_permissions":"rwm","file_mode":438},{"type":99,"path":"/dev/zero","major_number":1,"minor_number":5,"cgroup_permissions":"rwm","file_mode":438},{"type":99,"path":"/dev/full","major_number":1,"minor_number":7,"cgroup_permissions":"rwm","file_mode":438},{"type":99,"path

mrunalp

{"mount_config":{"mounts":[{"type":"bind","source":"/var/lib/docker/init/dockerinit-1.0.1-dev","destination":"/.dockerinit","private":true},{"type":"bind","source":"/etc/resolv.conf","destination":"/etc/resolv.conf","private":true},{"type":"bind","source":"/var/lib/docker/containers/ff17757403e4b96fbb7a65dafe2dc8a3a21e809e3fa30e5d35d4f767fae267d3/hostname","destination":"/etc/hostname","private":true},{"type":"bind","source":"/var/lib/docker/containers/ff17757403e4b96fbb7a65dafe2dc8a3a21e809e3fa30e5d35d4f767fae267d3/hosts","destination":"/etc/hosts","private":true}],"device_nodes":[{"type":99,"path":"/dev/fuse","major_number":10,"minor_number":229,"cgroup_permissions":"rwm"},{"type":99,"path":"/dev/null","major_number":1,"minor_number":3,"cgroup_permissions":"rwm","file_mode":438},{"type":99,"path":"/dev/zero","major_number":1,"minor_number":5,"cgroup_permissions":"rwm","file_mode":438},{"type":99,"path":"/dev/full","major_number":1,"minor_number":7,"cgroup_permissions":"rwm","file_mode":438},{"type":99,"path

mrunalp

[root@localhost rootfs]# nsinit exec /bin/bash
2014/06/26 21:50:00 EXEC USERNS
2014/06/26 21:50:00 &{MountConfig:0xc21001e3c0 Hostname:koye User:root WorkingDir: Env:[HOME=/ PATH=/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin HOSTNAME=koye TERM=xterm] Tty:true Namespaces:map[NEWIPC:true NEWNET:true NEWNS:true NEWPID:true NEWUTS:true NEWUSER:true] Capabilities:[CHOWN DAC_OVERRIDE FOWNER MKNOD NET_RAW SETGID SETUID SETFCAP SETPCAP NET_BIND_SERVICE SYS_CHROOT KILL] Networks:[0xc21004e310] Routes:[] Cgroups:0xc21000f6e0 AppArmorProfile: ProcessLabel: RestrictSys:true UidMappings:[{ContainerId:0 HostId:1013 Size:1} {ContainerId:1 HostId:1 Size:1012}] GidMappings:[{ContainerId:0 HostId:1013 Size:1} {ContainerId:1 HostId:1 Size:1012}]}
2014/06/26 21:50:00 1
2014/06/26 21:50:00 proc: &{6 0 0}
2014/06/26 21:50:00 uid: [{ContainerId:0 HostId:1013 Size:1} {ContainerId:1 HostId:1 Size:1012}]
2014/06/26 21:50:00 0 1013 1
1 1 1012
2014/06/26 21:50:00 0 1013 1
1 1 1012

mrunalp

diff -r 9895f9e36435 src/pkg/syscall/exec_linux.go
--- a/src/pkg/syscall/exec_linux.go	Thu Jun 19 10:20:01 2014 +1000
+++ b/src/pkg/syscall/exec_linux.go	Wed Jul 30 14:03:39 2014 -0400
@@ -36,7 +36,7 @@
 // For the same reason compiler does not race instrument it.
 // The calls to RawSyscall are okay because they are assembly
 // functions that do not grow the stack.
-func forkAndExecInChild(argv0 *byte, argv, envv []*byte, chroot, dir *byte, attr *ProcAttr, sys *SysProcAttr, pipe int) (pid int, err Errno) {
+func forkAndExecInChild(argv0 *byte, argv, envv []*byte, chroot, dir *byte, attr *ProcAttr, sys *SysProcAttr, child, parent int) (pid int, err Errno) {
 	// Declare all variables at top in case any

mrunalp

package main

import (
        "log"
        "os"
        "os/exec"
        "syscall"
)

func main() {