okajima@debian:~$ sudo modprobe unionfs okajima@debian:~$ sudo mount -t tmpfs none /mnt okajima@debian:~$ sudo mount -t unionfs -o dirs=/mnt:/JAIL/etch=ro none /mnt1 okajima@debian:~$ sudo chroot /mnt1 root@debian:/# ls -la total 96 drwxrwxrwt 20 root root 40 Jun 4 13:26 . drwxrwxrwt 20 root root 40 Jun 4 13:26 .. drwxr-xr-x 2 root root 4096 May 28 10:03 bin drwxr-xr-x 2 root root 4096 May 5 16:23 boot drwxr-xr-x 10 root root 28672 May 28 18:55 dev drwxr-xr-x 51 root root 4096 Jun 1 09:11 etc drwxr-xr-x 3 root root 4096 May 28 06:33 home drwxr-xr-x 2 root root 4096 May 28 02:55 initrd drwxr-xr-x 11 root root 4096 May 28 10:03 lib drwxr-xr-x 2 root root 4096 May 28 02:55 media drwxr-xr-x 2 root root 4096 May 5 16:23 mnt drwxr-xr-x 2 root root 4096 May 28 02:55 opt drwxr-xr-x 2 root root 4096 May 5 16:23 proc drwxr-xr-x 2 root root 4096 May 29 12:16 root drwxr-xr-x 2 root root 4096 May 28 10:03 sbin drwxr-xr-x 2 root root 4096 May 28 02:55 srv drwxr-xr-x 2 root root 4096 Mar 27 13:42 sys drwxrwxrwt 5 root root 4096 May 29 12:46 tmp drwxr-xr-x 11 root root 4096 May 28 03:24 usr drwxr-xr-x 13 root root 4096 May 28 02:55 var root@debian:/# mount -t proc none /proc root@debian:/# strace ls -la execve("/bin/ls", ["ls", "-la"], [/* 18 vars */]) = 0 uname({sys="Linux", node="debian", ...}) = 0 brk(0) = 0x805c000 access("/etc/ld.so.nohwcap", F_OK) = -1 ENOENT (No such file or directory) mmap2(NULL, 8192, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0xb7fb0000 access("/etc/ld.so.preload", R_OK) = -1 ENOENT (No such file or directory) open("/etc/ld.so.cache", O_RDONLY) = 3 fstat64(3, {st_mode=S_IFREG|0644, st_size=12000, ...}) = 0 mmap2(NULL, 12000, PROT_READ, MAP_PRIVATE, 3, 0) = 0xb7fad000 close(3) = 0 access("/etc/ld.so.nohwcap", F_OK) = -1 ENOENT (No such file or directory) open("/lib/tls/librt.so.1", O_RDONLY) = 3 read(3, "\177ELF\1\1\1\0\0\0\0\0\0\0\0\0\3\0\3\0\1\0\0\0`\35\0\000"..., 512) = 512 fstat64(3, {st_mode=S_IFREG|0644, st_size=30612, ...}) = 0 mmap2(NULL, 29264, PROT_READ|PROT_EXEC, MAP_PRIVATE|MAP_DENYWRITE, 3, 0) = 0xb7fa5000 mmap2(0xb7fab000, 8192, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_FIXED|MAP_DENYWRITE, 3, 0x6) = 0xb7fab000 close(3) = 0 access("/etc/ld.so.nohwcap", F_OK) = -1 ENOENT (No such file or directory) open("/lib/libacl.so.1", O_RDONLY) = 3 read(3, "\177ELF\1\1\1\0\0\0\0\0\0\0\0\0\3\0\3\0\1\0\0\0\320\23"..., 512) = 512 fstat64(3, {st_mode=S_IFREG|0644, st_size=22964, ...}) = 0 mmap2(NULL, 25936, PROT_READ|PROT_EXEC, MAP_PRIVATE|MAP_DENYWRITE, 3, 0) = 0xb7f9e000 mmap2(0xb7fa4000, 4096, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_FIXED|MAP_DENYWRITE, 3, 0x5) = 0xb7fa4000 close(3) = 0 access("/etc/ld.so.nohwcap", F_OK) = -1 ENOENT (No such file or directory) open("/lib/libselinux.so.1", O_RDONLY) = 3 read(3, "\177ELF\1\1\1\0\0\0\0\0\0\0\0\0\3\0\3\0\1\0\0\0\3601\0"..., 512) = 512 fstat64(3, {st_mode=S_IFREG|0644, st_size=75220, ...}) = 0 mmap2(NULL, 80624, PROT_READ|PROT_EXEC, MAP_PRIVATE|MAP_DENYWRITE, 3, 0) = 0xb7f8a000 mmap2(0xb7f9c000, 8192, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_FIXED|MAP_DENYWRITE, 3, 0x11) = 0xb7f9c000 close(3) = 0 access("/etc/ld.so.nohwcap", F_OK) = -1 ENOENT (No such file or directory) open("/lib/tls/libc.so.6", O_RDONLY) = 3 read(3, "\177ELF\1\1\1\0\0\0\0\0\0\0\0\0\3\0\3\0\1\0\0\0\260O\1"..., 512) = 512 fstat64(3, {st_mode=S_IFREG|0755, st_size=1270928, ...}) = 0 mmap2(NULL, 4096, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0xb7f89000 mmap2(NULL, 1276892, PROT_READ|PROT_EXEC, MAP_PRIVATE|MAP_DENYWRITE, 3, 0) = 0xb7e51000 mmap2(0xb7f7f000, 32768, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_FIXED|MAP_DENYWRITE, 3, 0x12e) = 0xb7f7f000 mmap2(0xb7f87000, 7132, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_FIXED|MAP_ANONYMOUS, -1, 0) = 0xb7f87000 close(3) = 0 access("/etc/ld.so.nohwcap", F_OK) = -1 ENOENT (No such file or directory) open("/lib/tls/libpthread.so.0", O_RDONLY) = 3 read(3, "\177ELF\1\1\1\0\0\0\0\0\0\0\0\0\3\0\3\0\1\0\0\0\340G\0"..., 512) = 512 fstat64(3, {st_mode=S_IFREG|0755, st_size=85770, ...}) = 0 mmap2(NULL, 70104, PROT_READ|PROT_EXEC, MAP_PRIVATE|MAP_DENYWRITE, 3, 0) = 0xb7e3f000 mmap2(0xb7e4d000, 8192, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_FIXED|MAP_DENYWRITE, 3, 0xd) = 0xb7e4d000 mmap2(0xb7e4f000, 4568, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_FIXED|MAP_ANONYMOUS, -1, 0) = 0xb7e4f000 close(3) = 0 access("/etc/ld.so.nohwcap", F_OK) = -1 ENOENT (No such file or directory) open("/lib/libattr.so.1", O_RDONLY) = 3 read(3, "\177ELF\1\1\1\0\0\0\0\0\0\0\0\0\3\0\3\0\1\0\0\0`\f\0\000"..., 512) = 512 fstat64(3, {st_mode=S_IFREG|0644, st_size=12840, ...}) = 0 mmap2(NULL, 15796, PROT_READ|PROT_EXEC, MAP_PRIVATE|MAP_DENYWRITE, 3, 0) = 0xb7e3b000 mmap2(0xb7e3e000, 4096, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_FIXED|MAP_DENYWRITE, 3, 0x2) = 0xb7e3e000 close(3) = 0 access("/etc/ld.so.nohwcap", F_OK) = -1 ENOENT (No such file or directory) open("/lib/tls/libdl.so.2", O_RDONLY) = 3 read(3, "\177ELF\1\1\1\0\0\0\0\0\0\0\0\0\3\0\3\0\1\0\0\0\20\f\0"..., 512) = 512 fstat64(3, {st_mode=S_IFREG|0644, st_size=9592, ...}) = 0 mmap2(NULL, 12404, PROT_READ|PROT_EXEC, MAP_PRIVATE|MAP_DENYWRITE, 3, 0) = 0xb7e37000 mmap2(0xb7e39000, 8192, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_FIXED|MAP_DENYWRITE, 3, 0x1) = 0xb7e39000 close(3) = 0 access("/etc/ld.so.nohwcap", F_OK) = -1 ENOENT (No such file or directory) open("/lib/libsepol.so.1", O_RDONLY) = 3 read(3, "\177ELF\1\1\1\0\0\0\0\0\0\0\0\0\3\0\3\0\1\0\0\0\20/\0\000"..., 512) = 512 fstat64(3, {st_mode=S_IFREG|0644, st_size=211424, ...}) = 0 mmap2(NULL, 256800, PROT_READ|PROT_EXEC, MAP_PRIVATE|MAP_DENYWRITE, 3, 0) = 0xb7df8000 mmap2(0xb7e2c000, 4096, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_FIXED|MAP_DENYWRITE, 3, 0x33) = 0xb7e2c000 mmap2(0xb7e2d000, 39712, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_FIXED|MAP_ANONYMOUS, -1, 0) = 0xb7e2d000 close(3) = 0 mmap2(NULL, 4096, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0xb7df7000 mmap2(NULL, 4096, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0xb7df6000 mprotect(0xb7f7f000, 20480, PROT_READ) = 0 set_thread_area({entry_number:-1 -> 6, base_addr:0xb7df66c0, limit:1048575, seg_32bit:1, contents:0, read_exec_only:0, limit_in_pages:1, seg_not_present:0, useable:1}) = 0 munmap(0xb7fad000, 12000) = 0 set_tid_address(0xb7df6708) = 4226 rt_sigaction(SIGRTMIN, {0xb7e43360, [], SA_RESTORER|SA_SIGINFO, 0xb7e4a650}, NULL, 8) = 0 rt_sigaction(SIGRT_1, {0xb7e433e0, [], SA_RESTORER|SA_RESTART|SA_SIGINFO, 0xb7e4a650}, NULL, 8) = 0 rt_sigprocmask(SIG_UNBLOCK, [RTMIN RT_1], NULL, 8) = 0 getrlimit(RLIMIT_STACK, {rlim_cur=8192*1024, rlim_max=RLIM_INFINITY}) = 0 _sysctl({{CTL_KERN, KERN_VERSION}, 2, 0xbfbc3a40, 31, (nil), 0}) = 0 access("/etc/selinux/", F_OK) = -1 ENOENT (No such file or directory) brk(0) = 0x805c000 brk(0x807d000) = 0x807d000 open("/proc/mounts", O_RDONLY|O_LARGEFILE) = 3 fstat64(3, {st_mode=S_IFREG|0444, st_size=0, ...}) = 0 mmap2(NULL, 4096, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0xb7faf000 read(3, Message from syslogd@localhost at Sun Jun 4 22:26:14 2006 ... localhost kernel: [4294732.001000] Oops: 0000 [#1] +++ killed by SIGSEGV +++ Process 4226 detached root@debian:/# Message from syslogd@localhost at Sun Jun 4 22:26:14 2006 ... localhost kernel: [4294732.001000] CPU: 0 Message from syslogd@localhost at Sun Jun 4 22:26:14 2006 ... localhost kernel: [4294732.001000] eax: ffffffea ebx: 0000000a ecx: ffffffea edx: fffffffe Message from syslogd@localhost at Sun Jun 4 22:26:14 2006 ... localhost kernel: [4294732.001000] esi: c8d9b017 edi: 00000000 ebp: c8d9bfff esp: c8cf6ec0 Message from syslogd@localhost at Sun Jun 4 22:26:14 2006 ... localhost kernel: [4294732.001000] ds: 007b es: 007b ss: 0068 Message from syslogd@localhost at Sun Jun 4 22:26:14 2006 ... localhost kernel: [4294732.001000] Process ls (pid: 4226, veid=0, threadinfo=c8cf6000 task=c9dab890) Message from syslogd@localhost at Sun Jun 4 22:26:14 2006 ... localhost kernel: [4294732.001000] Stack: <0>ffffffff ffffffff ca385640 00000000 00000000 00000001 c01793db c8d9b017 Message from syslogd@localhost at Sun Jun 4 22:26:14 2006 ... localhost kernel: [4294732.001000] 00000fe9 cc972556 c8cf6f00 ca779000 cc96b7c8 ca385640 cc972555 ffffffea Message from syslogd@localhost at Sun Jun 4 22:26:14 2006 ... localhost kernel: [4294732.001000] cc972549 c8ab1000 00000000 c0464428 cbee2dc0 ca385640 c8ab1ffe c017545c Message from syslogd@localhost at Sun Jun 4 22:26:14 2006 ... localhost kernel: [4294732.001000] Call Trace: <0> [seq_printf+35/68] <0> [pg0+205440968/1067971584] <0> [show_vfsmnt+340/428] <0> [seq_read+427/652] <0> [vfs_read+135/296] <0> [sys_read+59/104] <0> [syscall_call+7/11] Message from syslogd@localhost at Sun Jun 4 22:26:14 2006 ... localhost kernel: [4294732.001000] Code: 44 24 04 08 00 00 00 83 cf 01 eb d4 8b 44 24 28 83 44 24 28 04 8b 08 81 f9 ff 0f 00 00 77 05 b9 d9 86 3f c0 8b 14 24 89 c8 eb 06 <80> 38 00 74 07 40 4a 83 fa ff 75 f4 29 c8 83 e7 10 89 c3 75 20 Message from syslogd@localhost at Sun Jun 4 22:26:14 2006 ... localhost kernel: [4294732.001000] EIP is at vsnprintf+0x302/0x48c