Bash can't start a programme that's there and has all the right permissions
- by Rory
This is a gentoo server. There's a programme prog that can't execute. (Yes the execute permission is set)
About the file
$ ls
prog
$ ./prog
bash: ./prog: No such file or directory
$ file prog
prog: ELF 32-bit LSB executable, Intel 80386, version 1 (SYSV), for GNU/Linux 2.2.5, dynamically linked (uses shared libs), not stripped
$ pwd
/usr/local/bin
$ /usr/local/bin/prog
bash: /usr/local/bin/prog: No such file or directory
$ less prog | head
ELF Header:
Magic: 7f 45 4c 46 01 01 01 00 00 00 00 00 00 00 00 00
Class: ELF32
Data: 2's complement, little endian
Version: 1 (current)
OS/ABI: UNIX - System V
ABI Version: 0
Type: EXEC (Executable file)
Machine: Intel 80386
Version: 0x1
I have a fancy less, to show that it's an actual executable, here's some more data:
$ xxd prog |head
0000000: 7f45 4c46 0101 0100 0000 0000 0000 0000 .ELF............
0000010: 0200 0300 0100 0000 c092 0408 3400 0000 ............4...
0000020: 0401 0a00 0000 0000 3400 2000 0700 2800 ........4. ...(.
0000030: 2600 2300 0600 0000 3400 0000 3480 0408 &.#.....4...4...
0000040: 3480 0408 e000 0000 e000 0000 0500 0000 4...............
0000050: 0400 0000 0300 0000 1401 0000 1481 0408 ................
0000060: 1481 0408 1300 0000 1300 0000 0400 0000 ................
0000070: 0100 0000 0100 0000 0000 0000 0080 0408 ................
0000080: 0080 0408 21f1 0500 21f1 0500 0500 0000 ....!...!.......
0000090: 0010 0000 0100 0000 40f1 0500 4081 0a08 ........@...@...
and
$ ls -l prog
-rwxrwxr-x 1 1000 devs 725706 Aug 6 2007 prog
$ ldd prog
not a dynamic executable
$ strace ./prog
1249403877.639076 execve("./prog", ["./prog"], [/* 27 vars */]) = -1 ENOENT (No such file or directory)
1249403877.640645 dup(2) = 3
1249403877.640875 fcntl(3, F_GETFL) = 0x8002 (flags O_RDWR|O_LARGEFILE)
1249403877.641143 fstat(3, {st_mode=S_IFCHR|0620, st_rdev=makedev(136, 0), ...}) = 0
1249403877.641484 mmap(NULL, 4096, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x2b3b8954a000
1249403877.641747 lseek(3, 0, SEEK_CUR) = -1 ESPIPE (Illegal seek)
1249403877.642045 write(3, "strace: exec: No such file or dir"..., 40strace: exec: No such file or directory
) = 40
1249403877.642324 close(3) = 0
1249403877.642531 munmap(0x2b3b8954a000, 4096) = 0
1249403877.642735 exit_group(1) = ?
About the server
FTR the server is a xen domU, and the programme is a closed source linux application. This VM is a copy of another VM that has the same root filesystem (including this programme), that works fine.
I've tried all the above as root and same problem.
Did I mention the root filesystem is mounted over NFS. However it's mounted 'defaults,nosuid', which should include execute. Also I am able to run many other programmes from that mounted drive
/proc/cpuinfo:
processor : 0
vendor_id : GenuineIntel
cpu family : 15
model : 4
model name : Intel(R) Xeon(TM) CPU 3.00GHz
stepping : 1
cpu MHz : 2992.692
cache size : 1024 KB
fpu : yes
fpu_exception : yes
cpuid level : 5
wp : yes
flags : fpu tsc msr pae mce cx8 apic mca cmov pat pse36 clflush dts acpi mmx fxsr sse sse2 ss ht tm syscall nx lm constant_tsc pni monitor ds_cpl cid cx16 xtpr
bogmips : 5989.55
clflush size : 64
cache_alignment : 128
address sizes : 36 bits physical, 48 bits virtual
power management:
Example of a file that I can run
I can run other programmes on that mounted filesystem on that server. For example:
$ ls -l ls
-rwxr-xr-x 1 root root 105576 Jul 25 17:14 ls
$ file ls
ls: ELF 64-bit LSB executable, x86-64, version 1 (SYSV), for GNU/Linux 2.6.9, dynamically linked (uses shared libs), stripped
$ ./ls
attr cat cut echo getfacl ln more
... (you get the idea) ...
rmdir sort tty
$ less ls | head
ELF Header:
Magic: 7f 45 4c 46 02 01 01 00 00 00 00 00 00 00 00 00
Class: ELF64
Data: 2's complement, little endian
Version: 1 (current)
OS/ABI: UNIX - System V
ABI Version: 0
Type: EXEC (Executable file)
Machine: Advanced Micro Devices X86-64
Version: 0x1