This tutorial explains Linux “objdump” command, options and its usage with examples.
objdump – display information from object files.
Description :
objdump displays information about one or more object files. The options control what particular information to display. This information is mostly useful to programmers who are working on the compilation tools, as opposed to programmers who just want their program to compile and work.
At least one of the options -a, -d, -D, -f, -g, -G, -h, -H, -p, -r, -S, -t, -T, -V, or -x must be given to tell objdump what information to show.
Usage :
objdump [options] objfiles
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Options :
-a, –archive-header
If any input files are archives, display the archive header information. The output includes the object file format of each archive member.
–adjust-vma=offset
Add offset to all section headers before dumping information. Useful if the section addresses do not correspond to the symbol table.
-b bfdname, –target=bfdname
Set the binary file format using its binary file descriptor name, bfdname. Use the -h option for a list of supported formats for your system.
-C [style], –demangle[=style] Decode (demangle) low-level symbol names into user-level names, optionally specifying a mangling style. Removes any initial underscores and makes C++ function names readable.
-d, –disassemble
Display assembler mnemonic names for the machine instructions. Disassemble only sections that are expected to contain instructions.
-D, –disassemble-all
Disassemble all sections, not just those expected to contain instructions.
-EB, –endian=big
-EL, –endian=little
Specify whether the object files are big- or little-endian, for disassembling. Useful for disassembling formats such as S-records (printable ASCII versions of object files) that do not include that information.
-f, –file-header
Display overall header summary information.
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–file-start-context
When using -S and displaying source code from a file that hasn’t been displayed yet, include context from the start of the file.
-g, –debugging
Display debugging information.
-G, –stabs
Display any stabs (debugging symbol table entries) information, in addition to the contents of any sections requested.
-h, –section-header, –header
Display section-header summary information.
-H, –help
Display help information and exit.
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-i, –info
Display the architectures and object formats available on your system for use with -b or -m.
-j name, –section=name
Display information for section name.
-l, –line-numbers
Label the display with filename and source code line numbers corresponding to the object code or relocation entries shown. Use with -d, -D, or -r.
-m arch, –architecture=arch
Specify the architecture for disassembling object files. Useful when disassembling files such as S-records that do not include this information.
-M options, –disassembler-options=options
Pass target-specific information to the disassembler. Supported only on some targets.
–no-show-raw-insn
Do not show instructions in hexadecimal when disassembling. This is the default with –prefix-addresses.
-p, –private-headers
Display information specific to the object format. For some formats, no additional information is displayed.
–prefix-addresses
When disassembling, print the complete address on each line.
-r, –reloc
Display relocation entries. With -b or -D, the entries are intermixed with the disassembly.
-R, –dynamic-reloc
Print dynamic relocation entries. Meaningful only for dynamic objects such as certain types of shared libraries.
-s, –full-contents
Display the full contents of any requested sections.
-S, –source
Display source code intermixed with disassembly, if possible. Implies -d.
–show-raw-insn
When disassembling, show instructions in hexadecimal as well as symbolic form. This is the default, except with –prefix-addresses.
–start-address=addr
Start displaying data at the specified address. Applies to -d, -r, and -s.
–stop-address=addr
Stop displaying data at the specified address. Applies to -d, -r, and -s.
-t, –syms
Print symbol table entries.
-T, –dynamic-syms
Print dynamic symbol table entries. Meaningful only for dynamic objects such as certain types of shared libraries.
-V, –version
Print version information and exit.
-w, –wide
Format lines for output devices wider than 80 characters, and do not truncate symbol table names.
-x, –all-headers
Display all available header information. Equivalent to specifying -a -f -h -r -t.
-z, –disassemble-zeroes
Disassemble blocks of zeroes. The default is to skip such blocks.
Examples :
The code used for object files in all the examples is :
$ cat factorial.c
#include<stdio.h>
int main(void)
{
int n = 6;
float f=1;
int i = 1;
for(;i<=n;i++)
f=f*i;
printf("\n Factorial is : [%f]\n",f);
return 0;
}
$ gcc factorial.c1. Display the contents of the overall file header using -f option
$ gcc factorial.c mohakkataria@ubuntu:/tmp$ objdump -f a.out a.out: file format elf64-x86-64 architecture: i386:x86-64, flags 0x00000112: EXEC_P, HAS_SYMS, D_PAGED
2. Display object format specific file header contents using -p option
$ objdump -p a.out
a.out: file format elf64-x86-64
Program Header:
PHDR off 0x0000000000000040 vaddr 0x0000000000400040 paddr 0x0000000000400040 align 2**3
filesz 0x00000000000001f8 memsz 0x00000000000001f8 flags r-x
INTERP off 0x0000000000000238 vaddr 0x0000000000400238 paddr 0x0000000000400238 align 2**0
filesz 0x000000000000001c memsz 0x000000000000001c flags r--
LOAD off 0x0000000000000000 vaddr 0x0000000000400000 paddr 0x0000000000400000 align 2**21
filesz 0x000000000000075c memsz 0x000000000000075c flags r-x
LOAD off 0x0000000000000e10 vaddr 0x0000000000600e10 paddr 0x0000000000600e10 align 2**21
filesz 0x0000000000000230 memsz 0x0000000000000238 flags rw-
DYNAMIC off 0x0000000000000e28 vaddr 0x0000000000600e28 paddr 0x0000000000600e28 align 2**3
filesz 0x00000000000001d0 memsz 0x00000000000001d0 flags rw-
NOTE off 0x0000000000000254 vaddr 0x0000000000400254 paddr 0x0000000000400254 align 2**2
filesz 0x0000000000000044 memsz 0x0000000000000044 flags r--
EH_FRAME off 0x0000000000000650 vaddr 0x0000000000400650 paddr 0x0000000000400650 align 2**2
filesz 0x0000000000000034 memsz 0x0000000000000034 flags r--
STACK off 0x0000000000000000 vaddr 0x0000000000000000 paddr 0x0000000000000000 align 2**3
filesz 0x0000000000000000 memsz 0x0000000000000000 flags rw-
RELRO off 0x0000000000000e10 vaddr 0x0000000000600e10 paddr 0x0000000000600e10 align 2**0
filesz 0x00000000000001f0 memsz 0x00000000000001f0 flags r--
Dynamic Section:
NEEDED libc.so.6
INIT 0x00000000004003e0
FINI 0x0000000000400624
INIT_ARRAY 0x0000000000600e10
INIT_ARRAYSZ 0x0000000000000008
FINI_ARRAY 0x0000000000600e18
FINI_ARRAYSZ 0x0000000000000008
GNU_HASH 0x0000000000400298
STRTAB 0x0000000000400318
SYMTAB 0x00000000004002b8
STRSZ 0x000000000000003f
SYMENT 0x0000000000000018
DEBUG 0x0000000000000000
PLTGOT 0x0000000000601000
PLTRELSZ 0x0000000000000048
PLTREL 0x0000000000000007
JMPREL 0x0000000000400398
RELA 0x0000000000400380
RELASZ 0x0000000000000018
RELAENT 0x0000000000000018
VERNEED 0x0000000000400360
VERNEEDNUM 0x0000000000000001
VERSYM 0x0000000000400358
Version References:
required from libc.so.6:
0x09691a75 0x00 02 GLIBC_2.2.53. Display the contents of the section headers using -h option
There can be various sections in an object file. Information related to them can be printed using -h option.
$ objdump -h a.out
a.out: file format elf64-x86-64
Sections:
Idx Name Size VMA LMA File off Algn
0 .interp 0000001c 0000000000400238 0000000000400238 00000238 2**0
CONTENTS, ALLOC, LOAD, READONLY, DATA
1 .note.ABI-tag 00000020 0000000000400254 0000000000400254 00000254 2**2
CONTENTS, ALLOC, LOAD, READONLY, DATA
2 .note.gnu.build-id 00000024 0000000000400274 0000000000400274 00000274 2**2
CONTENTS, ALLOC, LOAD, READONLY, DATA
3 .gnu.hash 0000001c 0000000000400298 0000000000400298 00000298 2**3
CONTENTS, ALLOC, LOAD, READONLY, DATA
4 .dynsym 00000060 00000000004002b8 00000000004002b8 000002b8 2**3
CONTENTS, ALLOC, LOAD, READONLY, DATA
5 .dynstr 0000003f 0000000000400318 0000000000400318 00000318 2**0
CONTENTS, ALLOC, LOAD, READONLY, DATA
6 .gnu.version 00000008 0000000000400358 0000000000400358 00000358 2**1
CONTENTS, ALLOC, LOAD, READONLY, DATA
7 .gnu.version_r 00000020 0000000000400360 0000000000400360 00000360 2**3
CONTENTS, ALLOC, LOAD, READONLY, DATA
8 .rela.dyn 00000018 0000000000400380 0000000000400380 00000380 2**3
CONTENTS, ALLOC, LOAD, READONLY, DATA
9 .rela.plt 00000048 0000000000400398 0000000000400398 00000398 2**3
CONTENTS, ALLOC, LOAD, READONLY, DATA
10 .init 0000001a 00000000004003e0 00000000004003e0 000003e0 2**2
CONTENTS, ALLOC, LOAD, READONLY, CODE
11 .plt 00000040 0000000000400400 0000000000400400 00000400 2**4
CONTENTS, ALLOC, LOAD, READONLY, CODE
12 .text 000001e4 0000000000400440 0000000000400440 00000440 2**4
CONTENTS, ALLOC, LOAD, READONLY, CODE
13 .fini 00000009 0000000000400624 0000000000400624 00000624 2**2
CONTENTS, ALLOC, LOAD, READONLY, CODE
14 .rodata 00000020 0000000000400630 0000000000400630 00000630 2**2
CONTENTS, ALLOC, LOAD, READONLY, DATA
15 .eh_frame_hdr 00000034 0000000000400650 0000000000400650 00000650 2**2
CONTENTS, ALLOC, LOAD, READONLY, DATA
16 .eh_frame 000000d4 0000000000400688 0000000000400688 00000688 2**3
CONTENTS, ALLOC, LOAD, READONLY, DATA
17 .init_array 00000008 0000000000600e10 0000000000600e10 00000e10 2**3
CONTENTS, ALLOC, LOAD, DATA
18 .fini_array 00000008 0000000000600e18 0000000000600e18 00000e18 2**3
CONTENTS, ALLOC, LOAD, DATA
19 .jcr 00000008 0000000000600e20 0000000000600e20 00000e20 2**3
CONTENTS, ALLOC, LOAD, DATA
20 .dynamic 000001d0 0000000000600e28 0000000000600e28 00000e28 2**3
CONTENTS, ALLOC, LOAD, DATA
21 .got 00000008 0000000000600ff8 0000000000600ff8 00000ff8 2**3
CONTENTS, ALLOC, LOAD, DATA
22 .got.plt 00000030 0000000000601000 0000000000601000 00001000 2**3
CONTENTS, ALLOC, LOAD, DATA
23 .data 00000010 0000000000601030 0000000000601030 00001030 2**3
CONTENTS, ALLOC, LOAD, DATA
24 .bss 00000008 0000000000601040 0000000000601040 00001040 2**2
ALLOC
25 .comment 0000002a 0000000000000000 0000000000000000 00001040 2**0
CONTENTS, READONLY4. Display the contents of all headers using -x option
Information related to all the headers in the object file can be retrieved using the -x option.
$ objdump -x a.out
a.out: file format elf64-x86-64
a.out
architecture: i386:x86-64, flags 0x00000112:
EXEC_P, HAS_SYMS, D_PAGED
start address 0x0000000000400440
Program Header:
PHDR off 0x0000000000000040 vaddr 0x0000000000400040 paddr 0x0000000000400040 align 2**3
filesz 0x00000000000001f8 memsz 0x00000000000001f8 flags r-x
INTERP off 0x0000000000000238 vaddr 0x0000000000400238 paddr 0x0000000000400238 align 2**0
filesz 0x000000000000001c memsz 0x000000000000001c flags r--
LOAD off 0x0000000000000000 vaddr 0x0000000000400000 paddr 0x0000000000400000 align 2**21
filesz 0x000000000000075c memsz 0x000000000000075c flags r-x
LOAD off 0x0000000000000e10 vaddr 0x0000000000600e10 paddr 0x0000000000600e10 align 2**21
filesz 0x0000000000000230 memsz 0x0000000000000238 flags rw-
DYNAMIC off 0x0000000000000e28 vaddr 0x0000000000600e28 paddr 0x0000000000600e28 align 2**3
filesz 0x00000000000001d0 memsz 0x00000000000001d0 flags rw-
NOTE off 0x0000000000000254 vaddr 0x0000000000400254 paddr 0x0000000000400254 align 2**2
filesz 0x0000000000000044 memsz 0x0000000000000044 flags r--
EH_FRAME off 0x0000000000000650 vaddr 0x0000000000400650 paddr 0x0000000000400650 align 2**2
filesz 0x0000000000000034 memsz 0x0000000000000034 flags r--
STACK off 0x0000000000000000 vaddr 0x0000000000000000 paddr 0x0000000000000000 align 2**3
filesz 0x0000000000000000 memsz 0x0000000000000000 flags rw-
RELRO off 0x0000000000000e10 vaddr 0x0000000000600e10 paddr 0x0000000000600e10 align 2**0
filesz 0x00000000000001f0 memsz 0x00000000000001f0 flags r--
Dynamic Section:
NEEDED libc.so.6
INIT 0x00000000004003e0
FINI 0x0000000000400624
INIT_ARRAY 0x0000000000600e10
INIT_ARRAYSZ 0x0000000000000008
FINI_ARRAY 0x0000000000600e18
FINI_ARRAYSZ 0x0000000000000008
GNU_HASH 0x0000000000400298
STRTAB 0x0000000000400318
SYMTAB 0x00000000004002b8
STRSZ 0x000000000000003f
SYMENT 0x0000000000000018
DEBUG 0x0000000000000000
PLTGOT 0x0000000000601000
PLTRELSZ 0x0000000000000048
PLTREL 0x0000000000000007
JMPREL 0x0000000000400398
RELA 0x0000000000400380
RELASZ 0x0000000000000018
RELAENT 0x0000000000000018
VERNEED 0x0000000000400360
VERNEEDNUM 0x0000000000000001
VERSYM 0x0000000000400358
Version References:
required from libc.so.6:
0x09691a75 0x00 02 GLIBC_2.2.5
Sections:
Idx Name Size VMA LMA File off Algn
0 .interp 0000001c 0000000000400238 0000000000400238 00000238 2**0
CONTENTS, ALLOC, LOAD, READONLY, DATA
1 .note.ABI-tag 00000020 0000000000400254 0000000000400254 00000254 2**2
CONTENTS, ALLOC, LOAD, READONLY, DATA
2 .note.gnu.build-id 00000024 0000000000400274 0000000000400274 00000274 2**2
CONTENTS, ALLOC, LOAD, READONLY, DATA
3 .gnu.hash 0000001c 0000000000400298 0000000000400298 00000298 2**3
CONTENTS, ALLOC, LOAD, READONLY, DATA
4 .dynsym 00000060 00000000004002b8 00000000004002b8 000002b8 2**3
CONTENTS, ALLOC, LOAD, READONLY, DATA
5 .dynstr 0000003f 0000000000400318 0000000000400318 00000318 2**0
CONTENTS, ALLOC, LOAD, READONLY, DATA
6 .gnu.version 00000008 0000000000400358 0000000000400358 00000358 2**1
CONTENTS, ALLOC, LOAD, READONLY, DATA
7 .gnu.version_r 00000020 0000000000400360 0000000000400360 00000360 2**3
CONTENTS, ALLOC, LOAD, READONLY, DATA
8 .rela.dyn 00000018 0000000000400380 0000000000400380 00000380 2**3
CONTENTS, ALLOC, LOAD, READONLY, DATA
9 .rela.plt 00000048 0000000000400398 0000000000400398 00000398 2**3
CONTENTS, ALLOC, LOAD, READONLY, DATA
10 .init 0000001a 00000000004003e0 00000000004003e0 000003e0 2**2
CONTENTS, ALLOC, LOAD, READONLY, CODE
11 .plt 00000040 0000000000400400 0000000000400400 00000400 2**4
CONTENTS, ALLOC, LOAD, READONLY, CODE
12 .text 000001e4 0000000000400440 0000000000400440 00000440 2**4
CONTENTS, ALLOC, LOAD, READONLY, CODE
13 .fini 00000009 0000000000400624 0000000000400624 00000624 2**2
CONTENTS, ALLOC, LOAD, READONLY, CODE
14 .rodata 00000020 0000000000400630 0000000000400630 00000630 2**2
CONTENTS, ALLOC, LOAD, READONLY, DATA
15 .eh_frame_hdr 00000034 0000000000400650 0000000000400650 00000650 2**2
CONTENTS, ALLOC, LOAD, READONLY, DATA
16 .eh_frame 000000d4 0000000000400688 0000000000400688 00000688 2**3
CONTENTS, ALLOC, LOAD, READONLY, DATA
17 .init_array 00000008 0000000000600e10 0000000000600e10 00000e10 2**3
CONTENTS, ALLOC, LOAD, DATA
18 .fini_array 00000008 0000000000600e18 0000000000600e18 00000e18 2**3
CONTENTS, ALLOC, LOAD, DATA
19 .jcr 00000008 0000000000600e20 0000000000600e20 00000e20 2**3
CONTENTS, ALLOC, LOAD, DATA
20 .dynamic 000001d0 0000000000600e28 0000000000600e28 00000e28 2**3
CONTENTS, ALLOC, LOAD, DATA
21 .got 00000008 0000000000600ff8 0000000000600ff8 00000ff8 2**3
CONTENTS, ALLOC, LOAD, DATA
22 .got.plt 00000030 0000000000601000 0000000000601000 00001000 2**3
CONTENTS, ALLOC, LOAD, DATA
23 .data 00000010 0000000000601030 0000000000601030 00001030 2**3
CONTENTS, ALLOC, LOAD, DATA
24 .bss 00000008 0000000000601040 0000000000601040 00001040 2**2
ALLOC
25 .comment 0000002a 0000000000000000 0000000000000000 00001040 2**0
CONTENTS, READONLY
SYMBOL TABLE:
0000000000400238 l d .interp 0000000000000000 .interp
0000000000400254 l d .note.ABI-tag 0000000000000000 .note.ABI-tag
0000000000400274 l d .note.gnu.build-id 0000000000000000 .note.gnu.build-id
0000000000400298 l d .gnu.hash 0000000000000000 .gnu.hash
00000000004002b8 l d .dynsym 0000000000000000 .dynsym
0000000000400318 l d .dynstr 0000000000000000 .dynstr
0000000000400358 l d .gnu.version 0000000000000000 .gnu.version
0000000000400360 l d .gnu.version_r 0000000000000000 .gnu.version_r
0000000000400380 l d .rela.dyn 0000000000000000 .rela.dyn
0000000000400398 l d .rela.plt 0000000000000000 .rela.plt
00000000004003e0 l d .init 0000000000000000 .init
0000000000400400 l d .plt 0000000000000000 .plt
0000000000400440 l d .text 0000000000000000 .text
0000000000400624 l d .fini 0000000000000000 .fini
0000000000400630 l d .rodata 0000000000000000 .rodata
0000000000400650 l d .eh_frame_hdr 0000000000000000 .eh_frame_hdr
0000000000400688 l d .eh_frame 0000000000000000 .eh_frame
0000000000600e10 l d .init_array 0000000000000000 .init_array
0000000000600e18 l d .fini_array 0000000000000000 .fini_array
0000000000600e20 l d .jcr 0000000000000000 .jcr
0000000000600e28 l d .dynamic 0000000000000000 .dynamic
0000000000600ff8 l d .got 0000000000000000 .got
0000000000601000 l d .got.plt 0000000000000000 .got.plt
0000000000601030 l d .data 0000000000000000 .data
0000000000601040 l d .bss 0000000000000000 .bss
0000000000000000 l d .comment 0000000000000000 .comment
0000000000000000 l df *ABS* 0000000000000000 crtstuff.c
0000000000600e20 l O .jcr 0000000000000000 __JCR_LIST__
0000000000400470 l F .text 0000000000000000 deregister_tm_clones
00000000004004a0 l F .text 0000000000000000 register_tm_clones
00000000004004e0 l F .text 0000000000000000 __do_global_dtors_aux
0000000000601040 l O .bss 0000000000000001 completed.6718
0000000000600e18 l O .fini_array 0000000000000000 __do_global_dtors_aux_fini_array_entry
0000000000400500 l F .text 0000000000000000 frame_dummy
0000000000600e10 l O .init_array 0000000000000000 __frame_dummy_init_array_entry
0000000000000000 l df *ABS* 0000000000000000 factorial.c
0000000000000000 l df *ABS* 0000000000000000 crtstuff.c
0000000000400758 l O .eh_frame 0000000000000000 __FRAME_END__
0000000000600e20 l O .jcr 0000000000000000 __JCR_END__
0000000000000000 l df *ABS* 0000000000000000
0000000000600e18 l .init_array 0000000000000000 __init_array_end
0000000000600e28 l O .dynamic 0000000000000000 _DYNAMIC
0000000000600e10 l .init_array 0000000000000000 __init_array_start
0000000000601000 l O .got.plt 0000000000000000 _GLOBAL_OFFSET_TABLE_
0000000000400620 g F .text 0000000000000002 __libc_csu_fini
0000000000000000 w *UND* 0000000000000000 _ITM_deregisterTMCloneTable
0000000000601030 w .data 0000000000000000 data_start
0000000000601040 g .data 0000000000000000 _edata
0000000000400624 g F .fini 0000000000000000 _fini
0000000000000000 F *UND* 0000000000000000 printf@@GLIBC_2.2.5
0000000000000000 F *UND* 0000000000000000 __libc_start_main@@GLIBC_2.2.5
0000000000601030 g .data 0000000000000000 __data_start
0000000000000000 w *UND* 0000000000000000 __gmon_start__
0000000000601038 g O .data 0000000000000000 .hidden __dso_handle
0000000000400630 g O .rodata 0000000000000004 _IO_stdin_used
0000000000400590 g F .text 0000000000000089 __libc_csu_init
0000000000601048 g .bss 0000000000000000 _end
0000000000400440 g F .text 0000000000000000 _start
0000000000601040 g .bss 0000000000000000 __bss_start
000000000040052c g F .text 000000000000005e main
0000000000000000 w *UND* 0000000000000000 _Jv_RegisterClasses
0000000000601040 g O .data 0000000000000000 .hidden __TMC_END__
0000000000000000 w *UND* 0000000000000000 _ITM_registerTMCloneTable
00000000004003e0 g F .init 0000000000000000 _init5. Display assembler contents of executable sections using -d option
$ objdump -d a.out a.out: file format elf64-x86-64 Disassembly of section .init: 00000000004003e0 <_init>: 4003e0: 48 83 ec 08 sub $0x8,%rsp 4003e4: 48 8b 05 0d 0c 20 00 mov 0x200c0d(%rip),%rax # 600ff8 <_DYNAMIC+0x1d0> 4003eb: 48 85 c0 test %rax,%rax 4003ee: 74 05 je 4003f5 <_init+0x15> 4003f0: e8 3b 00 00 00 callq 400430 <__gmon_start__@plt> 4003f5: 48 83 c4 08 add $0x8,%rsp 4003f9: c3 retq Disassembly of section .plt: 0000000000400400 <printf@plt-0x10>: 400400: ff 35 02 0c 20 00 pushq 0x200c02(%rip) # 601008 <_GLOBAL_OFFSET_TABLE_+0x8> 400406: ff 25 04 0c 20 00 jmpq *0x200c04(%rip) # 601010 <_GLOBAL_OFFSET_TABLE_+0x10> 40040c: 0f 1f 40 00 nopl 0x0(%rax) 0000000000400410 <printf@plt>: 400410: ff 25 02 0c 20 00 jmpq *0x200c02(%rip) # 601018 <_GLOBAL_OFFSET_TABLE_+0x18> 400416: 68 00 00 00 00 pushq $0x0 40041b: e9 e0 ff ff ff jmpq 400400 <_init+0x20> 0000000000400420 <__libc_start_main@plt>: 400420: ff 25 fa 0b 20 00 jmpq *0x200bfa(%rip) # 601020 <_GLOBAL_OFFSET_TABLE_+0x20> 400426: 68 01 00 00 00 pushq $0x1 40042b: e9 d0 ff ff ff jmpq 400400 <_init+0x20> 0000000000400430 <__gmon_start__@plt>: 400430: ff 25 f2 0b 20 00 jmpq *0x200bf2(%rip) # 601028 <_GLOBAL_OFFSET_TABLE_+0x28> 400436: 68 02 00 00 00 pushq $0x2 40043b: e9 c0 ff ff ff jmpq 400400 <_init+0x20> Disassembly of section .text: 0000000000400440 <_start>: 400440: 31 ed xor %ebp,%ebp 400442: 49 89 d1 mov %rdx,%r9 400445: 5e pop %rsi 400446: 48 89 e2 mov %rsp,%rdx 400449: 48 83 e4 f0 and $0xfffffffffffffff0,%rsp 40044d: 50 push %rax 40044e: 54 push %rsp 40044f: 49 c7 c0 20 06 40 00 mov $0x400620,%r8 400456: 48 c7 c1 90 05 40 00 mov $0x400590,%rcx 40045d: 48 c7 c7 2c 05 40 00 mov $0x40052c,%rdi 400464: e8 b7 ff ff ff callq 400420 <__libc_start_main@plt> 400469: f4 hlt 40046a: 66 90 xchg %ax,%ax 40046c: 0f 1f 40 00 nopl 0x0(%rax) 0000000000400470 <deregister_tm_clones>: 400470: b8 47 10 60 00 mov $0x601047,%eax 400475: 55 push %rbp 400476: 48 2d 40 10 60 00 sub $0x601040,%rax 40047c: 48 83 f8 0e cmp $0xe,%rax 400480: 48 89 e5 mov %rsp,%rbp 400483: 77 02 ja 400487 <deregister_tm_clones+0x17> 400485: 5d pop %rbp 400486: c3 retq 400487: b8 00 00 00 00 mov $0x0,%eax 40048c: 48 85 c0 test %rax,%rax 40048f: 74 f4 je 400485 <deregister_tm_clones+0x15> 400491: 5d pop %rbp 400492: bf 40 10 60 00 mov $0x601040,%edi 400497: ff e0 jmpq *%rax 400499: 0f 1f 80 00 00 00 00 nopl 0x0(%rax) 00000000004004a0 <register_tm_clones>: 4004a0: b8 40 10 60 00 mov $0x601040,%eax 4004a5: 55 push %rbp 4004a6: 48 2d 40 10 60 00 sub $0x601040,%rax 4004ac: 48 c1 f8 03 sar $0x3,%rax 4004b0: 48 89 e5 mov %rsp,%rbp 4004b3: 48 89 c2 mov %rax,%rdx 4004b6: 48 c1 ea 3f shr $0x3f,%rdx 4004ba: 48 01 d0 add %rdx,%rax 4004bd: 48 89 c6 mov %rax,%rsi 4004c0: 48 d1 fe sar %rsi 4004c3: 75 02 jne 4004c7 <register_tm_clones+0x27> 4004c5: 5d pop %rbp 4004c6: c3 retq 4004c7: ba 00 00 00 00 mov $0x0,%edx 4004cc: 48 85 d2 test %rdx,%rdx 4004cf: 74 f4 je 4004c5 <register_tm_clones+0x25> 4004d1: 5d pop %rbp 4004d2: bf 40 10 60 00 mov $0x601040,%edi 4004d7: ff e2 jmpq *%rdx 4004d9: 0f 1f 80 00 00 00 00 nopl 0x0(%rax) 00000000004004e0 <__do_global_dtors_aux>: 4004e0: 80 3d 59 0b 20 00 00 cmpb $0x0,0x200b59(%rip) # 601040 <__TMC_END__> 4004e7: 75 11 jne 4004fa <__do_global_dtors_aux+0x1a> 4004e9: 55 push %rbp 4004ea: 48 89 e5 mov %rsp,%rbp 4004ed: e8 7e ff ff ff callq 400470 <deregister_tm_clones> 4004f2: 5d pop %rbp 4004f3: c6 05 46 0b 20 00 01 movb $0x1,0x200b46(%rip) # 601040 <__TMC_END__> 4004fa: f3 c3 repz retq 4004fc: 0f 1f 40 00 nopl 0x0(%rax) 0000000000400500 <frame_dummy>: 400500: 48 83 3d 18 09 20 00 cmpq $0x0,0x200918(%rip) # 600e20 <__JCR_END__> 400507: 00 400508: 74 1b je 400525 <frame_dummy+0x25> 40050a: b8 00 00 00 00 mov $0x0,%eax 40050f: 48 85 c0 test %rax,%rax 400512: 74 11 je 400525 <frame_dummy+0x25> 400514: 55 push %rbp 400515: bf 20 0e 60 00 mov $0x600e20,%edi 40051a: 48 89 e5 mov %rsp,%rbp 40051d: ff d0 callq *%rax 40051f: 5d pop %rbp 400520: e9 7b ff ff ff jmpq 4004a0 <register_tm_clones> 400525: e9 76 ff ff ff jmpq 4004a0 <register_tm_clones> 40052a: 66 90 xchg %ax,%ax 000000000040052c <main>: 40052c: 55 push %rbp 40052d: 48 89 e5 mov %rsp,%rbp 400530: 48 83 ec 10 sub $0x10,%rsp 400534: c7 45 fc 06 00 00 00 movl $0x6,-0x4(%rbp) 40053b: 8b 05 0b 01 00 00 mov 0x10b(%rip),%eax # 40064c <_IO_stdin_used+0x1c> 400541: 89 45 f4 mov %eax,-0xc(%rbp) 400544: c7 45 f8 01 00 00 00 movl $0x1,-0x8(%rbp) 40054b: eb 17 jmp 400564 <main+0x38> 40054d: f3 0f 2a 45 f8 cvtsi2ssl -0x8(%rbp),%xmm0 400552: f3 0f 10 4d f4 movss -0xc(%rbp),%xmm1 400557: f3 0f 59 c1 mulss %xmm1,%xmm0 40055b: f3 0f 11 45 f4 movss %xmm0,-0xc(%rbp) 400560: 83 45 f8 01 addl $0x1,-0x8(%rbp) 400564: 8b 45 f8 mov -0x8(%rbp),%eax 400567: 3b 45 fc cmp -0x4(%rbp),%eax 40056a: 7e e1 jle 40054d <main+0x21> 40056c: f3 0f 10 45 f4 movss -0xc(%rbp),%xmm0 400571: 0f 5a c0 cvtps2pd %xmm0,%xmm0 400574: bf 34 06 40 00 mov $0x400634,%edi 400579: b8 01 00 00 00 mov $0x1,%eax 40057e: e8 8d fe ff ff callq 400410 <printf@plt> 400583: b8 00 00 00 00 mov $0x0,%eax 400588: c9 leaveq 400589: c3 retq 40058a: 66 0f 1f 44 00 00 nopw 0x0(%rax,%rax,1) 0000000000400590 <__libc_csu_init>: 400590: 48 89 6c 24 d8 mov %rbp,-0x28(%rsp) 400595: 4c 89 64 24 e0 mov %r12,-0x20(%rsp) 40059a: 48 8d 2d 77 08 20 00 lea 0x200877(%rip),%rbp # 600e18 <__init_array_end> 4005a1: 4c 8d 25 68 08 20 00 lea 0x200868(%rip),%r12 # 600e10 <__frame_dummy_init_array_entry> 4005a8: 48 89 5c 24 d0 mov %rbx,-0x30(%rsp) 4005ad: 4c 89 6c 24 e8 mov %r13,-0x18(%rsp) 4005b2: 4c 89 74 24 f0 mov %r14,-0x10(%rsp) 4005b7: 4c 89 7c 24 f8 mov %r15,-0x8(%rsp) 4005bc: 48 83 ec 38 sub $0x38,%rsp 4005c0: 4c 29 e5 sub %r12,%rbp 4005c3: 41 89 ff mov %edi,%r15d 4005c6: 49 89 f6 mov %rsi,%r14 4005c9: 48 c1 fd 03 sar $0x3,%rbp 4005cd: 49 89 d5 mov %rdx,%r13 4005d0: 31 db xor %ebx,%ebx 4005d2: e8 09 fe ff ff callq 4003e0 <_init> 4005d7: 48 85 ed test %rbp,%rbp 4005da: 74 1a je 4005f6 <__libc_csu_init+0x66> 4005dc: 0f 1f 40 00 nopl 0x0(%rax) 4005e0: 4c 89 ea mov %r13,%rdx 4005e3: 4c 89 f6 mov %r14,%rsi 4005e6: 44 89 ff mov %r15d,%edi 4005e9: 41 ff 14 dc callq *(%r12,%rbx,8) 4005ed: 48 83 c3 01 add $0x1,%rbx 4005f1: 48 39 eb cmp %rbp,%rbx 4005f4: 75 ea jne 4005e0 <__libc_csu_init+0x50> 4005f6: 48 8b 5c 24 08 mov 0x8(%rsp),%rbx 4005fb: 48 8b 6c 24 10 mov 0x10(%rsp),%rbp 400600: 4c 8b 64 24 18 mov 0x18(%rsp),%r12 400605: 4c 8b 6c 24 20 mov 0x20(%rsp),%r13 40060a: 4c 8b 74 24 28 mov 0x28(%rsp),%r14 40060f: 4c 8b 7c 24 30 mov 0x30(%rsp),%r15 400614: 48 83 c4 38 add $0x38,%rsp 400618: c3 retq 400619: 0f 1f 80 00 00 00 00 nopl 0x0(%rax) 0000000000400620 <__libc_csu_fini>: 400620: f3 c3 repz retq 400622: 66 90 xchg %ax,%ax Disassembly of section .fini: 0000000000400624 <_fini>: 400624: 48 83 ec 08 sub $0x8,%rsp 400628: 48 83 c4 08 add $0x8,%rsp 40062c: c3 retq
6. Display assembler contents of all sections using -D option
In case the assembler contents of all the sections is required in output, the option -D can be used.
a.out: file format elf64-x86-64
Disassembly of section .interp:
0000000000400238 <.interp>:
400238: 2f (bad)
400239: 6c insb (%dx),%es:(%rdi)
40023a: 69 62 36 34 2f 6c 64 imul $0x646c2f34,0x36(%rdx),%esp
400241: 2d 6c 69 6e 75 sub $0x756e696c,%eax
400246: 78 2d js 400275 <_init-0x16b>
400248: 78 38 js 400282 <_init-0x15e>
40024a: 36 ss
40024b: 2d 36 34 2e 73 sub $0x732e3436,%eax
400250: 6f outsl %ds:(%rsi),(%dx)
400251: 2e 32 00 xor %cs:(%rax),%al
Disassembly of section .note.ABI-tag:
0000000000400254 <.note.ABI-tag>:
400254: 04 00 add $0x0,%al
400256: 00 00 add %al,(%rax)
400258: 10 00 adc %al,(%rax)
40025a: 00 00 add %al,(%rax)
40025c: 01 00 add %eax,(%rax)
40025e: 00 00 add %al,(%rax)
400260: 47 rex.RXB
400261: 4e 55 rex.WRX push %rbp
400263: 00 00 add %al,(%rax)
400265: 00 00 add %al,(%rax)
400267: 00 02 add %al,(%rdx)
400269: 00 00 add %al,(%rax)
40026b: 00 06 add %al,(%rsi)
40026d: 00 00 add %al,(%rax)
40026f: 00 18 add %bl,(%rax)
400271: 00 00 add %al,(%rax)
...
Disassembly of section .note.gnu.build-id:
0000000000400274 <.note.gnu.build-id>:
400274: 04 00 add $0x0,%al
400276: 00 00 add %al,(%rax)
400278: 14 00 adc $0x0,%al
40027a: 00 00 add %al,(%rax)
40027c: 03 00 add (%rax),%eax
40027e: 00 00 add %al,(%rax)
400280: 47 rex.RXB
400281: 4e 55 rex.WRX push %rbp
400283: 00 cc add %cl,%ah
400285: 55 push %rbp
400286: ad lods %ds:(%rsi),%eax
400287: 32 30 xor (%rax),%dh
400289: ea (bad)
40028a: a5 movsl %ds:(%rsi),%es:(%rdi)
40028b: b6 89 mov $0x89,%dh
40028d: f4 hlt
40028e: 43 2c c0 rex.XB sub $0xc0,%al
400291: 74 27 je 4002ba <_init-0x126>
400293: 4d a8 ec rex.WRB test $0xec,%al
400296: 6f outsl %ds:(%rsi),(%dx)
400297: 34 .byte 0x34
Disassembly of section .gnu.hash:
0000000000400298 <.gnu.hash>:
400298: 01 00 add %eax,(%rax)
40029a: 00 00 add %al,(%rax)
.....7. Display the full contents of all sections using -s option
$ objdump -s a.out a.out: file format elf64-x86-64 Contents of section .interp: 400238 2f6c6962 36342f6c 642d6c69 6e75782d /lib64/ld-linux- 400248 7838362d 36342e73 6f2e3200 x86-64.so.2. Contents of section .note.ABI-tag: 400254 04000000 10000000 01000000 474e5500 ............GNU. 400264 00000000 02000000 06000000 18000000 ................ Contents of section .note.gnu.build-id: 400274 04000000 14000000 03000000 474e5500 ............GNU. 400284 cc55ad32 30eaa5b6 89f4432c c074274d .U.20.....C,.t'M 400294 a8ec6f34 ..o4 Contents of section .gnu.hash: 400298 01000000 01000000 01000000 00000000 ................ 4002a8 00000000 00000000 00000000 ............ Contents of section .dynsym: 4002b8 00000000 00000000 00000000 00000000 ................ 4002c8 00000000 00000000 0b000000 12000000 ................ 4002d8 00000000 00000000 00000000 00000000 ................ 4002e8 12000000 12000000 00000000 00000000 ................ 4002f8 00000000 00000000 24000000 20000000 ........$... ... 400308 00000000 00000000 00000000 00000000 ................ Contents of section .dynstr: 400318 006c6962 632e736f 2e360070 72696e74 .libc.so.6.print 400328 66005f5f 6c696263 5f737461 72745f6d f.__libc_start_m 400338 61696e00 5f5f676d 6f6e5f73 74617274 ain.__gmon_start 400348 5f5f0047 4c494243 5f322e32 2e3500 __.GLIBC_2.2.5. Contents of section .gnu.version: 400358 00000200 02000000 ........ Contents of section .gnu.version_r: 400360 01000100 01000000 10000000 00000000 ................ 400370 751a6909 00000200 33000000 00000000 u.i.....3....... Contents of section .rela.dyn: 400380 f80f6000 00000000 06000000 03000000 ..`............. 400390 00000000 00000000 ........ Contents of section .rela.plt: 400398 18106000 00000000 07000000 01000000 ..`............. 4003a8 00000000 00000000 20106000 00000000 ........ .`..... 4003b8 07000000 02000000 00000000 00000000 ................ 4003c8 28106000 00000000 07000000 03000000 (.`............. 4003d8 00000000 00000000 ........ Contents of section .init: 4003e0 4883ec08 488b050d 0c200048 85c07405 H...H.... .H..t. 4003f0 e83b0000 004883c4 08c3 .;...H.... Contents of section .plt: 400400 ff35020c 2000ff25 040c2000 0f1f4000 .5.. ..%.. ...@. 400410 ff25020c 20006800 000000e9 e0ffffff .%.. .h......... 400420 ff25fa0b 20006801 000000e9 d0ffffff .%.. .h......... 400430 ff25f20b 20006802 000000e9 c0ffffff .%.. .h......... Contents of section .text: 400440 31ed4989 d15e4889 e24883e4 f0505449 1.I..^H..H...PTI 400450 c7c02006 400048c7 c1900540 0048c7c7 .. [email protected][email protected].. 400460 2c054000 e8b7ffff fff46690 0f1f4000 ,[email protected]...@. 400470 b8471060 0055482d 40106000 4883f80e .G.`.UH-@.`.H... 400480 4889e577 025dc3b8 00000000 4885c074 H..w.]......H..t 400490 f45dbf40 106000ff e00f1f80 00000000 .].@.`.......... 4004a0 b8401060 0055482d 40106000 48c1f803 .@.`.UH-@.`.H... 4004b0 4889e548 89c248c1 ea3f4801 d04889c6 H..H..H..?H..H.. 4004c0 48d1fe75 025dc3ba 00000000 4885d274 H..u.]......H..t 4004d0 f45dbf40 106000ff e20f1f80 00000000 .].@.`.......... 4004e0 803d590b 20000075 11554889 e5e87eff .=Y. ..u.UH...~. 4004f0 ffff5dc6 05460b20 0001f3c3 0f1f4000 ..]..F. ......@. 400500 48833d18 09200000 741bb800 00000048 H.=.. ..t......H 400510 85c07411 55bf200e 60004889 e5ffd05d ..t.U. .`.H....] 400520 e97bffff ffe976ff ffff6690 554889e5 .{....v...f.UH.. 400530 4883ec10 c745fc06 0000008b 050b0100 H....E.......... 400540 008945f4 c745f801 000000eb 17f30f2a ..E..E.........* 400550 45f8f30f 104df4f3 0f59c1f3 0f1145f4 E....M...Y....E. 400560 8345f801 8b45f83b 45fc7ee1 f30f1045 .E...E.;E.~....E 400570 f40f5ac0 bf340640 00b80100 0000e88d ..Z..4.@........ 400580 feffffb8 00000000 c9c3660f 1f440000 ..........f..D.. 400590 48896c24 d84c8964 24e0488d 2d770820 H.l$.L.d$.H.-w. 4005a0 004c8d25 68082000 48895c24 d04c896c .L.%h. .H.\$.L.l 4005b0 24e84c89 7424f04c 897c24f8 4883ec38 $.L.t$.L.|$.H..8 4005c0 4c29e541 89ff4989 f648c1fd 034989d5 L).A..I..H...I.. 4005d0 31dbe809 feffff48 85ed741a 0f1f4000 1......H..t...@. 4005e0 4c89ea4c 89f64489 ff41ff14 dc4883c3 L..L..D..A...H.. 4005f0 014839eb 75ea488b 5c240848 8b6c2410 .H9.u.H.\$.H.l$. 400600 4c8b6424 184c8b6c 24204c8b 7424284c L.d$.L.l$ L.t$(L 400610 8b7c2430 4883c438 c30f1f80 00000000 .|$0H..8........ 400620 f3c36690 ..f. Contents of section .fini: 400624 4883ec08 4883c408 c3 H...H.... Contents of section .rodata: 400630 01000200 0a204661 63746f72 69616c20 ..... Factorial 400640 6973203a 205b2566 5d0a0000 0000803f is : [%f]......? Contents of section .eh_frame_hdr: 400650 011b033b 34000000 05000000 b0fdffff ...;4........... 400660 80000000 f0fdffff 50000000 dcfeffff ........P....... 400670 a8000000 40ffffff c8000000 d0ffffff ....@........... 400680 f0000000 .... Contents of section .eh_frame: 400688 14000000 00000000 017a5200 01781001 .........zR..x.. 400698 1b0c0708 90010710 14000000 1c000000 ................ 4006a8 98fdffff 2a000000 00000000 00000000 ....*........... 4006b8 14000000 00000000 017a5200 01781001 .........zR..x.. 4006c8 1b0c0708 90010000 24000000 1c000000 ........$....... 4006d8 28fdffff 40000000 000e1046 0e184a0f ([email protected]. 4006e8 0b770880 003f1a3b 2a332422 00000000 .w...?.;*3$".... 4006f8 1c000000 44000000 2cfeffff 5e000000 ....D...,...^... 400708 00410e10 8602430d 0602590c 07080000 .A....C...Y..... 400718 24000000 64000000 70feffff 89000000 $...d...p....... 400728 004a8606 8c05660e 4083078d 048e038f .J....f.@....... 400738 0202580e 08000000 14000000 8c000000 ..X............. 400748 d8feffff 02000000 00000000 00000000 ................ 400758 00000000 .... Contents of section .init_array: 600e10 00054000 00000000 ..@..... Contents of section .fini_array: 600e18 e0044000 00000000 ..@..... Contents of section .jcr: 600e20 00000000 00000000 ........ Contents of section .dynamic: 600e28 01000000 00000000 01000000 00000000 ................ 600e38 0c000000 00000000 e0034000 00000000 ..........@..... 600e48 0d000000 00000000 24064000 00000000 ........$.@..... 600e58 19000000 00000000 100e6000 00000000 ..........`..... 600e68 1b000000 00000000 08000000 00000000 ................ 600e78 1a000000 00000000 180e6000 00000000 ..........`..... 600e88 1c000000 00000000 08000000 00000000 ................ 600e98 f5feff6f 00000000 98024000 00000000 ...o......@..... 600ea8 05000000 00000000 18034000 00000000 ..........@..... 600eb8 06000000 00000000 b8024000 00000000 ..........@..... 600ec8 0a000000 00000000 3f000000 00000000 ........?....... 600ed8 0b000000 00000000 18000000 00000000 ................ 600ee8 15000000 00000000 00000000 00000000 ................ 600ef8 03000000 00000000 00106000 00000000 ..........`..... 600f08 02000000 00000000 48000000 00000000 ........H....... 600f18 14000000 00000000 07000000 00000000 ................ 600f28 17000000 00000000 98034000 00000000 ..........@..... 600f38 07000000 00000000 80034000 00000000 ..........@..... 600f48 08000000 00000000 18000000 00000000 ................ 600f58 09000000 00000000 18000000 00000000 ................ 600f68 feffff6f 00000000 60034000 00000000 ...o....`.@..... 600f78 ffffff6f 00000000 01000000 00000000 ...o............ 600f88 f0ffff6f 00000000 58034000 00000000 ...o....X.@..... 600f98 00000000 00000000 00000000 00000000 ................ 600fa8 00000000 00000000 00000000 00000000 ................ 600fb8 00000000 00000000 00000000 00000000 ................ 600fc8 00000000 00000000 00000000 00000000 ................ 600fd8 00000000 00000000 00000000 00000000 ................ 600fe8 00000000 00000000 00000000 00000000 ................ Contents of section .got: 600ff8 00000000 00000000 ........ Contents of section .got.plt: 601000 280e6000 00000000 00000000 00000000 (.`............. 601010 00000000 00000000 16044000 00000000 ..........@..... 601020 26044000 00000000 36044000 00000000 &[email protected].@..... Contents of section .data: 601030 00000000 00000000 00000000 00000000 ................ Contents of section .comment: 0000 4743433a 20285562 756e7475 2f4c696e GCC: (Ubuntu/Lin 0010 61726f20 342e372e 332d3175 62756e74 aro 4.7.3-1ubunt 0020 75312920 342e372e 3300 u1) 4.7.3.
8. Display debug information using -g option
$ objdump -g a.out a.out: file format elf64-x86-64 Contents of the .eh_frame section: 00000000 00000014 00000000 CIE Version: 1 Augmentation: "zR" Code alignment factor: 1 Data alignment factor: -8 Return address column: 16 Augmentation data: 1b DW_CFA_def_cfa: r7 (rsp) ofs 8 DW_CFA_offset: r16 (rip) at cfa-8 DW_CFA_undefined: r16 (rip) 00000018 00000014 0000001c FDE cie=00000000 pc=fffffffffffffdb8..fffffffffffffde2 DW_CFA_nop DW_CFA_nop DW_CFA_nop DW_CFA_nop DW_CFA_nop DW_CFA_nop DW_CFA_nop 00000030 00000014 00000000 CIE Version: 1 Augmentation: "zR" Code alignment factor: 1 Data alignment factor: -8 Return address column: 16 Augmentation data: 1b DW_CFA_def_cfa: r7 (rsp) ofs 8 DW_CFA_offset: r16 (rip) at cfa-8 DW_CFA_nop DW_CFA_nop 00000048 00000024 0000001c FDE cie=00000030 pc=fffffffffffffd78..fffffffffffffdb8 DW_CFA_def_cfa_offset: 16 DW_CFA_advance_loc: 6 to fffffffffffffd7e DW_CFA_def_cfa_offset: 24 DW_CFA_advance_loc: 10 to fffffffffffffd88 DW_CFA_def_cfa_expression (DW_OP_breg7 (rsp): 8; DW_OP_breg16 (rip): 0; DW_OP_lit15; DW_OP_and; DW_OP_lit11; DW_OP_ge; DW_OP_lit3; DW_OP_shl; DW_OP_plus) DW_CFA_nop DW_CFA_nop DW_CFA_nop DW_CFA_nop 00000070 0000001c 00000044 FDE cie=00000030 pc=fffffffffffffea4..ffffffffffffff02 DW_CFA_advance_loc: 1 to fffffffffffffea5 DW_CFA_def_cfa_offset: 16 DW_CFA_offset: r6 (rbp) at cfa-16 DW_CFA_advance_loc: 3 to fffffffffffffea8 DW_CFA_def_cfa_register: r6 (rbp) DW_CFA_advance_loc1: 89 to ffffffffffffff01 DW_CFA_def_cfa: r7 (rsp) ofs 8 DW_CFA_nop DW_CFA_nop 00000090 00000024 00000064 FDE cie=00000030 pc=ffffffffffffff08..ffffffffffffff91 DW_CFA_advance_loc: 10 to ffffffffffffff12 DW_CFA_offset: r6 (rbp) at cfa-48 DW_CFA_offset: r12 (r12) at cfa-40 DW_CFA_advance_loc: 38 to ffffffffffffff38 DW_CFA_def_cfa_offset: 64 DW_CFA_offset: r3 (rbx) at cfa-56 DW_CFA_offset: r13 (r13) at cfa-32 DW_CFA_offset: r14 (r14) at cfa-24 DW_CFA_offset: r15 (r15) at cfa-16 DW_CFA_advance_loc1: 88 to ffffffffffffff90 DW_CFA_def_cfa_offset: 8 DW_CFA_nop DW_CFA_nop DW_CFA_nop 000000b8 00000014 0000008c FDE cie=00000030 pc=ffffffffffffff98..ffffffffffffff9a DW_CFA_nop DW_CFA_nop DW_CFA_nop DW_CFA_nop DW_CFA_nop DW_CFA_nop DW_CFA_nop 000000d0 ZERO terminator
9. Display the contents of symbol table (or tables) using the -t option
$ objdump -t a.out a.out: file format elf64-x86-64 SYMBOL TABLE: 0000000000400238 l d .interp 0000000000000000 .interp 0000000000400254 l d .note.ABI-tag 0000000000000000 .note.ABI-tag 0000000000400274 l d .note.gnu.build-id 0000000000000000 .note.gnu.build-id 0000000000400298 l d .gnu.hash 0000000000000000 .gnu.hash 00000000004002b8 l d .dynsym 0000000000000000 .dynsym 0000000000400318 l d .dynstr 0000000000000000 .dynstr 0000000000400358 l d .gnu.version 0000000000000000 .gnu.version 0000000000400360 l d .gnu.version_r 0000000000000000 .gnu.version_r 0000000000400380 l d .rela.dyn 0000000000000000 .rela.dyn 0000000000400398 l d .rela.plt 0000000000000000 .rela.plt 00000000004003e0 l d .init 0000000000000000 .init 0000000000400400 l d .plt 0000000000000000 .plt 0000000000400440 l d .text 0000000000000000 .text 0000000000400624 l d .fini 0000000000000000 .fini 0000000000400630 l d .rodata 0000000000000000 .rodata 0000000000400650 l d .eh_frame_hdr 0000000000000000 .eh_frame_hdr 0000000000400688 l d .eh_frame 0000000000000000 .eh_frame 0000000000600e10 l d .init_array 0000000000000000 .init_array 0000000000600e18 l d .fini_array 0000000000000000 .fini_array 0000000000600e20 l d .jcr 0000000000000000 .jcr 0000000000600e28 l d .dynamic 0000000000000000 .dynamic 0000000000600ff8 l d .got 0000000000000000 .got 0000000000601000 l d .got.plt 0000000000000000 .got.plt 0000000000601030 l d .data 0000000000000000 .data 0000000000601040 l d .bss 0000000000000000 .bss 0000000000000000 l d .comment 0000000000000000 .comment 0000000000000000 l df *ABS* 0000000000000000 crtstuff.c 0000000000600e20 l O .jcr 0000000000000000 __JCR_LIST__ 0000000000400470 l F .text 0000000000000000 deregister_tm_clones 00000000004004a0 l F .text 0000000000000000 register_tm_clones 00000000004004e0 l F .text 0000000000000000 __do_global_dtors_aux 0000000000601040 l O .bss 0000000000000001 completed.6718 0000000000600e18 l O .fini_array 0000000000000000 __do_global_dtors_aux_fini_array_entry 0000000000400500 l F .text 0000000000000000 frame_dummy 0000000000600e10 l O .init_array 0000000000000000 __frame_dummy_init_array_entry 0000000000000000 l df *ABS* 0000000000000000 factorial.c 0000000000000000 l df *ABS* 0000000000000000 crtstuff.c 0000000000400758 l O .eh_frame 0000000000000000 __FRAME_END__ 0000000000600e20 l O .jcr 0000000000000000 __JCR_END__ 0000000000000000 l df *ABS* 0000000000000000 0000000000600e18 l .init_array 0000000000000000 __init_array_end 0000000000600e28 l O .dynamic 0000000000000000 _DYNAMIC 0000000000600e10 l .init_array 0000000000000000 __init_array_start 0000000000601000 l O .got.plt 0000000000000000 _GLOBAL_OFFSET_TABLE_ 0000000000400620 g F .text 0000000000000002 __libc_csu_fini 0000000000000000 w *UND* 0000000000000000 _ITM_deregisterTMCloneTable 0000000000601030 w .data 0000000000000000 data_start 0000000000601040 g .data 0000000000000000 _edata 0000000000400624 g F .fini 0000000000000000 _fini 0000000000000000 F *UND* 0000000000000000 printf@@GLIBC_2.2.5 0000000000000000 F *UND* 0000000000000000 __libc_start_main@@GLIBC_2.2.5 0000000000601030 g .data 0000000000000000 __data_start 0000000000000000 w *UND* 0000000000000000 __gmon_start__ 0000000000601038 g O .data 0000000000000000 .hidden __dso_handle 0000000000400630 g O .rodata 0000000000000004 _IO_stdin_used 0000000000400590 g F .text 0000000000000089 __libc_csu_init 0000000000601048 g .bss 0000000000000000 _end 0000000000400440 g F .text 0000000000000000 _start 0000000000601040 g .bss 0000000000000000 __bss_start 000000000040052c g F .text 000000000000005e main 0000000000000000 w *UND* 0000000000000000 _Jv_RegisterClasses 0000000000601040 g O .data 0000000000000000 .hidden __TMC_END__ 0000000000000000 w *UND* 0000000000000000 _ITM_registerTMCloneTable 00000000004003e0 g F .init 0000000000000000 _init
10. Display the contents of dynamic symbol table using -T option
$ objdump -T a.out a.out: file format elf64-x86-64 DYNAMIC SYMBOL TABLE: 0000000000000000 DF *UND* 0000000000000000 GLIBC_2.2.5 printf 0000000000000000 DF *UND* 0000000000000000 GLIBC_2.2.5 __libc_start_main 0000000000000000 w D *UND* 0000000000000000 __gmon_start__
11. Display the dynamic relocation entries in the file using -R option
$ objdump -R a.out a.out: file format elf64-x86-64 DYNAMIC RELOCATION RECORDS OFFSET TYPE VALUE 0000000000600ff8 R_X86_64_GLOB_DAT __gmon_start__ 0000000000601018 R_X86_64_JUMP_SLOT printf 0000000000601020 R_X86_64_JUMP_SLOT __libc_start_main 0000000000601028 R_X86_64_JUMP_SLOT __gmon_start__
12. Display section of interest using -j option
$ objdump -s -j .rodata a.out a.out: file format elf64-x86-64 Contents of section .rodata: 400630 01000200 0a204661 63746f72 69616c20 ..... Factorial 400640 6973203a 205b2566 5d0a0000 0000803f is : [%f]......?
13. Accept input options from a file using @ option
$ cat options.txt -v -i
Execute the objdump by calling the options.txt file as shown below. This displays the same output as above, as it is reading the options from the options.txt file.
$ objdump @options.txt GNU objdump (GNU Binutils for Ubuntu) 2.20.1-system.20100303 Copyright 2009 Free Software Foundation, Inc. This program is free software; you may redistribute it under the terms of the GNU General Public License version 3 or (at your option) any later version. This program has absolutely no warranty.
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