objdump 简单使用
作者：SkyFire
- 2021 年 12 月 29 日
本文字数：13487 字
阅读完需：约 44 分钟
objdump 是一个在 linux 下用于分析 ELF 文件的工具，现在列一下常用的功能。
直接输入 objdump 输出帮助信息：
用法：objdump <选项> <文件> 显示来自目标 <文件> 的信息。 至少必须给出以下选项之一： -a, --archive-headers Display archive header information -f, --file-headers Display the contents of the overall file header -p, --private-headers Display object format specific file header contents -P, --private=OPT,OPT... Display object format specific contents -h, --[section-]headers Display the contents of the section headers -x, --all-headers Display the contents of all headers -d, --disassemble Display assembler contents of executable sections -D, --disassemble-all Display assembler contents of all sections --disassemble=<sym> Display assembler contents from <sym> -S, --source Intermix source code with disassembly -s, --full-contents Display the full contents of all sections requested -g, --debugging Display debug information in object file -e, --debugging-tags Display debug information using ctags style -G, --stabs Display (in raw form) any STABS info in the file -W[lLiaprmfFsoRtUuTgAckK] or --dwarf[=rawline,=decodedline,=info,=abbrev,=pubnames,=aranges,=macro,=frames, =frames-interp,=str,=loc,=Ranges,=pubtypes, =gdb_index,=trace_info,=trace_abbrev,=trace_aranges, =addr,=cu_index,=links,=follow-links] Display DWARF info in the file -t, --syms Display the contents of the symbol table(s) -T, --dynamic-syms Display the contents of the dynamic symbol table -r, --reloc Display the relocation entries in the file -R, --dynamic-reloc Display the dynamic relocation entries in the file @<file> Read options from <file> -v, --version Display this program's version number -i, --info List object formats and architectures supported -H, --help Display this information
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接下来会使用一个简单的函数作为分析内容：
main.c:
#include <stdio.h>
int add(int a, int b){ return a + b;}
int main(int argc, char** argv){ printf("hello world %d\n", add(5, 6)); return 0;}
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使用 gcc 编译：
gcc -Og -o main main.c
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打印头部信息
objdump -a main
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输出：
main： 文件格式 elf64-x86-64main
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打印文件头
objdump -f main
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输出：
main： 文件格式 elf64-x86-64体系结构：i386:x86-64，标志 0x00000150：HAS_SYMS, DYNAMIC, D_PAGED起始地址 0x0000000000001040
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打印反汇编
objdump -S main
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输出
main： 文件格式 elf64-x86-64
Disassembly of section .init:
0000000000001000 <_init>: 1000: f3 0f 1e fa endbr64 1004: 48 83 ec 08 sub $0x8,%rsp 1008: 48 8b 05 d9 2f 00 00 mov 0x2fd9(%rip),%rax # 3fe8 <__gmon_start__> 100f: 48 85 c0 test %rax,%rax 1012: 74 02 je 1016 <_init+0x16> 1014: ff d0 callq *%rax 1016: 48 83 c4 08 add $0x8,%rsp 101a: c3 retq
Disassembly of section .plt:
0000000000001020 <.plt>: 1020: ff 35 e2 2f 00 00 pushq 0x2fe2(%rip) # 4008 <_GLOBAL_OFFSET_TABLE_+0x8> 1026: ff 25 e4 2f 00 00 jmpq *0x2fe4(%rip) # 4010 <_GLOBAL_OFFSET_TABLE_+0x10> 102c: 0f 1f 40 00 nopl 0x0(%rax)
0000000000001030 <printf@plt>: 1030: ff 25 e2 2f 00 00 jmpq *0x2fe2(%rip) # 4018 <printf@GLIBC_2.2.5> 1036: 68 00 00 00 00 pushq $0x0 103b: e9 e0 ff ff ff jmpq 1020 <.plt>
Disassembly of section .text:
0000000000001040 <_start>: 1040: f3 0f 1e fa endbr64 1044: 31 ed xor %ebp,%ebp 1046: 49 89 d1 mov %rdx,%r9 1049: 5e pop %rsi 104a: 48 89 e2 mov %rsp,%rdx 104d: 48 83 e4 f0 and $0xfffffffffffffff0,%rsp 1051: 50 push %rax 1052: 54 push %rsp 1053: 4c 8d 05 86 01 00 00 lea 0x186(%rip),%r8 # 11e0 <__libc_csu_fini> 105a: 48 8d 0d 0f 01 00 00 lea 0x10f(%rip),%rcx # 1170 <__libc_csu_init> 1061: 48 8d 3d d5 00 00 00 lea 0xd5(%rip),%rdi # 113d <main> 1068: ff 15 72 2f 00 00 callq *0x2f72(%rip) # 3fe0 <__libc_start_main@GLIBC_2.2.5> 106e: f4 hlt 106f: 90 nop
0000000000001070 <deregister_tm_clones>: 1070: 48 8d 3d b9 2f 00 00 lea 0x2fb9(%rip),%rdi # 4030 <__TMC_END__> 1077: 48 8d 05 b2 2f 00 00 lea 0x2fb2(%rip),%rax # 4030 <__TMC_END__> 107e: 48 39 f8 cmp %rdi,%rax 1081: 74 15 je 1098 <deregister_tm_clones+0x28> 1083: 48 8b 05 4e 2f 00 00 mov 0x2f4e(%rip),%rax # 3fd8 <_ITM_deregisterTMCloneTable> 108a: 48 85 c0 test %rax,%rax 108d: 74 09 je 1098 <deregister_tm_clones+0x28> 108f: ff e0 jmpq *%rax 1091: 0f 1f 80 00 00 00 00 nopl 0x0(%rax) 1098: c3 retq 1099: 0f 1f 80 00 00 00 00 nopl 0x0(%rax)
00000000000010a0 <register_tm_clones>: 10a0: 48 8d 3d 89 2f 00 00 lea 0x2f89(%rip),%rdi # 4030 <__TMC_END__> 10a7: 48 8d 35 82 2f 00 00 lea 0x2f82(%rip),%rsi # 4030 <__TMC_END__> 10ae: 48 29 fe sub %rdi,%rsi 10b1: 48 89 f0 mov %rsi,%rax 10b4: 48 c1 ee 3f shr $0x3f,%rsi 10b8: 48 c1 f8 03 sar $0x3,%rax 10bc: 48 01 c6 add %rax,%rsi 10bf: 48 d1 fe sar %rsi 10c2: 74 14 je 10d8 <register_tm_clones+0x38> 10c4: 48 8b 05 25 2f 00 00 mov 0x2f25(%rip),%rax # 3ff0 <_ITM_registerTMCloneTable> 10cb: 48 85 c0 test %rax,%rax 10ce: 74 08 je 10d8 <register_tm_clones+0x38> 10d0: ff e0 jmpq *%rax 10d2: 66 0f 1f 44 00 00 nopw 0x0(%rax,%rax,1) 10d8: c3 retq 10d9: 0f 1f 80 00 00 00 00 nopl 0x0(%rax)
00000000000010e0 <__do_global_dtors_aux>: 10e0: f3 0f 1e fa endbr64 10e4: 80 3d 45 2f 00 00 00 cmpb $0x0,0x2f45(%rip) # 4030 <__TMC_END__> 10eb: 75 33 jne 1120 <__do_global_dtors_aux+0x40> 10ed: 55 push %rbp 10ee: 48 83 3d 02 2f 00 00 cmpq $0x0,0x2f02(%rip) # 3ff8 <__cxa_finalize@GLIBC_2.2.5> 10f5: 00 10f6: 48 89 e5 mov %rsp,%rbp 10f9: 74 0d je 1108 <__do_global_dtors_aux+0x28> 10fb: 48 8b 3d 26 2f 00 00 mov 0x2f26(%rip),%rdi # 4028 <__dso_handle> 1102: ff 15 f0 2e 00 00 callq *0x2ef0(%rip) # 3ff8 <__cxa_finalize@GLIBC_2.2.5> 1108: e8 63 ff ff ff callq 1070 <deregister_tm_clones> 110d: c6 05 1c 2f 00 00 01 movb $0x1,0x2f1c(%rip) # 4030 <__TMC_END__> 1114: 5d pop %rbp 1115: c3 retq 1116: 66 2e 0f 1f 84 00 00 nopw %cs:0x0(%rax,%rax,1) 111d: 00 00 00 1120: c3 retq 1121: 66 66 2e 0f 1f 84 00 data16 nopw %cs:0x0(%rax,%rax,1) 1128: 00 00 00 00 112c: 0f 1f 40 00 nopl 0x0(%rax)
0000000000001130 <frame_dummy>: 1130: f3 0f 1e fa endbr64 1134: e9 67 ff ff ff jmpq 10a0 <register_tm_clones>
0000000000001139 <add>: 1139: 8d 04 37 lea (%rdi,%rsi,1),%eax 113c: c3 retq
000000000000113d <main>: 113d: 48 83 ec 08 sub $0x8,%rsp 1141: be 06 00 00 00 mov $0x6,%esi 1146: bf 05 00 00 00 mov $0x5,%edi 114b: e8 e9 ff ff ff callq 1139 <add> 1150: 89 c6 mov %eax,%esi 1152: 48 8d 3d ab 0e 00 00 lea 0xeab(%rip),%rdi # 2004 <_IO_stdin_used+0x4> 1159: b8 00 00 00 00 mov $0x0,%eax 115e: e8 cd fe ff ff callq 1030 <printf@plt> 1163: b8 00 00 00 00 mov $0x0,%eax 1168: 48 83 c4 08 add $0x8,%rsp 116c: c3 retq 116d: 0f 1f 00 nopl (%rax)
0000000000001170 <__libc_csu_init>: 1170: f3 0f 1e fa endbr64 1174: 41 57 push %r15 1176: 4c 8d 3d 6b 2c 00 00 lea 0x2c6b(%rip),%r15 # 3de8 <__frame_dummy_init_array_entry> 117d: 41 56 push %r14 117f: 49 89 d6 mov %rdx,%r14 1182: 41 55 push %r13 1184: 49 89 f5 mov %rsi,%r13 1187: 41 54 push %r12 1189: 41 89 fc mov %edi,%r12d 118c: 55 push %rbp 118d: 48 8d 2d 5c 2c 00 00 lea 0x2c5c(%rip),%rbp # 3df0 <__init_array_end> 1194: 53 push %rbx 1195: 4c 29 fd sub %r15,%rbp 1198: 48 83 ec 08 sub $0x8,%rsp 119c: e8 5f fe ff ff callq 1000 <_init> 11a1: 48 c1 fd 03 sar $0x3,%rbp 11a5: 74 1f je 11c6 <__libc_csu_init+0x56> 11a7: 31 db xor %ebx,%ebx 11a9: 0f 1f 80 00 00 00 00 nopl 0x0(%rax) 11b0: 4c 89 f2 mov %r14,%rdx 11b3: 4c 89 ee mov %r13,%rsi 11b6: 44 89 e7 mov %r12d,%edi 11b9: 41 ff 14 df callq *(%r15,%rbx,8) 11bd: 48 83 c3 01 add $0x1,%rbx 11c1: 48 39 dd cmp %rbx,%rbp 11c4: 75 ea jne 11b0 <__libc_csu_init+0x40> 11c6: 48 83 c4 08 add $0x8,%rsp 11ca: 5b pop %rbx 11cb: 5d pop %rbp 11cc: 41 5c pop %r12 11ce: 41 5d pop %r13 11d0: 41 5e pop %r14 11d2: 41 5f pop %r15 11d4: c3 retq 11d5: 66 66 2e 0f 1f 84 00 data16 nopw %cs:0x0(%rax,%rax,1) 11dc: 00 00 00 00
00000000000011e0 <__libc_csu_fini>: 11e0: f3 0f 1e fa endbr64 11e4: c3 retq
Disassembly of section .fini:
00000000000011e8 <_fini>: 11e8: f3 0f 1e fa endbr64 11ec: 48 83 ec 08 sub $0x8,%rsp 11f0: 48 83 c4 08 add $0x8,%rsp 11f4: c3 retq
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注意一下 add 函数：
0000000000001139 <add>: 1139: 8d 04 37 lea (%rdi,%rsi,1),%eax 113c: c3 retq
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用寻址的方式完成了加法计算：
lea (%rdi,%rsi,1),%eax
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就相当于 eax=rdi+rsi*1，rdi和rsi是传参的两个寄存器。
这也是 gcc 优化程序的一种手段。
查看节
objdump -s main
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输出：
main： 文件格式 elf64-x86-64
Contents of section .interp: 02a8 2f6c6962 36342f6c 642d6c69 6e75782d /lib64/ld-linux- 02b8 7838362d 36342e73 6f2e3200 x86-64.so.2. Contents of section .note.gnu.build-id: 02c4 04000000 14000000 03000000 474e5500 ............GNU. 02d4 cd22e2f0 7545bdf9 2ae713c1 dba544d6 ."..uE..*.....D. 02e4 031eb047 ...G Contents of section .note.ABI-tag: 02e8 04000000 10000000 01000000 474e5500 ............GNU. 02f8 00000000 03000000 02000000 00000000 ................Contents of section .gnu.hash: 0308 01000000 01000000 01000000 00000000 ................ 0318 00000000 00000000 00000000 ............ Contents of section .dynsym: 0328 00000000 00000000 00000000 00000000 ................ 0338 00000000 00000000 3f000000 20000000 ........?... ... 0348 00000000 00000000 00000000 00000000 ................ 0358 0b000000 12000000 00000000 00000000 ................ 0368 00000000 00000000 21000000 12000000 ........!....... 0378 00000000 00000000 00000000 00000000 ................ 0388 5b000000 20000000 00000000 00000000 [... ........... 0398 00000000 00000000 6a000000 20000000 ........j... ... 03a8 00000000 00000000 00000000 00000000 ................ 03b8 12000000 22000000 00000000 00000000 ...."........... 03c8 00000000 00000000 ........ Contents of section .dynstr: 03d0 006c6962 632e736f 2e360070 72696e74 .libc.so.6.print 03e0 66005f5f 6378615f 66696e61 6c697a65 f.__cxa_finalize 03f0 005f5f6c 6962635f 73746172 745f6d61 .__libc_start_ma 0400 696e0047 4c494243 5f322e32 2e35005f in.GLIBC_2.2.5._ 0410 49544d5f 64657265 67697374 6572544d ITM_deregisterTM 0420 436c6f6e 65546162 6c65005f 5f676d6f CloneTable.__gmo 0430 6e5f7374 6172745f 5f005f49 544d5f72 n_start__._ITM_r 0440 65676973 74657254 4d436c6f 6e655461 egisterTMCloneTa 0450 626c6500 ble. Contents of section .gnu.version: 0454 00000000 02000200 00000000 0200 .............. Contents of section .gnu.version_r: 0468 01000100 01000000 10000000 00000000 ................ 0478 751a6909 00000200 33000000 00000000 u.i.....3.......Contents of section .rela.dyn: 0488 e83d0000 00000000 08000000 00000000 .=.............. 0498 30110000 00000000 f03d0000 00000000 0........=...... 04a8 08000000 00000000 e0100000 00000000 ................ 04b8 28400000 00000000 08000000 00000000 (@.............. 04c8 28400000 00000000 d83f0000 00000000 (@.......?...... 04d8 06000000 01000000 00000000 00000000 ................ 04e8 e03f0000 00000000 06000000 03000000 .?.............. 04f8 00000000 00000000 e83f0000 00000000 .........?...... 0508 06000000 04000000 00000000 00000000 ................ 0518 f03f0000 00000000 06000000 05000000 .?.............. 0528 00000000 00000000 f83f0000 00000000 .........?...... 0538 06000000 06000000 00000000 00000000 ................Contents of section .rela.plt: 0548 18400000 00000000 07000000 02000000 .@.............. 0558 00000000 00000000 ........ Contents of section .init: 1000 f30f1efa 4883ec08 488b05d9 2f000048 ....H...H.../..H 1010 85c07402 ffd04883 c408c3 ..t...H.... Contents of section .plt: 1020 ff35e22f 0000ff25 e42f0000 0f1f4000 .5./...%./....@. 1030 ff25e22f 00006800 000000e9 e0ffffff .%./..h.........Contents of section .text: 1040 f30f1efa 31ed4989 d15e4889 e24883e4 ....1.I..^H..H.. 1050 f050544c 8d058601 0000488d 0d0f0100 .PTL......H..... 1060 00488d3d d5000000 ff15722f 0000f490 .H.=......r/.... 1070 488d3db9 2f000048 8d05b22f 00004839 H.=./..H.../..H9 1080 f8741548 8b054e2f 00004885 c07409ff .t.H..N/..H..t.. 1090 e00f1f80 00000000 c30f1f80 00000000 ................ 10a0 488d3d89 2f000048 8d35822f 00004829 H.=./..H.5./..H) 10b0 fe4889f0 48c1ee3f 48c1f803 4801c648 .H..H..?H...H..H 10c0 d1fe7414 488b0525 2f000048 85c07408 ..t.H..%/..H..t. 10d0 ffe0660f 1f440000 c30f1f80 00000000 ..f..D.......... 10e0 f30f1efa 803d452f 00000075 33554883 .....=E/...u3UH. 10f0 3d022f00 00004889 e5740d48 8b3d262f =./...H..t.H.=&/ 1100 0000ff15 f02e0000 e863ffff ffc6051c .........c...... 1110 2f000001 5dc3662e 0f1f8400 00000000 /...].f......... 1120 c366662e 0f1f8400 00000000 0f1f4000 .ff...........@. 1130 f30f1efa e967ffff ff8d0437 c34883ec .....g.....7.H.. 1140 08be0600 0000bf05 000000e8 e9ffffff ................ 1150 89c6488d 3dab0e00 00b80000 0000e8cd ..H.=........... 1160 feffffb8 00000000 4883c408 c30f1f00 ........H....... 1170 f30f1efa 41574c8d 3d6b2c00 00415649 ....AWL.=k,..AVI 1180 89d64155 4989f541 544189fc 55488d2d ..AUI..ATA..UH.- 1190 5c2c0000 534c29fd 4883ec08 e85ffeff \,..SL).H...._.. 11a0 ff48c1fd 03741f31 db0f1f80 00000000 .H...t.1........ 11b0 4c89f24c 89ee4489 e741ff14 df4883c3 L..L..D..A...H.. 11c0 014839dd 75ea4883 c4085b5d 415c415d .H9.u.H...[]A\A] 11d0 415e415f c366662e 0f1f8400 00000000 A^A_.ff......... 11e0 f30f1efa c3 ..... Contents of section .fini: 11e8 f30f1efa 4883ec08 4883c408 c3 ....H...H.... Contents of section .rodata: 2000 01000200 68656c6c 6f20776f 726c6420 ....hello world 2010 25640a00 %d.. Contents of section .eh_frame_hdr: 2014 011b033b 38000000 06000000 0cf0ffff ...;8........... 2024 6c000000 2cf0ffff 54000000 25f1ffff l...,...T...%... 2034 94000000 29f1ffff a8000000 5cf1ffff ....).......\... 2044 c4000000 ccf1ffff 0c010000 ............ Contents of section .eh_frame: 2050 14000000 00000000 017a5200 01781001 .........zR..x.. 2060 1b0c0708 90010000 14000000 1c000000 ................ 2070 d0efffff 2f000000 00440710 00000000 ..../....D...... 2080 24000000 34000000 98efffff 20000000 $...4....... ... 2090 000e1046 0e184a0f 0b770880 003f1a3b ...F..J..w...?.; 20a0 2a332422 00000000 10000000 5c000000 *3$"........\... 20b0 89f0ffff 04000000 00000000 18000000 ................ 20c0 70000000 79f0ffff 30000000 00440e10 p...y...0....D.. 20d0 6b0e0800 00000000 44000000 8c000000 k.......D....... 20e0 90f0ffff 65000000 00460e10 8f02490e ....e....F....I. 20f0 188e0345 0e208d04 450e288c 05440e30 ...E. ..E.(..D.0 2100 8606480e 38830747 0e406e0e 38410e30 ..H.8..G.@n.8A.0 2110 410e2842 0e20420e 18420e10 420e0800 A.(B. B..B..B... 2120 10000000 d4000000 b8f0ffff 05000000 ................ 2130 00000000 00000000 ........ Contents of section .init_array: 3de8 30110000 00000000 0....... Contents of section .fini_array: 3df0 e0100000 00000000 ........ Contents of section .dynamic: 3df8 01000000 00000000 01000000 00000000 ................ 3e08 0c000000 00000000 00100000 00000000 ................ 3e18 0d000000 00000000 e8110000 00000000 ................ 3e28 19000000 00000000 e83d0000 00000000 .........=...... 3e38 1b000000 00000000 08000000 00000000 ................ 3e48 1a000000 00000000 f03d0000 00000000 .........=...... 3e58 1c000000 00000000 08000000 00000000 ................ 3e68 f5feff6f 00000000 08030000 00000000 ...o............ 3e78 05000000 00000000 d0030000 00000000 ................ 3e88 06000000 00000000 28030000 00000000 ........(....... 3e98 0a000000 00000000 84000000 00000000 ................ 3ea8 0b000000 00000000 18000000 00000000 ................ 3eb8 15000000 00000000 00000000 00000000 ................ 3ec8 03000000 00000000 00400000 00000000 .........@...... 3ed8 02000000 00000000 18000000 00000000 ................ 3ee8 14000000 00000000 07000000 00000000 ................ 3ef8 17000000 00000000 48050000 00000000 ........H....... 3f08 07000000 00000000 88040000 00000000 ................ 3f18 08000000 00000000 c0000000 00000000 ................ 3f28 09000000 00000000 18000000 00000000 ................ 3f38 fbffff6f 00000000 00000008 00000000 ...o............ 3f48 feffff6f 00000000 68040000 00000000 ...o....h....... 3f58 ffffff6f 00000000 01000000 00000000 ...o............ 3f68 f0ffff6f 00000000 54040000 00000000 ...o....T....... 3f78 f9ffff6f 00000000 03000000 00000000 ...o............ 3f88 00000000 00000000 00000000 00000000 ................ 3f98 00000000 00000000 00000000 00000000 ................ 3fa8 00000000 00000000 00000000 00000000 ................ 3fb8 00000000 00000000 00000000 00000000 ................ 3fc8 00000000 00000000 00000000 00000000 ................Contents of section .got: 3fd8 00000000 00000000 00000000 00000000 ................ 3fe8 00000000 00000000 00000000 00000000 ................ 3ff8 00000000 00000000 ........ Contents of section .got.plt: 4000 f83d0000 00000000 00000000 00000000 .=.............. 4010 00000000 00000000 36100000 00000000 ........6.......Contents of section .data: 4020 00000000 00000000 28400000 00000000 ........(@......Contents of section .comment: 0000 4743433a 2028474e 55292039 2e322e30 GCC: (GNU) 9.2.0 0010 00 .
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注意到 printf 中的常量字符串位于.rodata 节中。
反汇编指定符号
objdump --disassemble=add main
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输出：
main： 文件格式 elf64-x86-64
Disassembly of section .init:
Disassembly of section .plt:
Disassembly of section .text:
0000000000001139 <add>: 1139: 8d 04 37 lea (%rdi,%rsi,1),%eax 113c: c3 retq
Disassembly of section .fini:
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打印符号表内容
objdump -t main
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输出
main： 文件格式 elf64-x86-64
SYMBOL TABLE:00000000000002a8 l d .interp 0000000000000000 .interp00000000000002c4 l d .note.gnu.build-id 0000000000000000 .note.gnu.build-id00000000000002e8 l d .note.ABI-tag 0000000000000000 .note.ABI-tag0000000000000308 l d .gnu.hash 0000000000000000 .gnu.hash0000000000000328 l d .dynsym 0000000000000000 .dynsym00000000000003d0 l d .dynstr 0000000000000000 .dynstr0000000000000454 l d .gnu.version 0000000000000000 .gnu.version0000000000000468 l d .gnu.version_r 0000000000000000 .gnu.version_r0000000000000488 l d .rela.dyn 0000000000000000 .rela.dyn0000000000000548 l d .rela.plt 0000000000000000 .rela.plt0000000000001000 l d .init 0000000000000000 .init0000000000001020 l d .plt 0000000000000000 .plt0000000000001040 l d .text 0000000000000000 .text00000000000011e8 l d .fini 0000000000000000 .fini0000000000002000 l d .rodata 0000000000000000 .rodata0000000000002014 l d .eh_frame_hdr 0000000000000000 .eh_frame_hdr0000000000002050 l d .eh_frame 0000000000000000 .eh_frame0000000000003de8 l d .init_array 0000000000000000 .init_array0000000000003df0 l d .fini_array 0000000000000000 .fini_array0000000000003df8 l d .dynamic 0000000000000000 .dynamic0000000000003fd8 l d .got 0000000000000000 .got0000000000004000 l d .got.plt 0000000000000000 .got.plt0000000000004020 l d .data 0000000000000000 .data0000000000004030 l d .bss 0000000000000000 .bss0000000000000000 l d .comment 0000000000000000 .comment0000000000000000 l df *ABS* 0000000000000000 init.c0000000000000000 l df *ABS* 0000000000000000 crtstuff.c0000000000001070 l F .text 0000000000000000 deregister_tm_clones00000000000010a0 l F .text 0000000000000000 register_tm_clones00000000000010e0 l F .text 0000000000000000 __do_global_dtors_aux0000000000004030 l O .bss 0000000000000001 completed.73920000000000003df0 l O .fini_array 0000000000000000 __do_global_dtors_aux_fini_array_entry0000000000001130 l F .text 0000000000000000 frame_dummy0000000000003de8 l O .init_array 0000000000000000 __frame_dummy_init_array_entry0000000000000000 l df *ABS* 0000000000000000 main.c0000000000000000 l df *ABS* 0000000000000000 crtstuff.c0000000000002134 l O .eh_frame 0000000000000000 __FRAME_END__0000000000000000 l df *ABS* 0000000000000000 0000000000003df0 l .init_array 0000000000000000 __init_array_end0000000000003df8 l O .dynamic 0000000000000000 _DYNAMIC0000000000003de8 l .init_array 0000000000000000 __init_array_start0000000000002014 l .eh_frame_hdr 0000000000000000 __GNU_EH_FRAME_HDR0000000000004000 l O .got.plt 0000000000000000 _GLOBAL_OFFSET_TABLE_0000000000001000 l F .init 0000000000000000 _init00000000000011e0 g F .text 0000000000000005 __libc_csu_fini0000000000000000 w *UND* 0000000000000000 _ITM_deregisterTMCloneTable0000000000004020 w .data 0000000000000000 data_start0000000000001139 g F .text 0000000000000004 add0000000000004030 g .data 0000000000000000 _edata00000000000011e8 g F .fini 0000000000000000 .hidden _fini0000000000000000 F *UND* 0000000000000000 printf@@GLIBC_2.2.50000000000000000 F *UND* 0000000000000000 __libc_start_main@@GLIBC_2.2.50000000000004020 g .data 0000000000000000 __data_start0000000000000000 w *UND* 0000000000000000 __gmon_start__0000000000004028 g O .data 0000000000000000 .hidden __dso_handle0000000000002000 g O .rodata 0000000000000004 _IO_stdin_used0000000000001170 g F .text 0000000000000065 __libc_csu_init0000000000004038 g .bss 0000000000000000 _end0000000000001040 g F .text 000000000000002f _start0000000000004030 g .bss 0000000000000000 __bss_start000000000000113d g F .text 0000000000000030 main0000000000004030 g O .data 0000000000000000 .hidden __TMC_END__0000000000000000 w *UND* 0000000000000000 _ITM_registerTMCloneTable0000000000000000 w F *UND* 0000000000000000 __cxa_finalize@@GLIBC_2.2.5
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打印动态符号表(外部链接)
objdump -T main
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输出：
main： 文件格式 elf64-x86-64
DYNAMIC SYMBOL TABLE:0000000000000000 w D *UND* 0000000000000000 _ITM_deregisterTMCloneTable0000000000000000 DF *UND* 0000000000000000 GLIBC_2.2.5 printf0000000000000000 DF *UND* 0000000000000000 GLIBC_2.2.5 __libc_start_main0000000000000000 w D *UND* 0000000000000000 __gmon_start__0000000000000000 w D *UND* 0000000000000000 _ITM_registerTMCloneTable0000000000000000 w DF *UND* 0000000000000000 GLIBC_2.2.5 __cxa_finalize
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打印重定位信息
objdump -r main
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输出
main： 文件格式 elf64-x86-64
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因为文件是可执行文件，所有没有可重定位信息。
打印动态可重定位信息
objdump -R main
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main： 文件格式 elf64-x86-64
DYNAMIC RELOCATION RECORDSOFFSET TYPE VALUE 0000000000003de8 R_X86_64_RELATIVE *ABS*+0x00000000000011300000000000003df0 R_X86_64_RELATIVE *ABS*+0x00000000000010e00000000000004028 R_X86_64_RELATIVE *ABS*+0x00000000000040280000000000003fd8 R_X86_64_GLOB_DAT _ITM_deregisterTMCloneTable0000000000003fe0 R_X86_64_GLOB_DAT __libc_start_main@GLIBC_2.2.50000000000003fe8 R_X86_64_GLOB_DAT __gmon_start__0000000000003ff0 R_X86_64_GLOB_DAT _ITM_registerTMCloneTable0000000000003ff8 R_X86_64_GLOB_DAT __cxa_finalize@GLIBC_2.2.50000000000004018 R_X86_64_JUMP_SLOT printf@GLIBC_2.2.5
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动态链接库的可重定位信息
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版权声明: 本文为 InfoQ 作者【SkyFire】的原创文章。
原文链接:【http://xie.infoq.cn/article/c67cdb09707e62c5fc09356d4】。文章转载请联系作者。
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