<分区>
当尝试在 linux (x86-64) 上从汇编代码 (yasm) 调用 c 函数时, 执行失败。
代码
function_call_c.asm:
; yasm assembly program, instruction - call c function
; compile: yasm -f elf64 function_call_c.asm -g dwarf2 && ld function_call_c.o -lc
; execute: ./a.out
section .data
msg_format db "hello"
section .text
extern printf
global _start
_start:
lea rdi, [msg_format]
call printf
_exit:
; exit
mov eax,1
mov ebx,5
int 0x80
编译:
yasm -f elf64 function_call_c.asm -g dwarf2 && ld function_call_c.o -lc
执行时:
提示:
bash: ./a.out: No such file or directory
但是a.out确实存在，并且有执行权限。
使用objdump，获取可执行文件的信息:
a.out: file format elf64-x86-64
Disassembly of section .interp:
0000000000400158 <.interp>:
400158: 2f (bad)
400159: 6c insb (%dx),%es:(%rdi)
40015a: 69 62 2f 6c 64 36 34 imul $0x3436646c,0x2f(%rdx),%esp
400161: 2e 73 6f jae,pn 4001d3 <printf@plt-0x4d>
400164: 2e 31 00 xor %eax,%cs:(%rax)
Disassembly of section .hash:
0000000000400168 <.hash>:
400168: 01 00 add %eax,(%rax)
40016a: 00 00 add %al,(%rax)
40016c: 02 00 add (%rax),%al
40016e: 00 00 add %al,(%rax)
400170: 01 00 add %eax,(%rax)
...
Disassembly of section .dynsym:
0000000000400180 <.dynsym>:
...
400198: 0b 00 or (%rax),%eax
40019a: 00 00 add %al,(%rax)
40019c: 12 00 adc (%rax),%al
...
Disassembly of section .dynstr:
00000000004001b0 <.dynstr>:
4001b0: 00 6c 69 62 add %ch,0x62(%rcx,%rbp,2)
4001b4: 63 2e movslq (%rsi),%ebp
4001b6: 73 6f jae 400227 <printf@plt+0x7>
4001b8: 2e 36 00 70 72 cs add %dh,%cs:%ss:0x72(%rax)
4001bd: 69 6e 74 66 00 47 4c imul $0x4c470066,0x74(%rsi),%ebp
4001c4: 49 rex.WB
4001c5: 42 rex.X
4001c6: 43 5f rex.XB pop %r15
4001c8: 32 2e xor (%rsi),%ch
4001ca: 32 2e xor (%rsi),%ch
4001cc: 35 .byte 0x35
...
Disassembly of section .gnu.version:
00000000004001ce <.gnu.version>:
4001ce: 00 00 add %al,(%rax)
4001d0: 02 00 add (%rax),%al
Disassembly of section .gnu.version_r:
00000000004001d8 <.gnu.version_r>:
4001d8: 01 00 add %eax,(%rax)
4001da: 01 00 add %eax,(%rax)
4001dc: 01 00 add %eax,(%rax)
4001de: 00 00 add %al,(%rax)
4001e0: 10 00 adc %al,(%rax)
4001e2: 00 00 add %al,(%rax)
4001e4: 00 00 add %al,(%rax)
4001e6: 00 00 add %al,(%rax)
4001e8: 75 1a jne 400204 <printf@plt-0x1c>
4001ea: 69 09 00 00 02 00 imul $0x20000,(%rcx),%ecx
4001f0: 12 00 adc (%rax),%al
4001f2: 00 00 add %al,(%rax)
4001f4: 00 00 add %al,(%rax)
...
Disassembly of section .rela.plt:
00000000004001f8 <.rela.plt>:
4001f8: a8 03 test $0x3,%al
4001fa: 60 (bad)
4001fb: 00 00 add %al,(%rax)
4001fd: 00 00 add %al,(%rax)
4001ff: 00 07 add %al,(%rdi)
400201: 00 00 add %al,(%rax)
400203: 00 01 add %al,(%rcx)
...
Disassembly of section .plt:
0000000000400210 <printf@plt-0x10>:
400210: ff 35 82 01 20 00 pushq 0x200182(%rip) # 600398 <_GLOBAL_OFFSET_TABLE_+0x8>
400216: ff 25 84 01 20 00 jmpq *0x200184(%rip) # 6003a0 <_GLOBAL_OFFSET_TABLE_+0x10>
40021c: 0f 1f 40 00 nopl 0x0(%rax)
0000000000400220 <printf@plt>:
400220: ff 25 82 01 20 00 jmpq *0x200182(%rip) # 6003a8 <_GLOBAL_OFFSET_TABLE_+0x18>
400226: 68 00 00 00 00 pushq $0x0
40022b: e9 e0 ff ff ff jmpq 400210 <printf@plt-0x10>
Disassembly of section .text:
0000000000400230 <_start>:
400230: 48 8d 3c 25 b0 03 60 lea 0x6003b0,%rdi
400237: 00
400238: e8 e3 ff ff ff callq 400220 <printf@plt>
000000000040023d <_exit>:
40023d: b8 01 00 00 00 mov $0x1,%eax
400242: bb 05 00 00 00 mov $0x5,%ebx
400247: cd 80 int $0x80
Disassembly of section .dynamic:
0000000000600250 <_DYNAMIC>:
600250: 01 00 add %eax,(%rax)
600252: 00 00 add %al,(%rax)
600254: 00 00 add %al,(%rax)
600256: 00 00 add %al,(%rax)
600258: 01 00 add %eax,(%rax)
60025a: 00 00 add %al,(%rax)
60025c: 00 00 add %al,(%rax)
60025e: 00 00 add %al,(%rax)
600260: 04 00 add $0x0,%al
600262: 00 00 add %al,(%rax)
600264: 00 00 add %al,(%rax)
600266: 00 00 add %al,(%rax)
600268: 68 01 40 00 00 pushq $0x4001
60026d: 00 00 add %al,(%rax)
60026f: 00 05 00 00 00 00 add %al,0x0(%rip) # 600275 <_DYNAMIC+0x25>
600275: 00 00 add %al,(%rax)
600277: 00 b0 01 40 00 00 add %dh,0x4001(%rax)
60027d: 00 00 add %al,(%rax)
60027f: 00 06 add %al,(%rsi)
600281: 00 00 add %al,(%rax)
600283: 00 00 add %al,(%rax)
600285: 00 00 add %al,(%rax)
600287: 00 80 01 40 00 00 add %al,0x4001(%rax)
60028d: 00 00 add %al,(%rax)
60028f: 00 0a add %cl,(%rdx)
600291: 00 00 add %al,(%rax)
600293: 00 00 add %al,(%rax)
600295: 00 00 add %al,(%rax)
600297: 00 1e add %bl,(%rsi)
600299: 00 00 add %al,(%rax)
60029b: 00 00 add %al,(%rax)
60029d: 00 00 add %al,(%rax)
60029f: 00 0b add %cl,(%rbx)
6002a1: 00 00 add %al,(%rax)
6002a3: 00 00 add %al,(%rax)
6002a5: 00 00 add %al,(%rax)
6002a7: 00 18 add %bl,(%rax)
6002a9: 00 00 add %al,(%rax)
6002ab: 00 00 add %al,(%rax)
6002ad: 00 00 add %al,(%rax)
6002af: 00 15 00 00 00 00 add %dl,0x0(%rip) # 6002b5 <_DYNAMIC+0x65>
...
6002bd: 00 00 add %al,(%rax)
6002bf: 00 03 add %al,(%rbx)
6002c1: 00 00 add %al,(%rax)
6002c3: 00 00 add %al,(%rax)
6002c5: 00 00 add %al,(%rax)
6002c7: 00 90 03 60 00 00 add %dl,0x6003(%rax)
6002cd: 00 00 add %al,(%rax)
6002cf: 00 02 add %al,(%rdx)
6002d1: 00 00 add %al,(%rax)
6002d3: 00 00 add %al,(%rax)
6002d5: 00 00 add %al,(%rax)
6002d7: 00 18 add %bl,(%rax)
6002d9: 00 00 add %al,(%rax)
6002db: 00 00 add %al,(%rax)
6002dd: 00 00 add %al,(%rax)
6002df: 00 14 00 add %dl,(%rax,%rax,1)
6002e2: 00 00 add %al,(%rax)
6002e4: 00 00 add %al,(%rax)
6002e6: 00 00 add %al,(%rax)
6002e8: 07 (bad)
6002e9: 00 00 add %al,(%rax)
6002eb: 00 00 add %al,(%rax)
6002ed: 00 00 add %al,(%rax)
6002ef: 00 17 add %dl,(%rdi)
6002f1: 00 00 add %al,(%rax)
6002f3: 00 00 add %al,(%rax)
6002f5: 00 00 add %al,(%rax)
6002f7: 00 f8 add %bh,%al
6002f9: 01 40 00 add %eax,0x0(%rax)
6002fc: 00 00 add %al,(%rax)
6002fe: 00 00 add %al,(%rax)
600300: fe (bad)
600301: ff (bad)
600302: ff 6f 00 ljmpq *0x0(%rdi)
600305: 00 00 add %al,(%rax)
600307: 00 d8 add %bl,%al
600309: 01 40 00 add %eax,0x0(%rax)
60030c: 00 00 add %al,(%rax)
60030e: 00 00 add %al,(%rax)
600310: ff (bad)
600311: ff (bad)
600312: ff 6f 00 ljmpq *0x0(%rdi)
600315: 00 00 add %al,(%rax)
600317: 00 01 add %al,(%rcx)
600319: 00 00 add %al,(%rax)
60031b: 00 00 add %al,(%rax)
60031d: 00 00 add %al,(%rax)
60031f: 00 f0 add %dh,%al
600321: ff (bad)
600322: ff 6f 00 ljmpq *0x0(%rdi)
600325: 00 00 add %al,(%rax)
600327: 00 ce add %cl,%dh
600329: 01 40 00 add %eax,0x0(%rax)
...
Disassembly of section .got.plt:
0000000000600390 <_GLOBAL_OFFSET_TABLE_>:
600390: 50 push %rax
600391: 02 60 00 add 0x0(%rax),%ah
...
6003a8: 26 02 40 00 add %es:0x0(%rax),%al
6003ac: 00 00 add %al,(%rax)
...
Disassembly of section .data:
00000000006003b0 <msg_format>:
6003b0: 68 65 6c 6c 6f pushq $0x6f6c6c65
Disassembly of section .debug_aranges:
0000000000000000 <.debug_aranges>:
0: 2c 00 sub $0x0,%al
2: 00 00 add %al,(%rax)
4: 02 00 add (%rax),%al
6: 00 00 add %al,(%rax)
8: 00 00 add %al,(%rax)
a: 08 00 or %al,(%rax)
c: 00 00 add %al,(%rax)
e: 00 00 add %al,(%rax)
10: 30 02 xor %al,(%rdx)
12: 40 00 00 add %al,(%rax)
15: 00 00 add %al,(%rax)
17: 00 19 add %bl,(%rcx)
...
Disassembly of section .debug_info:
0000000000000000 <.debug_info>:
0: 85 00 test %eax,(%rax)
2: 00 00 add %al,(%rax)
4: 02 00 add (%rax),%al
6: 00 00 add %al,(%rax)
8: 00 00 add %al,(%rax)
a: 08 01 or %al,(%rcx)
c: 00 00 add %al,(%rax)
e: 00 00 add %al,(%rax)
10: 30 02 xor %al,(%rdx)
12: 40 00 00 add %al,(%rax)
15: 00 00 add %al,(%rax)
17: 00 49 02 add %cl,0x2(%rcx)
1a: 40 00 00 add %al,(%rax)
1d: 00 00 add %al,(%rax)
1f: 00 66 75 add %ah,0x75(%rsi)
22: 6e outsb %ds:(%rsi),(%dx)
23: 63 74 69 6f movslq 0x6f(%rcx,%rbp,2),%esi
27: 6e outsb %ds:(%rsi),(%dx)
28: 5f pop %rdi
29: 63 61 6c movslq 0x6c(%rcx),%esp
2c: 6c insb (%dx),%es:(%rdi)
2d: 5f pop %rdi
2e: 63 2e movslq (%rsi),%ebp
30: 61 (bad)
31: 73 6d jae a0 <printf@plt-0x400180>
33: 00 2f add %ch,(%rdi)
35: 6d insl (%dx),%es:(%rdi)
36: 6e outsb %ds:(%rsi),(%dx)
37: 74 2f je 68 <printf@plt-0x4001b8>
39: 73 74 jae af <printf@plt-0x400171>
3b: 61 (bad)
3c: 72 2f jb 6d <printf@plt-0x4001b3>
3e: 67 69 74 5f 72 65 70 imul $0x736f7065,0x72(%edi,%ebx,2),%esi
45: 6f 73
47: 69 74 6f 72 79 2f 77 imul $0x6f772f79,0x72(%rdi,%rbp,2),%esi
4e: 6f
4f: 72 6b jb bc <printf@plt-0x400164>
51: 73 70 jae c3 <printf@plt-0x40015d>
53: 61 (bad)
54: 63 65 2f movslq 0x2f(%rbp),%esp
57: 61 (bad)
58: 73 73 jae cd <printf@plt-0x400153>
5a: 65 gs
5b: 6d insl (%dx),%es:(%rdi)
5c: 62 (bad)
5d: 6c insb (%dx),%es:(%rdi)
5e: 79 5f jns bf <printf@plt-0x400161>
60: 77 6f ja d1 <printf@plt-0x40014f>
62: 72 6b jb cf <printf@plt-0x400151>
64: 70 6c jo d2 <printf@plt-0x40014e>
66: 61 (bad)
67: 63 65 2f movslq 0x2f(%rbp),%esp
6a: 79 61 jns cd <printf@plt-0x400153>
6c: 73 6d jae db <printf@plt-0x400145>
6e: 2f (bad)
6f: 69 6e 73 74 72 75 63 imul $0x63757274,0x73(%rsi),%ebp
76: 74 69 je e1 <printf@plt-0x40013f>
78: 6f outsl %ds:(%rsi),(%dx)
79: 6e outsb %ds:(%rsi),(%dx)
7a: 2f (bad)
7b: 00 79 61 add %bh,0x61(%rcx)
7e: 73 6d jae ed <printf@plt-0x400133>
80: 20 31 and %dh,(%rcx)
82: 2e 32 2e xor %cs:(%rsi),%ch
85: 30 00 xor %al,(%rax)
87: 01 .byte 0x1
88: 80 .byte 0x80
Disassembly of section .debug_abbrev:
0000000000000000 <.debug_abbrev>:
0: 01 11 add %edx,(%rcx)
2: 00 10 add %dl,(%rax)
4: 06 (bad)
5: 11 01 adc %eax,(%rcx)
7: 12 01 adc (%rcx),%al
9: 03 08 add (%rax),%ecx
b: 1b 08 sbb (%rax),%ecx
d: 25 08 13 05 00 and $0x51308,%eax
...
Disassembly of section .debug_line:
0000000000000000 <.debug_line>:
0: 47 00 00 rex.RXB add %r8b,(%r8)
3: 00 02 add %al,(%rdx)
5: 00 2a add %ch,(%rdx)
7: 00 00 add %al,(%rax)
9: 00 01 add %al,(%rcx)
b: 01 fb add %edi,%ebx
d: 0e (bad)
e: 0d 00 01 01 01 or $0x1010100,%eax
13: 01 00 add %eax,(%rax)
15: 00 00 add %al,(%rax)
17: 01 00 add %eax,(%rax)
19: 00 01 add %al,(%rcx)
1b: 00 66 75 add %ah,0x75(%rsi)
1e: 6e outsb %ds:(%rsi),(%dx)
1f: 63 74 69 6f movslq 0x6f(%rcx,%rbp,2),%esi
23: 6e outsb %ds:(%rsi),(%dx)
24: 5f pop %rdi
25: 63 61 6c movslq 0x6c(%rcx),%esp
28: 6c insb (%dx),%es:(%rdi)
29: 5f pop %rdi
2a: 63 2e movslq (%rsi),%ebp
2c: 61 (bad)
2d: 73 6d jae 9c <printf@plt-0x400184>
2f: 00 00 add %al,(%rax)
31: 00 00 add %al,(%rax)
33: 00 00 add %al,(%rax)
35: 09 02 or %eax,(%rdx)
37: 30 02 xor %al,(%rdx)
39: 40 00 00 add %al,(%rax)
3c: 00 00 add %al,(%rax)
3e: 00 03 add %al,(%rbx)
40: 0c 01 or $0x1,%al
42: 83 5d 59 59 sbbl $0x59,0x59(%rbp)
46: 02 02 add (%rdx),%al
48: 00 01 add %al,(%rcx)
4a: 01 .byte 0x1
使用readelf，获取可执行文件的信息:
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
Entry point address: 0x400230
Start of program headers: 64 (bytes into file)
Start of section headers: 1432 (bytes into file)
Flags: 0x0
Size of this header: 64 (bytes)
Size of program headers: 56 (bytes)
Number of program headers: 5
Size of section headers: 64 (bytes)
Number of section headers: 21
Section header string table index: 18
Section Headers:
[Nr] Name Type Address Offset
Size EntSize Flags Link Info Align
[ 0] NULL 0000000000000000 00000000
0000000000000000 0000000000000000 0 0 0
[ 1] .interp PROGBITS 0000000000400158 00000158
000000000000000f 0000000000000000 A 0 0 1
[ 2] .hash HASH 0000000000400168 00000168
0000000000000014 0000000000000004 A 3 0 8
[ 3] .dynsym DYNSYM 0000000000400180 00000180
0000000000000030 0000000000000018 A 4 1 8
[ 4] .dynstr STRTAB 00000000004001b0 000001b0
000000000000001e 0000000000000000 A 0 0 1
[ 5] .gnu.version VERSYM 00000000004001ce 000001ce
0000000000000004 0000000000000002 A 3 0 2
[ 6] .gnu.version_r VERNEED 00000000004001d8 000001d8
0000000000000020 0000000000000000 A 4 1 8
[ 7] .rela.plt RELA 00000000004001f8 000001f8
0000000000000018 0000000000000018 A 3 8 8
[ 8] .plt PROGBITS 0000000000400210 00000210
0000000000000020 0000000000000010 AX 0 0 16
[ 9] .text PROGBITS 0000000000400230 00000230
0000000000000019 0000000000000000 AX 0 0 16
[10] .eh_frame PROGBITS 0000000000400250 00000250
0000000000000000 0000000000000000 A 0 0 8
[11] .dynamic DYNAMIC 0000000000600250 00000250
0000000000000140 0000000000000010 WA 4 0 8
[12] .got.plt PROGBITS 0000000000600390 00000390
0000000000000020 0000000000000008 WA 0 0 8
[13] .data PROGBITS 00000000006003b0 000003b0
0000000000000005 0000000000000000 WA 0 0 4
[14] .debug_aranges PROGBITS 0000000000000000 000003c0
0000000000000030 0000000000000000 0 0 16
[15] .debug_info PROGBITS 0000000000000000 000003f0
0000000000000089 0000000000000000 0 0 1
[16] .debug_abbrev PROGBITS 0000000000000000 00000479
0000000000000014 0000000000000000 0 0 1
[17] .debug_line PROGBITS 0000000000000000 0000048d
000000000000004b 0000000000000000 0 0 1
[18] .shstrtab STRTAB 0000000000000000 000004d8
00000000000000bc 0000000000000000 0 0 1
[19] .symtab SYMTAB 0000000000000000 00000ad8
00000000000002b8 0000000000000018 20 24 8
[20] .strtab STRTAB 0000000000000000 00000d90
0000000000000078 0000000000000000 0 0 1
Key to Flags:
W (write), A (alloc), X (execute), M (merge), S (strings), l (large)
I (info), L (link order), G (group), T (TLS), E (exclude), x (unknown)
O (extra OS processing required) o (OS specific), p (processor specific)
There are no section groups in this file.
Program Headers:
Type Offset VirtAddr PhysAddr
FileSiz MemSiz Flags Align
PHDR 0x0000000000000040 0x0000000000400040 0x0000000000400040
0x0000000000000118 0x0000000000000118 R E 8
INTERP 0x0000000000000158 0x0000000000400158 0x0000000000400158
0x000000000000000f 0x000000000000000f R 1
[Requesting program interpreter: /lib/ld64.so.1]
LOAD 0x0000000000000000 0x0000000000400000 0x0000000000400000
0x0000000000000250 0x0000000000000250 R E 200000
LOAD 0x0000000000000250 0x0000000000600250 0x0000000000600250
0x0000000000000165 0x0000000000000165 RW 200000
DYNAMIC 0x0000000000000250 0x0000000000600250 0x0000000000600250
0x0000000000000140 0x0000000000000140 RW 8
Section to Segment mapping:
Segment Sections...
00
01 .interp
02 .interp .hash .dynsym .dynstr .gnu.version .gnu.version_r .rela.plt .plt .text
03 .dynamic .got.plt .data
04 .dynamic
Dynamic section at offset 0x250 contains 15 entries:
Tag Type Name/Value
0x0000000000000001 (NEEDED) Shared library: [libc.so.6]
0x0000000000000004 (HASH) 0x400168
0x0000000000000005 (STRTAB) 0x4001b0
0x0000000000000006 (SYMTAB) 0x400180
0x000000000000000a (STRSZ) 30 (bytes)
0x000000000000000b (SYMENT) 24 (bytes)
0x0000000000000015 (DEBUG) 0x0
0x0000000000000003 (PLTGOT) 0x600390
0x0000000000000002 (PLTRELSZ) 24 (bytes)
0x0000000000000014 (PLTREL) RELA
0x0000000000000017 (JMPREL) 0x4001f8
0x000000006ffffffe (VERNEED) 0x4001d8
0x000000006fffffff (VERNEEDNUM) 1
0x000000006ffffff0 (VERSYM) 0x4001ce
0x0000000000000000 (NULL) 0x0
Relocation section '.rela.plt' at offset 0x1f8 contains 1 entries:
Offset Info Type Sym. Value Sym. Name + Addend
0000006003a8 000100000007 R_X86_64_JUMP_SLO 0000000000000000 printf + 0
The decoding of unwind sections for machine type Advanced Micro Devices X86-64 is not currently supported.
Symbol table '.dynsym' contains 2 entries:
Num: Value Size Type Bind Vis Ndx Name
0: 0000000000000000 0 NOTYPE LOCAL DEFAULT UND
1: 0000000000000000 0 FUNC GLOBAL DEFAULT UND printf@GLIBC_2.2.5 (2)
Symbol table '.symtab' contains 29 entries:
Num: Value Size Type Bind Vis Ndx Name
0: 0000000000000000 0 NOTYPE LOCAL DEFAULT UND
1: 0000000000400158 0 SECTION LOCAL DEFAULT 1
2: 0000000000400168 0 SECTION LOCAL DEFAULT 2
3: 0000000000400180 0 SECTION LOCAL DEFAULT 3
4: 00000000004001b0 0 SECTION LOCAL DEFAULT 4
5: 00000000004001ce 0 SECTION LOCAL DEFAULT 5
6: 00000000004001d8 0 SECTION LOCAL DEFAULT 6
7: 00000000004001f8 0 SECTION LOCAL DEFAULT 7
8: 0000000000400210 0 SECTION LOCAL DEFAULT 8
9: 0000000000400230 0 SECTION LOCAL DEFAULT 9
10: 0000000000400250 0 SECTION LOCAL DEFAULT 10
11: 0000000000600250 0 SECTION LOCAL DEFAULT 11
12: 0000000000600390 0 SECTION LOCAL DEFAULT 12
13: 00000000006003b0 0 SECTION LOCAL DEFAULT 13
14: 0000000000000000 0 SECTION LOCAL DEFAULT 14
15: 0000000000000000 0 SECTION LOCAL DEFAULT 15
16: 0000000000000000 0 SECTION LOCAL DEFAULT 16
17: 0000000000000000 0 SECTION LOCAL DEFAULT 17
18: 0000000000000000 0 FILE LOCAL DEFAULT ABS function_call_c.asm
19: 000000000040023d 0 NOTYPE LOCAL DEFAULT 9 _exit
20: 00000000006003b0 0 NOTYPE LOCAL DEFAULT 13 msg_format
21: 0000000000000000 0 FILE LOCAL DEFAULT ABS
22: 0000000000600250 0 OBJECT LOCAL DEFAULT 11 _DYNAMIC
23: 0000000000600390 0 OBJECT LOCAL DEFAULT 12 _GLOBAL_OFFSET_TABLE_
24: 00000000006003b5 0 NOTYPE GLOBAL DEFAULT 13 _edata
25: 0000000000000000 0 FUNC GLOBAL DEFAULT UND printf@@GLIBC_2.2.5
26: 00000000006003b8 0 NOTYPE GLOBAL DEFAULT 13 _end
27: 0000000000400230 0 NOTYPE GLOBAL DEFAULT 9 _start
28: 00000000006003b5 0 NOTYPE GLOBAL DEFAULT 13 __bss_start
Histogram for bucket list length (total of 1 buckets):
Length Number % of total Coverage
0 0 ( 0.0%)
1 1 (100.0%) 100.0%
Version symbols section '.gnu.version' contains 2 entries:
Addr: 00000000004001ce Offset: 0x0001ce Link: 3 (.dynsym)
000: 0 (*local*) 2 (GLIBC_2.2.5)
Version needs section '.gnu.version_r' contains 1 entries:
Addr: 0x00000000004001d8 Offset: 0x0001d8 Link: 4 (.dynstr)
000000: Version: 1 File: libc.so.6 Cnt: 1
0x0010: Name: GLIBC_2.2.5 Flags: none Version: 2
问题是:
- 为什么执行失败，是代码错了吗？或者我以错误的方式编译它？