1

yasm在 linux ( ) 上尝试从汇编代码 ( ) 调用 c 函数时x86-64，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：

它提示：

bash: ./a.out: 没有这样的文件或目录

但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
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 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:
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     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:
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     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 
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     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 
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    12: 0000000000600390     0 SECTION LOCAL  DEFAULT   12 
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    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):
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      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:
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  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，是代码错误吗？还是我以错误的方式编译它？
4

2 回答 2

2

刚刚运行您的示例并遇到了同样的问题。
原因是我的情况是不正确的动态链接器（ELF 解释器）。
要验证这是问题所在，请键入file ./a.out您应该得到类似于以下输出的内容：
a.out: ELF 64-bit LSB executable, x86-64, version 1 (SYSV), dynamically linked, interpreter /lib/ld64.so.1, not stripped

ld的默认选择的动态链接器 ( /lib/ld64.so.1) 在大多数 Linux 系统上不存在，因此存在问题。您可以使用 patchelf (apt-get install patchelf) 和以下命令来更正此问题：

patchelf --set-interpreter [path_to_interpreter] ./a.out

您可以通过键入获得应用作 ELF 解释器的正确路径file /bin/ls- 将打印标准动态链接器路径。（此外，readelf可以打印，以及更多）。

最好的方法是首先使用ld'-dynamic-linker标志正确设置 elf 标头中的 INTERP 部分。

有关使用或不使用 libc 将 asm 构建/链接到静态或动态二进制文件的更多详细信息，另请参阅此答案。

于 2016-06-21T07:03:35.310 回答
2

（正如@Peter Cordes 所建议的，我想给出一个总结问题和其他答案下的评论的答案，以便将来的搜索者更清楚。）

原始代码和编译/链接策略中的问题：

  • 更好地使用main而不是_start. 原因：因为（最初在@Michael Petch 的评论中提到），C 运行时包含一个_start标签，这是冲突，当链接使用gcc. 尽管可以通过-nostartfiles在链接时向 gcc 添加选项来解决此问题，但简单gcc xxx.o的是更简单。因此，只需使用main而不是_start.

  • 退出 main viaret而不是int 0x80. 原因：因为（最初在@Michael Petch 的评论中提到），ret将有助于刷新标准输出，而int 0x80不会，所以使用int 0x80不会看到hello world控制台。调用C函数exit是另一种解决方案，但它是对c的额外函数调用，因此使用ret效率更高，它将_start从c运行时返回。

  • gcc通过而不是更好的链接ld。原因：因为（如@Peter Cordes 和@Michael Petch 的评论中所述），C 运行时默认包含在 gcc 中，因此您不需要像-lc使用 gcc 时那样添加选项。但ld不要包括 C 运行时。所以，再一次，使用gcc使它更简单。

有关详细信息，请参阅问题和其他答案下的评论。

（所以，根据上面的解释。）

解决问题的步骤：

  • 在汇编源代码中更改_start为main,
  • ret通过而不是退出程序int 0x80。
  • 编译通过yasm，例如yasm -f elf64 function_call_c.asm -g dwarf2
  • 链接方式gcc，例如gcc function_call_c.o

（这是新版本的代码。）

function_call_c.asm：

; yasm assembly program, instruction - call c function
; compile: yasm -f elf64 function_call_c.asm -g dwarf2 && gcc function_call_c.o
; execute: ./a.out
; check printed char count (immediately after execution): echo $?

section .data
msg_format db 'hello world',0x0A,0

section .text
extern printf
extern exit
global main

main:
    mov rax, 0
    lea rdi, [msg_format]
    call printf

_exit:
    ; eax now contains count of chars printed, due to previous 'printf' call,
    ret; return from main, this will flush the output,
于 2016-06-21T16:47:15.843 回答