Graphics Programs Reference
In-Depth Information
0xbffff7d0:
0xb7ff47b0 0x08048510 0xbffff7e8
0x080484bb
0xbffff7e0:
0xbffff9b7 0x08048510 0xbffff848 0xb7eafebc
0xbffff7f0: 0x00000002 0xbffff874 0xbffff880 0xb8001898
0xbffff800: 0x00000000 0x00000001 0x00000001 0x00000000
0xbffff810: 0xb7fd6ff4 0xb8000ce0 0x00000000 0xbffff848
(gdb) x/32xb 0xbffff9b7
0xbffff9b7: 0x41 0x41 0x41 0x41 0x41 0x41 0x41 0x41
0xbffff9bf: 0x41 0x41 0x41 0x41 0x41 0x41 0x41 0x41
0xbffff9c7: 0x41 0x41 0x41 0x41 0x41 0x41 0x41 0x41
0xbffff9cf: 0x41 0x41 0x41 0x41 0x41 0x41 0x00 0x53
(gdb) x/s 0xbffff9b7
0xbffff9b7: 'A' <repeats 30 times>
(gdb)
The return address in a stack frame can be located by understanding
how the stack frame is created. This process begins in the
main()
function,
even before the function call.
(gdb) disass main
Dump of assembler code for function main:
0x08048474 <main+0>: push ebp
0x08048475 <main+1>: mov ebp,esp
0x08048477 <main+3>: sub esp,0x8
0x0804847a <main+6>: and esp,0xfffffff0
0x0804847d <main+9>: mov eax,0x0
0x08048482 <main+14>: sub esp,eax
0x08048484 <main+16>: cmp DWORD PTR [ebp+8],0x1
0x08048488 <main+20>: jg 0x80484ab <main+55>
0x0804848a <main+22>: mov eax,DWORD PTR [ebp+12]
0x0804848d <main+25>: mov eax,DWORD PTR [eax]
0x0804848f <main+27>: mov DWORD PTR [esp+4],eax
0x08048493 <main+31>: mov DWORD PTR [esp],0x80485e5
0x0804849a <main+38>: call 0x804831c <printf@plt>
0x0804849f <main+43>: mov DWORD PTR [esp],0x0
0x080484a6 <main+50>: call 0x804833c <exit@plt>
0x080484ab <main+55>: mov eax,DWORD PTR [ebp+12]
0x080484ae <main+58>: add eax,0x4
0x080484b1 <main+61>: mov eax,DWORD PTR [eax]
0x080484b3 <main+63>: mov DWORD PTR [esp],eax
0x080484b6 <main+66>: call 0x8048414 <check_authentication>
0x080484bb <main+71>: test eax,eax
0x080484bd <main+73>: je 0x80484e5 <main+113>
0x080484bf <main+75>: mov DWORD PTR [esp],0x80485fb
0x080484c6 <main+82>: call 0x804831c <printf@plt>
0x080484cb <main+87>: mov DWORD PTR [esp],0x8048619
0x080484d2 <main+94>: call 0x804831c <printf@plt>
0x080484d7 <main+99>: mov DWORD PTR [esp],0x8048630
0x080484de <main+106>: call 0x804831c <printf@plt>
0x080484e3 <main+111>: jmp 0x80484f1 <main+125>
0x080484e5 <main+113>: mov DWORD PTR [esp],0x804864d
0x080484ec <main+120>: call 0x804831c <printf@plt>
0x080484f1 <main+125>: leave
0x080484f2 <main+126>: ret
End of assembler dump.
(
gdb)
