sys/libkern/stack_protector.c

   1 /*
   2  * Copyright (c) 2002 Hiroaki Etoh.
   3  * All rights reserved.
   4  *
   5  * Redistribution and use in source and binary forms, with or without
   6  * modification, are permitted provided that the following conditions
   7  * are met:
   8  * 1. Redistributions of source code must retain the above copyright
   9  *    notice, this list of conditions and the following disclaimer.
  10  * 2. Redistributions in binary form must reproduce the above copyright
  11  *    notice, this list of conditions and the following disclaimer in the
  12  *    documentation and/or other materials provided with the distribution.
  13  *
  14  * THIS SOFTWARE IS PROVIDED BY THE AUTHORS ``AS IS'' AND ANY EXPRESS OR
  15  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
  16  * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
  17  * DISCLAIMED.  IN NO EVENT SHALL THE AUTHORS BE LIABLE FOR ANY DIRECT,
  18  * INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
  19  * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
  20  * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  21  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
  22  * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
  23  * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
  24  * POSSIBILITY OF SUCH DAMAGE.
  25  *
  26  * $DragonFly: src/sys/libkern/stack_protector.c,v 1.5 2005/04/15 18:07:13 joerg Exp $
  27  */
  28
  29 #include <sys/param.h>
  30 #include <sys/endian.h>
  31
  32 void __stack_smash_handler(char[], int);
  33
  34 #if BYTE_ORDER == LITTLE_ENDIAN
  35 int __guard = 0x00000aff;
  36 #else
  37 int __guard = 0xff0a0000;
  38 #endif
  39
  40 void
  41 __stack_smash_handler(char func[], int damaged)
  42 {
  43 #ifdef __i386__
  44         void *caller;
  45         __asm __volatile("movl 4(%%ebp), %0" : "=r" (caller));
  46         panic("stack overflow in function %p (%s)", caller, func);
  47 #else
  48         panic("stack overflow in function %s", func);
  49 #endif
  50 }