1  /* Copyright (C) 2009-2023 Free Software Foundation, Inc.
       2     This file is part of the GNU C Library.
       3  
       4     The GNU C Library is free software; you can redistribute it and/or
       5     modify it under the terms of the GNU Lesser General Public
       6     License as published by the Free Software Foundation; either
       7     version 2.1 of the License, or (at your option) any later version.
       8  
       9     The GNU C Library is distributed in the hope that it will be useful,
      10     but WITHOUT ANY WARRANTY; without even the implied warranty of
      11     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
      12     Lesser General Public License for more details.
      13  
      14     You should have received a copy of the GNU General Public License
      15     along with GCC; see the file COPYING.  If not, write to the Free
      16     Software Foundation, 51 Franklin Street, Fifth Floor, Boston, MA
      17     02110-1301, USA.  */
      18  
      19  #include <stdio.h>
      20  #include <signal.h>
      21  #include <sysdep.h>
      22  #define __longjmp ____longjmp_chk
      23  #define CHECK_SP(sp)							\
      24    do {									\
      25      register unsigned long this_sp asm ("r30");				\
      26      /* The stack grows up, therefore frames that were created and then	\
      27         destroyed must all have stack values higher than ours.  */	\
      28      if ((unsigned long) (sp) > this_sp)					\
      29        {									\
      30          stack_t oss;							\
      31          int result = INTERNAL_SYSCALL_CALL (sigaltstack, NULL, &oss);\
      32  	/* If we aren't using an alternate stack then we have already	\
      33  	   shown that we are jumping to a frame that doesn't exist so	\
      34  	   error out. If we are using an alternate stack we must prove	\
      35  	   that we are jumping *out* of the alternate stack. Note that	\
      36  	   the check for that is the same as that for _STACK_GROWS_UP	\
      37  	   as for _STACK_GROWS_DOWN.  */				\
      38          if (!INTERNAL_SYSCALL_ERROR_P (result)				\
      39              && ((oss.ss_flags & SS_ONSTACK) == 0			\
      40                  || ((unsigned long) oss.ss_sp + oss.ss_size		\
      41                      - (unsigned long) (sp)) < oss.ss_size))		\
      42            __fortify_fail ("longjmp causes uninitialized stack frame");	\
      43        }									\
      44    } while (0)
      45  
      46  #include <__longjmp.c>