mirror of
				https://sourceware.org/git/glibc.git
				synced 2025-11-03 20:53:13 +03:00 
			
		
		
		
	
		
			
				
	
	
		
			97 lines
		
	
	
		
			2.4 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			97 lines
		
	
	
		
			2.4 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
/* Check longjmp from user context to main context.
 | 
						|
   Copyright (C) 2023-2025 Free Software Foundation, Inc.
 | 
						|
   This file is part of the GNU C Library.
 | 
						|
 | 
						|
   The GNU C Library is free software; you can redistribute it and/or
 | 
						|
   modify it under the terms of the GNU Lesser General Public
 | 
						|
   License as published by the Free Software Foundation; either
 | 
						|
   version 2.1 of the License, or (at your option) any later version.
 | 
						|
 | 
						|
   The GNU C Library is distributed in the hope that it will be useful,
 | 
						|
   but WITHOUT ANY WARRANTY; without even the implied warranty of
 | 
						|
   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 | 
						|
   Lesser General Public License for more details.
 | 
						|
 | 
						|
   You should have received a copy of the GNU Lesser General Public
 | 
						|
   License along with the GNU C Library; if not, see
 | 
						|
   <https://www.gnu.org/licenses/>.  */
 | 
						|
 | 
						|
/* When _FORTIFY_SOURCE is defined to 2, ____longjmp_chk is called,
 | 
						|
   instead of longjmp.  ____longjmp_chk compares the relative stack
 | 
						|
   values to decide if it is called from a stack frame which called
 | 
						|
   setjmp.  If not, ____longjmp_chk assumes that an alternate signal
 | 
						|
   stack is used.  Since comparing the relative stack values isn't
 | 
						|
   reliable with user context, when there is no signal, ____longjmp_chk
 | 
						|
   will fail.  Undefine _FORTIFY_SOURCE to avoid ____longjmp_chk.  */
 | 
						|
#undef _FORTIFY_SOURCE
 | 
						|
 | 
						|
#include <stdio.h>
 | 
						|
#include <stdlib.h>
 | 
						|
#include <setjmp.h>
 | 
						|
#include <ucontext.h>
 | 
						|
#include <unistd.h>
 | 
						|
 | 
						|
static jmp_buf jmpbuf;
 | 
						|
static ucontext_t ctx;
 | 
						|
 | 
						|
static void f2 (void);
 | 
						|
 | 
						|
static void
 | 
						|
__attribute_optimization_barrier__
 | 
						|
f1 (void)
 | 
						|
{
 | 
						|
  printf ("start f1\n");
 | 
						|
  f2 ();
 | 
						|
}
 | 
						|
 | 
						|
static void
 | 
						|
__attribute_optimization_barrier__
 | 
						|
f2 (void)
 | 
						|
{
 | 
						|
  printf ("start f2\n");
 | 
						|
  if (setcontext (&ctx) != 0)
 | 
						|
    {
 | 
						|
      printf ("%s: setcontext: %m\n", __FUNCTION__);
 | 
						|
      exit (EXIT_FAILURE);
 | 
						|
    }
 | 
						|
}
 | 
						|
 | 
						|
static void
 | 
						|
f3 (void)
 | 
						|
{
 | 
						|
  printf ("start f3\n");
 | 
						|
  longjmp (jmpbuf, 1);
 | 
						|
}
 | 
						|
 | 
						|
static int
 | 
						|
__attribute_optimization_barrier__
 | 
						|
do_test_1 (void)
 | 
						|
{
 | 
						|
  char st1[32768];
 | 
						|
 | 
						|
  if (setjmp (jmpbuf) != 0)
 | 
						|
    return 0;
 | 
						|
 | 
						|
  puts ("making contexts");
 | 
						|
  if (getcontext (&ctx) != 0)
 | 
						|
    {
 | 
						|
      printf ("%s: getcontext: %m\n", __FUNCTION__);
 | 
						|
      exit (EXIT_FAILURE);
 | 
						|
    }
 | 
						|
  ctx.uc_stack.ss_sp = st1;
 | 
						|
  ctx.uc_stack.ss_size = sizeof st1;
 | 
						|
  ctx.uc_link = NULL;
 | 
						|
  makecontext (&ctx, (void (*) (void)) f3, 0);
 | 
						|
  f1 ();
 | 
						|
  puts ("FAIL: returned from f1 ()");
 | 
						|
  exit (EXIT_FAILURE);
 | 
						|
}
 | 
						|
 | 
						|
static int
 | 
						|
do_test (void)
 | 
						|
{
 | 
						|
  return do_test_1 ();
 | 
						|
}
 | 
						|
 | 
						|
#include <support/test-driver.c>
 |