glibc/sysdeps/i386/__longjmp.S
Ulrich Drepper b50f8e42ba Check for valid stack frame in longjmp.
If longjmp restores the stack frame to an address which is beyond
the stack frame at the time of the longjmp call it would install
an uninitialized stack frame.  If compiled with _FORTIFY_SOURCE
defined, longjmp will now bail out in this situation.
2009-05-15 19:37:13 -07:00

88 lines
2.5 KiB
ArmAsm

/* longjmp for i386.
Copyright (C) 1995-1998,2000,2002,2005,2006,2009
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, write to the Free
Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
02111-1307 USA. */
#include <sysdep.h>
#include <jmpbuf-offsets.h>
#include <asm-syntax.h>
#include <bp-sym.h>
#include <bp-asm.h>
#define PARMS LINKAGE /* no space for saved regs */
#define JBUF PARMS
#define VAL JBUF+PTR_SIZE
ENTRY (BP_SYM (__longjmp))
ENTER
#ifdef PTR_DEMANGLE
movl JBUF(%esp), %eax /* User's jmp_buf in %eax. */
CHECK_BOUNDS_BOTH_WIDE (%eax, JBUF(%esp), $JB_SIZE)
/* Save the return address now. */
movl (JB_PC*4)(%eax), %edx
/* Get the stack pointer. */
movl (JB_SP*4)(%eax), %ecx
PTR_DEMANGLE (%edx)
PTR_DEMANGLE (%ecx)
# ifdef CHECK_ESP
CHECK_ESP (%ecx)
# endif
cfi_def_cfa(%eax, 0)
cfi_register(%eip, %edx)
cfi_register(%esp, %ecx)
cfi_offset(%ebx, JB_BX*4)
cfi_offset(%esi, JB_SI*4)
cfi_offset(%edi, JB_DI*4)
cfi_offset(%ebp, JB_BP*4)
/* Restore registers. */
movl (JB_BX*4)(%eax), %ebx
movl (JB_SI*4)(%eax), %esi
movl (JB_DI*4)(%eax), %edi
movl (JB_BP*4)(%eax), %ebp
cfi_restore(%ebx)
cfi_restore(%esi)
cfi_restore(%edi)
cfi_restore(%ebp)
movl VAL(%esp), %eax /* Second argument is return value. */
movl %ecx, %esp
#else
movl JBUF(%esp), %ecx /* User's jmp_buf in %ecx. */
CHECK_BOUNDS_BOTH_WIDE (%ecx, JBUF(%esp), $JB_SIZE)
# ifdef CHECK_ESP
movl (JB_SP*4)(%ecx), %eax
CHECK_ESP (%eax)
# endif
movl VAL(%esp), %eax /* Second argument is return value. */
/* Save the return address now. */
movl (JB_PC*4)(%ecx), %edx
/* Restore registers. */
movl (JB_BX*4)(%ecx), %ebx
movl (JB_SI*4)(%ecx), %esi
movl (JB_DI*4)(%ecx), %edi
movl (JB_BP*4)(%ecx), %ebp
movl (JB_SP*4)(%ecx), %esp
#endif
/* Jump to saved PC. */
jmp *%edx
END (BP_SYM (__longjmp))