mirror of
https://sourceware.org/git/glibc.git
synced 2024-11-29 16:21:07 +00:00
88f4b6929c
This allows us to define a generic no-op version of PTR_MANGLE and PTR_DEMANGLE. In the future, we can use PTR_MANGLE and PTR_DEMANGLE unconditionally in C sources, avoiding an unintended loss of hardening due to missing include files or unlucky header inclusion ordering. In i386 and x86_64, we can avoid a <tls.h> dependency in the C code by using the computed constant from <tcb-offsets.h>. <sysdep.h> no longer includes these definitions, so there is no cyclic dependency anymore when computing the <tcb-offsets.h> constants. Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
126 lines
3.6 KiB
ArmAsm
126 lines
3.6 KiB
ArmAsm
/* Copyright (C) 2001-2022 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/>. */
|
|
|
|
#include <sysdep.h>
|
|
#include <pointer_guard.h>
|
|
#include <jmpbuf-offsets.h>
|
|
#include <tcb-offsets.h>
|
|
#include <asm-syntax.h>
|
|
|
|
#include <signal-defines.h>
|
|
/* #include <signal.h> */
|
|
#define SS_ONSTACK 1
|
|
|
|
|
|
.section .rodata.str1.1,"aMS",@progbits,1
|
|
.type longjmp_msg,@object
|
|
longjmp_msg:
|
|
.string "longjmp causes uninitialized stack frame"
|
|
.size longjmp_msg, .-longjmp_msg
|
|
|
|
|
|
#ifdef PIC
|
|
# define CALL_FAIL movl %ebx, %ecx; /* TODO: what's this mov good for? */ \
|
|
cfi_register(%ebx,%ecx); \
|
|
LOAD_PIC_REG (bx); \
|
|
leal longjmp_msg@GOTOFF(%ebx), %eax; \
|
|
movl %eax, (%esp); \
|
|
call HIDDEN_JUMPTARGET(__fortify_fail)
|
|
#else
|
|
# define CALL_FAIL movl $longjmp_msg, %eax; \
|
|
movl %eax, (%esp); \
|
|
call HIDDEN_JUMPTARGET(__fortify_fail)
|
|
#endif
|
|
|
|
|
|
.text
|
|
ENTRY (____longjmp_chk)
|
|
movl 4(%esp), %eax /* User's jmp_buf in %eax. */
|
|
|
|
/* Save the return address now. */
|
|
movl (JB_PC*4)(%eax), %edx
|
|
/* Get the stack pointer. */
|
|
movl (JB_SP*4)(%eax), %ecx
|
|
cfi_undefined(%ecx)
|
|
#ifdef PTR_DEMANGLE
|
|
PTR_DEMANGLE (%edx)
|
|
PTR_DEMANGLE (%ecx)
|
|
#endif
|
|
|
|
movw %ds, %si
|
|
movw %gs, %di
|
|
cmpw %si, %di
|
|
jz .Lok /* TLS not initialized yet */
|
|
|
|
movl %gs:SIGSTATE_OFFSET, %edi
|
|
testl %edi, %edi
|
|
jz .Lok /* sigstate not initialized yet */
|
|
|
|
testl $SS_ONSTACK, (HURD_SIGSTATE__SIGALTSTACK__OFFSET + SIGALTSTACK__SS_FLAGS__OFFSET)(%edi)
|
|
jnz .Lonstack
|
|
|
|
/* We were on the main stack */
|
|
|
|
cmpl %ecx, %esp
|
|
/* Jumping to a higher-address frame is always allowed. */
|
|
jbe .Lok
|
|
|
|
/* Otherwise it's not allowed. */
|
|
CALL_FAIL
|
|
|
|
.Lonstack:
|
|
/* We were on the alternate stack, can't really easily check anything
|
|
since longjmp may get us out of the alternate stack. */
|
|
|
|
cmpl (HURD_SIGSTATE__SIGALTSTACK__OFFSET + SIGALTSTACK__SS_SP__OFFSET)(%edi), %ecx
|
|
jb .Loks /* We jump below the alternate stack, switch. */
|
|
|
|
movl (HURD_SIGSTATE__SIGALTSTACK__OFFSET + SIGALTSTACK__SS_SP__OFFSET)(%edi), %ebx
|
|
addl (HURD_SIGSTATE__SIGALTSTACK__OFFSET + SIGALTSTACK__SS_SIZE__OFFSET)(%edi), %ebx
|
|
cmpl %ebx, %ecx
|
|
jb .Lok /* We jump inside the alternate stack, do not switch. */
|
|
|
|
/* We jump above the alternate stack, switch. */
|
|
|
|
.Loks: /* We jump out of the alternate stack, clear SS_ONSTACK flag. */
|
|
andl $~(SS_ONSTACK), (HURD_SIGSTATE__SIGALTSTACK__OFFSET + SIGALTSTACK__SS_FLAGS__OFFSET)(%edi)
|
|
|
|
.Lok: /* We add unwind information for the target here. */
|
|
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 8(%esp), %eax /* Second argument is return value. */
|
|
movl %ecx, %esp
|
|
|
|
/* Jump to saved PC. */
|
|
jmp *%edx
|
|
END (____longjmp_chk)
|