diff options
Diffstat (limited to 'sysdeps/unix/sysv/linux/i386/____longjmp_chk.S')
| -rw-r--r-- | sysdeps/unix/sysv/linux/i386/____longjmp_chk.S | 143 |
1 files changed, 143 insertions, 0 deletions
diff --git a/sysdeps/unix/sysv/linux/i386/____longjmp_chk.S b/sysdeps/unix/sysv/linux/i386/____longjmp_chk.S new file mode 100644 index 0000000000..02c401c236 --- /dev/null +++ b/sysdeps/unix/sysv/linux/i386/____longjmp_chk.S @@ -0,0 +1,143 @@ +/* Copyright (C) 2001,2004,2005,2006,2009 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> + + + .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; \ + cfi_register(%ebx,%ecx); \ + LOAD_PIC_REG (bx); \ + leal longjmp_msg@GOTOFF(%ebx), %eax; \ + call __GI___fortify_fail@PLT +#else +# define CALL_FAIL movl $longjmp_msg, %eax; \ + call __fortify_fail +#endif + +#define CHECK_ESP(reg) \ + cmpl reg, %esp; \ + jbe .Lok; \ + CALL_FAIL; \ +.Lok: + + + .text +ENTRY (____longjmp_chk) + movl 4(%esp), %ecx /* User's jmp_buf in %ecx. */ + + /* Save the return address now. */ + movl (JB_PC*4)(%ecx), %edx + /* Get the stack pointer. */ + movl (JB_SP*4)(%ecx), %edi + cfi_undefined(%edi) + PTR_DEMANGLE (%edx) + PTR_DEMANGLE (%edi) + + pushl $0 + cfi_adjust_cfa_offset(4) + cmpl %edi, %esp + jbe .Lok + + subl $12, %esp + cfi_adjust_cfa_offset(12) + xorl %ebx, %ebx + movl %esp, %ecx + movl $__NR_sigaltstack, %eax + ENTER_KERNEL + movl 4(%esp), %ebx + addl $12, %esp + cfi_adjust_cfa_offset(-12) + movl 8(%esp), %ecx + testl %eax, %eax + jne .Lok + andl $1, %ebx + movl %ebx, (%esp) +.Lok: + cfi_def_cfa(%ecx, 0) + cfi_register(%eip, %edx) + cfi_register(%esp, %edi) + cfi_offset(%ebx, JB_BX*4) + cfi_offset(%esi, JB_SI*4) + cfi_offset(%edi, JB_DI*4) + cfi_offset(%ebp, JB_BP*4) + + movl 12(%esp), %eax /* Second argument is return value. */ + xchgl %edi, %esp + cfi_restore(%edi) + + cmpl %esp, %edi + jnbe .Lcheck + + /* Restore registers. */ +.Lout: movl (JB_BX*4)(%ecx), %ebx + movl (JB_SI*4)(%ecx), %esi + movl (JB_DI*4)(%ecx), %edi + movl (JB_BP*4)(%ecx), %ebp + cfi_restore(%ebx) + cfi_restore(%esi) + cfi_restore(%edi) + cfi_restore(%ebp) + + /* Jump to saved PC. */ + jmp *%edx + + cfi_def_cfa(%ecx, 0) + cfi_register(%eip, %edx) + cfi_offset(%ebx, JB_BX*4) + cfi_offset(%esi, JB_SI*4) + cfi_offset(%edi, JB_DI*4) + cfi_offset(%ebp, JB_BP*4) + +.Lcheck: + cmpl $0, (%edi) + je .Lfail + + subl $12, %esp + cfi_adjust_cfa_offset(12) + xorl %ebx, %ebx + movl %esp, %ecx + movl $__NR_sigaltstack, %eax + ENTER_KERNEL + testl $1, 4(%esp) + leal 12(%esp), %esp + movl 8(%edi), %ecx + movl 12(%edi), %eax + cfi_adjust_cfa_offset(-12) + je .Lout + +.Lfail: xchgl %edi, %esp + cfi_def_cfa(%esp, 8) + cfi_restore(%esp) + cfi_restore(%ebx) + cfi_restore(%esi) + cfi_undefined(%edi) + cfi_restore(%ebp) + + CALL_FAIL + hlt +END (____longjmp_chk) |