sysdeps/unix/sysv/linux/powerpc/powerpc32/____longjmp_chk.S

   1 /* Copyright (C) 2009-2024 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 Lesser General Public
  15    License along with the GNU C Library; if not, see
  16    <https://www.gnu.org/licenses/>.  */
  17
  18 #include <sysdep.h>
  19 #include <rtld-global-offsets.h>
  20
  21         .section .rodata.str1.4,"aMS",@progbits,1
  22         .align 2
  23 .LC0:
  24         .string "longjmp causes uninitialized stack frame"
  25         .text
  26
  27 #define __longjmp_symbol ____longjmp_chk
  28
  29 #ifdef PIC
  30 #  define LOAD_ARG \
  31         SETUP_GOT_ACCESS(r3,got_label2);                        \
  32         addis   r3,r3,_GLOBAL_OFFSET_TABLE_-got_label2@ha;      \
  33         addi    r3,r3,_GLOBAL_OFFSET_TABLE_-got_label2@l;       \
  34         lwz     r3,.LC0@got(r3)
  35 #else
  36 # define LOAD_ARG \
  37         lis     r3,.LC0@ha;                             \
  38         la      r3,.LC0@l(r3)
  39 #endif
  40
  41 #define CHECK_SP(reg) \
  42         cmplw   reg, r1;                                \
  43         bge+    .Lok;                                   \
  44         mflr    r0;                                     \
  45         stwu    r1,-32(r1);                             \
  46         cfi_remember_state;                             \
  47         cfi_adjust_cfa_offset (32);                     \
  48         stw     r0,36(r1);                              \
  49         cfi_offset (lr, 4);                             \
  50         mr      r31,r3;                                 \
  51         mr      r30,r4;                                 \
  52         li      r3,0;                                   \
  53         addi    r4,r1,8;                                \
  54         li      r0,__NR_sigaltstack;                    \
  55         sc;                                             \
  56         /* Without working sigaltstack we cannot perform the test.  */ \
  57         bso     .Lok2;                                  \
  58         lwz     r0,12(r1);                              \
  59         andi.   r3,r0,1;                                \
  60         beq     .Lfail;                                 \
  61         lwz     r0,16(r1);                              \
  62         lwz     r3,8(r1);                               \
  63         add     r3,r3,r0;                               \
  64         sub     r3,r3,reg;                              \
  65         cmplw   r3,r0;                                  \
  66         bge+    .Lok2;                                  \
  67 .Lfail:                                                 \
  68         LOAD_ARG;                                       \
  69         bl      HIDDEN_JUMPTARGET (__fortify_fail);     \
  70 .Lok2:                                                  \
  71         mr      r3,r31;                                 \
  72         mr      r4,r30;                                 \
  73         cfi_restore_state;                              \
  74 .Lok:
  75
  76 #include <__longjmp-common.S>