projects / thirdparty / glibc.git / blame
| Commit | Line | Data |
|---|---|---|
| d614a753 | 1 | /* Copyright (C) 2001-2020 Free Software Foundation, Inc. |
| bcf55240 TS |
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 | |
| 5a82c748 | 16 | <https://www.gnu.org/licenses/>. */ |
| bcf55240 TS |
17 | |
| 18 | #include <sysdep.h> | |
| 19 | #include <jmpbuf-offsets.h> | |
| 20 | #include <asm-syntax.h> | |
| 21 | ||
| 22 | #include <signal-defines.h> | |
| 23 | /* #include <signal.h> */ | |
| 24 | #define SS_ONSTACK 1 | |
| 25 | ||
| 26 | ||
| 27 | .section .rodata.str1.1,"aMS",@progbits,1 | |
| 28 | .type longjmp_msg,@object | |
| 29 | longjmp_msg: | |
| 30 | .string "longjmp causes uninitialized stack frame" | |
| 31 | .size longjmp_msg, .-longjmp_msg | |
| 32 | ||
| 33 | ||
| 34 | #ifdef PIC | |
| 35 | # define CALL_FAIL movl %ebx, %ecx; /* TODO: what's this mov good for? */ \ | |
| 36 | cfi_register(%ebx,%ecx); \ | |
| 37 | LOAD_PIC_REG (bx); \ | |
| 38 | leal longjmp_msg@GOTOFF(%ebx), %eax; \ | |
| 1b0bfc69 | 39 | movl %eax, (%esp); \ |
| bcf55240 TS |
40 | call HIDDEN_JUMPTARGET(__fortify_fail) |
| 41 | #else | |
| 42 | # define CALL_FAIL movl $longjmp_msg, %eax; \ | |
| 1b0bfc69 | 43 | movl %eax, (%esp); \ |
| bcf55240 TS |
44 | call HIDDEN_JUMPTARGET(__fortify_fail) |
| 45 | #endif | |
| 46 | ||
| 47 | ||
| 48 | .text | |
| 49 | ENTRY (____longjmp_chk) | |
| 50 | movl 4(%esp), %ecx /* User's jmp_buf in %ecx. */ | |
| 51 | ||
| 52 | /* Save the return address now. */ | |
| 53 | movl (JB_PC*4)(%ecx), %edx | |
| 54 | /* Get the stack pointer. */ | |
| 55 | movl (JB_SP*4)(%ecx), %edi | |
| 56 | cfi_undefined(%edi) | |
| e10bb107 | 57 | #ifdef PTR_DEMANGLE |
| bcf55240 TS |
58 | PTR_DEMANGLE (%edx) |
| 59 | PTR_DEMANGLE (%edi) | |
| e10bb107 | 60 | #endif |
| bcf55240 TS |
61 | |
| 62 | cmpl %edi, %esp | |
| 63 | /* Jumping to a higher-address frame is always allowed. */ | |
| 64 | jbe .Lok | |
| 65 | ||
| 66 | /* Passing here, we're either about to do something invalid, or we're | |
| 67 | executing on an alternative signal stack. */ | |
| 68 | ||
| 69 | /* TODO: need locking? */ | |
| 70 | /* struct hurd_sigstate * _hurd_self_sigstate (void) */ | |
| 4d0ac037 | 71 | call HIDDEN_JUMPTARGET(_hurd_self_sigstate) |
| bcf55240 TS |
72 | /* TODO: %eax and %eax->sigaltstack are always valid? */ |
| 73 | ||
| 74 | testl $SS_ONSTACK, (HURD_SIGSTATE__SIGALTSTACK__OFFSET + SIGALTSTACK__SS_FLAGS__OFFSET)(%eax) | |
| 75 | /* Fail if SS_ONSTACK is not set. */ | |
| 76 | jz .Lfail | |
| 77 | ||
| 78 | movl (HURD_SIGSTATE__SIGALTSTACK__OFFSET + SIGALTSTACK__SS_SP__OFFSET)(%eax), %ebx | |
| 79 | addl (HURD_SIGSTATE__SIGALTSTACK__OFFSET + SIGALTSTACK__SS_SIZE__OFFSET)(%eax), %ebx | |
| 80 | subl %edi, %ebx | |
| 81 | cmpl (HURD_SIGSTATE__SIGALTSTACK__OFFSET + SIGALTSTACK__SS_SIZE__OFFSET)(%eax), %ebx | |
| 82 | /* TODO: comment this calculation. */ | |
| 83 | jae .Lok | |
| 84 | ||
| 85 | .Lfail: CALL_FAIL | |
| 86 | ||
| 87 | .Lok: /* We add unwind information for the target here. */ | |
| 88 | cfi_def_cfa(%ecx, 0) | |
| 89 | cfi_register(%eip, %edx) | |
| 90 | cfi_register(%esp, %edi) | |
| 91 | cfi_offset(%ebx, JB_BX*4) | |
| 92 | cfi_offset(%esi, JB_SI*4) | |
| 93 | cfi_offset(%edi, JB_DI*4) | |
| 94 | cfi_offset(%ebp, JB_BP*4) | |
| 95 | ||
| 96 | movl 8(%esp), %eax /* Second argument is return value. */ | |
| 97 | movl %edi, %esp | |
| 98 | ||
| 99 | /* Restore registers. */ | |
| 100 | movl (JB_BX*4)(%ecx), %ebx | |
| 101 | movl (JB_SI*4)(%ecx), %esi | |
| 102 | movl (JB_DI*4)(%ecx), %edi | |
| 103 | movl (JB_BP*4)(%ecx), %ebp | |
| 104 | cfi_restore(%ebx) | |
| 105 | cfi_restore(%esi) | |
| 106 | cfi_restore(%edi) | |
| 107 | cfi_restore(%ebp) | |
| 108 | ||
| 109 | /* Jump to saved PC. */ | |
| 110 | jmp *%edx | |
| 111 | END (____longjmp_chk) |