blob: ef3d68ccb4f9b059c4dc3872500a652fd03e2cef [file] [log] [blame]
// Copyright 2018 The Crashpad Authors. All rights reserved.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
// This note section is used on ELF platforms to give ElfImageReader a method
// of finding the instance of CrashpadInfo g_crashpad_info without requiring
// that symbol to be in the dynamic symbol table.
#include "util/misc/elf_note_types.h"
#include "util/misc/arm64_bti_note.S"
// namespace crashpad {
// CrashpadInfo g_crashpad_info;
// } // namespace crashpad
#define CRASHPAD_INFO_SYMBOL _ZN8crashpad15g_crashpad_infoE
#define NOTE_ALIGN 4
// This section must be "a"llocated so that it appears in the final binary at
// runtime. The reference to CRASHPAD_INFO_SYMBOL uses an offset relative to
// this note to avoid making this note writable, which triggers a bug in GNU
// ld, or adding text relocations which require the target system to allow
// making text segments writable. https://crbug.com/crashpad/260.
.section .note.crashpad.info,"a",%note
.balign NOTE_ALIGN
CRASHPAD_NOTE:
.long name_end - name // namesz
.long desc_end - desc // descsz
.long CRASHPAD_ELF_NOTE_TYPE_CRASHPAD_INFO // type
name:
.asciz CRASHPAD_ELF_NOTE_NAME
name_end:
.balign NOTE_ALIGN
desc:
#if defined(__LP64__)
.quad CRASHPAD_INFO_SYMBOL - desc
#else
.long CRASHPAD_INFO_SYMBOL - desc
#endif // __LP64__
desc_end:
.size CRASHPAD_NOTE, .-CRASHPAD_NOTE
// CRASHPAD_NOTE can't be referenced directly by GetCrashpadInfo() because the
// relocation used to make the reference may require that the address be
// 8-byte aligned and notes must have 4-byte alignment.
.section .rodata,"a",%progbits
.balign 8
# .globl indicates that it's available to link against other .o files. .hidden
# indicates that it will not appear in the executable's symbol table.
.globl CRASHPAD_NOTE_REFERENCE
.hidden CRASHPAD_NOTE_REFERENCE
.type CRASHPAD_NOTE_REFERENCE, %object
CRASHPAD_NOTE_REFERENCE:
// The value of this quad isn't important. It exists to reference
// CRASHPAD_NOTE, causing the linker to include the note into the binary
// linking Crashpad. The subtraction from |name| is a convenience to allow the
// value to be computed statically.
.quad name - CRASHPAD_NOTE