1//===-- hwasan_globals.h ----------------------------------------*- C++ -*-===//
2//
3// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4// See https://llvm.org/LICENSE.txt for license information.
5// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6//
7//===----------------------------------------------------------------------===//
8//
9// This file is a part of HWAddressSanitizer.
10//
11// Private Hwasan header.
12//===----------------------------------------------------------------------===//
13
14#ifndef HWASAN_GLOBALS_H
15#define HWASAN_GLOBALS_H
16
17#include <link.h>
18
19#include "sanitizer_common/sanitizer_array_ref.h"
20#include "sanitizer_common/sanitizer_common.h"
21#include "sanitizer_common/sanitizer_internal_defs.h"
22
23namespace __hwasan {
24// This object should only ever be casted over the global (i.e. not constructed)
25// in the ELF PT_NOTE in order for `addr()` to work correctly.
26struct hwasan_global {
27 // The size of this global variable. Note that the size in the descriptor is
28 // max 1 << 24. Larger globals have multiple descriptors.
29 uptr size() const { return info & 0xffffff; }
30 // The fully-relocated address of this global.
31 uptr addr() const { return reinterpret_cast<uintptr_t>(this) + gv_relptr; }
32 // The static tag of this global.
33 u8 tag() const { return info >> 24; };
34
35 // The relative address between the start of the descriptor for the HWASan
36 // global (in the PT_NOTE), and the fully relocated address of the global.
37 s32 gv_relptr;
38 u32 info;
39};
40
41// Walk through the specific DSO (as specified by the base, phdr, and phnum),
42// and return the range of the [beginning, end) of the HWASan globals descriptor
43// array.
44ArrayRef<const hwasan_global> HwasanGlobalsFor(ElfW(Addr) base,
45 const ElfW(Phdr) * phdr,
46 ElfW(Half) phnum);
47
48} // namespace __hwasan
49
50#endif // HWASAN_GLOBALS_H
51