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_common.h" 20 #include "sanitizer_common/sanitizer_internal_defs.h" 21 22 namespace __hwasan { 23 // This object should only ever be casted over the global (i.e. not constructed) 24 // in the ELF PT_NOTE in order for `addr()` to work correctly. 25 struct hwasan_global { 26 // The size of this global variable. Note that the size in the descriptor is 27 // max 1 << 24. Larger globals have multiple descriptors. 28 uptr size() const { return info & 0xffffff; } 29 // The fully-relocated address of this global. 30 uptr addr() const { return reinterpret_cast<uintptr_t>(this) + gv_relptr; } 31 // The static tag of this global. 32 u8 tag() const { return info >> 24; }; 33 34 // The relative address between the start of the descriptor for the HWASan 35 // global (in the PT_NOTE), and the fully relocated address of the global. 36 s32 gv_relptr; 37 u32 info; 38 }; 39 40 // Walk through the specific DSO (as specified by the base, phdr, and phnum), 41 // and return the range of the [beginning, end) of the HWASan globals descriptor 42 // array. 43 ArrayRef<const hwasan_global> HwasanGlobalsFor(ElfW(Addr) base, 44 const ElfW(Phdr) * phdr, 45 ElfW(Half) phnum); 46 47 } // namespace __hwasan 48 49 #endif // HWASAN_GLOBALS_H 50