| //===-- sanitizer_procmaps_mac.cc -----------------------------------------===// |
| // |
| // The LLVM Compiler Infrastructure |
| // |
| // This file is distributed under the University of Illinois Open Source |
| // License. See LICENSE.TXT for details. |
| // |
| //===----------------------------------------------------------------------===// |
| // |
| // Information about the process mappings (Mac-specific parts). |
| //===----------------------------------------------------------------------===// |
| |
| #include "sanitizer_platform.h" |
| #if SANITIZER_MAC |
| #include "sanitizer_common.h" |
| #include "sanitizer_placement_new.h" |
| #include "sanitizer_procmaps.h" |
| |
| #include <mach-o/dyld.h> |
| #include <mach-o/loader.h> |
| |
| // These are not available in older macOS SDKs. |
| #ifndef CPU_SUBTYPE_X86_64_H |
| #define CPU_SUBTYPE_X86_64_H ((cpu_subtype_t)8) /* Haswell */ |
| #endif |
| #ifndef CPU_SUBTYPE_ARM_V7S |
| #define CPU_SUBTYPE_ARM_V7S ((cpu_subtype_t)11) /* Swift */ |
| #endif |
| #ifndef CPU_SUBTYPE_ARM_V7K |
| #define CPU_SUBTYPE_ARM_V7K ((cpu_subtype_t)12) |
| #endif |
| #ifndef CPU_TYPE_ARM64 |
| #define CPU_TYPE_ARM64 (CPU_TYPE_ARM | CPU_ARCH_ABI64) |
| #endif |
| |
| namespace __sanitizer { |
| |
| MemoryMappingLayout::MemoryMappingLayout(bool cache_enabled) { |
| Reset(); |
| } |
| |
| MemoryMappingLayout::~MemoryMappingLayout() { |
| } |
| |
| // More information about Mach-O headers can be found in mach-o/loader.h |
| // Each Mach-O image has a header (mach_header or mach_header_64) starting with |
| // a magic number, and a list of linker load commands directly following the |
| // header. |
| // A load command is at least two 32-bit words: the command type and the |
| // command size in bytes. We're interested only in segment load commands |
| // (LC_SEGMENT and LC_SEGMENT_64), which tell that a part of the file is mapped |
| // into the task's address space. |
| // The |vmaddr|, |vmsize| and |fileoff| fields of segment_command or |
| // segment_command_64 correspond to the memory address, memory size and the |
| // file offset of the current memory segment. |
| // Because these fields are taken from the images as is, one needs to add |
| // _dyld_get_image_vmaddr_slide() to get the actual addresses at runtime. |
| |
| void MemoryMappingLayout::Reset() { |
| // Count down from the top. |
| // TODO(glider): as per man 3 dyld, iterating over the headers with |
| // _dyld_image_count is thread-unsafe. We need to register callbacks for |
| // adding and removing images which will invalidate the MemoryMappingLayout |
| // state. |
| current_image_ = _dyld_image_count(); |
| current_load_cmd_count_ = -1; |
| current_load_cmd_addr_ = 0; |
| current_magic_ = 0; |
| current_filetype_ = 0; |
| current_arch_ = kModuleArchUnknown; |
| internal_memset(current_uuid_, 0, kModuleUUIDSize); |
| } |
| |
| // static |
| void MemoryMappingLayout::CacheMemoryMappings() { |
| // No-op on Mac for now. |
| } |
| |
| void MemoryMappingLayout::LoadFromCache() { |
| // No-op on Mac for now. |
| } |
| |
| // Next and NextSegmentLoad were inspired by base/sysinfo.cc in |
| // Google Perftools, https://github.com/gperftools/gperftools. |
| |
| // NextSegmentLoad scans the current image for the next segment load command |
| // and returns the start and end addresses and file offset of the corresponding |
| // segment. |
| // Note that the segment addresses are not necessarily sorted. |
| template <u32 kLCSegment, typename SegmentCommand> |
| bool MemoryMappingLayout::NextSegmentLoad(uptr *start, uptr *end, uptr *offset, |
| char filename[], uptr filename_size, |
| ModuleArch *arch, u8 *uuid, |
| uptr *protection) { |
| const char *lc = current_load_cmd_addr_; |
| current_load_cmd_addr_ += ((const load_command *)lc)->cmdsize; |
| if (((const load_command *)lc)->cmd == kLCSegment) { |
| const sptr dlloff = _dyld_get_image_vmaddr_slide(current_image_); |
| const SegmentCommand* sc = (const SegmentCommand *)lc; |
| if (start) *start = sc->vmaddr + dlloff; |
| if (protection) { |
| // Return the initial protection. |
| *protection = sc->initprot; |
| } |
| if (end) *end = sc->vmaddr + sc->vmsize + dlloff; |
| if (offset) { |
| if (current_filetype_ == /*MH_EXECUTE*/ 0x2) { |
| *offset = sc->vmaddr; |
| } else { |
| *offset = sc->fileoff; |
| } |
| } |
| if (filename) { |
| internal_strncpy(filename, _dyld_get_image_name(current_image_), |
| filename_size); |
| } |
| if (arch) { |
| *arch = current_arch_; |
| } |
| if (uuid) { |
| internal_memcpy(uuid, current_uuid_, kModuleUUIDSize); |
| } |
| return true; |
| } |
| return false; |
| } |
| |
| ModuleArch ModuleArchFromCpuType(cpu_type_t cputype, cpu_subtype_t cpusubtype) { |
| cpusubtype = cpusubtype & ~CPU_SUBTYPE_MASK; |
| switch (cputype) { |
| case CPU_TYPE_I386: |
| return kModuleArchI386; |
| case CPU_TYPE_X86_64: |
| if (cpusubtype == CPU_SUBTYPE_X86_64_ALL) return kModuleArchX86_64; |
| if (cpusubtype == CPU_SUBTYPE_X86_64_H) return kModuleArchX86_64H; |
| CHECK(0 && "Invalid subtype of x86_64"); |
| return kModuleArchUnknown; |
| case CPU_TYPE_ARM: |
| if (cpusubtype == CPU_SUBTYPE_ARM_V6) return kModuleArchARMV6; |
| if (cpusubtype == CPU_SUBTYPE_ARM_V7) return kModuleArchARMV7; |
| if (cpusubtype == CPU_SUBTYPE_ARM_V7S) return kModuleArchARMV7S; |
| if (cpusubtype == CPU_SUBTYPE_ARM_V7K) return kModuleArchARMV7K; |
| CHECK(0 && "Invalid subtype of ARM"); |
| return kModuleArchUnknown; |
| case CPU_TYPE_ARM64: |
| return kModuleArchARM64; |
| default: |
| CHECK(0 && "Invalid CPU type"); |
| return kModuleArchUnknown; |
| } |
| } |
| |
| static const load_command *NextCommand(const load_command *lc) { |
| return (const load_command *)((char *)lc + lc->cmdsize); |
| } |
| |
| static void FindUUID(const load_command *first_lc, u8 *uuid_output) { |
| for (const load_command *lc = first_lc; lc->cmd != 0; lc = NextCommand(lc)) { |
| if (lc->cmd != LC_UUID) continue; |
| |
| const uuid_command *uuid_lc = (const uuid_command *)lc; |
| const uint8_t *uuid = &uuid_lc->uuid[0]; |
| internal_memcpy(uuid_output, uuid, kModuleUUIDSize); |
| return; |
| } |
| } |
| |
| static bool IsModuleInstrumented(const load_command *first_lc) { |
| for (const load_command *lc = first_lc; lc->cmd != 0; lc = NextCommand(lc)) { |
| if (lc->cmd != LC_LOAD_DYLIB) continue; |
| |
| const dylib_command *dylib_lc = (const dylib_command *)lc; |
| uint32_t dylib_name_offset = dylib_lc->dylib.name.offset; |
| const char *dylib_name = ((const char *)dylib_lc) + dylib_name_offset; |
| dylib_name = StripModuleName(dylib_name); |
| if (dylib_name != 0 && (internal_strstr(dylib_name, "libclang_rt."))) { |
| return true; |
| } |
| } |
| return false; |
| } |
| |
| bool MemoryMappingLayout::Next(uptr *start, uptr *end, uptr *offset, |
| char filename[], uptr filename_size, |
| uptr *protection, ModuleArch *arch, u8 *uuid) { |
| for (; current_image_ >= 0; current_image_--) { |
| const mach_header* hdr = _dyld_get_image_header(current_image_); |
| if (!hdr) continue; |
| if (current_load_cmd_count_ < 0) { |
| // Set up for this image; |
| current_load_cmd_count_ = hdr->ncmds; |
| current_magic_ = hdr->magic; |
| current_filetype_ = hdr->filetype; |
| current_arch_ = ModuleArchFromCpuType(hdr->cputype, hdr->cpusubtype); |
| switch (current_magic_) { |
| #ifdef MH_MAGIC_64 |
| case MH_MAGIC_64: { |
| current_load_cmd_addr_ = (char*)hdr + sizeof(mach_header_64); |
| break; |
| } |
| #endif |
| case MH_MAGIC: { |
| current_load_cmd_addr_ = (char*)hdr + sizeof(mach_header); |
| break; |
| } |
| default: { |
| continue; |
| } |
| } |
| FindUUID((const load_command *)current_load_cmd_addr_, ¤t_uuid_[0]); |
| current_instrumented_ = |
| IsModuleInstrumented((const load_command *)current_load_cmd_addr_); |
| } |
| |
| for (; current_load_cmd_count_ >= 0; current_load_cmd_count_--) { |
| switch (current_magic_) { |
| // current_magic_ may be only one of MH_MAGIC, MH_MAGIC_64. |
| #ifdef MH_MAGIC_64 |
| case MH_MAGIC_64: { |
| if (NextSegmentLoad<LC_SEGMENT_64, struct segment_command_64>( |
| start, end, offset, filename, filename_size, arch, uuid, |
| protection)) |
| return true; |
| break; |
| } |
| #endif |
| case MH_MAGIC: { |
| if (NextSegmentLoad<LC_SEGMENT, struct segment_command>( |
| start, end, offset, filename, filename_size, arch, uuid, |
| protection)) |
| return true; |
| break; |
| } |
| } |
| } |
| // If we get here, no more load_cmd's in this image talk about |
| // segments. Go on to the next image. |
| } |
| return false; |
| } |
| |
| void MemoryMappingLayout::DumpListOfModules( |
| InternalMmapVector<LoadedModule> *modules) { |
| Reset(); |
| uptr cur_beg, cur_end, prot; |
| ModuleArch cur_arch; |
| u8 cur_uuid[kModuleUUIDSize]; |
| InternalScopedString module_name(kMaxPathLength); |
| for (uptr i = 0; Next(&cur_beg, &cur_end, 0, module_name.data(), |
| module_name.size(), &prot, &cur_arch, &cur_uuid[0]); |
| i++) { |
| const char *cur_name = module_name.data(); |
| if (cur_name[0] == '\0') |
| continue; |
| LoadedModule *cur_module = nullptr; |
| if (!modules->empty() && |
| 0 == internal_strcmp(cur_name, modules->back().full_name())) { |
| cur_module = &modules->back(); |
| } else { |
| modules->push_back(LoadedModule()); |
| cur_module = &modules->back(); |
| cur_module->set(cur_name, cur_beg, cur_arch, cur_uuid, |
| current_instrumented_); |
| } |
| cur_module->addAddressRange(cur_beg, cur_end, prot & kProtectionExecute); |
| } |
| } |
| |
| } // namespace __sanitizer |
| |
| #endif // SANITIZER_MAC |