1 /* 2 * Copyright (C) 2015 The Android Open Source Project 3 * All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions 7 * are met: 8 * * Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer. 10 * * Redistributions in binary form must reproduce the above copyright 11 * notice, this list of conditions and the following disclaimer in 12 * the documentation and/or other materials provided with the 13 * distribution. 14 * 15 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 16 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 17 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS 18 * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE 19 * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, 20 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, 21 * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS 22 * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED 23 * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, 24 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT 25 * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 26 * SUCH DAMAGE. 27 */ 28 29 #ifndef _PRIVATE_BIONIC_GLOBALS_H 30 #define _PRIVATE_BIONIC_GLOBALS_H 31 32 #include <inttypes.h> 33 #include <link.h> 34 #include <platform/bionic/malloc.h> 35 #include <pthread.h> 36 #include <stdatomic.h> 37 #include <sys/cdefs.h> 38 39 #include "private/WriteProtected.h" 40 #include "private/bionic_allocator.h" 41 #include "private/bionic_elf_tls.h" 42 #include "private/bionic_fdsan.h" 43 #include "private/bionic_malloc_dispatch.h" 44 #include "private/bionic_vdso.h" 45 46 struct libc_globals { 47 vdso_entry vdso[VDSO_END]; 48 long setjmp_cookie; 49 uintptr_t heap_pointer_tag; 50 _Atomic(bool) memtag_stack; 51 52 // In order to allow a complete switch between dispatch tables without 53 // the need for copying each function by function in the structure, 54 // use a single atomic pointer to switch. 55 // The current_dispatch_table pointer can only ever be set to a complete 56 // table. Any dispatch table that is pointed to by current_dispatch_table 57 // cannot be modified after that. If the pointer changes in the future, 58 // the old pointer must always stay valid. 59 // The malloc_dispatch_table is modified by malloc debug, malloc hooks, 60 // and heaprofd. Only one of these modes can be active at any given time. 61 _Atomic(const MallocDispatch*) current_dispatch_table; 62 // This pointer is only used by the allocation limit code when both a 63 // limit is enabled and some other hook is enabled at the same time. 64 _Atomic(const MallocDispatch*) default_dispatch_table; 65 MallocDispatch malloc_dispatch_table; 66 }; 67 68 __LIBC_HIDDEN__ extern WriteProtected<libc_globals> __libc_globals; 69 70 struct abort_msg_t; 71 namespace gwp_asan { 72 struct AllocatorState; 73 struct AllocationMetadata; 74 }; // namespace gwp_asan 75 76 // Globals shared between the dynamic linker and libc.so. 77 struct libc_shared_globals { 78 // Construct the shared globals using a constexpr constructor to ensure that 79 // the object doesn't need dynamic initialization. The object is accessed 80 // before the dynamic linker has relocated itself. libc_shared_globalslibc_shared_globals81 constexpr libc_shared_globals() {} 82 83 FdTable fd_table; 84 85 // When the linker is invoked on a binary (e.g. `linker64 /system/bin/date`), 86 // record the number of arguments passed to the linker itself rather than to 87 // the program it's loading. Typically 0, sometimes 1. 88 int initial_linker_arg_count = 0; 89 90 ElfW(auxv_t)* auxv = nullptr; 91 92 pthread_mutex_t abort_msg_lock = PTHREAD_MUTEX_INITIALIZER; 93 abort_msg_t* abort_msg = nullptr; 94 95 StaticTlsLayout static_tls_layout; 96 TlsModules tls_modules; 97 BionicAllocator tls_allocator; 98 99 // Values passed from libc.so to the loader. 100 void (*load_hook)(ElfW(Addr) base, const ElfW(Phdr)* phdr, ElfW(Half) phnum) = nullptr; 101 void (*unload_hook)(ElfW(Addr) base, const ElfW(Phdr)* phdr, ElfW(Half) phnum) = nullptr; 102 void (*set_target_sdk_version_hook)(int target) = nullptr; 103 104 // Values passed from the linker to libc.so. 105 const char* init_progname = nullptr; 106 char** init_environ = nullptr; 107 108 const gwp_asan::AllocatorState* gwp_asan_state = nullptr; 109 const gwp_asan::AllocationMetadata* gwp_asan_metadata = nullptr; 110 bool (*debuggerd_needs_gwp_asan_recovery)(void* fault_addr) = nullptr; 111 void (*debuggerd_gwp_asan_pre_crash_report)(void* fault_addr) = nullptr; 112 void (*debuggerd_gwp_asan_post_crash_report)(void* fault_addr) = nullptr; 113 114 const char* scudo_stack_depot = nullptr; 115 const char* scudo_region_info = nullptr; 116 const char* scudo_ring_buffer = nullptr; 117 size_t scudo_ring_buffer_size = 0; 118 119 HeapTaggingLevel initial_heap_tagging_level = M_HEAP_TAGGING_LEVEL_NONE; 120 bool initial_memtag_stack = false; 121 int64_t heap_tagging_upgrade_timer_sec = 0; 122 }; 123 124 __LIBC_HIDDEN__ libc_shared_globals* __libc_shared_globals(); 125 __LIBC_HIDDEN__ void __libc_init_fdsan(); 126 __LIBC_HIDDEN__ void __libc_init_fdtrack(); 127 __LIBC_HIDDEN__ void __libc_init_profiling_handlers(); 128 129 __LIBC_HIDDEN__ void __libc_init_malloc(libc_globals* globals); 130 __LIBC_HIDDEN__ void __libc_init_setjmp_cookie(libc_globals* globals); 131 __LIBC_HIDDEN__ void __libc_init_vdso(libc_globals* globals); 132 133 #if defined(__i386__) 134 __LIBC_HIDDEN__ extern void* __libc_sysinfo; 135 extern "C" __LIBC_HIDDEN__ void __libc_int0x80(); 136 __LIBC_HIDDEN__ void __libc_init_sysinfo(); 137 #endif 138 139 #endif 140