1 //=-- lsan_common_mac.cc --------------------------------------------------===//
3 // This file is distributed under the University of Illinois Open Source
4 // License. See LICENSE.TXT for details.
6 //===----------------------------------------------------------------------===//
8 // This file is a part of LeakSanitizer.
9 // Implementation of common leak checking functionality. Darwin-specific code.
11 //===----------------------------------------------------------------------===//
13 #include "sanitizer_common/sanitizer_platform.h"
14 #include "lsan_common.h"
16 #if CAN_SANITIZE_LEAKS && SANITIZER_MAC
18 #include "sanitizer_common/sanitizer_allocator_internal.h"
19 #include "lsan_allocator.h"
23 #include <mach/mach.h>
25 // Only introduced in Mac OS X 10.9.
26 #ifdef VM_MEMORY_OS_ALLOC_ONCE
27 static const int kSanitizerVmMemoryOsAllocOnce
= VM_MEMORY_OS_ALLOC_ONCE
;
29 static const int kSanitizerVmMemoryOsAllocOnce
= 73;
36 u32 current_thread_id
;
38 } thread_local_data_t
;
40 static pthread_key_t key
;
41 static pthread_once_t key_once
= PTHREAD_ONCE_INIT
;
43 // The main thread destructor requires the current thread id,
44 // so we can't destroy it until it's been used and reset to invalid tid
45 void restore_tid_data(void *ptr
) {
46 thread_local_data_t
*data
= (thread_local_data_t
*)ptr
;
47 if (data
->current_thread_id
!= kInvalidTid
)
48 pthread_setspecific(key
, data
);
51 static void make_tls_key() {
52 CHECK_EQ(pthread_key_create(&key
, restore_tid_data
), 0);
55 static thread_local_data_t
*get_tls_val(bool alloc
) {
56 pthread_once(&key_once
, make_tls_key
);
58 thread_local_data_t
*ptr
= (thread_local_data_t
*)pthread_getspecific(key
);
59 if (ptr
== NULL
&& alloc
) {
60 ptr
= (thread_local_data_t
*)InternalAlloc(sizeof(*ptr
));
61 ptr
->disable_counter
= 0;
62 ptr
->current_thread_id
= kInvalidTid
;
63 ptr
->cache
= AllocatorCache();
64 pthread_setspecific(key
, ptr
);
70 bool DisabledInThisThread() {
71 thread_local_data_t
*data
= get_tls_val(false);
72 return data
? data
->disable_counter
> 0 : false;
75 void DisableInThisThread() { ++get_tls_val(true)->disable_counter
; }
77 void EnableInThisThread() {
78 int *disable_counter
= &get_tls_val(true)->disable_counter
;
79 if (*disable_counter
== 0) {
80 DisableCounterUnderflow();
85 u32
GetCurrentThread() {
86 thread_local_data_t
*data
= get_tls_val(false);
87 return data
? data
->current_thread_id
: kInvalidTid
;
90 void SetCurrentThread(u32 tid
) { get_tls_val(true)->current_thread_id
= tid
; }
92 AllocatorCache
*GetAllocatorCache() { return &get_tls_val(true)->cache
; }
94 LoadedModule
*GetLinker() { return nullptr; }
96 // Required on Linux for initialization of TLS behavior, but should not be
97 // required on Darwin.
98 void InitializePlatformSpecificModules() {}
100 // Sections which can't contain contain global pointers. This list errs on the
101 // side of caution to avoid false positives, at the expense of performance.
103 // Other potentially safe sections include:
104 // __all_image_info, __crash_info, __const, __got, __interpose, __objc_msg_break
106 // Sections which definitely cannot be included here are:
107 // __objc_data, __objc_const, __data, __bss, __common, __thread_data,
108 // __thread_bss, __thread_vars, __objc_opt_rw, __objc_opt_ptrs
109 static const char *kSkippedSecNames
[] = {
110 "__cfstring", "__la_symbol_ptr", "__mod_init_func",
111 "__mod_term_func", "__nl_symbol_ptr", "__objc_classlist",
112 "__objc_classrefs", "__objc_imageinfo", "__objc_nlclslist",
113 "__objc_protolist", "__objc_selrefs", "__objc_superrefs"};
115 // Scans global variables for heap pointers.
116 void ProcessGlobalRegions(Frontier
*frontier
) {
117 for (auto name
: kSkippedSecNames
) CHECK(ARRAY_SIZE(name
) < kMaxSegName
);
119 MemoryMappingLayout
memory_mapping(false);
120 InternalMmapVector
<LoadedModule
> modules(/*initial_capacity*/ 128);
121 memory_mapping
.DumpListOfModules(&modules
);
122 for (uptr i
= 0; i
< modules
.size(); ++i
) {
123 // Even when global scanning is disabled, we still need to scan
124 // system libraries for stashed pointers
125 if (!flags()->use_globals
&& modules
[i
].instrumented()) continue;
127 for (const __sanitizer::LoadedModule::AddressRange
&range
:
128 modules
[i
].ranges()) {
129 // Sections storing global variables are writable and non-executable
130 if (range
.executable
|| !range
.writable
) continue;
132 for (auto name
: kSkippedSecNames
) {
133 if (!internal_strcmp(range
.name
, name
)) continue;
136 ScanGlobalRange(range
.beg
, range
.end
, frontier
);
141 void ProcessPlatformSpecificAllocations(Frontier
*frontier
) {
142 mach_port_name_t port
;
143 if (task_for_pid(mach_task_self(), internal_getpid(), &port
)
150 vm_address_t address
= 0;
151 kern_return_t err
= KERN_SUCCESS
;
152 mach_msg_type_number_t count
= VM_REGION_SUBMAP_INFO_COUNT_64
;
154 InternalMmapVector
<RootRegion
> const *root_regions
= GetRootRegions();
156 while (err
== KERN_SUCCESS
) {
157 struct vm_region_submap_info_64 info
;
158 err
= vm_region_recurse_64(port
, &address
, &size
, &depth
,
159 (vm_region_info_t
)&info
, &count
);
161 uptr end_address
= address
+ size
;
163 // libxpc stashes some pointers in the Kernel Alloc Once page,
164 // make sure not to report those as leaks.
165 if (info
.user_tag
== kSanitizerVmMemoryOsAllocOnce
) {
166 ScanRangeForPointers(address
, end_address
, frontier
, "GLOBAL",
169 // Recursing over the full memory map is very slow, break out
170 // early if we don't need the full iteration.
171 if (!flags()->use_root_regions
|| !root_regions
->size())
175 // This additional root region scan is required on Darwin in order to
176 // detect root regions contained within mmap'd memory regions, because
177 // the Darwin implementation of sanitizer_procmaps traverses images
178 // as loaded by dyld, and not the complete set of all memory regions.
180 // TODO(fjricci) - remove this once sanitizer_procmaps_mac has the same
181 // behavior as sanitizer_procmaps_linux and traverses all memory regions
182 if (flags()->use_root_regions
) {
183 for (uptr i
= 0; i
< root_regions
->size(); i
++) {
184 ScanRootRegion(frontier
, (*root_regions
)[i
], address
, end_address
,
185 info
.protection
& kProtectionRead
);
189 address
= end_address
;
193 // On darwin, we can intercept _exit gracefully, and return a failing exit code
194 // if required at that point. Calling Die() here is undefined behavior and
195 // causes rare race conditions.
196 void HandleLeaks() {}
198 void DoStopTheWorld(StopTheWorldCallback callback
, void *argument
) {
199 StopTheWorld(callback
, argument
);
202 } // namespace __lsan
204 #endif // CAN_SANITIZE_LEAKS && SANITIZER_MAC