| //===-- asan_mac.cc -------------------------------------------------------===// |
| // |
| // The LLVM Compiler Infrastructure |
| // |
| // This file is distributed under the University of Illinois Open Source |
| // License. See LICENSE.TXT for details. |
| // |
| //===----------------------------------------------------------------------===// |
| // |
| // This file is a part of AddressSanitizer, an address sanity checker. |
| // |
| // Mac-specific details. |
| //===----------------------------------------------------------------------===// |
| |
| #include "sanitizer_common/sanitizer_platform.h" |
| #if SANITIZER_MAC |
| |
| #include "asan_interceptors.h" |
| #include "asan_internal.h" |
| #include "asan_mapping.h" |
| #include "asan_stack.h" |
| #include "asan_thread.h" |
| #include "sanitizer_common/sanitizer_atomic.h" |
| #include "sanitizer_common/sanitizer_libc.h" |
| #include "sanitizer_common/sanitizer_mac.h" |
| |
| #include <dlfcn.h> |
| #include <fcntl.h> |
| #include <libkern/OSAtomic.h> |
| #include <mach-o/dyld.h> |
| #include <mach-o/getsect.h> |
| #include <mach-o/loader.h> |
| #include <pthread.h> |
| #include <stdlib.h> // for free() |
| #include <sys/mman.h> |
| #include <sys/resource.h> |
| #include <sys/sysctl.h> |
| #include <sys/ucontext.h> |
| #include <unistd.h> |
| |
| // from <crt_externs.h>, but we don't have that file on iOS |
| extern "C" { |
| extern char ***_NSGetArgv(void); |
| extern char ***_NSGetEnviron(void); |
| } |
| |
| namespace __asan { |
| |
| void InitializePlatformInterceptors() {} |
| void InitializePlatformExceptionHandlers() {} |
| bool IsSystemHeapAddress (uptr addr) { return false; } |
| |
| // No-op. Mac does not support static linkage anyway. |
| void *AsanDoesNotSupportStaticLinkage() { |
| return 0; |
| } |
| |
| uptr FindDynamicShadowStart() { |
| uptr granularity = GetMmapGranularity(); |
| uptr alignment = 8 * granularity; |
| uptr left_padding = granularity; |
| uptr space_size = kHighShadowEnd + left_padding; |
| |
| uptr largest_gap_found = 0; |
| uptr max_occupied_addr = 0; |
| VReport(2, "FindDynamicShadowStart, space_size = %p\n", space_size); |
| uptr shadow_start = |
| FindAvailableMemoryRange(space_size, alignment, granularity, |
| &largest_gap_found, &max_occupied_addr); |
| // If the shadow doesn't fit, restrict the address space to make it fit. |
| if (shadow_start == 0) { |
| VReport( |
| 2, |
| "Shadow doesn't fit, largest_gap_found = %p, max_occupied_addr = %p\n", |
| largest_gap_found, max_occupied_addr); |
| uptr new_max_vm = RoundDownTo(largest_gap_found << SHADOW_SCALE, alignment); |
| if (new_max_vm < max_occupied_addr) { |
| Report("Unable to find a memory range for dynamic shadow.\n"); |
| Report( |
| "space_size = %p, largest_gap_found = %p, max_occupied_addr = %p, " |
| "new_max_vm = %p\n", |
| space_size, largest_gap_found, max_occupied_addr, new_max_vm); |
| CHECK(0 && "cannot place shadow"); |
| } |
| RestrictMemoryToMaxAddress(new_max_vm); |
| kHighMemEnd = new_max_vm - 1; |
| space_size = kHighShadowEnd + left_padding; |
| VReport(2, "FindDynamicShadowStart, space_size = %p\n", space_size); |
| shadow_start = FindAvailableMemoryRange(space_size, alignment, granularity, |
| nullptr, nullptr); |
| if (shadow_start == 0) { |
| Report("Unable to find a memory range after restricting VM.\n"); |
| CHECK(0 && "cannot place shadow after restricting vm"); |
| } |
| } |
| CHECK_NE((uptr)0, shadow_start); |
| CHECK(IsAligned(shadow_start, alignment)); |
| return shadow_start; |
| } |
| |
| // No-op. Mac does not support static linkage anyway. |
| void AsanCheckDynamicRTPrereqs() {} |
| |
| // No-op. Mac does not support static linkage anyway. |
| void AsanCheckIncompatibleRT() {} |
| |
| void AsanApplyToGlobals(globals_op_fptr op, const void *needle) { |
| // Find the Mach-O header for the image containing the needle |
| Dl_info info; |
| int err = dladdr(needle, &info); |
| if (err == 0) return; |
| |
| #if __LP64__ |
| const struct mach_header_64 *mh = (struct mach_header_64 *)info.dli_fbase; |
| #else |
| const struct mach_header *mh = (struct mach_header *)info.dli_fbase; |
| #endif |
| |
| // Look up the __asan_globals section in that image and register its globals |
| unsigned long size = 0; |
| __asan_global *globals = (__asan_global *)getsectiondata( |
| mh, |
| "__DATA", "__asan_globals", |
| &size); |
| |
| if (!globals) return; |
| if (size % sizeof(__asan_global) != 0) return; |
| op(globals, size / sizeof(__asan_global)); |
| } |
| |
| void ReadContextStack(void *context, uptr *stack, uptr *ssize) { |
| UNIMPLEMENTED(); |
| } |
| |
| // Support for the following functions from libdispatch on Mac OS: |
| // dispatch_async_f() |
| // dispatch_async() |
| // dispatch_sync_f() |
| // dispatch_sync() |
| // dispatch_after_f() |
| // dispatch_after() |
| // dispatch_group_async_f() |
| // dispatch_group_async() |
| // TODO(glider): libdispatch API contains other functions that we don't support |
| // yet. |
| // |
| // dispatch_sync() and dispatch_sync_f() are synchronous, although chances are |
| // they can cause jobs to run on a thread different from the current one. |
| // TODO(glider): if so, we need a test for this (otherwise we should remove |
| // them). |
| // |
| // The following functions use dispatch_barrier_async_f() (which isn't a library |
| // function but is exported) and are thus supported: |
| // dispatch_source_set_cancel_handler_f() |
| // dispatch_source_set_cancel_handler() |
| // dispatch_source_set_event_handler_f() |
| // dispatch_source_set_event_handler() |
| // |
| // The reference manual for Grand Central Dispatch is available at |
| // http://developer.apple.com/library/mac/#documentation/Performance/Reference/GCD_libdispatch_Ref/Reference/reference.html |
| // The implementation details are at |
| // http://libdispatch.macosforge.org/trac/browser/trunk/src/queue.c |
| |
| typedef void* dispatch_group_t; |
| typedef void* dispatch_queue_t; |
| typedef void* dispatch_source_t; |
| typedef u64 dispatch_time_t; |
| typedef void (*dispatch_function_t)(void *block); |
| typedef void* (*worker_t)(void *block); |
| |
| // A wrapper for the ObjC blocks used to support libdispatch. |
| typedef struct { |
| void *block; |
| dispatch_function_t func; |
| u32 parent_tid; |
| } asan_block_context_t; |
| |
| ALWAYS_INLINE |
| void asan_register_worker_thread(int parent_tid, StackTrace *stack) { |
| AsanThread *t = GetCurrentThread(); |
| if (!t) { |
| t = AsanThread::Create(/* start_routine */ nullptr, /* arg */ nullptr, |
| parent_tid, stack, /* detached */ true); |
| t->Init(); |
| asanThreadRegistry().StartThread(t->tid(), GetTid(), |
| /* workerthread */ true, 0); |
| SetCurrentThread(t); |
| } |
| } |
| |
| // For use by only those functions that allocated the context via |
| // alloc_asan_context(). |
| extern "C" |
| void asan_dispatch_call_block_and_release(void *block) { |
| GET_STACK_TRACE_THREAD; |
| asan_block_context_t *context = (asan_block_context_t*)block; |
| VReport(2, |
| "asan_dispatch_call_block_and_release(): " |
| "context: %p, pthread_self: %p\n", |
| block, pthread_self()); |
| asan_register_worker_thread(context->parent_tid, &stack); |
| // Call the original dispatcher for the block. |
| context->func(context->block); |
| asan_free(context, &stack, FROM_MALLOC); |
| } |
| |
| } // namespace __asan |
| |
| using namespace __asan; // NOLINT |
| |
| // Wrap |ctxt| and |func| into an asan_block_context_t. |
| // The caller retains control of the allocated context. |
| extern "C" |
| asan_block_context_t *alloc_asan_context(void *ctxt, dispatch_function_t func, |
| BufferedStackTrace *stack) { |
| asan_block_context_t *asan_ctxt = |
| (asan_block_context_t*) asan_malloc(sizeof(asan_block_context_t), stack); |
| asan_ctxt->block = ctxt; |
| asan_ctxt->func = func; |
| asan_ctxt->parent_tid = GetCurrentTidOrInvalid(); |
| return asan_ctxt; |
| } |
| |
| // Define interceptor for dispatch_*_f function with the three most common |
| // parameters: dispatch_queue_t, context, dispatch_function_t. |
| #define INTERCEPT_DISPATCH_X_F_3(dispatch_x_f) \ |
| INTERCEPTOR(void, dispatch_x_f, dispatch_queue_t dq, void *ctxt, \ |
| dispatch_function_t func) { \ |
| GET_STACK_TRACE_THREAD; \ |
| asan_block_context_t *asan_ctxt = alloc_asan_context(ctxt, func, &stack); \ |
| if (Verbosity() >= 2) { \ |
| Report(#dispatch_x_f "(): context: %p, pthread_self: %p\n", \ |
| asan_ctxt, pthread_self()); \ |
| PRINT_CURRENT_STACK(); \ |
| } \ |
| return REAL(dispatch_x_f)(dq, (void*)asan_ctxt, \ |
| asan_dispatch_call_block_and_release); \ |
| } |
| |
| INTERCEPT_DISPATCH_X_F_3(dispatch_async_f) |
| INTERCEPT_DISPATCH_X_F_3(dispatch_sync_f) |
| INTERCEPT_DISPATCH_X_F_3(dispatch_barrier_async_f) |
| |
| INTERCEPTOR(void, dispatch_after_f, dispatch_time_t when, |
| dispatch_queue_t dq, void *ctxt, |
| dispatch_function_t func) { |
| GET_STACK_TRACE_THREAD; |
| asan_block_context_t *asan_ctxt = alloc_asan_context(ctxt, func, &stack); |
| if (Verbosity() >= 2) { |
| Report("dispatch_after_f: %p\n", asan_ctxt); |
| PRINT_CURRENT_STACK(); |
| } |
| return REAL(dispatch_after_f)(when, dq, (void*)asan_ctxt, |
| asan_dispatch_call_block_and_release); |
| } |
| |
| INTERCEPTOR(void, dispatch_group_async_f, dispatch_group_t group, |
| dispatch_queue_t dq, void *ctxt, |
| dispatch_function_t func) { |
| GET_STACK_TRACE_THREAD; |
| asan_block_context_t *asan_ctxt = alloc_asan_context(ctxt, func, &stack); |
| if (Verbosity() >= 2) { |
| Report("dispatch_group_async_f(): context: %p, pthread_self: %p\n", |
| asan_ctxt, pthread_self()); |
| PRINT_CURRENT_STACK(); |
| } |
| REAL(dispatch_group_async_f)(group, dq, (void*)asan_ctxt, |
| asan_dispatch_call_block_and_release); |
| } |
| |
| #if !defined(MISSING_BLOCKS_SUPPORT) |
| extern "C" { |
| void dispatch_async(dispatch_queue_t dq, void(^work)(void)); |
| void dispatch_group_async(dispatch_group_t dg, dispatch_queue_t dq, |
| void(^work)(void)); |
| void dispatch_after(dispatch_time_t when, dispatch_queue_t queue, |
| void(^work)(void)); |
| void dispatch_source_set_cancel_handler(dispatch_source_t ds, |
| void(^work)(void)); |
| void dispatch_source_set_event_handler(dispatch_source_t ds, void(^work)(void)); |
| } |
| |
| #define GET_ASAN_BLOCK(work) \ |
| void (^asan_block)(void); \ |
| int parent_tid = GetCurrentTidOrInvalid(); \ |
| asan_block = ^(void) { \ |
| GET_STACK_TRACE_THREAD; \ |
| asan_register_worker_thread(parent_tid, &stack); \ |
| work(); \ |
| } |
| |
| INTERCEPTOR(void, dispatch_async, |
| dispatch_queue_t dq, void(^work)(void)) { |
| ENABLE_FRAME_POINTER; |
| GET_ASAN_BLOCK(work); |
| REAL(dispatch_async)(dq, asan_block); |
| } |
| |
| INTERCEPTOR(void, dispatch_group_async, |
| dispatch_group_t dg, dispatch_queue_t dq, void(^work)(void)) { |
| ENABLE_FRAME_POINTER; |
| GET_ASAN_BLOCK(work); |
| REAL(dispatch_group_async)(dg, dq, asan_block); |
| } |
| |
| INTERCEPTOR(void, dispatch_after, |
| dispatch_time_t when, dispatch_queue_t queue, void(^work)(void)) { |
| ENABLE_FRAME_POINTER; |
| GET_ASAN_BLOCK(work); |
| REAL(dispatch_after)(when, queue, asan_block); |
| } |
| |
| INTERCEPTOR(void, dispatch_source_set_cancel_handler, |
| dispatch_source_t ds, void(^work)(void)) { |
| if (!work) { |
| REAL(dispatch_source_set_cancel_handler)(ds, work); |
| return; |
| } |
| ENABLE_FRAME_POINTER; |
| GET_ASAN_BLOCK(work); |
| REAL(dispatch_source_set_cancel_handler)(ds, asan_block); |
| } |
| |
| INTERCEPTOR(void, dispatch_source_set_event_handler, |
| dispatch_source_t ds, void(^work)(void)) { |
| ENABLE_FRAME_POINTER; |
| GET_ASAN_BLOCK(work); |
| REAL(dispatch_source_set_event_handler)(ds, asan_block); |
| } |
| #endif |
| |
| #endif // SANITIZER_MAC |
