libsanitizer/asan/asan_mac.cpp - gcc - Git at Google

 //===-- asan_mac.cpp ------------------------------------------------------===//
 //
 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
 // See https://llvm.org/LICENSE.txt for license information.
 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
 //
 //===----------------------------------------------------------------------===//
 //
 // This file is a part of AddressSanitizer, an address sanity checker.
 //
 // Mac-specific details.
 //===----------------------------------------------------------------------===//

 #include "sanitizer_common/sanitizer_platform.h"
 #if SANITIZER_APPLE

 #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() {
   return MapDynamicShadow(MemToShadowSize(kHighMemEnd), ASAN_SHADOW_SCALE,
                           /*min_shadow_base_alignment*/ 0, kHighMemEnd);
 }

 // 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 FlushUnneededASanShadowMemory(uptr p, uptr size) {
   // Since asan's mapping is compacting, the shadow chunk may be
   // not page-aligned, so we only flush the page-aligned portion.
   ReleaseMemoryPagesToOS(MemToShadow(p), MemToShadow(p + size));
 }

 void ReadContextStack(void *context, uptr *stack, uptr *ssize) {
   UNIMPLEMENTED();
 }

 void ResetContextStack(void *context) { 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(), ThreadType::Worker,
                                      nullptr);
     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;

 // 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_APPLE
	//===-- asan_mac.cpp ------------------------------------------------------===//
	//
	// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
	// See https://llvm.org/LICENSE.txt for license information.
	// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
	//
	//===----------------------------------------------------------------------===//
	//
	// This file is a part of AddressSanitizer, an address sanity checker.
	//
	// Mac-specific details.
	//===----------------------------------------------------------------------===//

	#include "sanitizer_common/sanitizer_platform.h"
	#if SANITIZER_APPLE

	#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() {
	return MapDynamicShadow(MemToShadowSize(kHighMemEnd), ASAN_SHADOW_SCALE,
	/min_shadow_base_alignment/ 0, kHighMemEnd);
	}

	// 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 FlushUnneededASanShadowMemory(uptr p, uptr size) {
	// Since asan's mapping is compacting, the shadow chunk may be
	// not page-aligned, so we only flush the page-aligned portion.
	ReleaseMemoryPagesToOS(MemToShadow(p), MemToShadow(p + size));
	}

	void ReadContextStack(void context, uptr stack, uptr *ssize) {
	UNIMPLEMENTED();
	}

	void ResetContextStack(void *context) { 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(), ThreadType::Worker,
	nullptr);
	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;

	// 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_APPLE