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1422 1423 1424 1425 1426 1427 1428 1429 1430 1431 1432 1433 1434 1435 1436 1437 1438 1439 1440 1441 1442 1443 1444 1445 1446 1447 1448 1449 1450 1451 1452 1453 1454 1455 1456 1457 1458 1459 1460 1461 1462 1463 1464 1465 1466 1467 1468 1469 1470 1471 1472 1473 1474 1475 1476 1477 1478 1479 1480 1481 1482 1483 1484 1485 1486 1487 1488 1489 1490 1491 1492 1493 1494 1495 1496 1497 1498 1499 1500 1501 1502 1503 1504 1505 1506 | /* * Copyright (c) 2017 Apple Inc. All rights reserved. * * @APPLE_LICENSE_HEADER_START@ * * This file contains Original Code and/or Modifications of Original Code * as defined in and that are subject to the Apple Public Source License * Version 2.0 (the 'License'). You may not use this file except in * compliance with the License. Please obtain a copy of the License at * http://www.opensource.apple.com/apsl/ and read it before using this * file. * * The Original Code and all software distributed under the License are * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES, * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY, * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT. * Please see the License for the specific language governing rights and * limitations under the License. * * @APPLE_LICENSE_HEADER_END@ */ #include <stdint.h> #include <fcntl.h> #include <sys/types.h> #include <sys/stat.h> #include <sys/sysctl.h> #include <mach/mach_time.h> // mach_absolute_time() #include <libkern/OSAtomic.h> #include <vector> #include <algorithm> #include "AllImages.h" #include "libdyldEntryVector.h" #include "Logging.h" #include "Loading.h" #include "Tracing.h" #include "DyldSharedCache.h" #include "PathOverrides.h" #include "Closure.h" #include "ClosureBuilder.h" #include "ClosureFileSystemPhysical.h" extern const char** appleParams; // should be a header for these struct __cxa_range_t { const void* addr; size_t length; }; extern "C" void __cxa_finalize_ranges(const __cxa_range_t ranges[], unsigned int count); VIS_HIDDEN bool gUseDyld3 = false; namespace dyld3 { ///////////////////// AllImages //////////////////////////// AllImages gAllImages; void AllImages::init(const closure::LaunchClosure* closure, const DyldSharedCache* dyldCacheLoadAddress, const char* dyldCachePath, const Array<LoadedImage>& initialImages) { _mainClosure = closure; _initialImages = &initialImages; _dyldCacheAddress = dyldCacheLoadAddress; _dyldCachePath = dyldCachePath; if ( _dyldCacheAddress ) { const dyld_cache_mapping_info* const fileMappings = (dyld_cache_mapping_info*)((uint64_t)_dyldCacheAddress + _dyldCacheAddress->header.mappingOffset); _dyldCacheSlide = (uint64_t)dyldCacheLoadAddress - fileMappings[0].address; _imagesArrays.push_back(dyldCacheLoadAddress->cachedDylibsImageArray()); if ( auto others = dyldCacheLoadAddress->otherOSImageArray() ) _imagesArrays.push_back(others); } _imagesArrays.push_back(_mainClosure->images()); // record first ImageNum to do use for dlopen() calls _mainClosure->images()->forEachImage(^(const dyld3::closure::Image* image, bool& stop) { closure::ImageNum num = image->imageNum(); if ( num >= _nextImageNum ) _nextImageNum = num+1; }); // Make temporary old image array, so libSystem initializers can be debugged STACK_ALLOC_ARRAY(dyld_image_info, oldDyldInfo, initialImages.count()); for (const LoadedImage& li : initialImages) { oldDyldInfo.push_back({li.loadedAddress(), li.image()->path(), 0}); } _oldAllImageInfos->infoArray = &oldDyldInfo[0]; _oldAllImageInfos->infoArrayCount = (uint32_t)oldDyldInfo.count(); _oldAllImageInfos->notification(dyld_image_adding, _oldAllImageInfos->infoArrayCount, _oldAllImageInfos->infoArray); _oldAllImageInfos->infoArray = nullptr; _oldAllImageInfos->infoArrayCount = 0; _processDOFs = Loader::dtraceUserProbesEnabled(); } void AllImages::setProgramVars(ProgramVars* vars) { _programVars = vars; const dyld3::MachOFile* mf = (dyld3::MachOFile*)_programVars->mh; mf->forEachSupportedPlatform(^(dyld3::Platform platform, uint32_t minOS, uint32_t sdk) { _platform = (dyld_platform_t)platform; //FIXME assert there is only one? }); } void AllImages::setRestrictions(bool allowAtPaths, bool allowEnvPaths) { _allowAtPaths = allowAtPaths; _allowEnvPaths = allowEnvPaths; } void AllImages::applyInitialImages() { addImages(*_initialImages); runImageNotifiers(*_initialImages); _initialImages = nullptr; // this was stack allocated } void AllImages::withReadLock(void (^work)()) const { #ifdef OS_UNFAIR_RECURSIVE_LOCK_INIT os_unfair_recursive_lock_lock(&_loadImagesLock); work(); os_unfair_recursive_lock_unlock(&_loadImagesLock); #else pthread_mutex_lock(&_loadImagesLock); work(); pthread_mutex_unlock(&_loadImagesLock); #endif } void AllImages::withWriteLock(void (^work)()) { #ifdef OS_UNFAIR_RECURSIVE_LOCK_INIT os_unfair_recursive_lock_lock(&_loadImagesLock); work(); os_unfair_recursive_lock_unlock(&_loadImagesLock); #else pthread_mutex_lock(&_loadImagesLock); work(); pthread_mutex_unlock(&_loadImagesLock); #endif } void AllImages::withNotifiersLock(void (^work)()) const { #ifdef OS_UNFAIR_RECURSIVE_LOCK_INIT os_unfair_recursive_lock_lock(&_notifiersLock); work(); os_unfair_recursive_lock_unlock(&_notifiersLock); #else pthread_mutex_lock(&_notifiersLock); work(); pthread_mutex_unlock(&_notifiersLock); #endif } void AllImages::mirrorToOldAllImageInfos() { withReadLock(^(){ // set infoArray to NULL to denote it is in-use _oldAllImageInfos->infoArray = nullptr; // if array not large enough, re-alloc it uint32_t imageCount = (uint32_t)_loadedImages.count(); if ( _oldArrayAllocCount < imageCount ) { uint32_t newAllocCount = imageCount + 16; dyld_image_info* newArray = (dyld_image_info*)::malloc(sizeof(dyld_image_info)*newAllocCount); if ( _oldAllImageArray != nullptr ) { ::memcpy(newArray, _oldAllImageArray, sizeof(dyld_image_info)*_oldAllImageInfos->infoArrayCount); ::free(_oldAllImageArray); } _oldAllImageArray = newArray; _oldArrayAllocCount = newAllocCount; } // fill out array to mirror current image list int index = 0; for (const LoadedImage& li : _loadedImages) { _oldAllImageArray[index].imageLoadAddress = li.loadedAddress(); _oldAllImageArray[index].imageFilePath = imagePath(li.image()); _oldAllImageArray[index].imageFileModDate = 0; ++index; } // set infoArray back to base address of array (so other process can now read) _oldAllImageInfos->infoArrayCount = imageCount; _oldAllImageInfos->infoArrayChangeTimestamp = mach_absolute_time(); _oldAllImageInfos->infoArray = _oldAllImageArray; // <radr://problem/42668846> update UUID array if needed uint32_t nonCachedCount = 1; // always add dyld for (const LoadedImage& li : _loadedImages) { if ( !li.loadedAddress()->inDyldCache() ) ++nonCachedCount; } if ( nonCachedCount != _oldAllImageInfos->uuidArrayCount ) { // set infoArray to NULL to denote it is in-use _oldAllImageInfos->uuidArray = nullptr; // make sure allocation can hold all uuids if ( _oldUUIDAllocCount < nonCachedCount ) { uint32_t newAllocCount = (nonCachedCount + 3) & (-4); // round up to multiple of 4 dyld_uuid_info* newArray = (dyld_uuid_info*)::malloc(sizeof(dyld_uuid_info)*newAllocCount); if ( _oldUUIDArray != nullptr ) ::free(_oldUUIDArray); _oldUUIDArray = newArray; _oldUUIDAllocCount = newAllocCount; } // add dyld then all images not in dyld cache const MachOFile* dyldMF = (MachOFile*)_oldAllImageInfos->dyldImageLoadAddress; _oldUUIDArray[0].imageLoadAddress = dyldMF; dyldMF->getUuid(_oldUUIDArray[0].imageUUID); index = 1; for (const LoadedImage& li : _loadedImages) { if ( !li.loadedAddress()->inDyldCache() ) { _oldUUIDArray[index].imageLoadAddress = li.loadedAddress(); li.loadedAddress()->getUuid(_oldUUIDArray[index].imageUUID); ++index; } } // set uuidArray back to base address of array (so kernel can now read) _oldAllImageInfos->uuidArray = _oldUUIDArray; _oldAllImageInfos->uuidArrayCount = nonCachedCount; } }); } void AllImages::addImages(const Array<LoadedImage>& newImages) { // copy into _loadedImages withWriteLock(^(){ _loadedImages.append(newImages); // if any image not in the shared cache added, recompute bounds for (const LoadedImage& li : newImages) { if ( !((MachOAnalyzer*)li.loadedAddress())->inDyldCache() ) { recomputeBounds(); break; } } }); } void AllImages::runImageNotifiers(const Array<LoadedImage>& newImages) { uint32_t count = (uint32_t)newImages.count(); assert(count != 0); if ( _oldAllImageInfos != nullptr ) { // sync to old all image infos struct mirrorToOldAllImageInfos(); // tell debugger about new images dyld_image_info oldDyldInfo[count]; for (uint32_t i=0; i < count; ++i) { oldDyldInfo[i].imageLoadAddress = newImages[i].loadedAddress(); oldDyldInfo[i].imageFilePath = imagePath(newImages[i].image()); oldDyldInfo[i].imageFileModDate = 0; } _oldAllImageInfos->notification(dyld_image_adding, count, oldDyldInfo); } // log loads for (const LoadedImage& li : newImages) { log_loads("dyld: %s\n", imagePath(li.image())); } #if !TARGET_IPHONE_SIMULATOR // call kdebug trace for each image if (kdebug_is_enabled(KDBG_CODE(DBG_DYLD, DBG_DYLD_UUID, DBG_DYLD_UUID_MAP_A))) { for (const LoadedImage& li : newImages) { const closure::Image* image = li.image(); struct stat stat_buf; fsid_t fsid = {{ 0, 0 }}; fsobj_id_t fsobjid = { 0, 0 }; if ( !image->inDyldCache() && (stat(imagePath(image), &stat_buf) == 0) ) { fsobjid = *(fsobj_id_t*)&stat_buf.st_ino; fsid = {{ stat_buf.st_dev, 0 }}; } uuid_t uuid; image->getUuid(uuid); kdebug_trace_dyld_image(DBG_DYLD_UUID_MAP_A, &uuid, fsobjid, fsid, li.loadedAddress()); } } #endif // call each _dyld_register_func_for_add_image function with each image withNotifiersLock(^{ for (NotifyFunc func : _loadNotifiers) { for (const LoadedImage& li : newImages) { dyld3::ScopedTimer timer(DBG_DYLD_TIMING_FUNC_FOR_ADD_IMAGE, (uint64_t)li.loadedAddress(), (uint64_t)func, 0); log_notifications("dyld: add notifier %p called with mh=%p\n", func, li.loadedAddress()); if ( li.image()->inDyldCache() ) func(li.loadedAddress(), (uintptr_t)_dyldCacheSlide); else func(li.loadedAddress(), li.loadedAddress()->getSlide()); } } for (LoadNotifyFunc func : _loadNotifiers2) { for (const LoadedImage& li : newImages) { dyld3::ScopedTimer timer(DBG_DYLD_TIMING_FUNC_FOR_ADD_IMAGE, (uint64_t)li.loadedAddress(), (uint64_t)func, 0); log_notifications("dyld: add notifier %p called with mh=%p\n", func, li.loadedAddress()); if ( li.image()->inDyldCache() ) func(li.loadedAddress(), li.image()->path(), false); else func(li.loadedAddress(), li.image()->path(), !li.image()->neverUnload()); } } }); // call objc about images that use objc if ( _objcNotifyMapped != nullptr ) { const char* pathsBuffer[count]; const mach_header* mhBuffer[count]; uint32_t imagesWithObjC = 0; for (const LoadedImage& li : newImages) { const closure::Image* image = li.image(); if ( image->hasObjC() ) { pathsBuffer[imagesWithObjC] = imagePath(image); mhBuffer[imagesWithObjC] = li.loadedAddress(); ++imagesWithObjC; } } if ( imagesWithObjC != 0 ) { dyld3::ScopedTimer timer(DBG_DYLD_TIMING_OBJC_MAP, 0, 0, 0); (*_objcNotifyMapped)(imagesWithObjC, pathsBuffer, mhBuffer); if ( log_notifications("dyld: objc-mapped-notifier called with %d images:\n", imagesWithObjC) ) { for (uint32_t i=0; i < imagesWithObjC; ++i) { log_notifications("dyld: objc-mapped: %p %s\n", mhBuffer[i], pathsBuffer[i]); } } } } // notify any processes tracking loads in this process notifyMonitorLoads(newImages); } void AllImages::removeImages(const Array<LoadedImage>& unloadImages) { // call each _dyld_register_func_for_remove_image function with each image withNotifiersLock(^{ for (NotifyFunc func : _unloadNotifiers) { for (const LoadedImage& li : unloadImages) { dyld3::ScopedTimer timer(DBG_DYLD_TIMING_FUNC_FOR_REMOVE_IMAGE, (uint64_t)li.loadedAddress(), (uint64_t)func, 0); log_notifications("dyld: remove notifier %p called with mh=%p\n", func, li.loadedAddress()); if ( li.image()->inDyldCache() ) func(li.loadedAddress(), (uintptr_t)_dyldCacheSlide); else func(li.loadedAddress(), li.loadedAddress()->getSlide()); } } }); // call objc about images going away if ( _objcNotifyUnmapped != nullptr ) { for (const LoadedImage& li : unloadImages) { if ( li.image()->hasObjC() ) { (*_objcNotifyUnmapped)(imagePath(li.image()), li.loadedAddress()); log_notifications("dyld: objc-unmapped-notifier called with image %p %s\n", li.loadedAddress(), imagePath(li.image())); } } } #if !TARGET_IPHONE_SIMULATOR // call kdebug trace for each image if (kdebug_is_enabled(KDBG_CODE(DBG_DYLD, DBG_DYLD_UUID, DBG_DYLD_UUID_MAP_A))) { for (const LoadedImage& li : unloadImages) { const closure::Image* image = li.image(); struct stat stat_buf; fsid_t fsid = {{ 0, 0 }}; fsobj_id_t fsobjid = { 0, 0 }; if ( stat(imagePath(image), &stat_buf) == 0 ) { fsobjid = *(fsobj_id_t*)&stat_buf.st_ino; fsid = {{ stat_buf.st_dev, 0 }}; } uuid_t uuid; image->getUuid(uuid); kdebug_trace_dyld_image(DBG_DYLD_UUID_UNMAP_A, &uuid, fsobjid, fsid, li.loadedAddress()); } } #endif // remove each from _loadedImages withWriteLock(^(){ for (const LoadedImage& uli : unloadImages) { for (LoadedImage& li : _loadedImages) { if ( uli.loadedAddress() == li.loadedAddress() ) { _loadedImages.erase(li); break; } } } recomputeBounds(); }); // sync to old all image infos struct mirrorToOldAllImageInfos(); // tell debugger about removed images STACK_ALLOC_ARRAY(dyld_image_info, oldDyldInfo, unloadImages.count()); for (const LoadedImage& li : unloadImages) { oldDyldInfo.push_back({li.loadedAddress(), li.image()->path(), 0}); } _oldAllImageInfos->notification(dyld_image_removing, (uint32_t)oldDyldInfo.count(), &oldDyldInfo[0]); // notify any processes tracking loads in this process notifyMonitorUnloads(unloadImages); // finally, unmap images for (const LoadedImage& li : unloadImages) { if ( li.leaveMapped() ) { log_loads("dyld: unloaded but left mmapped %s\n", imagePath(li.image())); } else { // unmapImage() modifies parameter, so use copy LoadedImage copy = li; Loader::unmapImage(copy); log_loads("dyld: unloaded %s\n", imagePath(li.image())); } } } // must be called with writeLock held void AllImages::recomputeBounds() { _lowestNonCached = UINTPTR_MAX; _highestNonCached = 0; for (const LoadedImage& li : _loadedImages) { const MachOLoaded* ml = li.loadedAddress(); uintptr_t start = (uintptr_t)ml; if ( !((MachOAnalyzer*)ml)->inDyldCache() ) { if ( start < _lowestNonCached ) _lowestNonCached = start; uintptr_t end = start + (uintptr_t)(li.image()->vmSizeToMap()); if ( end > _highestNonCached ) _highestNonCached = end; } } } uint32_t AllImages::count() const { return (uint32_t)_loadedImages.count(); } bool AllImages::dyldCacheHasPath(const char* path) const { uint32_t dyldCacheImageIndex; if ( _dyldCacheAddress != nullptr ) return _dyldCacheAddress->hasImagePath(path, dyldCacheImageIndex); return false; } const char* AllImages::imagePathByIndex(uint32_t index) const { if ( index < _loadedImages.count() ) return imagePath(_loadedImages[index].image()); return nullptr; } const mach_header* AllImages::imageLoadAddressByIndex(uint32_t index) const { if ( index < _loadedImages.count() ) return _loadedImages[index].loadedAddress(); return nullptr; } bool AllImages::findImage(const mach_header* loadAddress, LoadedImage& foundImage) const { __block bool result = false; withReadLock(^(){ for (const LoadedImage& li : _loadedImages) { if ( li.loadedAddress() == loadAddress ) { foundImage = li; result = true; break; } } }); return result; } void AllImages::forEachImage(void (^handler)(const LoadedImage& loadedImage, bool& stop)) const { withReadLock(^{ bool stop = false; for (const LoadedImage& li : _loadedImages) { handler(li, stop); if ( stop ) break; } }); } const char* AllImages::pathForImageMappedAt(const void* addr) const { if ( _initialImages != nullptr ) { // being called during libSystem initialization, so _loadedImages not allocated yet for (const LoadedImage& li : *_initialImages) { uint8_t permissions; if ( li.image()->containsAddress(addr, li.loadedAddress(), &permissions) ) { return li.image()->path(); } } return nullptr; } // if address is in cache, do fast search of TEXT segments in cache __block const char* result = nullptr; if ( (_dyldCacheAddress != nullptr) && (addr > _dyldCacheAddress) ) { if ( addr < (void*)((uint8_t*)_dyldCacheAddress+_dyldCacheAddress->mappedSize()) ) { uint64_t cacheSlide = (uint64_t)_dyldCacheAddress - _dyldCacheAddress->unslidLoadAddress(); uint64_t unslidTargetAddr = (uint64_t)addr - cacheSlide; _dyldCacheAddress->forEachImageTextSegment(^(uint64_t loadAddressUnslid, uint64_t textSegmentSize, const unsigned char* dylibUUID, const char* installName, bool& stop) { if ( (loadAddressUnslid <= unslidTargetAddr) && (unslidTargetAddr < loadAddressUnslid+textSegmentSize) ) { result = installName; stop = true; } }); if ( result != nullptr ) return result; } } // slow path - search image list infoForImageMappedAt(addr, ^(const LoadedImage& foundImage, uint8_t permissions) { result = foundImage.image()->path(); }); return result; } void AllImages::infoForImageMappedAt(const void* addr, void (^handler)(const LoadedImage& foundImage, uint8_t permissions)) const { __block uint8_t permissions; if ( _initialImages != nullptr ) { // being called during libSystem initialization, so _loadedImages not allocated yet for (const LoadedImage& li : *_initialImages) { if ( li.image()->containsAddress(addr, li.loadedAddress(), &permissions) ) { handler(li, permissions); break; } } return; } withReadLock(^{ for (const LoadedImage& li : _loadedImages) { if ( li.image()->containsAddress(addr, li.loadedAddress(), &permissions) ) { handler(li, permissions); break; } } }); } bool AllImages::infoForImageMappedAt(const void* addr, const MachOLoaded** ml, uint64_t* textSize, const char** path) const { if ( _initialImages != nullptr ) { // being called during libSystem initialization, so _loadedImages not allocated yet for (const LoadedImage& li : *_initialImages) { uint8_t permissions; if ( li.image()->containsAddress(addr, li.loadedAddress(), &permissions) ) { if ( ml != nullptr ) *ml = li.loadedAddress(); if ( path != nullptr ) *path = li.image()->path(); if ( textSize != nullptr ) { *textSize = li.image()->textSize(); } return true; } } return false; } // if address is in cache, do fast search of TEXT segments in cache __block bool result = false; if ( (_dyldCacheAddress != nullptr) && (addr > _dyldCacheAddress) ) { if ( addr < (void*)((uint8_t*)_dyldCacheAddress+_dyldCacheAddress->mappedSize()) ) { uint64_t cacheSlide = (uint64_t)_dyldCacheAddress - _dyldCacheAddress->unslidLoadAddress(); uint64_t unslidTargetAddr = (uint64_t)addr - cacheSlide; _dyldCacheAddress->forEachImageTextSegment(^(uint64_t loadAddressUnslid, uint64_t textSegmentSize, const unsigned char* dylibUUID, const char* installName, bool& stop) { if ( (loadAddressUnslid <= unslidTargetAddr) && (unslidTargetAddr < loadAddressUnslid+textSegmentSize) ) { if ( ml != nullptr ) *ml = (MachOLoaded*)(loadAddressUnslid + cacheSlide); if ( path != nullptr ) *path = installName; if ( textSize != nullptr ) *textSize = textSegmentSize; stop = true; result = true; } }); if ( result ) return result; } } // slow path - search image list infoForImageMappedAt(addr, ^(const LoadedImage& foundImage, uint8_t permissions) { if ( ml != nullptr ) *ml = foundImage.loadedAddress(); if ( path != nullptr ) *path = foundImage.image()->path(); if ( textSize != nullptr ) *textSize = foundImage.image()->textSize(); result = true; }); return result; } // same as infoForImageMappedAt(), but only look at images not in the dyld cache void AllImages::infoForNonCachedImageMappedAt(const void* addr, void (^handler)(const LoadedImage& foundImage, uint8_t permissions)) const { __block uint8_t permissions; if ( _initialImages != nullptr ) { // being called during libSystem initialization, so _loadedImages not allocated yet for (const LoadedImage& li : *_initialImages) { if ( !((MachOAnalyzer*)li.loadedAddress())->inDyldCache() ) { if ( li.image()->containsAddress(addr, li.loadedAddress(), &permissions) ) { handler(li, permissions); break; } } } return; } withReadLock(^{ for (const LoadedImage& li : _loadedImages) { if ( !((MachOAnalyzer*)li.loadedAddress())->inDyldCache() ) { if ( li.image()->containsAddress(addr, li.loadedAddress(), &permissions) ) { handler(li, permissions); break; } } } }); } bool AllImages::immutableMemory(const void* addr, size_t length) const { // quick check to see if in shared cache if ( _dyldCacheAddress != nullptr ) { bool readOnly; if ( _dyldCacheAddress->inCache(addr, length, readOnly) ) { return readOnly; } } __block bool result = false; withReadLock(^() { // quick check to see if it is not any non-cached image loaded if ( ((uintptr_t)addr < _lowestNonCached) || ((uintptr_t)addr+length > _highestNonCached) ) { result = false; return; } // slow walk through all images, only look at images not in dyld cache for (const LoadedImage& li : _loadedImages) { if ( !((MachOAnalyzer*)li.loadedAddress())->inDyldCache() ) { uint8_t permissions; if ( li.image()->containsAddress(addr, li.loadedAddress(), &permissions) ) { result = ((permissions & VM_PROT_WRITE) == 0) && li.image()->neverUnload(); break; } } } }); return result; } void AllImages::infoForImageWithLoadAddress(const MachOLoaded* mh, void (^handler)(const LoadedImage& foundImage)) const { withReadLock(^{ for (const LoadedImage& li : _loadedImages) { if ( li.loadedAddress() == mh ) { handler(li); break; } } }); } bool AllImages::findImageNum(closure::ImageNum imageNum, LoadedImage& foundImage) const { if ( _initialImages != nullptr ) { // being called during libSystem initialization, so _loadedImages not allocated yet for (const LoadedImage& li : *_initialImages) { if ( li.image()->representsImageNum(imageNum) ) { foundImage = li; return true; } } return false; } bool result = false; for (const LoadedImage& li : _loadedImages) { if ( li.image()->representsImageNum(imageNum) ) { foundImage = li; result = true; break; } } return result; } const MachOLoaded* AllImages::findDependent(const MachOLoaded* mh, uint32_t depIndex) { __block const MachOLoaded* result = nullptr; withReadLock(^{ for (const LoadedImage& li : _loadedImages) { if ( li.loadedAddress() == mh ) { closure::ImageNum depImageNum = li.image()->dependentImageNum(depIndex); LoadedImage depLi; if ( findImageNum(depImageNum, depLi) ) result = depLi.loadedAddress(); break; } } }); return result; } void AllImages::breadthFirstRecurseDependents(Array<closure::ImageNum>& visited, const LoadedImage& nodeLi, bool& stopped, void (^handler)(const LoadedImage& aLoadedImage, bool& stop)) const { // call handler on all direct dependents (unless already visited) STACK_ALLOC_ARRAY(LoadedImage, dependentsToRecurse, 256); nodeLi.image()->forEachDependentImage(^(uint32_t depIndex, closure::Image::LinkKind kind, closure::ImageNum depImageNum, bool& depStop) { if ( kind == closure::Image::LinkKind::upward ) return; if ( visited.contains(depImageNum) ) return; LoadedImage depLi; if ( !findImageNum(depImageNum, depLi) ) return; handler(depLi, depStop); visited.push_back(depImageNum); if ( depStop ) { stopped = true; return; } dependentsToRecurse.push_back(depLi); }); if ( stopped ) return; // recurse on all dependents just visited for (LoadedImage& depLi : dependentsToRecurse) { breadthFirstRecurseDependents(visited, depLi, stopped, handler); } } void AllImages::visitDependentsTopDown(const LoadedImage& start, void (^handler)(const LoadedImage& aLoadedImage, bool& stop)) const { withReadLock(^{ STACK_ALLOC_ARRAY(closure::ImageNum, visited, count()); bool stop = false; handler(start, stop); if ( stop ) return; visited.push_back(start.image()->imageNum()); breadthFirstRecurseDependents(visited, start, stop, handler); }); } const MachOLoaded* AllImages::mainExecutable() const { assert(_programVars != nullptr); return (const MachOLoaded*)_programVars->mh; } const closure::Image* AllImages::mainExecutableImage() const { assert(_mainClosure != nullptr); return _mainClosure->images()->imageForNum(_mainClosure->topImage()); } void AllImages::setMainPath(const char* path ) { _mainExeOverridePath = path; } const char* AllImages::imagePath(const closure::Image* image) const { #if __IPHONE_OS_VERSION_MIN_REQUIRED // on iOS and watchOS, apps may be moved on device after closure built if ( _mainExeOverridePath != nullptr ) { if ( image == mainExecutableImage() ) return _mainExeOverridePath; } #endif return image->path(); } dyld_platform_t AllImages::platform() const { return _platform; } void AllImages::incRefCount(const mach_header* loadAddress) { for (DlopenCount& entry : _dlopenRefCounts) { if ( entry.loadAddress == loadAddress ) { // found existing DlopenCount entry, bump counter entry.refCount += 1; return; } } // no existing DlopenCount, add new one _dlopenRefCounts.push_back({ loadAddress, 1 }); } void AllImages::decRefCount(const mach_header* loadAddress) { bool doCollect = false; for (DlopenCount& entry : _dlopenRefCounts) { if ( entry.loadAddress == loadAddress ) { // found existing DlopenCount entry, bump counter entry.refCount -= 1; if ( entry.refCount == 0 ) { _dlopenRefCounts.erase(entry); doCollect = true; break; } return; } } if ( doCollect ) garbageCollectImages(); } #if __MAC_OS_X_VERSION_MIN_REQUIRED NSObjectFileImage AllImages::addNSObjectFileImage(const OFIInfo& image) { __block uint64_t imageNum = 0; withWriteLock(^{ imageNum = ++_nextObjectFileImageNum; _objectFileImages.push_back(image); _objectFileImages.back().imageNum = imageNum; }); return (NSObjectFileImage)imageNum; } bool AllImages::forNSObjectFileImage(NSObjectFileImage imageHandle, void (^handler)(OFIInfo& image)) { uint64_t imageNum = (uint64_t)imageHandle; bool __block foundImage = false; withReadLock(^{ for (OFIInfo& ofi : _objectFileImages) { if ( ofi.imageNum == imageNum ) { handler(ofi); foundImage = true; return; } } }); return foundImage; } void AllImages::removeNSObjectFileImage(NSObjectFileImage imageHandle) { uint64_t imageNum = (uint64_t)imageHandle; withWriteLock(^{ for (OFIInfo& ofi : _objectFileImages) { if ( ofi.imageNum == imageNum ) { _objectFileImages.erase(ofi); return; } } }); } #endif class VIS_HIDDEN Reaper { public: struct ImageAndUse { const LoadedImage* li; bool inUse; }; Reaper(Array<ImageAndUse>& unloadables, AllImages*); void garbageCollect(); void finalizeDeadImages(); private: void markDirectlyDlopenedImagesAsUsed(); void markDependentOfInUseImages(); void markDependentsOf(const LoadedImage*); uint32_t inUseCount(); void dump(const char* msg); Array<ImageAndUse>& _unloadables; AllImages* _allImages; uint32_t _deadCount; }; Reaper::Reaper(Array<ImageAndUse>& unloadables, AllImages* all) : _unloadables(unloadables), _allImages(all), _deadCount(0) { } void Reaper::markDirectlyDlopenedImagesAsUsed() { for (AllImages::DlopenCount& entry : _allImages->_dlopenRefCounts) { if ( entry.refCount != 0 ) { for (ImageAndUse& iu : _unloadables) { if ( iu.li->loadedAddress() == entry.loadAddress ) { iu.inUse = true; break; } } } } } uint32_t Reaper::inUseCount() { uint32_t count = 0; for (ImageAndUse& iu : _unloadables) { if ( iu.inUse ) ++count; } return count; } void Reaper::markDependentsOf(const LoadedImage* li) { li->image()->forEachDependentImage(^(uint32_t depIndex, closure::Image::LinkKind kind, closure::ImageNum depImageNum, bool& stop) { for (ImageAndUse& iu : _unloadables) { if ( !iu.inUse && iu.li->image()->representsImageNum(depImageNum) ) { iu.inUse = true; break; } } }); } void Reaper::markDependentOfInUseImages() { for (ImageAndUse& iu : _unloadables) { if ( iu.inUse ) markDependentsOf(iu.li); } } void Reaper::dump(const char* msg) { //log("%s:\n", msg); //for (ImageAndUse& iu : _unloadables) { // log(" in-used=%d %s\n", iu.inUse, iu.li->image()->path()); //} } void Reaper::garbageCollect() { //dump("all unloadable images"); // mark all dylibs directly dlopen'ed as in use markDirectlyDlopenedImagesAsUsed(); //dump("directly dlopen()'ed marked"); // iteratively mark dependents of in-use dylibs as in-use until in-use count stops changing uint32_t lastCount = inUseCount(); bool countChanged = false; do { markDependentOfInUseImages(); //dump("dependents marked"); uint32_t newCount = inUseCount(); countChanged = (newCount != lastCount); lastCount = newCount; } while (countChanged); _deadCount = (uint32_t)_unloadables.count() - inUseCount(); } void Reaper::finalizeDeadImages() { if ( _deadCount == 0 ) return; __cxa_range_t ranges[_deadCount]; __cxa_range_t* rangesArray = ranges; __block unsigned int rangesCount = 0; for (ImageAndUse& iu : _unloadables) { if ( iu.inUse ) continue; iu.li->image()->forEachDiskSegment(^(uint32_t segIndex, uint32_t fileOffset, uint32_t fileSize, int64_t vmOffset, uint64_t vmSize, uint8_t permissions, bool &stop) { if ( permissions & VM_PROT_EXECUTE ) { rangesArray[rangesCount].addr = (char*)(iu.li->loadedAddress()) + vmOffset; rangesArray[rangesCount].length = (size_t)vmSize; ++rangesCount; } }); } __cxa_finalize_ranges(ranges, rangesCount); } // This function is called at the end of dlclose() when the reference count goes to zero. // The dylib being unloaded may have brought in other dependent dylibs when it was loaded. // Those dependent dylibs need to be unloaded, but only if they are not referenced by // something else. We use a standard mark and sweep garbage collection. // // The tricky part is that when a dylib is unloaded it may have a termination function that // can run and itself call dlclose() on yet another dylib. The problem is that this // sort of gabage collection is not re-entrant. Instead a terminator's call to dlclose() // which calls garbageCollectImages() will just set a flag to re-do the garbage collection // when the current pass is done. // // Also note that this is done within the _loadedImages writer lock, so any dlopen/dlclose // on other threads are blocked while this garbage collections runs // void AllImages::garbageCollectImages() { // if some other thread is currently GC'ing images, let other thread do the work int32_t newCount = OSAtomicIncrement32(&_gcCount); if ( newCount != 1 ) return; do { STACK_ALLOC_ARRAY(Reaper::ImageAndUse, unloadables, _loadedImages.count()); withReadLock(^{ for (const LoadedImage& li : _loadedImages) { if ( !li.image()->neverUnload() /*&& !li.neverUnload()*/ ) { unloadables.push_back({&li, false}); //fprintf(stderr, "unloadable[%lu] %p %s\n", unloadables.count(), li.loadedAddress(), li.image()->path()); } } }); // make reaper object to do garbage collection and notifications Reaper reaper(unloadables, this); reaper.garbageCollect(); // FIXME: we should sort dead images so higher level ones are terminated first // call cxa_finalize_ranges of dead images reaper.finalizeDeadImages(); // FIXME: call static terminators of dead images // FIXME: DOF unregister //fprintf(stderr, "_loadedImages before GC removals:\n"); //for (const LoadedImage& li : _loadedImages) { // fprintf(stderr, " loadAddr=%p, path=%s\n", li.loadedAddress(), li.image()->path()); //} // make copy of LoadedImages we want to remove // because unloadables[] points into LoadedImage we are shrinking STACK_ALLOC_ARRAY(LoadedImage, unloadImages, _loadedImages.count()); for (const Reaper::ImageAndUse& iu : unloadables) { if ( !iu.inUse ) unloadImages.push_back(*iu.li); } // remove entries from _loadedImages if ( !unloadImages.empty() ) { removeImages(unloadImages); //fprintf(stderr, "_loadedImages after GC removals:\n"); //for (const LoadedImage& li : _loadedImages) { // fprintf(stderr, " loadAddr=%p, path=%s\n", li.loadedAddress(), li.image()->path()); //} } // if some other thread called GC during our work, redo GC on its behalf newCount = OSAtomicDecrement32(&_gcCount); } while (newCount > 0); } void AllImages::addLoadNotifier(NotifyFunc func) { // callback about already loaded images withReadLock(^{ for (const LoadedImage& li : _loadedImages) { dyld3::ScopedTimer timer(DBG_DYLD_TIMING_FUNC_FOR_ADD_IMAGE, (uint64_t)li.loadedAddress(), (uint64_t)func, 0); log_notifications("dyld: add notifier %p called with mh=%p\n", func, li.loadedAddress()); if ( li.image()->inDyldCache() ) func(li.loadedAddress(), (uintptr_t)_dyldCacheSlide); else func(li.loadedAddress(), li.loadedAddress()->getSlide()); } }); // add to list of functions to call about future loads withNotifiersLock(^{ _loadNotifiers.push_back(func); }); } void AllImages::addUnloadNotifier(NotifyFunc func) { // add to list of functions to call about future unloads withNotifiersLock(^{ _unloadNotifiers.push_back(func); }); } void AllImages::addLoadNotifier(LoadNotifyFunc func) { // callback about already loaded images withReadLock(^{ for (const LoadedImage& li : _loadedImages) { dyld3::ScopedTimer timer(DBG_DYLD_TIMING_FUNC_FOR_ADD_IMAGE, (uint64_t)li.loadedAddress(), (uint64_t)func, 0); log_notifications("dyld: add notifier %p called with mh=%p\n", func, li.loadedAddress()); func(li.loadedAddress(), li.image()->path(), !li.image()->neverUnload()); } }); // add to list of functions to call about future loads withNotifiersLock(^{ _loadNotifiers2.push_back(func); }); } void AllImages::setObjCNotifiers(_dyld_objc_notify_mapped map, _dyld_objc_notify_init init, _dyld_objc_notify_unmapped unmap) { _objcNotifyMapped = map; _objcNotifyInit = init; _objcNotifyUnmapped = unmap; // callback about already loaded images uint32_t maxCount = count(); STACK_ALLOC_ARRAY(const mach_header*, mhs, maxCount); STACK_ALLOC_ARRAY(const char*, paths, maxCount); // don't need _mutex here because this is called when process is still single threaded for (const LoadedImage& li : _loadedImages) { if ( li.image()->hasObjC() ) { paths.push_back(imagePath(li.image())); mhs.push_back(li.loadedAddress()); } } if ( !mhs.empty() ) { (*map)((uint32_t)mhs.count(), &paths[0], &mhs[0]); if ( log_notifications("dyld: objc-mapped-notifier called with %ld images:\n", mhs.count()) ) { for (uintptr_t i=0; i < mhs.count(); ++i) { log_notifications("dyld: objc-mapped: %p %s\n", mhs[i], paths[i]); } } } } void AllImages::applyInterposingToDyldCache(const closure::Closure* closure) { dyld3::ScopedTimer timer(DBG_DYLD_TIMING_APPLY_INTERPOSING, 0, 0, 0); const uintptr_t cacheStart = (uintptr_t)_dyldCacheAddress; __block closure::ImageNum lastCachedDylibImageNum = 0; __block const closure::Image* lastCachedDylibImage = nullptr; __block bool suspendedAccounting = false; closure->forEachPatchEntry(^(const closure::Closure::PatchEntry& entry) { if ( entry.overriddenDylibInCache != lastCachedDylibImageNum ) { lastCachedDylibImage = closure::ImageArray::findImage(imagesArrays(), entry.overriddenDylibInCache); assert(lastCachedDylibImage != nullptr); lastCachedDylibImageNum = entry.overriddenDylibInCache; } if ( !suspendedAccounting ) { Loader::vmAccountingSetSuspended(true, log_fixups); suspendedAccounting = true; } uintptr_t newValue = 0; LoadedImage foundImage; switch ( entry.replacement.image.kind ) { case closure::Image::ResolvedSymbolTarget::kindImage: assert(findImageNum(entry.replacement.image.imageNum, foundImage)); newValue = (uintptr_t)(foundImage.loadedAddress()) + (uintptr_t)entry.replacement.image.offset; break; case closure::Image::ResolvedSymbolTarget::kindSharedCache: newValue = (uintptr_t)_dyldCacheAddress + (uintptr_t)entry.replacement.sharedCache.offset; break; case closure::Image::ResolvedSymbolTarget::kindAbsolute: // this means the symbol was missing in the cache override dylib, so set any uses to NULL newValue = (uintptr_t)entry.replacement.absolute.value; break; default: assert(0 && "bad replacement kind"); } lastCachedDylibImage->forEachPatchableUseOfExport(entry.exportCacheOffset, ^(closure::Image::PatchableExport::PatchLocation patchLocation) { uintptr_t* loc = (uintptr_t*)(cacheStart+patchLocation.cacheOffset); #if __has_feature(ptrauth_calls) if ( patchLocation.authenticated ) { MachOLoaded::ChainedFixupPointerOnDisk fixupInfo; fixupInfo.authRebase.auth = true; fixupInfo.authRebase.addrDiv = patchLocation.usesAddressDiversity; fixupInfo.authRebase.diversity = patchLocation.discriminator; fixupInfo.authRebase.key = patchLocation.key; *loc = fixupInfo.signPointer(loc, newValue + patchLocation.getAddend()); log_fixups("dyld: cache fixup: *%p = %p (JOP: diversity 0x%04X, addr-div=%d, key=%s)\n", loc, (void*)*loc, patchLocation.discriminator, patchLocation.usesAddressDiversity, patchLocation.keyName()); return; } #endif log_fixups("dyld: cache fixup: *%p = 0x%0lX (dyld cache patch)\n", loc, newValue + (uintptr_t)patchLocation.getAddend()); *loc = newValue + (uintptr_t)patchLocation.getAddend(); }); }); if ( suspendedAccounting ) Loader::vmAccountingSetSuspended(false, log_fixups); } void AllImages::runStartupInitialzers() { __block bool mainExecutableInitializerNeedsToRun = true; __block uint32_t imageIndex = 0; while ( mainExecutableInitializerNeedsToRun ) { __block const closure::Image* image = nullptr; withReadLock(^{ image = _loadedImages[imageIndex].image(); if ( _loadedImages[imageIndex].loadedAddress()->isMainExecutable() ) mainExecutableInitializerNeedsToRun = false; }); runInitialzersBottomUp(image); ++imageIndex; } } // Find image in _loadedImages which has ImageNum == num. // Try indexHint first, if hint is wrong, updated it, so next use is faster. LoadedImage AllImages::findImageNum(closure::ImageNum num, uint32_t& indexHint) { __block LoadedImage copy; withReadLock(^{ if ( (indexHint >= _loadedImages.count()) || !_loadedImages[indexHint].image()->representsImageNum(num) ) { indexHint = 0; for (indexHint=0; indexHint < _loadedImages.count(); ++indexHint) { if ( _loadedImages[indexHint].image()->representsImageNum(num) ) break; } assert(indexHint < _loadedImages.count()); } copy = _loadedImages[indexHint]; }); return copy; } // Change the state of the LoadedImage in _loadedImages which has ImageNum == num. // Only change state if current state is expectedCurrentState (atomic swap). bool AllImages::swapImageState(closure::ImageNum num, uint32_t& indexHint, LoadedImage::State expectedCurrentState, LoadedImage::State newState) { __block bool result = false; withWriteLock(^{ if ( (indexHint >= _loadedImages.count()) || !_loadedImages[indexHint].image()->representsImageNum(num) ) { indexHint = 0; for (indexHint=0; indexHint < _loadedImages.count(); ++indexHint) { if ( _loadedImages[indexHint].image()->representsImageNum(num) ) break; } assert(indexHint < _loadedImages.count()); } if ( _loadedImages[indexHint].state() == expectedCurrentState ) { _loadedImages[indexHint].setState(newState); result = true; } }); return result; } // dyld3 pre-builds the order initializers need to be run (bottom up) in a list in the closure. // This method uses that list to run all initializers. // Because an initializer may call dlopen() and/or create threads, the _loadedImages array // may move under us. So, never keep a pointer into it. Always reference images by ImageNum // and use hint to make that faster in the case where the _loadedImages does not move. void AllImages::runInitialzersBottomUp(const closure::Image* topImage) { // walk closure specified initializer list, already ordered bottom up topImage->forEachImageToInitBefore(^(closure::ImageNum imageToInit, bool& stop) { // get copy of LoadedImage about imageToInit, but don't keep reference into _loadedImages, because it may move if initialzers call dlopen() uint32_t indexHint = 0; LoadedImage loadedImageCopy = findImageNum(imageToInit, indexHint); // skip if the image is already inited, or in process of being inited (dependency cycle) if ( (loadedImageCopy.state() == LoadedImage::State::fixedUp) && swapImageState(imageToInit, indexHint, LoadedImage::State::fixedUp, LoadedImage::State::beingInited) ) { // tell objc to run any +load methods in image if ( (_objcNotifyInit != nullptr) && loadedImageCopy.image()->mayHavePlusLoads() ) { dyld3::ScopedTimer timer(DBG_DYLD_TIMING_OBJC_INIT, (uint64_t)loadedImageCopy.loadedAddress(), 0, 0); const char* path = imagePath(loadedImageCopy.image()); log_notifications("dyld: objc-init-notifier called with mh=%p, path=%s\n", loadedImageCopy.loadedAddress(), path); (*_objcNotifyInit)(path, loadedImageCopy.loadedAddress()); } // run all initializers in image runAllInitializersInImage(loadedImageCopy.image(), loadedImageCopy.loadedAddress()); // advance state to inited swapImageState(imageToInit, indexHint, LoadedImage::State::beingInited, LoadedImage::State::inited); } }); } void AllImages::runLibSystemInitializer(const LoadedImage& libSystem) { // run all initializers in libSystem.dylib runAllInitializersInImage(libSystem.image(), libSystem.loadedAddress()); // Note: during libSystem's initialization, libdyld_initializer() is called which copies _initialImages to _loadedImages // mark libSystem.dylib as being inited, so later recursive-init would re-run it for (LoadedImage& li : _loadedImages) { if ( li.loadedAddress() == libSystem.loadedAddress() ) { li.setState(LoadedImage::State::inited); break; } } } void AllImages::runAllInitializersInImage(const closure::Image* image, const MachOLoaded* ml) { image->forEachInitializer(ml, ^(const void* func) { Initializer initFunc = (Initializer)func; #if __has_feature(ptrauth_calls) initFunc = (Initializer)__builtin_ptrauth_sign_unauthenticated((void*)initFunc, 0, 0); #endif { ScopedTimer(DBG_DYLD_TIMING_STATIC_INITIALIZER, (uint64_t)ml, (uint64_t)func, 0); initFunc(NXArgc, NXArgv, environ, appleParams, _programVars); } log_initializers("dyld: called initialzer %p in %s\n", initFunc, image->path()); }); } const MachOLoaded* AllImages::dlopen(Diagnostics& diag, const char* path, bool rtldNoLoad, bool rtldLocal, bool rtldNoDelete, bool fromOFI, const void* callerAddress) { // quick check if path is in shared cache and already loaded if ( _dyldCacheAddress != nullptr ) { uint32_t dyldCacheImageIndex; if ( _dyldCacheAddress->hasImagePath(path, dyldCacheImageIndex) ) { uint64_t mTime; uint64_t inode; const MachOLoaded* mh = (MachOLoaded*)_dyldCacheAddress->getIndexedImageEntry(dyldCacheImageIndex, mTime, inode); // Note: we do not need readLock because this is within global dlopen lock for (const LoadedImage& li : _loadedImages) { if ( li.loadedAddress() == mh ) { return mh; } } } } __block closure::ImageNum callerImageNum = 0; STACK_ALLOC_ARRAY(LoadedImage, loadedList, 1024); for (const LoadedImage& li : _loadedImages) { loadedList.push_back(li); uint8_t permissions; if ( (callerImageNum == 0) && li.image()->containsAddress(callerAddress, li.loadedAddress(), &permissions) ) { callerImageNum = li.image()->imageNum(); } //fprintf(stderr, "mh=%p, image=%p, imageNum=0x%04X, path=%s\n", li.loadedAddress(), li.image(), li.image()->imageNum(), li.image()->path()); } uintptr_t alreadyLoadedCount = loadedList.count(); // make closure closure::ImageNum topImageNum = 0; const closure::DlopenClosure* newClosure; // First try with closures from the shared cache permitted. // Then try again with forcing a new closure for (bool canUseSharedCacheClosure : { true, false }) { closure::FileSystemPhysical fileSystem; closure::ClosureBuilder::AtPath atPathHanding = (_allowAtPaths ? closure::ClosureBuilder::AtPath::all : closure::ClosureBuilder::AtPath::onlyInRPaths); closure::ClosureBuilder cb(_nextImageNum, fileSystem, _dyldCacheAddress, true, closure::gPathOverrides, atPathHanding); newClosure = cb.makeDlopenClosure(path, _mainClosure, loadedList, callerImageNum, rtldNoLoad, canUseSharedCacheClosure, &topImageNum); if ( newClosure == closure::ClosureBuilder::sRetryDlopenClosure ) { log_apis(" dlopen: closure builder needs to retry: %s\n", path); assert(canUseSharedCacheClosure); continue; } if ( (newClosure == nullptr) && (topImageNum == 0) ) { if ( cb.diagnostics().hasError()) diag.error("%s", cb.diagnostics().errorMessage()); else if ( !rtldNoLoad ) diag.error("dlopen(): file not found: %s", path); return nullptr; } // save off next available ImageNum for use by next call to dlopen() _nextImageNum = cb.nextFreeImageNum(); break; } if ( newClosure != nullptr ) { // if new closure contains an ImageArray, add it to list if ( const closure::ImageArray* newArray = newClosure->images() ) { appendToImagesArray(newArray); } log_apis(" dlopen: made closure: %p\n", newClosure); } // if already loaded, just bump refCount and return if ( (newClosure == nullptr) && (topImageNum != 0) ) { for (LoadedImage& li : _loadedImages) { if ( li.image()->imageNum() == topImageNum ) { // is already loaded const MachOLoaded* topLoadAddress = li.loadedAddress(); if ( !li.image()->inDyldCache() ) incRefCount(topLoadAddress); log_apis(" dlopen: already loaded as '%s'\n", li.image()->path()); // if previously opened with RTLD_LOCAL, but now opened with RTLD_GLOBAL, unhide it if ( !rtldLocal && li.hideFromFlatSearch() ) li.setHideFromFlatSearch(false); // if called with RTLD_NODELETE, mark it as never-unload if ( rtldNoDelete ) li.markLeaveMapped(); return topLoadAddress; } } } // run loader to load all new images Loader loader(loadedList, _dyldCacheAddress, imagesArrays(), &dyld3::log_loads, &dyld3::log_segments, &dyld3::log_fixups, &dyld3::log_dofs); const closure::Image* topImage = closure::ImageArray::findImage(imagesArrays(), topImageNum); if ( newClosure == nullptr ) { if ( topImageNum < dyld3::closure::kLastDyldCacheImageNum ) log_apis(" dlopen: using image in dyld shared cache %p\n", topImage); else log_apis(" dlopen: using pre-built dlopen closure %p\n", topImage); } uintptr_t topIndex = loadedList.count(); LoadedImage topLoadedImage = LoadedImage::make(topImage); if ( rtldLocal && !topImage->inDyldCache() ) topLoadedImage.setHideFromFlatSearch(true); if ( rtldNoDelete && !topImage->inDyldCache() ) topLoadedImage.markLeaveMapped(); loader.addImage(topLoadedImage); // recursively load all dependents and fill in allImages array loader.completeAllDependents(diag, topIndex); if ( diag.hasError() ) return nullptr; loader.mapAndFixupAllImages(diag, _processDOFs, fromOFI, topIndex); if ( diag.hasError() ) return nullptr; const MachOLoaded* topLoadAddress = loadedList[topIndex].loadedAddress(); // bump dlopen refcount of image directly loaded if ( !topImage->inDyldCache() ) incRefCount(topLoadAddress); // tell gAllImages about new images const uint32_t newImageCount = (uint32_t)(loadedList.count() - alreadyLoadedCount); addImages(loadedList.subArray(alreadyLoadedCount, newImageCount)); // if closure adds images that override dyld cache, patch cache if ( newClosure != nullptr ) applyInterposingToDyldCache(newClosure); runImageNotifiers(loadedList.subArray(alreadyLoadedCount, newImageCount)); // run initializers runInitialzersBottomUp(topImage); return topLoadAddress; } void AllImages::appendToImagesArray(const closure::ImageArray* newArray) { _imagesArrays.push_back(newArray); } const Array<const closure::ImageArray*>& AllImages::imagesArrays() { return _imagesArrays.array(); } bool AllImages::isRestricted() const { return !_allowEnvPaths; } } // namespace dyld3 |