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libdyld/dyld_process_info.cpp dyld-960 dyld-1165.3
--- dyld/dyld-960/libdyld/dyld_process_info.cpp
+++ dyld/dyld-1165.3/libdyld/dyld_process_info.cpp
@@ -22,6 +22,9 @@
  * @APPLE_LICENSE_HEADER_END@
  */
 
+#include <TargetConditionals.h>
+#if !TARGET_OS_EXCLAVEKIT
+
 #include <dlfcn.h>
 #include <stdlib.h>
 #include <string.h>
@@ -35,13 +38,17 @@
 #include <libkern/OSAtomic.h>
 #include <mach-o/dyld_process_info.h>
 #include <mach-o/dyld_images.h>
+#include <mach-o/dyld_priv.h>
 
 #include "MachOFile.h"
+#include "DyldSharedCache.h"
 #include "dyld_process_info_internal.h"
 #include "Tracing.h"
-#include "DebuggerSupport.h"
 #include "DyldProcessConfig.h"
 
+#define BLEND_KERN_RETURN_LOCATION(kr, loc) (kr) = ((kr & 0x00ffffff) | loc<<24);
+
+#define IMAGE_COUNT_MAX 8192
 RemoteBuffer& RemoteBuffer::operator=(RemoteBuffer&& other) {
     std::swap(_localAddress, other._localAddress);
     std::swap(_size, other._size);
@@ -101,12 +108,13 @@
     // we are copying some memory in the middle of a mach-o that is on a USB drive that is disconnected after we perform
     // the mapping). Once we copy them into a local buffer the memory will be handled by the default pager instead of
     // potentially being backed by the mmap pager, and thus will be guaranteed not to mutate out from under us.
-    void* buffer = malloc(size);
+    void* buffer = malloc(size + 1);
     if (buffer == nullptr) {
         (void)vm_deallocate(mach_task_self(), (vm_address_t)localAddress, size);
         return std::make_pair(MACH_VM_MIN_ADDRESS, KERN_NO_SPACE);
     }
     memcpy(buffer, (void *)localAddress, size);
+    ((char*)buffer)[size] = 0; // Add a null terminator so strlcpy does not read base the end of the buffer.
     (void)vm_deallocate(mach_task_self(), (vm_address_t)localAddress, size);
     return std::make_pair((vm_address_t)buffer, KERN_SUCCESS);
 }
@@ -124,7 +132,8 @@
     // truncatable buffer we map is less than a single page. To be more general we would need to try repeatedly in a
     // loop.
     if (allow_truncation) {
-        size = PAGE_SIZE - remote_address%PAGE_SIZE;
+        // Manually set to 4096 instead of page size to deal with wierd issues involving 4k page arm64 binaries
+        size = 4096 - remote_address%4096;
         std::tie(localAddress, kr) = map(task, remote_address, size);
         if (kr == KERN_SUCCESS) return std::make_tuple(localAddress, size, kr);
     }
@@ -176,7 +185,7 @@
     template<typename T1, typename T2>
     static dyld_process_info_ptr make(task_t task, const T1& allImageInfo, uint64_t timestamp, kern_return_t* kr);
     template<typename T>
-    static dyld_process_info_ptr makeSuspended(task_t task, const T& allImageInfo, kern_return_t* kr);
+    static dyld_process_info_ptr makeSuspended(task_t task, const T& allImageInfo, uint64_t timestamp, kern_return_t* kr);
 
     std::atomic<uint32_t>&       retainCount() const { return _retainCount; }
     dyld_process_cache_info*     cacheInfo() const { return (dyld_process_cache_info*)(((char*)this) + _cacheInfoOffset); }
@@ -226,15 +235,14 @@
                                 dyld_process_info_base(dyld_platform_t platform, unsigned imageCount, unsigned aotImageCount, size_t totalSize);
     void*                       operator new (size_t, void* buf) { return buf; }
 
-    static bool                 inCache(uint64_t addr) { return (addr > SHARED_REGION_BASE) && (addr < SHARED_REGION_BASE+SHARED_REGION_SIZE); }
-    bool                        addImage(task_t task, bool sameCacheAsThisProcess, uint64_t imageAddress, uint64_t imagePath, const char* imagePathLocal);
-
-    bool                        addAotImage(dyld_aot_image_info_64 aotImageInfo);
+    kern_return_t               addImage(task_t task, bool sameCacheAsThisProcess, uint64_t sharedCacheStart, uint64_t sharedCacheEnd, uint64_t imageAddress, uint64_t imagePath, const char* imagePathLocal);
+
+    kern_return_t               addAotImage(dyld_aot_image_info_64 aotImageInfo);
 
     kern_return_t               addDyldImage(task_t task, uint64_t dyldAddress, uint64_t dyldPathAddress, const char* localPath);
 
     bool                        invalid() { return ((char*)_stringRevBumpPtr < (char*)_curSegment); }
-    const char*                 copyPath(task_t task, uint64_t pathAddr);
+    const char*                 copyPath(task_t task, kern_return_t* kr, uint64_t pathAddr);
     const char*                 addString(const char*, size_t);
     const char*                 copySegmentName(const char*);
 
@@ -269,13 +277,20 @@
     // char                     stringPool[]
 };
 
+static uint32_t addWithOverflowOrReturnZero(uint32_t a, uint32_t b)
+{
+    uint32_t result = 0;
+    assert( !__builtin_add_overflow(a, b, &result) );
+    return result;
+}
+
 dyld_process_info_base::dyld_process_info_base(dyld_platform_t platform, unsigned imageCount, unsigned aotImageCount, size_t totalSize)
  :  _retainCount(1), _cacheInfoOffset(sizeof(dyld_process_info_base)),
-    _aotCacheInfoOffset(sizeof(dyld_process_info_base) + sizeof(dyld_process_cache_info)),
-    _stateInfoOffset(sizeof(dyld_process_info_base) + sizeof(dyld_process_cache_info) + sizeof(dyld_process_aot_cache_info)),
-    _imageInfosOffset(sizeof(dyld_process_info_base) + sizeof(dyld_process_cache_info) + sizeof(dyld_process_aot_cache_info) + sizeof(dyld_process_state_info)),
-    _aotImageInfosOffset(sizeof(dyld_process_info_base) + sizeof(dyld_process_cache_info) + sizeof(dyld_process_aot_cache_info) + sizeof(dyld_process_state_info) + imageCount*sizeof(ImageInfo)),
-    _segmentInfosOffset(sizeof(dyld_process_info_base) + sizeof(dyld_process_cache_info) + sizeof(dyld_process_aot_cache_info) + sizeof(dyld_process_state_info) + imageCount*sizeof(ImageInfo) + aotImageCount*sizeof(dyld_aot_image_info_64)),
+    _aotCacheInfoOffset(_cacheInfoOffset + sizeof(dyld_process_cache_info)),
+    _stateInfoOffset(_aotCacheInfoOffset + sizeof(dyld_process_aot_cache_info)),
+    _imageInfosOffset(_stateInfoOffset + sizeof(dyld_process_state_info)),
+    _aotImageInfosOffset(addWithOverflowOrReturnZero(_imageInfosOffset, imageCount*sizeof(ImageInfo))),
+    _segmentInfosOffset(addWithOverflowOrReturnZero(_aotImageInfosOffset, aotImageCount*sizeof(dyld_aot_image_info_64))),
     _freeSpace(totalSize), _platform(platform),
     _firstImage((ImageInfo*)(((uint8_t*)this) + _imageInfosOffset)),
     _curImage((ImageInfo*)(((uint8_t*)this) + _imageInfosOffset)),
@@ -286,6 +301,7 @@
     _curSegmentIndex(0),
     _stringRevBumpPtr((char*)(this)+totalSize)
 {
+
 }
 
 template<typename T1, typename T2>
@@ -300,8 +316,16 @@
     }
 
     // Check if the process is suspended
-    if (allImageInfo.infoArrayChangeTimestamp == 0) {
-        result = dyld_process_info_base::makeSuspended<T1>(task, allImageInfo, kr);
+    bool shouldMakeSuspended = (allImageInfo.infoArrayChangeTimestamp == 0);
+    if ( !shouldMakeSuspended ) {
+        if ( (allImageInfo.infoArray == 0)
+            && (allImageInfo.sharedCacheBaseAddress != 0)
+            && ((uintptr_t)allImageInfo.dyldImageLoadAddress > allImageInfo.sharedCacheBaseAddress) )
+            shouldMakeSuspended = true;
+    }
+    if (shouldMakeSuspended) {
+        result = dyld_process_info_base::makeSuspended<T1>(task, allImageInfo,
+                                                           allImageInfo.infoArrayChangeTimestamp, kr);
         // If we have a result return it, otherwise rescan
         if (result) {
             // If it returned the process is suspended and there is nothing more to do
@@ -309,7 +333,9 @@
         }
         usleep(1000 * 50); // 50ms
         // Not exactly correct, but conveys that operation may succeed in the future
-        *kr = KERN_RESOURCE_SHORTAGE;
+        if (*kr == KERN_SUCCESS) {
+            *kr = KERN_RESOURCE_SHORTAGE;
+        }
         return  nullptr;
     }
 
@@ -324,7 +350,7 @@
     if (infoArray == 0) {
         usleep(1000 * 50); // 50ms
         // Not exactly correct, but conveys that operation may succeed in the future
-        *kr = KERN_RESOURCE_SHORTAGE;
+        *kr = KERN_UREFS_OVERFLOW;
         return  nullptr;
     };
 
@@ -332,28 +358,51 @@
     // terrible things that corrupt their own image lists and we need to stop clients from crashing
     // reading them. We can try to do something more advanced in the future. rdar://27446361
     uint32_t imageCount = allImageInfo.infoArrayCount;
-    imageCount = MIN(imageCount, 8192);
+    imageCount = MIN(imageCount, IMAGE_COUNT_MAX);
     size_t imageArraySize = imageCount * sizeof(T2);
+
+    uint64_t sharedCacheStart   = 0;
+    uint64_t sharedCacheEnd     = 0;
+    size_t   sharedCacheLength  = 0;
+    if ( const void* start = _dyld_get_shared_cache_range(&sharedCacheLength) ) {
+        sharedCacheStart = (uint64_t)start;
+        sharedCacheEnd = sharedCacheStart + (uint64_t)sharedCacheLength;
+    }
 
     withRemoteBuffer(task, infoArray, imageArraySize, false, kr, ^(void *buffer, size_t size) {
         // figure out how many path strings will need to be copied and their size
         T2* imageArray = (T2 *)buffer;
-        const dyld_all_image_infos* myInfo = (const dyld_all_image_infos*)dyld4::gDyld.allImageInfos;
-        bool sameCacheAsThisProcess = !allImageInfo.processDetachedFromSharedRegion
+        const dyld_all_image_infos* myInfo = (const dyld_all_image_infos*)dyld4::gDyld.allImageInfos;   // FIXME: should not need dyld_all_image_info
+        const bool sameCacheAsThisProcess = true
+            && (allImageInfo.sharedCacheBaseAddress != 0)
+            && (myInfo->sharedCacheBaseAddress != 0)
+            && !allImageInfo.processDetachedFromSharedRegion
             && !myInfo->processDetachedFromSharedRegion
             && ((memcmp(myInfo->sharedCacheUUID, &allImageInfo.sharedCacheUUID[0], 16) == 0)
             && (myInfo->sharedCacheSlide == allImageInfo.sharedCacheSlide));
         unsigned countOfPathsNeedingCopying = 0;
-        if ( sameCacheAsThisProcess ) {
-            for (uint32_t i=0; i < imageCount; ++i) {
-                if ( !inCache(imageArray[i].imageFilePath) )
-                    ++countOfPathsNeedingCopying;
-            }
-        }
-        else {
+        // If constexpr is basically superfluous, we only do it to avoid compiler warnings...
+        // The only time when sizeof(T2().imageFilePath) != sizeof(void*) is when a 64 bit process is introspecting a 32 bit process
+        // or vice versa, and in those cases sameCacheAsThisProcess will be false. The issue is the compiler can't know that which
+        // forces it to build the code, which results in the case from imageArray[i].imageFilePath to a (void*) to generate a warning.
+        // By using the constexpr check here we can elide compiling that case and the warning, which prevents -Werror failues.
+        if constexpr(sizeof(T2().imageFilePath) == sizeof(void*)) {
+            const DyldSharedCache* dyldCacheHeader = (DyldSharedCache*)sharedCacheStart;
+            if ( sameCacheAsThisProcess && dyldCacheHeader != nullptr) {
+                bool readOnly = false;
+                for (uint32_t i=0; i < imageCount; ++i) {
+                    if ( !dyldCacheHeader->inCache((void*)imageArray[i].imageFilePath, 1, readOnly) )
+                        ++countOfPathsNeedingCopying;
+                }
+            }
+            else {
+                countOfPathsNeedingCopying = imageCount+1;
+            }
+        } else {
             countOfPathsNeedingCopying = imageCount+1;
         }
         unsigned imageCountWithDyld = imageCount+1;
+        unsigned aotImageCount = MIN(allImageInfo.aotInfoCount, IMAGE_COUNT_MAX);
 
         // allocate result object
         size_t allocationSize = sizeof(dyld_process_info_base)
@@ -361,9 +410,13 @@
                                     + sizeof(dyld_process_aot_cache_info)
                                     + sizeof(dyld_process_state_info)
                                     + sizeof(ImageInfo)*(imageCountWithDyld)
-                                    + sizeof(dyld_aot_image_info_64)*(allImageInfo.aotInfoCount) // add the size necessary for aot info to this buffer
+                                    + sizeof(dyld_aot_image_info_64)*(aotImageCount) // add the size necessary for aot info to this buffer
                                     + sizeof(SegmentInfo)*imageCountWithDyld*10
                                     + countOfPathsNeedingCopying*PATH_MAX;
+
+        // Add 32KB of padding just in case there's some kind of overflow/corruption in building the buffer
+        allocationSize += 0x8000;
+
         void* storage = malloc(allocationSize);
         if (storage == nullptr) {
             *kr = KERN_NO_SPACE;
@@ -410,15 +463,14 @@
         // fill in info for dyld
         if ( allImageInfo.dyldPath != 0 ) {
             if ((*kr = info->addDyldImage(task, allImageInfo.dyldImageLoadAddress, allImageInfo.dyldPath, NULL))) {
-                *kr = KERN_FAILURE;
                 result = nullptr;
                 return;
             }
         }
         // fill in info for each image
         for (uint32_t i=0; i < imageCount; ++i) {
-            if (!info->addImage(task, sameCacheAsThisProcess, imageArray[i].imageLoadAddress, imageArray[i].imageFilePath, NULL)) {
-                *kr = KERN_FAILURE;
+            *kr =  info->addImage(task, sameCacheAsThisProcess, sharedCacheStart, sharedCacheEnd, imageArray[i].imageLoadAddress, imageArray[i].imageFilePath, NULL);
+            if (*kr != KERN_SUCCESS) {
                 result = nullptr;
                 return;
             }
@@ -443,8 +495,7 @@
         withRemoteBuffer(task, aotImageArray, aotImageArraySize, false, kr, ^(void *buffer, size_t size) {
             dyld_aot_image_info_64* imageArray = (dyld_aot_image_info_64*)buffer;
             for (uint32_t i = 0; i < aotImageCount; i++) {
-                if (!result->addAotImage(imageArray[i])) {
-                    *kr = KERN_FAILURE;
+                if ((*kr = result->addAotImage(imageArray[i]))) {
                     result = nullptr;
                     return;
                 }
@@ -455,7 +506,8 @@
 }
 
 template<typename T>
-dyld_process_info_ptr dyld_process_info_base::makeSuspended(task_t task, const T& allImageInfo, kern_return_t* kr)
+dyld_process_info_ptr dyld_process_info_base::makeSuspended(task_t task, const T& allImageInfo,
+                                                            uint64_t timestamp, kern_return_t* kr)
 {
     pid_t   pid;
     if ((*kr = pid_for_task(task, &pid))) {
@@ -465,12 +517,24 @@
     mach_task_basic_info ti;
     mach_msg_type_number_t count = MACH_TASK_BASIC_INFO_COUNT;
     if ((*kr = task_info(task, MACH_TASK_BASIC_INFO, (task_info_t)&ti, &count))) {
+        *kr = KERN_NO_SPACE;
         return  nullptr;
     }
 
     // The task is not suspended, exit
     if (ti.suspend_count == 0) {
-        return  nullptr;
+        // Even if the process is not suspended it might never make forward progress. This is because it might be a corpse, which
+        // despite not being runnable may not have the suspended flag set. The only way to tell if it is a corpse is to to try to
+        // map the corpse data, even though we don't actually need the corpse data
+        mach_vm_address_t kcd_addr_begin = 0;
+        mach_vm_size_t kcd_size = 0;
+        *kr = task_map_corpse_info_64(mach_task_self(), task, &kcd_addr_begin, &kcd_size);
+        if (*kr != KERN_SUCCESS) {
+            // Not a corpse, so forward progress is possible. Return so that make() can pause and retry
+            return nullptr;
+        }
+        // It is a corpse. Unmap the corpse info and keep scavenging the suspended process
+        vm_deallocate(mach_task_self(), (vm_address_t)kcd_addr_begin, (vm_size_t)kcd_size);
     }
 
     __block unsigned        imageCount = 0;  // main executable and dyld
@@ -481,7 +545,10 @@
     __block char *          dyldPath = &dyldPathBuffer[0];
     __block char *          mainExecutablePath = &mainExecutablePathBuffer[0];
     __block dyld3::Platform platformID = dyld3::Platform::unknown;
-    mach_vm_size_t      size;
+    mach_vm_size_t          size;
+    dyldPathBuffer[0]           = '\0';
+    mainExecutablePathBuffer[0] = '\0';
+
     for (mach_vm_address_t address = 0; ; address += size) {
         vm_region_basic_info_data_64_t  info;
         mach_port_t                     objectName;
@@ -500,16 +567,18 @@
                 if ( mhBuffer.filetype == MH_EXECUTE ) {
                     mainExecutableAddress = address;
                     int len = proc_regionfilename(pid, mainExecutableAddress, mainExecutablePath, PATH_MAX);
-                    if ( len != 0 ) {
-                        mainExecutablePath[len] = '\0';
+                    // explicitly clear the path if call failed
+                    if ( len <= 0 ) {
+                        strlcpy(mainExecutablePath, "/main_executable_path_missing", PATH_MAX);
                     }
                     ++imageCount;
                 }
                 else if ( mhBuffer.filetype == MH_DYLINKER ) {
                     dyldAddress = address;
                     int len = proc_regionfilename(pid, dyldAddress, dyldPath, PATH_MAX);
-                    if ( len != 0 ) {
-                        dyldPath[len] = '\0';
+                    // explicitly clear the path if call failed
+                    if ( len <= 0 ) {
+                        strlcpy(dyldPath, "/dyld_path_missing", PATH_MAX);
                     }
                     ++imageCount;
                 }
@@ -519,6 +588,15 @@
     //fprintf(stderr, "dyld: addr=0x%llX, path=%s\n", dyldAddress, dyldPathBuffer);
     //fprintf(stderr, "app:  addr=0x%llX, path=%s\n", mainExecutableAddress, mainExecutablePathBuffer);
 
+    // fill in info for dyld
+    if ( dyldAddress == 0 ) {
+        // if dyld was not found in vm walk, then we've switched to the dyld in the cache
+        dyldAddress = allImageInfo.dyldImageLoadAddress;
+        strcpy(dyldPathBuffer, "/usr/lib/dyld");
+        ++imageCount;
+    }
+
+    imageCount = MIN(imageCount, IMAGE_COUNT_MAX);
     // explicitly set aot image count to 0 in the suspended case
     unsigned aotImageCount = 0;
 
@@ -551,12 +629,11 @@
     aotCacheInfo->cacheBaseAddress = 0;
 
     dyld_process_state_info* stateInfo = obj->stateInfo();
-    stateInfo->timestamp           = 0;
+    stateInfo->timestamp           = timestamp;
     stateInfo->imageCount          = imageCount;
     stateInfo->initialImageCount   = imageCount;
     stateInfo->dyldState           = dyld_process_state_not_started;
 
-    // fill in info for dyld
     if ( dyldAddress != 0 ) {
         if ((*kr = obj->addDyldImage(task, dyldAddress, 0, dyldPath))) {
             return nullptr;
@@ -565,22 +642,13 @@
 
     // fill in info for each image
     if ( mainExecutableAddress != 0 ) {
-        if (!obj->addImage(task, false, mainExecutableAddress, 0, mainExecutablePath)) {
+        if ((*kr = obj->addImage(task, false, 0, 0, mainExecutableAddress, 0, mainExecutablePath))) {
             return nullptr;
         }
     }
 
-    if (allImageInfo.infoArrayChangeTimestamp != 0) {
-        return  nullptr;
-    }
-
-    count = MACH_TASK_BASIC_INFO_COUNT;
-    if ((*kr = task_info(task, MACH_TASK_BASIC_INFO, (task_info_t)&ti, &count))) {
-        return  nullptr;
-    }
-
-    // The task is not suspended, exit
-    if (ti.suspend_count == 0) {
+    if (allImageInfo.infoArrayChangeTimestamp != timestamp) {
+        *kr = KERN_INVALID_VALUE;
         return  nullptr;
     }
 
@@ -599,43 +667,56 @@
     return _stringRevBumpPtr;
 }
 
-const char* dyld_process_info_base::copyPath(task_t task, uint64_t stringAddressInTask)
+const char* dyld_process_info_base::copyPath(task_t task, kern_return_t *kr, uint64_t stringAddressInTask)
 {
     __block const char* retval = "";
-    withRemoteBuffer(task, stringAddressInTask, PATH_MAX, true, nullptr, ^(void *buffer, size_t size) {
+    withRemoteBuffer(task, stringAddressInTask, PATH_MAX, true, kr, ^(void *buffer, size_t size) {
         retval = addString(static_cast<const char *>(buffer), size);
     });
     return retval;
 }
 
-bool dyld_process_info_base::addImage(task_t task, bool sameCacheAsThisProcess, uint64_t imageAddress, uint64_t imagePath, const char* imagePathLocal)
-{
+kern_return_t dyld_process_info_base::addImage(task_t task, bool sameCacheAsThisProcess, uint64_t sharedCacheStart, uint64_t sharedCacheEnd, uint64_t imageAddress, uint64_t imagePath, const char* imagePathLocal)
+{
+    kern_return_t kr = KERN_SUCCESS;
+
+    const DyldSharedCache* dyldCacheHeader = (DyldSharedCache*)sharedCacheStart;
+    bool readOnly = false;
     _curImage->loadAddress = imageAddress;
     _curImage->segmentStartIndex = _curSegmentIndex;
     if ( imagePathLocal != NULL ) {
         _curImage->path = addString(imagePathLocal, PATH_MAX);
-    } else if ( sameCacheAsThisProcess && inCache(imagePath) ) {
+    } else if ( sameCacheAsThisProcess && dyldCacheHeader != nullptr && dyldCacheHeader->inCache((void*)imagePath, 1, readOnly) ) {
         _curImage->path = (const char*)imagePath;
     } else if (imagePath) {
-        _curImage->path = copyPath(task, imagePath);
+        _curImage->path = copyPath(task, &kr, imagePath);
+        if ( kr != KERN_SUCCESS ) {
+            // Could not copy path, return early
+            _curImage->path = "";
+            BLEND_KERN_RETURN_LOCATION(kr, 0xe9);
+            return kr;
+        }
     } else {
         _curImage->path = "";
     }
 
-    if ( sameCacheAsThisProcess && inCache(imageAddress) ) {
+    if ( sameCacheAsThisProcess && dyldCacheHeader != nullptr && dyldCacheHeader->inCache((void*)imageAddress, 32*1024, readOnly) ) {
         addInfoFromLoadCommands((mach_header*)imageAddress, imageAddress, 32*1024);
-    } else if (addInfoFromRemoteLoadCommands(task, imageAddress) != KERN_SUCCESS) {
-        // The image is not here, return early
-        return false;
+    } else {
+        kr = addInfoFromRemoteLoadCommands(task, imageAddress);
+        if (kr != KERN_SUCCESS) {
+            // The image is not here, return early
+            return kr;
+        }
     }
     _curImage->segmentsCount = _curSegmentIndex - _curImage->segmentStartIndex;
     _curImage++;
-    return true;
-}
-
-bool dyld_process_info_base::addAotImage(dyld_aot_image_info_64 aotImageInfo) {
+    return kr;
+}
+
+kern_return_t dyld_process_info_base::addAotImage(dyld_aot_image_info_64 aotImageInfo) {
     if (!reserveSpace(sizeof(dyld_aot_image_info_64))) {
-        return false;
+        return KERN_NO_SPACE;
     }
     _curAotImage->x86LoadAddress = aotImageInfo.x86LoadAddress;
     _curAotImage->aotLoadAddress = aotImageInfo.aotLoadAddress;
@@ -643,7 +724,7 @@
     memcpy(_curAotImage->aotImageKey, aotImageInfo.aotImageKey, sizeof(aotImageInfo.aotImageKey));
 
     _curAotImage++;
-    return true;
+    return KERN_SUCCESS;
 }
 
 kern_return_t dyld_process_info_base::addInfoFromRemoteLoadCommands(task_t task, uint64_t remoteMH) {
@@ -652,7 +733,7 @@
     __block bool done = false;
 
     //Since the minimum we can reasonably map is a page, map that.
-    withRemoteBuffer(task, remoteMH, PAGE_SIZE, true, &kr, ^(void * buffer, size_t size) {
+    withRemoteBuffer(task, remoteMH, 4096, true, &kr, ^(void * buffer, size_t size) {
         if (size > sizeof(mach_header)) {
             const mach_header* mh = (const mach_header*)buffer;
             headerPagesSize = sizeof(mach_header) + mh->sizeofcmds;
@@ -685,9 +766,12 @@
         _curImage->path = addString(localPath, PATH_MAX);
     }
     else {
-        _curImage->path = copyPath(task, dyldPathAddress);
-        if ( kr != KERN_SUCCESS)
+        _curImage->path = copyPath(task, &kr, dyldPathAddress);
+        if ( kr != KERN_SUCCESS) {
+            _curImage->path = "";
+            BLEND_KERN_RETURN_LOCATION(kr, 0xea);
             return kr;
+        }
     }
 
     kr = addInfoFromRemoteLoadCommands(task, dyldAddress);
@@ -696,7 +780,7 @@
 
     _curImage->segmentsCount = _curSegmentIndex - _curImage->segmentStartIndex;
     _curImage++;
-    return KERN_SUCCESS;
+    return kr;
 }
 
 
@@ -841,6 +925,12 @@
             }
         });
         if (*kr == KERN_SUCCESS) { break; }
+        // possible that dyld moved, causing imageinfo reads to fail, so get TASK_DYLD_INFO again
+        task_dyld_info_data_t task_dyld_info2;
+        mach_msg_type_number_t count2 = TASK_DYLD_INFO_COUNT;
+        if ( task_info(task, TASK_DYLD_INFO, (task_info_t)&task_dyld_info2, &count2) == KERN_SUCCESS ) {
+            task_dyld_info = task_dyld_info2;
+        }
     }
     return  result;
 }
@@ -891,5 +981,6 @@
     info->forEachSegment(machHeaderAddress, callback);
 }
 
-
-
+#endif // !TARGET_OS_EXCLAVEKIT
+
+