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--- dyld/dyld-132.13/src/ImageLoaderMachOClassic.cpp
+++ dyld/dyld-195.5/src/ImageLoaderMachOClassic.cpp
@@ -1,6 +1,6 @@
/* -*- mode: C++; c-basic-offset: 4; tab-width: 4 -*-
*
- * Copyright (c) 2004-2008 Apple Inc. All rights reserved.
+ * Copyright (c) 2004-2010 Apple Inc. All rights reserved.
*
* @APPLE_LICENSE_HEADER_START@
*
@@ -106,11 +106,12 @@
image->setSlide(slide);
// for PIE record end of program, to know where to start loading dylibs
- if ( (mh->flags & MH_PIE) && !context.noPIE )
+ if ( slide != 0 )
fgNextPIEDylibAddress = (uintptr_t)image->getEnd();
image->instantiateFinish(context);
-
+ image->setMapped(context);
+
#if __i386__
// kernel may have mapped in __IMPORT segment read-only, we need it read/write to do binding
if ( image->fReadOnlyImportSegment ) {
@@ -138,21 +139,26 @@
// create image by mapping in a mach-o file
ImageLoaderMachOClassic* ImageLoaderMachOClassic::instantiateFromFile(const char* path, int fd, const uint8_t* fileData,
uint64_t offsetInFat, uint64_t lenInFat, const struct stat& info,
- unsigned int segCount, unsigned int libCount, const LinkContext& context)
+ unsigned int segCount, unsigned int libCount,
+ const struct linkedit_data_command* codeSigCmd, const LinkContext& context)
{
ImageLoaderMachOClassic* image = ImageLoaderMachOClassic::instantiateStart((macho_header*)fileData, path, segCount, libCount);
try {
// record info about file
image->setFileInfo(info.st_dev, info.st_ino, info.st_mtime);
+ #if CODESIGNING_SUPPORT
+ // if this image is code signed, let kernel validate signature before mapping any pages from image
+ if ( codeSigCmd != NULL )
+ image->loadCodeSignature(codeSigCmd, fd, offsetInFat);
+ #endif
+
// mmap segments
image->mapSegmentsClassic(fd, offsetInFat, lenInFat, info.st_size, context);
- #if CODESIGNING_SUPPORT
- // if this code is signed, validate the signature before accessing any mapped pages
- image->loadCodeSignature(fileData, fd, offsetInFat);
- #endif
-
+ // finish up
+ image->instantiateFinish(context);
+
// if path happens to be same as in LC_DYLIB_ID load command use that, otherwise malloc a copy of the path
const char* installName = image->getInstallPath();
if ( (installName != NULL) && (strcmp(installName, path) == 0) && (path[0] == '/') )
@@ -168,13 +174,14 @@
else
image->setPath(path);
+ // make sure path is stable before recording in dyld_all_image_infos
+ image->setMapped(context);
+
// pre-fetch content of __DATA segment for faster launches
// don't do this on prebound images or if prefetching is disabled
if ( !context.preFetchDisabled && !image->isPrebindable())
image->preFetchDATA(fd, offsetInFat, context);
- // finish up
- image->instantiateFinish(context);
}
catch (...) {
// ImageLoader::setMapped() can throw an exception to block loading of image
@@ -187,7 +194,7 @@
}
// create image by using cached mach-o file
-ImageLoaderMachOClassic* ImageLoaderMachOClassic::instantiateFromCache(const macho_header* mh, const char* path, const struct stat& info,
+ImageLoaderMachOClassic* ImageLoaderMachOClassic::instantiateFromCache(const macho_header* mh, const char* path, long slide, const struct stat& info,
unsigned int segCount, unsigned int libCount, const LinkContext& context)
{
ImageLoaderMachOClassic* image = ImageLoaderMachOClassic::instantiateStart(mh, path, segCount, libCount);
@@ -208,6 +215,7 @@
}
image->instantiateFinish(context);
+ image->setMapped(context);
}
catch (...) {
// ImageLoader::setMapped() can throw an exception to block loading of image
@@ -240,6 +248,7 @@
image->setPath(moduleName);
image->instantiateFinish(context);
+ image->setMapped(context);
}
catch (...) {
// ImageLoader::setMapped() can throw an exception to block loading of image
@@ -278,9 +287,6 @@
{
// now that segments are mapped in, get real fMachOData, fLinkEditBase, and fSlide
this->parseLoadCmds();
-
- // notify state change
- this->setMapped(context);
}
ImageLoaderMachOClassic::~ImageLoaderMachOClassic()
@@ -298,8 +304,8 @@
ImageLoader* ImageLoaderMachOClassic::libImage(unsigned int libIndex) const
{
const uintptr_t* images = ((uintptr_t*)(((uint8_t*)this) + sizeof(ImageLoaderMachOClassic) + fSegmentsCount*sizeof(uint32_t)));
- // mask off low bit
- return (ImageLoader*)(images[libIndex] & (-2));
+ // mask off low bits
+ return (ImageLoader*)(images[libIndex] & (-4));
}
bool ImageLoaderMachOClassic::libReExported(unsigned int libIndex) const
@@ -309,13 +315,22 @@
return ((images[libIndex] & 1) != 0);
}
-
-void ImageLoaderMachOClassic::setLibImage(unsigned int libIndex, ImageLoader* image, bool reExported)
+bool ImageLoaderMachOClassic::libIsUpward(unsigned int libIndex) const
+{
+ const uintptr_t* images = ((uintptr_t*)(((uint8_t*)this) + sizeof(ImageLoaderMachOClassic) + fSegmentsCount*sizeof(uint32_t)));
+ // upward flag is second bit
+ return ((images[libIndex] & 2) != 0);
+}
+
+
+void ImageLoaderMachOClassic::setLibImage(unsigned int libIndex, ImageLoader* image, bool reExported, bool upward)
{
uintptr_t* images = ((uintptr_t*)(((uint8_t*)this) + sizeof(ImageLoaderMachOClassic) + fSegmentsCount*sizeof(uint32_t)));
uintptr_t value = (uintptr_t)image;
if ( reExported )
value |= 1;
+ if ( upward )
+ value |= 2;
images[libIndex] = value;
}
@@ -506,9 +521,12 @@
return ImageLoaderMachO::mapSegments(fd, offsetInFat, lenInFat, fileLen, context);
#if SPLIT_SEG_SHARED_REGION_SUPPORT
- // try to map into shared region at preferred address
- if ( mapSplitSegDylibInfoSharedRegion(fd, offsetInFat, lenInFat, fileLen, context) == 0)
- return;
+ // don't map split-seg dylibs into shared region if shared cache is in use
+ if ( ! context.dyldLoadedAtSameAddressNeededBySharedCache ) {
+ // try to map into shared region at preferred address
+ if ( mapSplitSegDylibInfoSharedRegion(fd, offsetInFat, lenInFat, fileLen, context) == 0)
+ return;
+ }
// if there is a problem, fall into case where we map file somewhere outside the shared region
#endif
@@ -779,6 +797,7 @@
void ImageLoaderMachOClassic::rebase(const LinkContext& context)
{
+ CRSetCrashLogMessage2(this->getPath());
register const uintptr_t slide = this->fSlide;
const uintptr_t relocBase = this->getRelocBase();
@@ -885,6 +904,7 @@
// update stats
fgTotalRebaseFixups += fDynamicInfo->nlocrel;
+ CRSetCrashLogMessage2(NULL);
}
@@ -986,7 +1006,7 @@
}
-uintptr_t ImageLoaderMachOClassic::exportedSymbolAddress(const Symbol* symbol) const
+uintptr_t ImageLoaderMachOClassic::exportedSymbolAddress(const LinkContext& context, const Symbol* symbol, bool runResolver) const
{
const struct macho_nlist* sym = (macho_nlist*)symbol;
uintptr_t result = sym->n_value + fSlide;
@@ -1066,9 +1086,9 @@
return false;
}
-uintptr_t ImageLoaderMachOClassic::getSymbolAddress(const macho_nlist* sym, const LinkContext& context) const
-{
- return ImageLoaderMachO::getSymbolAddress((Symbol*)sym, this, context);
+uintptr_t ImageLoaderMachOClassic::getSymbolAddress(const macho_nlist* sym, const LinkContext& context, bool runResolver) const
+{
+ return ImageLoaderMachO::getSymbolAddress((Symbol*)sym, this, context, runResolver);
}
uintptr_t ImageLoaderMachOClassic::resolveUndefined(const LinkContext& context, const struct macho_nlist* undefinedSymbol,
@@ -1085,7 +1105,7 @@
// flat lookup
if ( ((undefinedSymbol->n_type & N_PEXT) != 0) && ((undefinedSymbol->n_type & N_TYPE) == N_SECT) ) {
// is a multi-module private_extern internal reference that the linker did not optimize away
- uintptr_t addr = this->getSymbolAddress(undefinedSymbol, context);
+ uintptr_t addr = this->getSymbolAddress(undefinedSymbol, context, false);
*foundIn = this;
return addr;
}
@@ -1107,7 +1127,7 @@
// if reference is weak_import, then it is ok, just return 0
return 0;
}
- throwSymbolNotFound(symbolName, this->getPath(), "flat namespace");
+ throwSymbolNotFound(context, symbolName, this->getPath(), "flat namespace");
}
else {
// symbol requires searching images with coalesced symbols (not done during prebinding)
@@ -1118,14 +1138,14 @@
this->addDynamicReference(*foundIn);
return (*foundIn)->getExportedSymbolAddress(sym, context, this);
}
- //throwSymbolNotFound(symbolName, this->getPath(), "coalesced namespace");
+ //throwSymbolNotFound(context, symbolName, this->getPath(), "coalesced namespace");
//dyld::log("dyld: coalesced symbol %s not found in any coalesced image, falling back to two-level lookup", symbolName);
}
// if this is a real definition (not an undefined symbol) there is no ordinal
if ( (undefinedSymbol->n_type & N_TYPE) == N_SECT ) {
// static linker should never generate this case, but if it does, do something sane
- uintptr_t addr = this->getSymbolAddress(undefinedSymbol, context);
+ uintptr_t addr = this->getSymbolAddress(undefinedSymbol, context, false);
*foundIn = this;
return addr;
}
@@ -1152,7 +1172,7 @@
if ( context.flatExportFinder(symbolName, &sym, foundIn) )
return (*foundIn)->getExportedSymbolAddress(sym, context, this);
- throwSymbolNotFound(symbolName, this->getPath(), "dynamic lookup");
+ throwSymbolNotFound(context, symbolName, this->getPath(), "dynamic lookup");
}
else if ( ord <= libraryCount() ) {
target = libImage(ord-1);
@@ -1178,7 +1198,7 @@
else if ( (undefinedSymbol->n_type & N_PEXT) != 0 ) {
// don't know why the static linker did not eliminate the internal reference to a private extern definition
*foundIn = this;
- return this->getSymbolAddress(undefinedSymbol, context);
+ return this->getSymbolAddress(undefinedSymbol, context, false);
}
else if ( (undefinedSymbol->n_desc & N_WEAK_REF) != 0 ) {
// if definition not found and reference is weak return 0
@@ -1186,7 +1206,7 @@
}
// nowhere to be found
- throwSymbolNotFound(symbolName, this->getPath(), target->getPath());
+ throwSymbolNotFound(context, symbolName, this->getPath(), target->getPath());
}
}
@@ -1412,7 +1432,7 @@
return targetAddr;
}
-uintptr_t ImageLoaderMachOClassic::doBindFastLazySymbol(uint32_t lazyBindingInfoOffset, const LinkContext& context)
+uintptr_t ImageLoaderMachOClassic::doBindFastLazySymbol(uint32_t lazyBindingInfoOffset, const LinkContext& context, void (*lock)(), void (*unlock)())
{
throw "compressed LINKEDIT lazy binder called with classic LINKEDIT";
}
@@ -1557,7 +1577,15 @@
}
const struct macho_nlist* sym = &fSymbolTable[symbol_index];
//dyld::log("getAddressCoalIterator() => 0x%llX, %s symbol_index=%d, in %s\n", (uint64_t)(sym->n_value + fSlide), &fStrings[sym->n_un.n_strx], symbol_index, this->getPath());
+#if __arm__
+ // processor assumes code address with low bit set is thumb
+ if (sym->n_desc & N_ARM_THUMB_DEF)
+ return (sym->n_value | 1) + fSlide ;
+ else
+ return sym->n_value + fSlide;
+#else
return sym->n_value + fSlide;
+#endif
}
@@ -1622,7 +1650,7 @@
#if __arm__
// if weak and thumb subtract off extra thumb bit
if ( (undefinedSymbol->n_desc & N_ARM_THUMB_DEF) != 0 )
- addend += 1;
+ addend &= -2;
#endif
}
}
@@ -1645,6 +1673,11 @@
// to be definition address plus addend
//dyld::log("weak def, initialValue=0x%lX, undefAddr=0x%lX\n", initialValue, undefinedSymbol->n_value+fSlide);
addend = initialValue - (undefinedSymbol->n_value + fSlide);
+ #if __arm__
+ // if weak and thumb subtract off extra thumb bit
+ if ( (undefinedSymbol->n_desc & N_ARM_THUMB_DEF) != 0 )
+ addend &= -2;
+ #endif
}
else {
// nothing fixed up yet, addend is just initial value
@@ -1905,6 +1938,7 @@
void ImageLoaderMachOClassic::doBind(const LinkContext& context, bool forceLazysBound)
{
+ CRSetCrashLogMessage2(this->getPath());
#if __i386__
this->initializeLazyStubs(context);
#endif
@@ -1918,6 +1952,12 @@
// no valid prebinding, so bind symbols.
// values bound by name are stored two different ways in classic mach-o:
+ #if TEXT_RELOC_SUPPORT
+ // if there are __TEXT fixups, temporarily make __TEXT writable
+ if ( fTextSegmentBinds )
+ this->makeTextSegmentWritable(context, true);
+ #endif
+
// 1) external relocations are used for data initialized to external symbols
this->doBindExternalRelocations(context);
@@ -1925,10 +1965,17 @@
// if this image is in the shared cache, there is no way to reset the lazy pointers, so bind them now
this->bindIndirectSymbolPointers(context, true, forceLazysBound || fInSharedCache);
+ #if TEXT_RELOC_SUPPORT
+ // if there were __TEXT fixups, restore write protection
+ if ( fTextSegmentBinds )
+ this->makeTextSegmentWritable(context, false);
+ #endif
}
// set up dyld entry points in image
this->setupLazyPointerHandler(context);
+
+ CRSetCrashLogMessage2(NULL);
}
void ImageLoaderMachOClassic::doBindJustLazies(const LinkContext& context)
@@ -1936,6 +1983,100 @@
// some API called requested that all lazy pointers in this image be force bound
this->bindIndirectSymbolPointers(context, false, true);
}
+
+void ImageLoaderMachOClassic::doInterpose(const LinkContext& context)
+{
+ if ( context.verboseInterposing )
+ dyld::log("dyld: interposing %lu tuples onto: %s\n", fgInterposingTuples.size(), this->getPath());
+
+ // scan indirect symbols
+ const uint32_t cmd_count = ((macho_header*)fMachOData)->ncmds;
+ const struct load_command* const cmds = (struct load_command*)&fMachOData[sizeof(macho_header)];
+ const struct load_command* cmd = cmds;
+ for (uint32_t i = 0; i < cmd_count; ++i) {
+ switch (cmd->cmd) {
+ case LC_SEGMENT_COMMAND:
+ {
+ const struct macho_segment_command* seg = (struct macho_segment_command*)cmd;
+ const struct macho_section* const sectionsStart = (struct macho_section*)((char*)seg + sizeof(struct macho_segment_command));
+ const struct macho_section* const sectionsEnd = §ionsStart[seg->nsects];
+ for (const struct macho_section* sect=sectionsStart; sect < sectionsEnd; ++sect) {
+ const uint8_t type = sect->flags & SECTION_TYPE;
+ if ( (type == S_NON_LAZY_SYMBOL_POINTERS) || (type == S_LAZY_SYMBOL_POINTERS) ) {
+ const uint32_t pointerCount = sect->size / sizeof(uintptr_t);
+ uintptr_t* const symbolPointers = (uintptr_t*)(sect->addr + fSlide);
+ for (uint32_t pointerIndex=0; pointerIndex < pointerCount; ++pointerIndex) {
+ for (std::vector<InterposeTuple>::iterator it=fgInterposingTuples.begin(); it != fgInterposingTuples.end(); it++) {
+ // replace all references to 'replacee' with 'replacement'
+ if ( (symbolPointers[pointerIndex] == it->replacee) && (this != it->replacementImage) ) {
+ if ( context.verboseInterposing ) {
+ dyld::log("dyld: interposing: at %p replace 0x%lX with 0x%lX in %s\n",
+ &symbolPointers[pointerIndex], it->replacee, it->replacement, this->getPath());
+ }
+ symbolPointers[pointerIndex] = it->replacement;
+ }
+ }
+ }
+ }
+ #if __i386__
+ // i386 has special self-modifying stubs that might be prebound to "JMP rel32" that need checking
+ else if ( (type == S_SYMBOL_STUBS) && ((sect->flags & S_ATTR_SELF_MODIFYING_CODE) != 0) && (sect->reserved2 == 5) ) {
+ // check each jmp entry in this section
+ uint8_t* start = (uint8_t*)(sect->addr + this->fSlide);
+ uint8_t* end = start + sect->size;
+ for (uint8_t* entry = start; entry < end; entry += 5) {
+ if ( entry[0] == 0xE9 ) { // 0xE9 == JMP
+ uint32_t rel32 = *((uint32_t*)&entry[1]); // assume unaligned load of uint32_t is ok
+ uint32_t target = (uint32_t)&entry[5] + rel32;
+ for (std::vector<InterposeTuple>::iterator it=fgInterposingTuples.begin(); it != fgInterposingTuples.end(); it++) {
+ // replace all references to 'replacee' with 'replacement'
+ if ( (it->replacee == target) && (this != it->replacementImage) ) {
+ if ( context.verboseInterposing ) {
+ dyld::log("dyld: interposing: at %p replace JMP 0x%lX with JMP 0x%lX in %s\n",
+ &entry[1], it->replacee, it->replacement, this->getPath());
+ }
+ uint32_t newRel32 = it->replacement - (uint32_t)&entry[5];
+ *((uint32_t*)&entry[1]) = newRel32; // assume unaligned store of uint32_t is ok
+ }
+ }
+ }
+ }
+ }
+ #endif
+ }
+ }
+ break;
+ }
+ cmd = (const struct load_command*)(((char*)cmd)+cmd->cmdsize);
+ }
+
+ // scan external relocations
+ const uintptr_t relocBase = this->getRelocBase();
+ const relocation_info* const relocsStart = (struct relocation_info*)(&fLinkEditBase[fDynamicInfo->extreloff]);
+ const relocation_info* const relocsEnd = &relocsStart[fDynamicInfo->nextrel];
+ for (const relocation_info* reloc=relocsStart; reloc < relocsEnd; ++reloc) {
+ if (reloc->r_length == RELOC_SIZE) {
+ switch(reloc->r_type) {
+ case POINTER_RELOC:
+ {
+ uintptr_t* location = ((uintptr_t*)(reloc->r_address + relocBase));
+ for (std::vector<InterposeTuple>::iterator it=fgInterposingTuples.begin(); it != fgInterposingTuples.end(); it++) {
+ // replace all references to 'replacee' with 'replacement'
+ if ( (*location == it->replacee) && (this != it->replacementImage) ) {
+ if ( context.verboseInterposing ) {
+ dyld::log("dyld: interposing: at %p replace 0x%lX with 0x%lX in %s\n",
+ location, it->replacee, it->replacement, this->getPath());
+ }
+ *location = it->replacement;
+ }
+ }
+ }
+ break;
+ }
+ }
+ }
+}
+
const char* ImageLoaderMachOClassic::findClosestSymbol(const void* addr, const void** closestAddr) const
{
@@ -1970,7 +2111,14 @@
}
}
if ( bestSymbol != NULL ) {
+#if __arm__
+ if (bestSymbol->n_desc & N_ARM_THUMB_DEF)
+ *closestAddr = (void*)((bestSymbol->n_value | 1) + fSlide);
+ else
+ *closestAddr = (void*)(bestSymbol->n_value + fSlide);
+#else
*closestAddr = (void*)(bestSymbol->n_value + fSlide);
+#endif
return &fStrings[bestSymbol->n_un.n_strx];
}
return NULL;