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--- dyld/dyld-44.4/src/ImageLoaderMachO.cpp
+++ dyld/dyld-43/src/ImageLoaderMachO.cpp
@@ -316,38 +316,6 @@
= 0;
#endif
-static int
-_shared_region_map_file_with_mmap(
- int fd, // file descriptor to map into shared region
- unsigned int regionCount, // number of entres in array of regions
- const _shared_region_mapping_np regions[]) // the array of regions to map
-{
- // map in each region
- for(unsigned int i=0; i < regionCount; ++i) {
- void* mmapAddress = (void*)(uintptr_t)(regions[i].address);
- size_t size = regions[i].size;
- if ( (regions[i].init_prot & VM_PROT_ZF) != 0 ) {
- // do nothing already vm_allocate() which zero fills
- }
- else {
- int protection = 0;
- if ( regions[i].init_prot & VM_PROT_EXECUTE )
- protection |= PROT_EXEC;
- if ( regions[i].init_prot & VM_PROT_READ )
- protection |= PROT_READ;
- if ( regions[i].init_prot & VM_PROT_WRITE )
- protection |= PROT_WRITE;
- off_t offset = regions[i].file_offset;
- //fprintf(stderr, "mmap(%p, 0x%08lX, block=0x%08X, %s\n", mmapAddress, size, biggestDiff, fPath);
- mmapAddress = mmap(mmapAddress, size, protection, MAP_FILE | MAP_FIXED | MAP_PRIVATE, fd, offset);
- if ( mmapAddress == ((void*)(-1)) )
- throw "mmap error";
- }
- }
-
- return 0;
-}
-
static
bool
@@ -469,7 +437,6 @@
kSharedRegionLoadFileState,
kSharedRegionMapFileState,
kSharedRegionMapFilePrivateState,
- kSharedRegionMapFilePrivateMMapState,
kSharedRegionMapFilePrivateOutsideState,
};
static SharedRegionState sSharedRegionState = kSharedRegionStartState;
@@ -480,15 +447,7 @@
if ( kSharedRegionStartState == sSharedRegionState ) {
if ( hasSharedRegionMapFile() ) {
- if ( context.slideAndPackDylibs ) {
- sharedRegionMakePrivate(context);
- // remove underlying submap and block out 0x90000000 to 0xAFFFFFFF
- vm_address_t addr = (vm_address_t)0x90000000;
- vm_deallocate(mach_task_self(), addr, 0x20000000);
- vm_allocate(mach_task_self(), &addr, 0x20000000, false);
- sSharedRegionState = kSharedRegionMapFilePrivateMMapState;
- }
- else if ( context.sharedRegionMode == kUsePrivateSharedRegion ) {
+ if ( (context.sharedRegionMode == kUsePrivateSharedRegion) || context.slideAndPackDylibs ) {
sharedRegionMakePrivate(context);
sSharedRegionState = kSharedRegionMapFilePrivateState;
}
@@ -517,8 +476,8 @@
}
}
- if ( (kSharedRegionMapFilePrivateState == sSharedRegionState) || (kSharedRegionMapFilePrivateMMapState == sSharedRegionState) ) {
- if ( 0 != sharedRegionMapFilePrivate(fd, offsetInFat, lenInFat, fileLen, context, (kSharedRegionMapFilePrivateMMapState == sSharedRegionState)) ) {
+ if ( kSharedRegionMapFilePrivateState == sSharedRegionState ) {
+ if ( 0 != sharedRegionMapFilePrivate(fd, offsetInFat, lenInFat, fileLen, context) ) {
sSharedRegionState = kSharedRegionMapFilePrivateOutsideState;
}
}
@@ -649,14 +608,12 @@
return r;
}
-
int
ImageLoaderMachO::sharedRegionMapFilePrivate(int fd,
uint64_t offsetInFat,
uint64_t lenInFat,
uint64_t fileLen,
- const LinkContext& context,
- bool usemmap)
+ const LinkContext& context)
{
const unsigned int segmentCount = fSegments.size();
@@ -693,11 +650,7 @@
uint64_t slide = 0;
// try map it in privately (don't allow sliding if we pre-calculated the load address to pack dylibs)
- int r;
- if ( usemmap )
- r = _shared_region_map_file_with_mmap(fd, mappingTableCount, mappingTable);
- else
- r = _shared_region_map_file_np(fd, mappingTableCount, mappingTable, context.slideAndPackDylibs ? NULL : &slide);
+ int r = _shared_region_map_file_np(fd, mappingTableCount, mappingTable, context.slideAndPackDylibs ? NULL : &slide);
if ( 0 == r ) {
if ( 0 != slide ) {
slide = (slide) & (-4096); // round down to page boundary
@@ -749,7 +702,7 @@
}
}
if ( context.slideAndPackDylibs && (r != 0) )
- throwf("can't rebase split-seg dylib %s because shared_region_map_file_np() returned %d", this->getPath(), r);
+ throw "can't rebase split-seg dylib";
return r;
}
@@ -938,9 +891,8 @@
fModInitSection = sect;
else if ( type == S_MOD_TERM_FUNC_POINTERS )
fModTermSection = sect;
- else if ( isDataSeg && (strcmp(sect->sectname, "__dyld") == 0) ) {
- fDATAdyld = sect;
- }
+ else if ( isDataSeg && (strcmp(sect->sectname, "__dyld") == 0) )
+ fDATAdyld = sect;
else if ( isDataSeg && (strcmp(sect->sectname, "__image_notify") == 0) )
fImageNotifySection = sect;
}
@@ -954,12 +906,6 @@
fDylibID = (struct dylib_command*)cmd;
}
break;
- case LC_LOAD_WEAK_DYLIB:
- // do nothing, just prevent LC_REQ_DYLD exception from occuring
- break;
- default:
- if ( (cmd->cmd & LC_REQ_DYLD) != 0 )
- throwf("unknown required load command 0x%08X", cmd->cmd);
}
cmd = (const struct load_command*)(((char*)cmd)+cmd->cmdsize);
}
@@ -1259,7 +1205,7 @@
// cache this value that is used in the following loop
register const uintptr_t slide = this->fSlide;
-
+
// loop through all local (internal) relocation records
const uintptr_t relocBase = this->getRelocBase();
const relocation_info* const relocsStart = (struct relocation_info*)(&fLinkEditBase[fDynamicInfo->locreloff]);
@@ -1769,34 +1715,6 @@
}
}
-// returns if 'addr' is within the address range of section 'sectionIndex'
-// fSlide is not used. 'addr' is assumed to be a prebound address in this image
-bool ImageLoaderMachO::isAddrInSection(uintptr_t addr, uint8_t sectionIndex)
-{
- uint8_t currentSectionIndex = 1;
- 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 (unsigned long i = 0; i < cmd_count; ++i) {
- if ( cmd->cmd == LC_SEGMENT_COMMAND ) {
- const struct macho_segment_command* seg = (struct macho_segment_command*)cmd;
- if ( (currentSectionIndex <= sectionIndex) && (sectionIndex < currentSectionIndex+seg->nsects) ) {
- // 'sectionIndex' is in this segment, get section info
- const struct macho_section* const sectionsStart = (struct macho_section*)((char*)seg + sizeof(struct macho_segment_command));
- const struct macho_section* const section = §ionsStart[sectionIndex-currentSectionIndex];
- return ( (section->addr <= addr) && (addr < section->addr+section->size) );
- }
- else {
- // 'sectionIndex' not in this segment, skip to next segment
- currentSectionIndex += seg->nsects;
- }
- }
- cmd = (const struct load_command*)(((char*)cmd)+cmd->cmdsize);
- }
-
- return false;
-}
-
void ImageLoaderMachO::doBindExternalRelocations(const LinkContext& context, bool onlyCoalescedSymbols)
{
const uintptr_t relocBase = this->getRelocBase();
@@ -1826,31 +1744,12 @@
continue;
uintptr_t* location = ((uintptr_t*)(reloc->r_address + relocBase));
uintptr_t value = *location;
- #if __i386__
- if ( reloc->r_pcrel ) {
- value += (uintptr_t)location + 4 - fSlide;
- }
- #endif
if ( prebound ) {
// we are doing relocations, so prebinding was not usable
- // in a prebound executable, the n_value field of an undefined symbol is set to the address where the symbol was found when prebound
+ // in a prebound executable, the n_value field is set to the address where the symbol was found when prebound
// so, subtracting that gives the initial displacement which we need to add to the newly found symbol address
- // if mach-o relocation structs had an "addend" field this complication would not be necessary.
- if ( ((undefinedSymbol->n_type & N_TYPE) == N_SECT) && ((undefinedSymbol->n_desc & N_WEAK_DEF) != 0) ) {
- // weak symbols need special casing, since *location may have been prebound to a definition in another image.
- // If *location is currently prebound to somewhere in the same section as the weak definition, we assume
- // that we can subtract off the weak symbol address to get the addend.
- // If prebound elsewhere, we've lost the addend and have to assume it is zero.
- // The prebinding to elsewhere only happens with 10.4+ update_prebinding which only operates on a small set of Apple dylibs
- if ( (value == undefinedSymbol->n_value) || this->isAddrInSection(value, undefinedSymbol->n_sect) )
- value -= undefinedSymbol->n_value;
- else
- value = 0;
- }
- else {
- // is undefined or non-weak symbol, so do subtraction to get addend
- value -= undefinedSymbol->n_value;
- }
+ // if mach-o relocation structs had an "addend" field this would not be necessary.
+ value -= undefinedSymbol->n_value;
}
// if undefinedSymbol is same as last time, then symbolAddr and image will resolve to the same too
if ( undefinedSymbol != lastUndefinedSymbol ) {
@@ -1874,20 +1773,7 @@
}
}
value += symbolAddr;
- #if __i386__
- if ( reloc->r_pcrel ) {
- *location = value - ((uintptr_t)location + 4);
- }
- else {
- // don't dirty page if prebound value was correct
- if ( !prebound || (*location != value) )
- *location = value;
- }
- #else
- // don't dirty page if prebound value was correct
- if ( !prebound || (*location != value) )
- *location = value;
- #endif
+ *location = value;
}
break;
default:
@@ -2410,14 +2296,13 @@
// walk all exports and slide their n_value
struct macho_nlist* lastExport = &symbolTable[dysymtab->iextdefsym+dysymtab->nextdefsym];
for (struct macho_nlist* entry = &symbolTable[dysymtab->iextdefsym]; entry < lastExport; ++entry) {
- if ( (entry->n_type & N_TYPE) == N_SECT )
- entry->n_value += fSlide;
+ entry->n_value += fSlide;
}
// walk all local symbols and slide their n_value
struct macho_nlist* lastLocal = &symbolTable[dysymtab->ilocalsym+dysymtab->nlocalsym];
for (struct macho_nlist* entry = &symbolTable[dysymtab->ilocalsym]; entry < lastLocal; ++entry) {
- if ( entry->n_sect != NO_SECT )
+ if ( (entry->n_type & N_TYPE) == N_SECT )
entry->n_value += fSlide;
}
@@ -2442,67 +2327,8 @@
}
}
}
-
- // if multi-module, fix up objc_addr (10.4 and later runtime does not use this, but we want to keep file checksum consistent)
- if ( dysymtab->nmodtab != 0 ) {
- dylib_module* const modulesStart = (struct dylib_module*)(&fileToPrebind[dysymtab->modtaboff]);
- dylib_module* const modulesEnd = &modulesStart[dysymtab->nmodtab];
- for (dylib_module* module=modulesStart; module < modulesEnd; ++module) {
- if ( module->objc_module_info_size != 0 ) {
- module->objc_module_info_addr += fSlide;
- }
- }
- }
-}
-
-// file on disk has been reprebound, but we are still mapped to old file
-void ImageLoaderMachO::prebindUnmap(const LinkContext& context)
-{
- // this removes all mappings to the old file, so the kernel will unlink (delete) it.
- // We need to leave the load commands and __LINKEDIT in place
- for (std::vector<class Segment*>::iterator it=fSegments.begin(); it != fSegments.end(); ++it) {
- void* segmentAddress = (void*)((*it)->getActualLoadAddress());
- uintptr_t segmentSize = (*it)->getSize();
- //fprintf(stderr, "unmapping segment %s at %p for %s\n", (*it)->getName(), segmentAddress, this->getPath());
- // save load commands at beginning of __TEXT segment
- if ( segmentAddress == fMachOData ) {
- // typically load commands are one or two pages in size, so ok to alloc on stack
- uint32_t loadCmdSize = sizeof(macho_header) + ((macho_header*)fMachOData)->sizeofcmds;
- uint32_t loadCmdPages = (loadCmdSize+4095) & (-4096);
- uint8_t loadcommands[loadCmdPages];
- memcpy(loadcommands, fMachOData, loadCmdPages);
- // unmap whole __TEXT segment
- munmap((void*)(fMachOData), segmentSize);
- // allocate and copy back mach_header and load commands
- vm_address_t addr = (vm_address_t)fMachOData;
- int r2 = vm_allocate(mach_task_self(), &addr, loadCmdPages, false /*at this address*/);
- if ( r2 != 0 )
- fprintf(stderr, "prebindUnmap() vm_allocate for __TEXT %d failed\n", loadCmdPages);
- memcpy((void*)fMachOData, loadcommands, loadCmdPages);
- //fprintf(stderr, "copying back load commands to %p size=%u for %s\n", segmentAddress, loadCmdPages, this->getPath());
- }
- else if ( strcmp((*it)->getName(), "__LINKEDIT") == 0 ) {
- uint32_t linkEditSize = segmentSize;
- uint32_t linkEditPages = (linkEditSize+4095) & (-4096);
- void* linkEditTmp = malloc(linkEditPages);
- memcpy(linkEditTmp, segmentAddress, linkEditPages);
- // unmap whole __LINKEDIT segment
- munmap(segmentAddress, segmentSize);
- vm_address_t addr = (vm_address_t)segmentAddress;
- int r2 = vm_allocate(mach_task_self(), &addr, linkEditPages, false /*at this address*/);
- if ( r2 != 0 )
- fprintf(stderr, "prebindUnmap() vm_allocate for __LINKEDIT %d failed\n", linkEditPages);
- memcpy(segmentAddress, linkEditTmp, linkEditPages);
- //fprintf(stderr, "copying back __LINKEDIT to %p size=%u for %s\n", segmentAddress, linkEditPages, this->getPath());
- free(linkEditTmp);
- }
- else {
- // unmap any other segment
- munmap((void*)(segmentAddress), (*it)->getSize());
- }
- }
-}
-
+
+}
SegmentMachO::SegmentMachO(const struct macho_segment_command* cmd, ImageLoaderMachO* image, const uint8_t* fileData)