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--- dyld/dyld-132.13/src/ImageLoaderMachO.cpp
+++ dyld/dyld-360.22/src/ImageLoaderMachO.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@
*
@@ -27,7 +27,7 @@
#define __eip eip
#define __rip rip
-
+#define __STDC_LIMIT_MACROS
#include <string.h>
#include <fcntl.h>
#include <errno.h>
@@ -40,26 +40,47 @@
#include <mach-o/loader.h>
#include <mach-o/nlist.h>
#include <sys/sysctl.h>
+#include <sys/syscall.h>
#include <libkern/OSAtomic.h>
#include <libkern/OSCacheControl.h>
+#include <stdint.h>
+#include <System/sys/codesign.h>
#include "ImageLoaderMachO.h"
#include "ImageLoaderMachOCompressed.h"
+#if SUPPORT_CLASSIC_MACHO
#include "ImageLoaderMachOClassic.h"
+#endif
#include "mach-o/dyld_images.h"
+// <rdar://problem/8718137> use stack guard random value to add padding between dylibs
+extern "C" long __stack_chk_guard;
+
+#ifndef LC_LOAD_UPWARD_DYLIB
+ #define LC_LOAD_UPWARD_DYLIB (0x23|LC_REQ_DYLD) /* load of dylib whose initializers run later */
+#endif
+
+#ifndef LC_VERSION_MIN_TVOS
+ #define LC_VERSION_MIN_TVOS 0x2F
+#endif
+
+#ifndef LC_VERSION_MIN_WATCHOS
+ #define LC_VERSION_MIN_WATCHOS 0x30
+#endif
// relocation_info.r_length field has value 3 for 64-bit executables and value 2 for 32-bit executables
#if __LP64__
#define LC_SEGMENT_COMMAND LC_SEGMENT_64
#define LC_ROUTINES_COMMAND LC_ROUTINES_64
+ #define LC_SEGMENT_COMMAND_WRONG LC_SEGMENT
struct macho_segment_command : public segment_command_64 {};
struct macho_section : public section_64 {};
struct macho_routines_command : public routines_command_64 {};
#else
#define LC_SEGMENT_COMMAND LC_SEGMENT
#define LC_ROUTINES_COMMAND LC_ROUTINES
+ #define LC_SEGMENT_COMMAND_WRONG LC_SEGMENT_64
struct macho_segment_command : public segment_command {};
struct macho_section : public section {};
struct macho_routines_command : public routines_command {};
@@ -71,9 +92,9 @@
ImageLoaderMachO::ImageLoaderMachO(const macho_header* mh, const char* path, unsigned int segCount,
uint32_t segOffsets[], unsigned int libCount)
- : ImageLoader(path, libCount), fMachOData((uint8_t*)mh), fLinkEditBase(NULL), fSlide(0),
+ : ImageLoader(path, libCount), fCoveredCodeLength(0), fMachOData((uint8_t*)mh), fLinkEditBase(NULL), fSlide(0),
fEHFrameSectionOffset(0), fUnwindInfoSectionOffset(0), fDylibIDOffset(0),
- fSegmentsCount(segCount), fIsSplitSeg(false), fInSharedCache(false),
+fSegmentsCount(segCount), fIsSplitSeg(false), fInSharedCache(false),
#if TEXT_RELOC_SUPPORT
fTextSegmentRebases(false),
fTextSegmentBinds(false),
@@ -82,7 +103,7 @@
fReadOnlyImportSegment(false),
#endif
fHasSubLibraries(false), fHasSubUmbrella(false), fInUmbrella(false), fHasDOFSections(false), fHasDashInit(false),
- fHasInitializers(false), fHasTerminators(false)
+ fHasInitializers(false), fHasTerminators(false), fRegisteredAsRequiresCoalescing(false)
{
fIsSplitSeg = ((mh->flags & MH_SPLIT_SEGS) != 0);
@@ -97,7 +118,7 @@
// ignore zero-sized segments
if ( segCmd->vmsize != 0 ) {
// record offset of load command
- segOffsets[segIndex++] = (uint8_t*)segCmd - fMachOData;
+ segOffsets[segIndex++] = (uint32_t)((uint8_t*)segCmd - fMachOData);
}
}
cmd = (const struct load_command*)(((char*)cmd)+cmd->cmdsize);
@@ -107,44 +128,167 @@
// determine if this mach-o file has classic or compressed LINKEDIT and number of segments it has
-void ImageLoaderMachO::sniffLoadCommands(const macho_header* mh, const char* path, bool* compressed,
- unsigned int* segCount, unsigned int* libCount)
+void ImageLoaderMachO::sniffLoadCommands(const macho_header* mh, const char* path, bool inCache, bool* compressed,
+ unsigned int* segCount, unsigned int* libCount, const LinkContext& context,
+ const linkedit_data_command** codeSigCmd,
+ const encryption_info_command** encryptCmd)
{
*compressed = false;
*segCount = 0;
*libCount = 0;
+ *codeSigCmd = NULL;
+ *encryptCmd = NULL;
+
const uint32_t cmd_count = mh->ncmds;
- const struct load_command* const cmds = (struct load_command*)(((uint8_t*)mh) + sizeof(macho_header));
+ const struct load_command* const startCmds = (struct load_command*)(((uint8_t*)mh) + sizeof(macho_header));
const struct load_command* const endCmds = (struct load_command*)(((uint8_t*)mh) + sizeof(macho_header) + mh->sizeofcmds);
- const struct load_command* cmd = cmds;
+ const struct load_command* cmd = startCmds;
+ bool foundLoadCommandSegment = false;
for (uint32_t i = 0; i < cmd_count; ++i) {
+ uint32_t cmdLength = cmd->cmdsize;
+ struct macho_segment_command* segCmd;
+ if ( cmdLength < 8 ) {
+ dyld::throwf("malformed mach-o image: load command #%d length (%u) too small in %s",
+ i, cmdLength, path);
+ }
+ const struct load_command* const nextCmd = (const struct load_command*)(((char*)cmd)+cmdLength);
+ if ( (nextCmd > endCmds) || (nextCmd < cmd) ) {
+ dyld::throwf("malformed mach-o image: load command #%d length (%u) would exceed sizeofcmds (%u) in %s",
+ i, cmdLength, mh->sizeofcmds, path);
+ }
switch (cmd->cmd) {
case LC_DYLD_INFO:
case LC_DYLD_INFO_ONLY:
*compressed = true;
break;
case LC_SEGMENT_COMMAND:
+ segCmd = (struct macho_segment_command*)cmd;
+#if __MAC_OS_X_VERSION_MIN_REQUIRED
+ // rdar://problem/19617624 allow unmapped segments on OSX (but not iOS)
+ if ( (segCmd->filesize > segCmd->vmsize) && (segCmd->vmsize != 0) )
+#else
+ if ( segCmd->filesize > segCmd->vmsize )
+#endif
+ dyld::throwf("malformed mach-o image: segment load command %s filesize is larger than vmsize", segCmd->segname);
// ignore zero-sized segments
- if ( ((struct macho_segment_command*)cmd)->vmsize != 0 )
+ if ( segCmd->vmsize != 0 )
*segCount += 1;
+ if ( context.codeSigningEnforced ) {
+ uintptr_t vmStart = segCmd->vmaddr;
+ uintptr_t vmSize = segCmd->vmsize;
+ uintptr_t vmEnd = vmStart + vmSize;
+ uintptr_t fileStart = segCmd->fileoff;
+ uintptr_t fileSize = segCmd->filesize;
+ if ( (intptr_t)(vmEnd) < 0)
+ dyld::throwf("malformed mach-o image: segment load command %s vmsize too large", segCmd->segname);
+ if ( vmStart > vmEnd )
+ dyld::throwf("malformed mach-o image: segment load command %s wraps around address space", segCmd->segname);
+ if ( vmSize != fileSize ) {
+ if ( (segCmd->initprot == 0) && (fileSize != 0) )
+ dyld::throwf("malformed mach-o image: unaccessable segment %s has filesize != 0", segCmd->segname);
+ else if ( vmSize < fileSize )
+ dyld::throwf("malformed mach-o image: segment %s has vmsize < filesize", segCmd->segname);
+ }
+ if ( inCache ) {
+ if ( (fileSize != 0) && (segCmd->initprot == (VM_PROT_READ | VM_PROT_EXECUTE)) ) {
+ if ( foundLoadCommandSegment )
+ throw "load commands in multiple segments";
+ foundLoadCommandSegment = true;
+ }
+ }
+ else if ( (fileStart < mh->sizeofcmds) && (fileSize != 0) ) {
+ // <rdar://problem/7942521> all load commands must be in an executable segment
+ if ( (fileStart != 0) || (fileSize < (mh->sizeofcmds+sizeof(macho_header))) )
+ dyld::throwf("malformed mach-o image: segment %s does not span all load commands", segCmd->segname);
+ if ( segCmd->initprot != (VM_PROT_READ | VM_PROT_EXECUTE) )
+ dyld::throwf("malformed mach-o image: load commands found in segment %s with wrong permissions", segCmd->segname);
+ if ( foundLoadCommandSegment )
+ throw "load commands in multiple segments";
+ foundLoadCommandSegment = true;
+ }
+
+ const struct macho_section* const sectionsStart = (struct macho_section*)((char*)segCmd + sizeof(struct macho_segment_command));
+ const struct macho_section* const sectionsEnd = §ionsStart[segCmd->nsects];
+ for (const struct macho_section* sect=sectionsStart; sect < sectionsEnd; ++sect) {
+ if (!inCache && sect->offset != 0 && ((sect->offset + sect->size) > (segCmd->fileoff + segCmd->filesize)))
+ dyld::throwf("malformed mach-o image: section %s,%s of '%s' exceeds segment %s booundary", sect->segname, sect->sectname, path, segCmd->segname);
+ }
+ }
+ break;
+ case LC_SEGMENT_COMMAND_WRONG:
+ dyld::throwf("malformed mach-o image: wrong LC_SEGMENT[_64] for architecture");
break;
case LC_LOAD_DYLIB:
case LC_LOAD_WEAK_DYLIB:
case LC_REEXPORT_DYLIB:
+ case LC_LOAD_UPWARD_DYLIB:
*libCount += 1;
break;
- }
- uint32_t cmdLength = cmd->cmdsize;
- cmd = (const struct load_command*)(((char*)cmd)+cmdLength);
- if ( cmd > endCmds ) {
- dyld::throwf("malformed mach-o image: load command #%d length (%u) would exceed sizeofcmds (%u) in %s",
- i, cmdLength, mh->sizeofcmds, path);
- }
- }
+ case LC_CODE_SIGNATURE:
+ *codeSigCmd = (struct linkedit_data_command*)cmd; // only support one LC_CODE_SIGNATURE per image
+ break;
+ case LC_ENCRYPTION_INFO:
+ case LC_ENCRYPTION_INFO_64:
+ *encryptCmd = (struct encryption_info_command*)cmd; // only support one LC_ENCRYPTION_INFO[_64] per image
+ break;
+ }
+ cmd = nextCmd;
+ }
+
+ if ( context.codeSigningEnforced && !foundLoadCommandSegment )
+ throw "load commands not in a segment";
+
+ // <rdar://problem/13145644> verify every segment does not overlap another segment
+ if ( context.codeSigningEnforced ) {
+ uintptr_t lastFileStart = 0;
+ uintptr_t linkeditFileStart = 0;
+ const struct load_command* cmd1 = startCmds;
+ for (uint32_t i = 0; i < cmd_count; ++i) {
+ if ( cmd1->cmd == LC_SEGMENT_COMMAND ) {
+ struct macho_segment_command* segCmd1 = (struct macho_segment_command*)cmd1;
+ uintptr_t vmStart1 = segCmd1->vmaddr;
+ uintptr_t vmEnd1 = segCmd1->vmaddr + segCmd1->vmsize;
+ uintptr_t fileStart1 = segCmd1->fileoff;
+ uintptr_t fileEnd1 = segCmd1->fileoff + segCmd1->filesize;
+
+ if (fileStart1 > lastFileStart)
+ lastFileStart = fileStart1;
+
+ if ( strcmp(&segCmd1->segname[0], "__LINKEDIT") == 0 ) {
+ linkeditFileStart = fileStart1;
+ }
+
+ const struct load_command* cmd2 = startCmds;
+ for (uint32_t j = 0; j < cmd_count; ++j) {
+ if ( cmd2 == cmd1 )
+ continue;
+ if ( cmd2->cmd == LC_SEGMENT_COMMAND ) {
+ struct macho_segment_command* segCmd2 = (struct macho_segment_command*)cmd2;
+ uintptr_t vmStart2 = segCmd2->vmaddr;
+ uintptr_t vmEnd2 = segCmd2->vmaddr + segCmd2->vmsize;
+ uintptr_t fileStart2 = segCmd2->fileoff;
+ uintptr_t fileEnd2 = segCmd2->fileoff + segCmd2->filesize;
+ if ( ((vmStart2 <= vmStart1) && (vmEnd2 > vmStart1) && (vmEnd1 > vmStart1))
+ || ((vmStart2 >= vmStart1) && (vmStart2 < vmEnd1) && (vmEnd2 > vmStart2)) )
+ dyld::throwf("malformed mach-o image: segment %s vm overlaps segment %s", segCmd1->segname, segCmd2->segname);
+ if ( ((fileStart2 <= fileStart1) && (fileEnd2 > fileStart1) && (fileEnd1 > fileStart1))
+ || ((fileStart2 >= fileStart1) && (fileStart2 < fileEnd1) && (fileEnd2 > fileStart2)) )
+ dyld::throwf("malformed mach-o image: segment %s file content overlaps segment %s", segCmd1->segname, segCmd2->segname);
+ }
+ cmd2 = (const struct load_command*)(((char*)cmd2)+cmd2->cmdsize);
+ }
+ }
+ cmd1 = (const struct load_command*)(((char*)cmd1)+cmd1->cmdsize);
+ }
+
+ if (lastFileStart != linkeditFileStart)
+ dyld::throwf("malformed mach-o image: __LINKEDIT must be last segment");
+ }
+
// fSegmentsArrayCount is only 8-bits
if ( *segCount > 255 )
dyld::throwf("malformed mach-o image: more than 255 segments in %s", path);
-
+
// fSegmentsArrayCount is only 8-bits
if ( *libCount > 4095 )
dyld::throwf("malformed mach-o image: more than 4095 dependent libraries in %s", path);
@@ -163,12 +307,18 @@
bool compressed;
unsigned int segCount;
unsigned int libCount;
- sniffLoadCommands(mh, path, &compressed, &segCount, &libCount);
+ const linkedit_data_command* codeSigCmd;
+ const encryption_info_command* encryptCmd;
+ sniffLoadCommands(mh, path, false, &compressed, &segCount, &libCount, context, &codeSigCmd, &encryptCmd);
// instantiate concrete class based on content of load commands
if ( compressed )
return ImageLoaderMachOCompressed::instantiateMainExecutable(mh, slide, path, segCount, libCount, context);
else
+#if SUPPORT_CLASSIC_MACHO
return ImageLoaderMachOClassic::instantiateMainExecutable(mh, slide, path, segCount, libCount, context);
+#else
+ throw "missing LC_DYLD_INFO load command";
+#endif
}
@@ -190,27 +340,39 @@
bool compressed;
unsigned int segCount;
unsigned int libCount;
- sniffLoadCommands((const macho_header*)fileData, path, &compressed, &segCount, &libCount);
+ const linkedit_data_command* codeSigCmd;
+ const encryption_info_command* encryptCmd;
+ sniffLoadCommands((const macho_header*)fileData, path, false, &compressed, &segCount, &libCount, context, &codeSigCmd, &encryptCmd);
// instantiate concrete class based on content of load commands
if ( compressed )
- return ImageLoaderMachOCompressed::instantiateFromFile(path, fd, fileData, offsetInFat, lenInFat, info, segCount, libCount, context);
+ return ImageLoaderMachOCompressed::instantiateFromFile(path, fd, fileData, dataSize, offsetInFat, lenInFat, info, segCount, libCount, codeSigCmd, encryptCmd, context);
else
- return ImageLoaderMachOClassic::instantiateFromFile(path, fd, fileData, offsetInFat, lenInFat, info, segCount, libCount, context);
+#if SUPPORT_CLASSIC_MACHO
+ return ImageLoaderMachOClassic::instantiateFromFile(path, fd, fileData, dataSize, offsetInFat, lenInFat, info, segCount, libCount, codeSigCmd, context);
+#else
+ throw "missing LC_DYLD_INFO load command";
+#endif
}
// create image by using cached mach-o file
-ImageLoader* ImageLoaderMachO::instantiateFromCache(const macho_header* mh, const char* path, const struct stat& info, const LinkContext& context)
+ImageLoader* ImageLoaderMachO::instantiateFromCache(const macho_header* mh, const char* path, long slide, const struct stat& info, const LinkContext& context)
{
// instantiate right concrete class
bool compressed;
unsigned int segCount;
unsigned int libCount;
- sniffLoadCommands(mh, path, &compressed, &segCount, &libCount);
+ const linkedit_data_command* codeSigCmd;
+ const encryption_info_command* encryptCmd;
+ sniffLoadCommands(mh, path, true, &compressed, &segCount, &libCount, context, &codeSigCmd, &encryptCmd);
// instantiate concrete class based on content of load commands
if ( compressed )
- return ImageLoaderMachOCompressed::instantiateFromCache(mh, path, info, segCount, libCount, context);
+ return ImageLoaderMachOCompressed::instantiateFromCache(mh, path, slide, info, segCount, libCount, context);
else
- return ImageLoaderMachOClassic::instantiateFromCache(mh, path, info, segCount, libCount, context);
+#if SUPPORT_CLASSIC_MACHO
+ return ImageLoaderMachOClassic::instantiateFromCache(mh, path, slide, info, segCount, libCount, context);
+#else
+ throw "missing LC_DYLD_INFO load command";
+#endif
}
// create image by copying an in-memory mach-o file
@@ -219,27 +381,51 @@
bool compressed;
unsigned int segCount;
unsigned int libCount;
- sniffLoadCommands(mh, moduleName, &compressed, &segCount, &libCount);
+ const linkedit_data_command* sigcmd;
+ const encryption_info_command* encryptCmd;
+ sniffLoadCommands(mh, moduleName, false, &compressed, &segCount, &libCount, context, &sigcmd, &encryptCmd);
// instantiate concrete class based on content of load commands
if ( compressed )
return ImageLoaderMachOCompressed::instantiateFromMemory(moduleName, mh, len, segCount, libCount, context);
else
+#if SUPPORT_CLASSIC_MACHO
return ImageLoaderMachOClassic::instantiateFromMemory(moduleName, mh, len, segCount, libCount, context);
-}
-
-
-
-void ImageLoaderMachO::parseLoadCmds()
+#else
+ throw "missing LC_DYLD_INFO load command";
+#endif
+}
+
+
+int ImageLoaderMachO::crashIfInvalidCodeSignature()
+{
+ // Now that segments are mapped in, try reading from first executable segment.
+ // If code signing is enabled the kernel will validate the code signature
+ // when paging in, and kill the process if invalid.
+ for(unsigned int i=0; i < fSegmentsCount; ++i) {
+ if ( (segFileOffset(i) == 0) && (segFileSize(i) != 0) ) {
+ // return read value to ensure compiler does not optimize away load
+ int* p = (int*)segActualLoadAddress(i);
+ return *p;
+ }
+ }
+ return 0;
+}
+
+
+void ImageLoaderMachO::parseLoadCmds(const LinkContext& context)
{
// now that segments are mapped in, get real fMachOData, fLinkEditBase, and fSlide
for(unsigned int i=0; i < fSegmentsCount; ++i) {
// set up pointer to __LINKEDIT segment
- if ( strcmp(segName(i),"__LINKEDIT") == 0 )
+ if ( strcmp(segName(i),"__LINKEDIT") == 0 ) {
+ if ( context.codeSigningEnforced && (segFileOffset(i) > fCoveredCodeLength))
+ dyld::throwf("cannot load '%s' (segment outside of code signature)", this->getShortName());
fLinkEditBase = (uint8_t*)(segActualLoadAddress(i) - segFileOffset(i));
+ }
#if TEXT_RELOC_SUPPORT
// __TEXT segment always starts at beginning of file and contains mach_header and load commands
- if ( strcmp(segName(i),"__TEXT") == 0 ) {
- if ( segHasRebaseFixUps(i) )
+ if ( segExecutable(i) ) {
+ if ( segHasRebaseFixUps(i) && (fSlide != 0) )
fTextSegmentRebases = true;
if ( segHasBindFixUps(i) )
fTextSegmentBinds = true;
@@ -258,6 +444,7 @@
// keep count of prebound images with weak exports
if ( this->participatesInCoalescing() ) {
++fgImagesRequiringCoalescing;
+ fRegisteredAsRequiresCoalescing = true;
if ( this->hasCoalescedExports() )
++fgImagesHasWeakDefinitions;
}
@@ -270,6 +457,8 @@
const dyld_info_command* dyldInfo = NULL;
const macho_nlist* symbolTable = NULL;
const char* symbolTableStrings = NULL;
+ const struct load_command* firstUnknownCmd = NULL;
+ const struct version_min_command* minOSVersionCmd = NULL;
const dysymtab_command* dynSymbolTable = NULL;
const uint32_t cmd_count = ((macho_header*)fMachOData)->ncmds;
const struct load_command* const cmds = (struct load_command*)&fMachOData[sizeof(macho_header)];
@@ -317,9 +506,9 @@
else if ( type == S_DTRACE_DOF )
fHasDOFSections = true;
else if ( isTextSeg && (strcmp(sect->sectname, "__eh_frame") == 0) )
- fEHFrameSectionOffset = (uint8_t*)sect - fMachOData;
+ fEHFrameSectionOffset = (uint32_t)((uint8_t*)sect - fMachOData);
else if ( isTextSeg && (strcmp(sect->sectname, "__unwind_info") == 0) )
- fUnwindInfoSectionOffset = (uint8_t*)sect - fMachOData;;
+ fUnwindInfoSectionOffset = (uint32_t)((uint8_t*)sect - fMachOData);
}
}
break;
@@ -328,20 +517,43 @@
break;
case LC_ID_DYLIB:
{
- fDylibIDOffset = (uint8_t*)cmd - fMachOData;
+ fDylibIDOffset = (uint32_t)((uint8_t*)cmd - fMachOData);
}
break;
case LC_RPATH:
case LC_LOAD_WEAK_DYLIB:
case LC_REEXPORT_DYLIB:
+ case LC_LOAD_UPWARD_DYLIB:
+ case LC_MAIN:
// do nothing, just prevent LC_REQ_DYLD exception from occuring
break;
+ case LC_VERSION_MIN_MACOSX:
+ case LC_VERSION_MIN_IPHONEOS:
+ case LC_VERSION_MIN_TVOS:
+ case LC_VERSION_MIN_WATCHOS:
+ minOSVersionCmd = (version_min_command*)cmd;
+ break;
default:
- if ( (cmd->cmd & LC_REQ_DYLD) != 0 )
- dyld::throwf("unknown required load command 0x%08X", cmd->cmd);
+ if ( (cmd->cmd & LC_REQ_DYLD) != 0 ) {
+ if ( firstUnknownCmd == NULL )
+ firstUnknownCmd = cmd;
+ }
+ break;
}
cmd = (const struct load_command*)(((char*)cmd)+cmd->cmdsize);
}
+ if ( firstUnknownCmd != NULL ) {
+ if ( minOSVersionCmd != NULL ) {
+ dyld::throwf("cannot load '%s' because it was built for OS version %u.%u (load command 0x%08X is unknown)",
+ this->getShortName(),
+ minOSVersionCmd->version >> 16, ((minOSVersionCmd->version >> 8) & 0xff),
+ firstUnknownCmd->cmd);
+ }
+ else {
+ dyld::throwf("cannot load '%s' (load command 0x%08X is unknown)", this->getShortName(), firstUnknownCmd->cmd);
+ }
+ }
+
if ( dyldInfo != NULL )
this->setDyldInfo(dyldInfo);
@@ -354,8 +566,8 @@
// for UnmapSegments() to work
void ImageLoaderMachO::destroy()
{
- // keep count of images with weak exports
- if ( this->participatesInCoalescing() ) {
+ // update count of images with weak exports
+ if ( fRegisteredAsRequiresCoalescing ) {
--fgImagesRequiringCoalescing;
if ( this->hasCoalescedExports() )
--fgImagesHasWeakDefinitions;
@@ -459,6 +671,7 @@
bool ImageLoaderMachO::segHasRebaseFixUps(unsigned int segIndex) const
{
+#if TEXT_RELOC_SUPPORT
// scan sections for fix-up bit
const macho_segment_command* segCmd = segLoadCommand(segIndex);
const struct macho_section* const sectionsStart = (struct macho_section*)((char*)segCmd + sizeof(struct macho_segment_command));
@@ -467,11 +680,13 @@
if ( (sect->flags & S_ATTR_LOC_RELOC) != 0 )
return true;
}
+#endif
return false;
}
bool ImageLoaderMachO::segHasBindFixUps(unsigned int segIndex) const
{
+#if TEXT_RELOC_SUPPORT
// scan sections for fix-up bit
const macho_segment_command* segCmd = segLoadCommand(segIndex);
const struct macho_section* const sectionsStart = (struct macho_section*)((char*)segCmd + sizeof(struct macho_segment_command));
@@ -480,6 +695,7 @@
if ( (sect->flags & S_ATTR_EXT_RELOC) != 0 )
return true;
}
+#endif
return false;
}
@@ -529,7 +745,7 @@
// prefetch writable segment that have mmap'ed regions
radvisory advice;
advice.ra_offset = offsetInFat + segFileOffset(i);
- advice.ra_count = segFileSize(i);
+ advice.ra_count = (int)segFileSize(i);
// limit prefetch to 1MB (256 pages)
if ( advice.ra_count > 1024*1024 )
advice.ra_count = 1024*1024;
@@ -628,39 +844,98 @@
fSlide = slide;
}
-#if CODESIGNING_SUPPORT
-void ImageLoaderMachO::loadCodeSignature(const uint8_t* fileData, int fd, uint64_t offsetInFatFile)
-{
- // look for code signature load command
- // do this in the read() memory buffer - not in the mapped __TEXT segment
- const uint32_t cmd_count = ((macho_header*)fileData)->ncmds;
- const struct load_command* const cmds = (struct load_command*)&fileData[sizeof(macho_header)];
- const struct load_command* cmd = cmds;
- for (uint32_t i = 0; i < cmd_count; ++i) {
- if ( cmd->cmd == LC_CODE_SIGNATURE ) {
- const struct linkedit_data_command *sigcmd = (struct linkedit_data_command*) cmd;
- // fLinkEditBase is not set up yet, so compute it
- const uint8_t* linkEditBase = NULL;
- for(unsigned int i=0; i < fSegmentsCount; ++i) {
- // set up pointer to __LINKEDIT segment
- if ( strcmp(segName(i),"__LINKEDIT") == 0 ) {
- linkEditBase = (uint8_t*)(segActualLoadAddress(i) - segFileOffset(i));
- break;
+void ImageLoaderMachO::loadCodeSignature(const struct linkedit_data_command* codeSigCmd, int fd, uint64_t offsetInFatFile, const LinkContext& context)
+{
+ // if dylib being loaded has no code signature load command
+ if ( codeSigCmd == NULL ) {
+#if __MAC_OS_X_VERSION_MIN_REQUIRED
+ bool codeSigningEnforced = context.codeSigningEnforced;
+ if ( context.mainExecutableCodeSigned && !codeSigningEnforced ) {
+ static bool codeSignEnforcementDynamicallyEnabled = false;
+ if ( !codeSignEnforcementDynamicallyEnabled ) {
+ uint32_t flags;
+ if ( csops(0, CS_OPS_STATUS, &flags, sizeof(flags)) != -1 ) {
+ if ( flags & CS_ENFORCEMENT ) {
+ codeSignEnforcementDynamicallyEnabled = true;
+ }
}
}
- fsignatures_t siginfo;
- siginfo.fs_file_start=offsetInFatFile; // CD coverage offset
- siginfo.fs_blob_start=(void*)(linkEditBase+sigcmd->dataoff); // start of CD in file
- siginfo.fs_blob_size=sigcmd->datasize; // size of CD
- int result = fcntl(fd, F_ADDSIGS, &siginfo);
- if ( result == -1 )
- dyld::log("dyld: code signature failed for %s with errno=%d\n", this->getPath(), errno);
- break; // only support one LC_CODE_SIGNATURE
- }
- cmd = (const struct load_command*)(((char*)cmd)+cmd->cmdsize);
- }
-}
-#endif
+ codeSigningEnforced = codeSignEnforcementDynamicallyEnabled;
+ }
+ // if we require dylibs to be code signed
+ if ( codeSigningEnforced ) {
+ // if there is a non-load command based code signature, use it
+ off_t offset = (off_t)offsetInFatFile;
+ if ( fcntl(fd, F_FINDSIGS, &offset, sizeof(offset)) != -1 )
+ return;
+ // otherwise gracefully return from dlopen()
+ dyld::throwf("required code signature missing for '%s'\n", this->getPath());
+ }
+#endif
+ //Since we don't have a range for the signature we have to assume full coverage
+ fCoveredCodeLength = UINT64_MAX;
+ }
+ else {
+#if __MAC_OS_X_VERSION_MIN_REQUIRED
+ // <rdar://problem/13622786> ignore code signatures in binaries built with pre-10.9 tools
+ if ( this->sdkVersion() < DYLD_MACOSX_VERSION_10_9 ) {
+ return;
+ }
+#endif
+ fsignatures_t siginfo;
+ siginfo.fs_file_start=offsetInFatFile; // start of mach-o slice in fat file
+ siginfo.fs_blob_start=(void*)(long)(codeSigCmd->dataoff); // start of CD in mach-o file
+ siginfo.fs_blob_size=codeSigCmd->datasize; // size of CD
+ int result = fcntl(fd, F_ADDFILESIGS_RETURN, &siginfo);
+
+#if TARGET_IPHONE_SIMULATOR
+ // rdar://problem/18759224> check range covered by the code directory after loading
+ // Attempt to fallback only if we are in the simulator
+
+ if ( result == -1 ) {
+ result = fcntl(fd, F_ADDFILESIGS, &siginfo);
+ siginfo.fs_file_start = codeSigCmd->dataoff;
+ }
+#endif
+
+ if ( result == -1 ) {
+ if ( (errno == EPERM) || (errno == EBADEXEC) )
+ dyld::throwf("code signature invalid for '%s'\n", this->getPath());
+ if ( context.verboseCodeSignatures )
+ dyld::log("dyld: Failed registering code signature for %s, errno=%d\n", this->getPath(), errno);
+ siginfo.fs_file_start = UINT64_MAX;
+ } else if ( context.verboseCodeSignatures ) {
+ dyld::log("dyld: Registered code signature for %s\n", this->getPath());
+ }
+ fCoveredCodeLength = siginfo.fs_file_start;
+ }
+}
+
+void ImageLoaderMachO::validateFirstPages(const struct linkedit_data_command* codeSigCmd, int fd, const uint8_t *fileData, size_t lenFileData, off_t offsetInFat, const LinkContext& context)
+{
+#if __MAC_OS_X_VERSION_MIN_REQUIRED
+ // rdar://problem/21839703> 15A226d: dyld crashes in mageLoaderMachO::validateFirstPages during dlopen() after encountering an mmap failure
+ // We need to ignore older code signatures because they will be bad.
+ if ( this->sdkVersion() < DYLD_MACOSX_VERSION_10_9 ) {
+ return;
+ }
+#endif
+ if (codeSigCmd != NULL) {
+ if ( context.verboseMapping )
+ dyld::log("dyld: validate pages: %llu\n", (unsigned long long)offsetInFat);
+
+ void *fdata = xmmap(NULL, lenFileData, PROT_READ | PROT_EXEC, MAP_SHARED, fd, offsetInFat);
+ if ( fdata == MAP_FAILED ) {
+ if ( context.processRequiresLibraryValidation )
+ dyld::throwf("cannot load image with wrong team ID in process using Library Validation");
+ else
+ dyld::throwf("mmap() errno=%d validating first page of '%s'", errno, getInstallPath());
+ }
+ if ( memcmp(fdata, fileData, lenFileData) != 0 )
+ dyld::throwf("mmap() page compare failed for '%s'", getInstallPath());
+ munmap(fdata, lenFileData);
+ }
+}
const char* ImageLoaderMachO::getInstallPath() const
@@ -672,6 +947,115 @@
return NULL;
}
+void ImageLoaderMachO::registerInterposing()
+{
+ // mach-o files advertise interposing by having a __DATA __interpose section
+ struct InterposeData { uintptr_t replacement; uintptr_t replacee; };
+ 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) {
+ if ( ((sect->flags & SECTION_TYPE) == S_INTERPOSING) || ((strcmp(sect->sectname, "__interpose") == 0) && (strcmp(seg->segname, "__DATA") == 0)) ) {
+ const InterposeData* interposeArray = (InterposeData*)(sect->addr + fSlide);
+ const size_t count = sect->size / sizeof(InterposeData);
+ for (size_t i=0; i < count; ++i) {
+ ImageLoader::InterposeTuple tuple;
+ tuple.replacement = interposeArray[i].replacement;
+ tuple.neverImage = this;
+ tuple.onlyImage = NULL;
+ tuple.replacee = interposeArray[i].replacee;
+ // <rdar://problem/7937695> verify that replacement is in this image
+ if ( this->containsAddress((void*)tuple.replacement) ) {
+ // chain to any existing interpositions
+ for (std::vector<InterposeTuple>::iterator it=fgInterposingTuples.begin(); it != fgInterposingTuples.end(); it++) {
+ if ( it->replacee == tuple.replacee ) {
+ tuple.replacee = it->replacement;
+ }
+ }
+ ImageLoader::fgInterposingTuples.push_back(tuple);
+ }
+ }
+ }
+ }
+ }
+ break;
+ }
+ cmd = (const struct load_command*)(((char*)cmd)+cmd->cmdsize);
+ }
+}
+
+uint32_t ImageLoaderMachO::sdkVersion() const
+{
+ 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;
+ const struct version_min_command* versCmd;
+ for (uint32_t i = 0; i < cmd_count; ++i) {
+ switch ( cmd->cmd ) {
+ case LC_VERSION_MIN_MACOSX:
+ case LC_VERSION_MIN_IPHONEOS:
+ case LC_VERSION_MIN_TVOS:
+ case LC_VERSION_MIN_WATCHOS:
+ versCmd = (version_min_command*)cmd;
+ return versCmd->sdk;
+ }
+ cmd = (const struct load_command*)(((char*)cmd)+cmd->cmdsize);
+ }
+ return 0;
+}
+
+uint32_t ImageLoaderMachO::minOSVersion(const mach_header* mh)
+{
+ const uint32_t cmd_count = mh->ncmds;
+ const struct load_command* const cmds = (struct load_command*)(((char*)mh) + sizeof(macho_header));
+ const struct load_command* cmd = cmds;
+ const struct version_min_command* versCmd;
+ for (uint32_t i = 0; i < cmd_count; ++i) {
+ switch ( cmd->cmd ) {
+ case LC_VERSION_MIN_MACOSX:
+ case LC_VERSION_MIN_IPHONEOS:
+ case LC_VERSION_MIN_TVOS:
+ case LC_VERSION_MIN_WATCHOS:
+ versCmd = (version_min_command*)cmd;
+ return versCmd->version;
+ }
+ cmd = (const struct load_command*)(((char*)cmd)+cmd->cmdsize);
+ }
+ return 0;
+}
+
+uint32_t ImageLoaderMachO::minOSVersion() const
+{
+ return ImageLoaderMachO::minOSVersion(machHeader());
+}
+
+
+void* ImageLoaderMachO::getThreadPC() const
+{
+ 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) {
+ if ( cmd->cmd == LC_MAIN ) {
+ entry_point_command* mainCmd = (entry_point_command*)cmd;
+ void* entry = (void*)(mainCmd->entryoff + (char*)fMachOData);
+ // <rdar://problem/8543820&9228031> verify entry point is in image
+ if ( this->containsAddress(entry) )
+ return entry;
+ else
+ throw "LC_MAIN entryoff is out of range";
+ }
+ cmd = (const struct load_command*)(((char*)cmd)+cmd->cmdsize);
+ }
+ return NULL;
+}
void* ImageLoaderMachO::getMain() const
@@ -683,30 +1067,31 @@
switch (cmd->cmd) {
case LC_UNIXTHREAD:
{
- #if __ppc__
- const ppc_thread_state_t* registers = (ppc_thread_state_t*)(((char*)cmd) + 16);
- return (void*)(registers->srr0 + fSlide);
- #elif __ppc64__
- const ppc_thread_state64_t* registers = (ppc_thread_state64_t*)(((char*)cmd) + 16);
- return (void*)(registers->srr0 + fSlide);
- #elif __i386__
+ #if __i386__
const i386_thread_state_t* registers = (i386_thread_state_t*)(((char*)cmd) + 16);
- return (void*)(registers->eip + fSlide);
+ void* entry = (void*)(registers->eip + fSlide);
#elif __x86_64__
const x86_thread_state64_t* registers = (x86_thread_state64_t*)(((char*)cmd) + 16);
- return (void*)(registers->rip + fSlide);
+ void* entry = (void*)(registers->rip + fSlide);
#elif __arm__
const arm_thread_state_t* registers = (arm_thread_state_t*)(((char*)cmd) + 16);
- return (void*)(registers->__pc + fSlide);
+ void* entry = (void*)(registers->__pc + fSlide);
+ #elif __arm64__
+ const arm_thread_state64_t* registers = (arm_thread_state64_t*)(((char*)cmd) + 16);
+ void* entry = (void*)(registers->__pc + fSlide);
#else
#warning need processor specific code
#endif
+ // <rdar://problem/8543820&9228031> verify entry point is in image
+ if ( this->containsAddress(entry) ) {
+ return entry;
+ }
}
break;
}
cmd = (const struct load_command*)(((char*)cmd)+cmd->cmdsize);
}
- return NULL;
+ throw "no valid entry point";
}
bool ImageLoaderMachO::needsAddedLibSystemDepency(unsigned int libCount, const macho_header* mh)
@@ -728,6 +1113,7 @@
case LC_LOAD_DYLIB:
case LC_LOAD_WEAK_DYLIB:
case LC_REEXPORT_DYLIB:
+ case LC_LOAD_UPWARD_DYLIB:
return false;
case LC_ID_DYLIB:
{
@@ -756,6 +1142,7 @@
lib->info.maxVersion = 0;
lib->required = false;
lib->reExported = false;
+ lib->upward = false;
}
else {
uint32_t index = 0;
@@ -767,6 +1154,7 @@
case LC_LOAD_DYLIB:
case LC_LOAD_WEAK_DYLIB:
case LC_REEXPORT_DYLIB:
+ case LC_LOAD_UPWARD_DYLIB:
{
const struct dylib_command* dylib = (struct dylib_command*)cmd;
DependentLibraryInfo* lib = &libs[index++];
@@ -777,6 +1165,7 @@
lib->info.maxVersion = dylib->dylib.current_version;
lib->required = (cmd->cmd != LC_LOAD_WEAK_DYLIB);
lib->reExported = (cmd->cmd == LC_REEXPORT_DYLIB);
+ lib->upward = (cmd->cmd == LC_LOAD_UPWARD_DYLIB);
}
break;
}
@@ -810,9 +1199,10 @@
for (uint32_t i = 0; i < cmd_count; ++i) {
switch (cmd->cmd) {
case LC_RPATH:
+ const char* pathToAdd = NULL;
const char* path = (char*)cmd + ((struct rpath_command*)cmd)->path.offset;
- if ( strncmp(path, "@loader_path/", 13) == 0 ) {
- if ( context.processIsRestricted && (context.mainExecutable == this) ) {
+ if ( (strncmp(path, "@loader_path", 12) == 0) && ((path[12] == '/') || (path[12] == '\0')) ) {
+ if ( context.processIsRestricted && !context.processRequiresLibraryValidation && (context.mainExecutable == this) ) {
dyld::warn("LC_RPATH %s in %s being ignored in restricted program because of @loader_path\n", path, this->getPath());
break;
}
@@ -821,15 +1211,14 @@
char newRealPath[strlen(resolvedPath) + strlen(path)];
strcpy(newRealPath, resolvedPath);
char* addPoint = strrchr(newRealPath,'/');
- if ( addPoint != NULL )
- strcpy(&addPoint[1], &path[13]);
- else
- strcpy(newRealPath, &path[13]);
- path = strdup(newRealPath);
+ if ( addPoint != NULL ) {
+ strcpy(addPoint, &path[12]);
+ pathToAdd = strdup(newRealPath);
+ }
}
}
- else if ( strncmp(path, "@executable_path/", 17) == 0 ) {
- if ( context.processIsRestricted ) {
+ else if ( (strncmp(path, "@executable_path", 16) == 0) && ((path[16] == '/') || (path[16] == '\0')) ) {
+ if ( context.processIsRestricted && !context.processRequiresLibraryValidation ) {
dyld::warn("LC_RPATH %s in %s being ignored in restricted program because of @executable_path\n", path, this->getPath());
break;
}
@@ -838,14 +1227,13 @@
char newRealPath[strlen(resolvedPath) + strlen(path)];
strcpy(newRealPath, resolvedPath);
char* addPoint = strrchr(newRealPath,'/');
- if ( addPoint != NULL )
- strcpy(&addPoint[1], &path[17]);
- else
- strcpy(newRealPath, &path[17]);
- path = strdup(newRealPath);
+ if ( addPoint != NULL ) {
+ strcpy(addPoint, &path[16]);
+ pathToAdd = strdup(newRealPath);
+ }
}
}
- else if ( (path[0] != '/') && context.processIsRestricted ) {
+ else if ( (path[0] != '/') && context.processIsRestricted && !context.processRequiresLibraryValidation ) {
dyld::warn("LC_RPATH %s in %s being ignored in restricted program because it is a relative path\n", path, this->getPath());
break;
}
@@ -855,31 +1243,33 @@
bool found = false;
for(const char** rp = context.rootPaths; *rp != NULL; ++rp) {
char newPath[PATH_MAX];
- strcpy(newPath, *rp);
- strcat(newPath, path);
+ strlcpy(newPath, *rp, PATH_MAX);
+ strlcat(newPath, path, PATH_MAX);
struct stat stat_buf;
if ( stat(newPath, &stat_buf) != -1 ) {
//dyld::log("combined DYLD_ROOT_PATH and LC_RPATH: %s\n", newPath);
- path = strdup(newPath);
+ pathToAdd = strdup(newPath);
found = true;
break;
}
}
if ( ! found ) {
// make copy so that all elements of 'paths' can be freed
- path = strdup(path);
+ pathToAdd = strdup(path);
}
}
else {
// make copy so that all elements of 'paths' can be freed
- path = strdup(path);
- }
- paths.push_back(path);
+ pathToAdd = strdup(path);
+ }
+ if ( pathToAdd != NULL )
+ paths.push_back(pathToAdd);
break;
}
cmd = (const struct load_command*)(((char*)cmd)+cmd->cmdsize);
}
}
+
bool ImageLoaderMachO::getUUID(uuid_t uuid) const
{
@@ -960,21 +1350,21 @@
#if TEXT_RELOC_SUPPORT
void ImageLoaderMachO::makeTextSegmentWritable(const LinkContext& context, bool writeable)
{
- int textSegmentIndex = 0;
for(unsigned int i=0; i < fSegmentsCount; ++i) {
- if ( strcmp(segName(i), "__TEXT") == 0 ) {
- textSegmentIndex = i;
- break;
- }
- }
-
- if ( writeable ) {
- segMakeWritable(textSegmentIndex, context);
- }
- else {
- segProtect(textSegmentIndex, context);
- sys_icache_invalidate((void*)segActualLoadAddress(textSegmentIndex), segSize(textSegmentIndex));
- }
+ if ( segExecutable(i) ) {
+ if ( writeable ) {
+ segMakeWritable(i, context);
+ }
+ else {
+ #if !__i386__ && !__x86_64__
+ // some processors require range to be invalidated before it is made executable
+ sys_icache_invalidate((void*)segActualLoadAddress(i), segSize(textSegmentIndex));
+ #endif
+ segProtect(i, context);
+ }
+ }
+ }
+
}
#endif
@@ -1004,14 +1394,18 @@
-uintptr_t ImageLoaderMachO::getExportedSymbolAddress(const Symbol* sym, const LinkContext& context, const ImageLoader* requestor) const
-{
- return this->getSymbolAddress(sym, requestor, context);
-}
-
-uintptr_t ImageLoaderMachO::getSymbolAddress(const Symbol* sym, const ImageLoader* requestor, const LinkContext& context) const
-{
- uintptr_t result = exportedSymbolAddress(sym);
+uintptr_t ImageLoaderMachO::getExportedSymbolAddress(const Symbol* sym, const LinkContext& context,
+ const ImageLoader* requestor, bool runResolver) const
+{
+ return this->getSymbolAddress(sym, requestor, context, runResolver);
+}
+
+uintptr_t ImageLoaderMachO::getSymbolAddress(const Symbol* sym, const ImageLoader* requestor,
+ const LinkContext& context, bool runResolver) const
+{
+ uintptr_t result = exportedSymbolAddress(context, sym, requestor, runResolver);
+ // check for interposing overrides
+ result = interposedAddress(context, result, requestor);
return result;
}
@@ -1149,9 +1543,14 @@
}
-void __attribute__((noreturn)) ImageLoaderMachO::throwSymbolNotFound(const char* symbol, const char* referencedFrom, const char* expectedIn)
-{
- dyld::throwf("Symbol not found: %s\n Referenced from: %s\n Expected in: %s\n", symbol, referencedFrom, expectedIn);
+void __attribute__((noreturn)) ImageLoaderMachO::throwSymbolNotFound(const LinkContext& context, const char* symbol,
+ const char* referencedFrom, const char* fromVersMismatch,
+ const char* expectedIn)
+{
+ // record values for possible use by CrashReporter or Finder
+ (*context.setErrorStrings)(dyld_error_kind_symbol_missing, referencedFrom, expectedIn, symbol);
+ dyld::throwf("Symbol not found: %s\n Referenced from: %s%s\n Expected in: %s\n",
+ symbol, referencedFrom, fromVersMismatch, expectedIn);
}
const mach_header* ImageLoaderMachO::machHeader() const
@@ -1196,6 +1595,9 @@
((targetImage != NULL) ? targetImage->getShortName() : "<weak>import-missing>"),
symbolName, (uintptr_t)location, value);
}
+#if LOG_BINDINGS
+// dyld::logBindings("%s: %s\n", targetImage->getShortName(), symbolName);
+#endif
// do actual update
uintptr_t* locationToFix = (uintptr_t*)location;
@@ -1216,7 +1618,7 @@
break;
case BIND_TYPE_TEXT_PCREL32:
loc32 = (uint32_t*)locationToFix;
- value32 = (uint32_t)newValue - (((uintptr_t)locationToFix) + 4);
+ value32 = (uint32_t)(newValue - (((uintptr_t)locationToFix) + 4));
if ( *loc32 != value32 )
*loc32 = value32;
break;
@@ -1236,15 +1638,13 @@
#if SUPPORT_OLD_CRT_INITIALIZATION
// first 16 bytes of "start" in crt1.o
-#if __ppc__
- static uint32_t sStandardEntryPointInstructions[4] = { 0x7c3a0b78, 0x3821fffc, 0x54210034, 0x38000000 };
-#elif __i386__
+#if __i386__
static uint8_t sStandardEntryPointInstructions[16] = { 0x6a, 0x00, 0x89, 0xe5, 0x83, 0xe4, 0xf0, 0x83, 0xec, 0x10, 0x8b, 0x5d, 0x04, 0x89, 0x5c, 0x24 };
#endif
#endif
struct DATAdyld {
- void* dyldLazyBinder; // filled in at launch by dyld to point into dyld to &stub_binding_helper_interface
+ void* dyldLazyBinder; // filled in at launch by dyld to point into dyld to &stub_binding_helper
void* dyldFuncLookup; // filled in at launch by dyld to point into dyld to &_dyld_func_lookup
// the following only exist in main executables built for 10.5 or later
ProgramVars vars;
@@ -1252,7 +1652,6 @@
// These are defined in dyldStartup.s
extern "C" void stub_binding_helper();
-extern "C" bool dyld_func_lookup(const char* name, uintptr_t* address);
void ImageLoaderMachO::setupLazyPointerHandler(const LinkContext& context)
@@ -1261,28 +1660,29 @@
const uint32_t cmd_count = mh->ncmds;
const struct load_command* const cmds = (struct load_command*)&fMachOData[sizeof(macho_header)];
const struct load_command* cmd;
- // set up __dyld section
- // optimizations:
- // 1) do nothing if image is in dyld shared cache and dyld loaded at same address as when cache built
- // 2) first read __dyld value, if already correct don't write, this prevents dirtying a page
- if ( !fInSharedCache || !context.dyldLoadedAtSameAddressNeededBySharedCache ) {
+ // There used to be some optimizations to skip this section scan, but we need to handle the
+ // __dyld section in libdyld.dylib, so everything needs to be scanned for now.
+ // <rdar://problem/10910062> CrashTracer: 1,295 crashes in bash at bash: getenv
+ if ( true ) {
cmd = cmds;
for (uint32_t i = 0; i < cmd_count; ++i) {
if ( cmd->cmd == LC_SEGMENT_COMMAND ) {
const struct macho_segment_command* seg = (struct macho_segment_command*)cmd;
- if ( strcmp(seg->segname, "__DATA") == 0 ) {
+ if ( strncmp(seg->segname, "__DATA", 6) == 0 ) {
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) {
if ( strcmp(sect->sectname, "__dyld" ) == 0 ) {
struct DATAdyld* dd = (struct DATAdyld*)(sect->addr + fSlide);
+ #if !__arm64__ && !__ARM_ARCH_7K__
if ( sect->size > offsetof(DATAdyld, dyldLazyBinder) ) {
if ( dd->dyldLazyBinder != (void*)&stub_binding_helper )
dd->dyldLazyBinder = (void*)&stub_binding_helper;
}
+ #endif // !__arm64__
if ( sect->size > offsetof(DATAdyld, dyldFuncLookup) ) {
- if ( dd->dyldFuncLookup != (void*)&dyld_func_lookup )
- dd->dyldFuncLookup = (void*)&dyld_func_lookup;
+ if ( dd->dyldFuncLookup != (void*)&_dyld_func_lookup )
+ dd->dyldFuncLookup = (void*)&_dyld_func_lookup;
}
if ( mh->filetype == MH_EXECUTE ) {
// there are two ways to get the program variables
@@ -1307,6 +1707,16 @@
#endif
}
}
+ else if ( mh->filetype == MH_DYLIB ) {
+ const char* installPath = this->getInstallPath();
+ if ( (installPath != NULL) && (strncmp(installPath, "/usr/lib/", 9) == 0) ) {
+ if ( sect->size > offsetof(DATAdyld, vars) ) {
+ // use ProgramVars from libdyld.dylib but tweak mh field to correct value
+ dd->vars.mh = context.mainExecutable->machHeader();
+ context.setNewProgramVars(dd->vars);
+ }
+ }
+ }
}
else if ( (strcmp(sect->sectname, "__program_vars" ) == 0) && (mh->filetype == MH_EXECUTE) ) {
// this is a Mac OS X 10.6 or later main executable
@@ -1333,22 +1743,22 @@
// lookup _NXArgc
sym = this->findExportedSymbol("_NXArgc", false, NULL);
if ( sym != NULL )
- vars.NXArgcPtr = (int*)this->getExportedSymbolAddress(sym, context, this);
+ vars.NXArgcPtr = (int*)this->getExportedSymbolAddress(sym, context, this, false);
// lookup _NXArgv
sym = this->findExportedSymbol("_NXArgv", false, NULL);
if ( sym != NULL )
- vars.NXArgvPtr = (const char***)this->getExportedSymbolAddress(sym, context, this);
+ vars.NXArgvPtr = (const char***)this->getExportedSymbolAddress(sym, context, this, false);
// lookup _environ
sym = this->findExportedSymbol("_environ", false, NULL);
if ( sym != NULL )
- vars.environPtr = (const char***)this->getExportedSymbolAddress(sym, context, this);
+ vars.environPtr = (const char***)this->getExportedSymbolAddress(sym, context, this, false);
// lookup __progname
sym = this->findExportedSymbol("___progname", false, NULL);
if ( sym != NULL )
- vars.__prognamePtr = (const char**)this->getExportedSymbolAddress(sym, context, this);
+ vars.__prognamePtr = (const char**)this->getExportedSymbolAddress(sym, context, this, false);
context.setNewProgramVars(vars);
}
@@ -1357,8 +1767,7 @@
bool ImageLoaderMachO::usablePrebinding(const LinkContext& context) const
{
// if prebound and loaded at prebound address, and all libraries are same as when this was prebound, then no need to bind
- if ( (this->isPrebindable() || fInSharedCache)
- && (this->getSlide() == 0)
+ if ( ((this->isPrebindable() && (this->getSlide() == 0)) || fInSharedCache)
&& this->usesTwoLevelNameSpace()
&& this->allDependentLibrariesAsWhenPreBound() ) {
// allow environment variables to disable prebinding
@@ -1389,8 +1798,12 @@
switch (cmd->cmd) {
case LC_ROUTINES_COMMAND:
Initializer func = (Initializer)(((struct macho_routines_command*)cmd)->init_address + fSlide);
+ // <rdar://problem/8543820&9228031> verify initializers are in image
+ if ( ! this->containsAddress((void*)func) ) {
+ dyld::throwf("initializer function %p not in mapped image for %s\n", func, this->getPath());
+ }
if ( context.verboseInit )
- dyld::log("dyld: calling -init function 0x%p in %s\n", func, this->getPath());
+ dyld::log("dyld: calling -init function %p in %s\n", func, this->getPath());
func(context.argc, context.argv, context.envp, context.apple, &context.programVars);
break;
}
@@ -1414,17 +1827,21 @@
const uint8_t type = sect->flags & SECTION_TYPE;
if ( type == S_MOD_INIT_FUNC_POINTERS ) {
Initializer* inits = (Initializer*)(sect->addr + fSlide);
- const uint32_t count = sect->size / sizeof(uintptr_t);
- for (uint32_t i=0; i < count; ++i) {
+ const size_t count = sect->size / sizeof(uintptr_t);
+ for (size_t i=0; i < count; ++i) {
Initializer func = inits[i];
+ // <rdar://problem/8543820&9228031> verify initializers are in image
+ if ( ! this->containsAddress((void*)func) ) {
+ dyld::throwf("initializer function %p not in mapped image for %s\n", func, this->getPath());
+ }
if ( context.verboseInit )
dyld::log("dyld: calling initializer function %p in %s\n", func, this->getPath());
func(context.argc, context.argv, context.envp, context.apple, &context.programVars);
}
}
}
- cmd = (const struct load_command*)(((char*)cmd)+cmd->cmdsize);
}
+ cmd = (const struct load_command*)(((char*)cmd)+cmd->cmdsize);
}
}
}
@@ -1466,11 +1883,17 @@
}
-void ImageLoaderMachO::doInitialization(const LinkContext& context)
-{
+bool ImageLoaderMachO::doInitialization(const LinkContext& context)
+{
+ CRSetCrashLogMessage2(this->getPath());
+
// mach-o has -init and static initializers
doImageInit(context);
doModInitFunctions(context);
+
+ CRSetCrashLogMessage2(NULL);
+
+ return (fHasDashInit || fHasInitializers);
}
bool ImageLoaderMachO::needsInitialization()
@@ -1500,9 +1923,13 @@
const uint8_t type = sect->flags & SECTION_TYPE;
if ( type == S_MOD_TERM_FUNC_POINTERS ) {
Terminator* terms = (Terminator*)(sect->addr + fSlide);
- const uint32_t count = sect->size / sizeof(uintptr_t);
- for (uint32_t i=count; i > 0; --i) {
+ const size_t count = sect->size / sizeof(uintptr_t);
+ for (size_t i=count; i > 0; --i) {
Terminator func = terms[i-1];
+ // <rdar://problem/8543820&9228031> verify terminators are in image
+ if ( ! this->containsAddress((void*)func) ) {
+ dyld::throwf("termination function %p not in mapped image for %s\n", func, this->getPath());
+ }
if ( context.verboseInit )
dyld::log("dyld: calling termination function %p in %s\n", func, this->getPath());
func();
@@ -1516,12 +1943,13 @@
}
-void ImageLoaderMachO::printStatistics(unsigned int imageCount)
-{
- ImageLoader::printStatistics(imageCount);
+void ImageLoaderMachO::printStatistics(unsigned int imageCount, const InitializerTimingList& timingInfo)
+{
+ ImageLoader::printStatistics(imageCount, timingInfo);
dyld::log("total symbol trie searches: %d\n", fgSymbolTrieSearchs);
dyld::log("total symbol table binary searches: %d\n", fgSymbolTableBinarySearchs);
- dyld::log("total images defining/using weak symbols: %u/%u\n", fgImagesHasWeakDefinitions, fgImagesRequiringCoalescing);
+ dyld::log("total images defining weak symbols: %u\n", fgImagesHasWeakDefinitions);
+ dyld::log("total images using weak symbols: %u\n", fgImagesRequiringCoalescing);
}
@@ -1537,7 +1965,13 @@
uintptr_t highAddr = 0;
for(unsigned int i=0, e=segmentCount(); i < e; ++i) {
const uintptr_t segLow = segPreferredLoadAddress(i);
- const uintptr_t segHigh = (segLow + segSize(i) + 4095) & -4096;
+ const uintptr_t segHigh = dyld_page_round(segLow + segSize(i));
+ if ( segLow < highAddr ) {
+ if ( dyld_page_size > 4096 )
+ dyld::throwf("can't map segments into 16KB pages");
+ else
+ dyld::throwf("overlapping segments");
+ }
if ( segLow < lowAddr )
lowAddr = segLow;
if ( segHigh > highAddr )
@@ -1557,7 +1991,7 @@
if ( strcmp(segName(i), "__PAGEZERO") == 0 )
continue;
if ( !reserveAddressRange(segPreferredLoadAddress(i), segSize(i)) )
- throw "can't map";
+ dyld::throwf("can't map unslidable segment %s to 0x%lX with size 0x%lX", segName(i), segPreferredLoadAddress(i), segSize(i));
}
}
else {
@@ -1573,15 +2007,17 @@
vm_size_t size = length;
// in PIE programs, load initial dylibs after main executable so they don't have fixed addresses either
if ( fgNextPIEDylibAddress != 0 ) {
- addr = fgNextPIEDylibAddress + (arc4random() & 0x3) * 4096; // add small random padding between dylibs
- kern_return_t r = vm_allocate(mach_task_self(), &addr, size, VM_FLAGS_FIXED);
+ // add small (0-3 pages) random padding between dylibs
+ addr = fgNextPIEDylibAddress + (__stack_chk_guard/fgNextPIEDylibAddress & (sizeof(long)-1))*dyld_page_size;
+ //dyld::log("padding 0x%08llX, guard=0x%08llX\n", (long long)(addr - fgNextPIEDylibAddress), (long long)(__stack_chk_guard));
+ kern_return_t r = vm_alloc(&addr, size, VM_FLAGS_FIXED | VM_MAKE_TAG(VM_MEMORY_DYLIB));
if ( r == KERN_SUCCESS ) {
fgNextPIEDylibAddress = addr + size;
return addr;
}
fgNextPIEDylibAddress = 0;
}
- kern_return_t r = vm_allocate(mach_task_self(), &addr, size, VM_FLAGS_ANYWHERE);
+ kern_return_t r = vm_alloc(&addr, size, VM_FLAGS_ANYWHERE | VM_MAKE_TAG(VM_MEMORY_DYLIB));
if ( r != KERN_SUCCESS )
throw "out of address space";
@@ -1592,7 +2028,7 @@
{
vm_address_t addr = start;
vm_size_t size = length;
- kern_return_t r = vm_allocate(mach_task_self(), &addr, size, false /*only this range*/);
+ kern_return_t r = vm_alloc(&addr, size, VM_FLAGS_FIXED | VM_MAKE_TAG(VM_MEMORY_DYLIB));
if ( r != KERN_SUCCESS )
return false;
return true;
@@ -1604,16 +2040,22 @@
{
// find address range for image
intptr_t slide = this->assignSegmentAddresses(context);
- if ( context.verboseMapping )
- dyld::log("dyld: Mapping %s\n", this->getPath());
+ if ( context.verboseMapping ) {
+ if ( offsetInFat != 0 )
+ dyld::log("dyld: Mapping %s (slice offset=%llu)\n", this->getPath(), (unsigned long long)offsetInFat);
+ else
+ dyld::log("dyld: Mapping %s\n", this->getPath());
+ }
// map in all segments
for(unsigned int i=0, e=segmentCount(); i < e; ++i) {
vm_offset_t fileOffset = segFileOffset(i) + offsetInFat;
vm_size_t size = segFileSize(i);
- void* requestedLoadAddress = (void*)(segPreferredLoadAddress(i) + slide);
+ uintptr_t requestedLoadAddress = segPreferredLoadAddress(i) + slide;
int protection = 0;
if ( !segUnaccessible(i) ) {
- if ( segExecutable(i) )
+ // If has text-relocs, don't set x-bit initially.
+ // Instead set it later after text-relocs have been done.
+ if ( segExecutable(i) && !(segHasRebaseFixUps(i) && (slide != 0)) )
protection |= PROT_EXEC;
if ( segReadable(i) )
protection |= PROT_READ;
@@ -1631,19 +2073,20 @@
dyld::throwf("truncated mach-o error: segment %s extends to %llu which is past end of file %llu",
segName(i), (uint64_t)(fileOffset+size), fileLen);
}
- void* loadAddress = mmap(requestedLoadAddress, size, protection, MAP_FIXED | MAP_PRIVATE, fd, fileOffset);
+ void* loadAddress = xmmap((void*)requestedLoadAddress, size, protection, MAP_FIXED | MAP_PRIVATE, fd, fileOffset);
if ( loadAddress == ((void*)(-1)) ) {
dyld::throwf("mmap() error %d at address=0x%08lX, size=0x%08lX segment=%s in Segment::map() mapping %s",
- errno, (uintptr_t)requestedLoadAddress, (uintptr_t)size, segName(i), getPath());
+ errno, requestedLoadAddress, (uintptr_t)size, segName(i), getPath());
}
}
// update stats
++ImageLoader::fgTotalSegmentsMapped;
ImageLoader::fgTotalBytesMapped += size;
if ( context.verboseMapping )
- dyld::log("%18s at 0x%08lX->0x%08lX with permissions %c%c%c\n", segName(i), (uintptr_t)requestedLoadAddress, (uintptr_t)((char*)requestedLoadAddress+size-1),
+ dyld::log("%18s at 0x%08lX->0x%08lX with permissions %c%c%c\n", segName(i), requestedLoadAddress, requestedLoadAddress+size-1,
(protection & PROT_READ) ? 'r' : '.', (protection & PROT_WRITE) ? 'w' : '.', (protection & PROT_EXEC) ? 'x' : '.' );
}
+
// update slide to reflect load location
this->setSlide(slide);
}
@@ -1689,8 +2132,10 @@
vm_size_t size = segSize(segIndex);
const bool setCurrentPermissions = false;
kern_return_t r = vm_protect(mach_task_self(), addr, size, setCurrentPermissions, protection);
- if ( r != KERN_SUCCESS )
- throw "can't set vm permissions for mapped segment";
+ if ( r != KERN_SUCCESS ) {
+ dyld::throwf("vm_protect(0x%08llX, 0x%08llX, false, 0x%02X) failed, result=%d for segment %s in %s",
+ (long long)addr, (long long)size, protection, r, segName(segIndex), this->getPath());
+ }
if ( context.verboseMapping ) {
dyld::log("%18s at 0x%08lX->0x%08lX altered permissions to %c%c%c\n", segName(segIndex), (uintptr_t)addr, (uintptr_t)addr+size-1,
(protection & PROT_READ) ? 'r' : '.', (protection & PROT_WRITE) ? 'w' : '.', (protection & PROT_EXEC) ? 'x' : '.' );
@@ -1703,11 +2148,13 @@
vm_size_t size = segSize(segIndex);
const bool setCurrentPermissions = false;
vm_prot_t protection = VM_PROT_WRITE | VM_PROT_READ;
- if ( segExecutable(segIndex) )
+ if ( segExecutable(segIndex) && !segHasRebaseFixUps(segIndex) )
protection |= VM_PROT_EXECUTE;
kern_return_t r = vm_protect(mach_task_self(), addr, size, setCurrentPermissions, protection);
- if ( r != KERN_SUCCESS )
- throw "can't set vm permissions for mapped segment";
+ if ( r != KERN_SUCCESS ) {
+ dyld::throwf("vm_protect(0x%08llX, 0x%08llX, false, 0x%02X) failed, result=%d for segment %s in %s",
+ (long long)addr, (long long)size, protection, r, segName(segIndex), this->getPath());
+ }
if ( context.verboseMapping ) {
dyld::log("%18s at 0x%08lX->0x%08lX altered permissions to %c%c%c\n", segName(segIndex), (uintptr_t)addr, (uintptr_t)addr+size-1,
(protection & PROT_READ) ? 'r' : '.', (protection & PROT_WRITE) ? 'w' : '.', (protection & PROT_EXEC) ? 'x' : '.' );