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--- dyld/dyld-95.3/src/dyldInitialization.cpp
+++ dyld/dyld-46.12/src/dyldInitialization.cpp
@@ -22,11 +22,8 @@
* @APPLE_LICENSE_HEADER_END@
*/
-#define __STDC_LIMIT_MACROS
-#include <stdint.h>
#include <stddef.h>
#include <string.h>
-#include <stdlib.h>
#include <mach/mach.h>
#include <mach-o/loader.h>
#include <mach-o/ldsyms.h>
@@ -38,11 +35,6 @@
#include <mach-o/x86_64/reloc.h>
#endif
#include "dyld.h"
-
-#ifndef MH_PIE
- #define MH_PIE 0x200000
-#endif
-
#if __LP64__
#define macho_header mach_header_64
@@ -63,10 +55,6 @@
#else
#define POINTER_RELOC GENERIC_RELOC_VANILLA
#endif
-
-// from dyld.cpp
-namespace dyld { extern bool isRosetta(); };
-
//
// Code to bootstrap dyld into a runnable state
@@ -206,7 +194,7 @@
vm_size_t size = seg->vmsize;
const bool setCurrentPermissions = false;
vm_protect(mach_task_self(), addr, size, setCurrentPermissions, seg->initprot);
- //dyld::log("dyld: segment %s, 0x%08X -> 0x%08X, set to %d\n", seg->segname, addr, addr+size-1, seg->initprot);
+ //fprintf(stderr, "dyld: segment %s, 0x%08X -> 0x%08X, set to %d\n", seg->segname, addr, addr+size-1, seg->initprot);
}
break;
}
@@ -215,113 +203,8 @@
}
-
-//
-// re-map the main executable to a new random address
-//
-static const struct mach_header* randomizeExecutableLoadAddress(const struct mach_header* orgMH, uintptr_t* appsSlide)
-{
-#if __ppc__
- // don't slide PIE programs running under rosetta
- if ( dyld::isRosetta() )
- return orgMH;
-#endif
- // count segments
- uint32_t segCount = 0;
- const uint32_t cmd_count = orgMH->ncmds;
- const struct load_command* const cmds = (struct load_command*)(((char*)orgMH)+sizeof(macho_header));
- const struct load_command* cmd = cmds;
- for (uint32_t i = 0; i < cmd_count; ++i) {
- if ( cmd->cmd == LC_SEGMENT_COMMAND ) {
- const struct macho_segment_command* segCmd = (struct macho_segment_command*)cmd;
- // page-zero and custom stacks don't move
- if ( (strcmp(segCmd->segname, "__PAGEZERO") != 0) && (strcmp(segCmd->segname, "__UNIXSTACK") != 0) )
- ++segCount;
- }
- cmd = (const struct load_command*)(((char*)cmd)+cmd->cmdsize);
- }
-
- // make copy of segment info
- macho_segment_command segs[segCount];
- uint32_t index = 0;
- uintptr_t highestAddressUsed = 0;
- uintptr_t lowestAddressUsed = UINTPTR_MAX;
- cmd = cmds;
- for (uint32_t i = 0; i < cmd_count; ++i) {
- if ( cmd->cmd == LC_SEGMENT_COMMAND ) {
- const struct macho_segment_command* segCmd = (struct macho_segment_command*)cmd;
- if ( (strcmp(segCmd->segname, "__PAGEZERO") != 0) && (strcmp(segCmd->segname, "__UNIXSTACK") != 0) ) {
- segs[index++] = *segCmd;
- if ( (segCmd->vmaddr + segCmd->vmsize) > highestAddressUsed )
- highestAddressUsed = ((segCmd->vmaddr + segCmd->vmsize) + 4095) & -4096;
- if ( segCmd->vmaddr < lowestAddressUsed )
- lowestAddressUsed = segCmd->vmaddr;
- // do nothing if kernel has already randomized load address
- if ( (strcmp(segCmd->segname, "__TEXT") == 0) && (segCmd->vmaddr != (uintptr_t)orgMH) )
- return orgMH;
- }
- }
- cmd = (const struct load_command*)(((char*)cmd)+cmd->cmdsize);
- }
-
- // choose a random new base address
-#if __LP64__
- uintptr_t highestAddressPossible = highestAddressUsed + 0x100000000ULL;
-#else
- uintptr_t highestAddressPossible = 0x80000000;
-#endif
- uintptr_t sizeNeeded = highestAddressUsed-lowestAddressUsed;
- if ( (highestAddressPossible-sizeNeeded) < highestAddressUsed ) {
- // new and old segments will overlap
- // need better algorithm for remapping
- // punt and don't re-map
- return orgMH;
- }
- uintptr_t possibleRange = (highestAddressPossible-sizeNeeded) - highestAddressUsed;
- uintptr_t newBaseAddress = highestAddressUsed + ((arc4random() % possibleRange) & -4096);
-
- vm_address_t addr = newBaseAddress;
- // reserve new address range
- if ( vm_allocate(mach_task_self(), &addr, sizeNeeded, VM_FLAGS_FIXED) == KERN_SUCCESS ) {
- // copy each segment to new address
- for (uint32_t i = 0; i < segCount; ++i) {
- uintptr_t newSegAddress = segs[i].vmaddr - lowestAddressUsed + newBaseAddress;
- if ( (vm_copy(mach_task_self(), segs[i].vmaddr, segs[i].vmsize, newSegAddress) != KERN_SUCCESS)
- || (vm_protect(mach_task_self(), newSegAddress, segs[i].vmsize, true, segs[i].maxprot) != KERN_SUCCESS)
- || (vm_protect(mach_task_self(), newSegAddress, segs[i].vmsize, false, segs[i].initprot) != KERN_SUCCESS) ) {
- // can't copy so dealloc new region and run with original base address
- vm_deallocate(mach_task_self(), newBaseAddress, sizeNeeded);
- dyld::warn("could not relocate position independent exectable\n");
- return orgMH;
- }
- }
- // unmap original segments
- vm_deallocate(mach_task_self(), lowestAddressUsed, highestAddressUsed-lowestAddressUsed);
-
- // run with newly mapped executable
- *appsSlide = newBaseAddress - lowestAddressUsed;
- return (const struct mach_header*)newBaseAddress;
- }
-
- // can't get new range, so don't slide to random address
- return orgMH;
-}
-
-
extern "C" void dyld_exceptions_init(const struct macho_header*, uintptr_t slide); // in dyldExceptions.cpp
extern "C" void mach_init();
-
-//
-// _pthread_keys is partitioned in a lower part that dyld will use; libSystem
-// will use the upper part. We set __pthread_tsd_first to 1 as the start of
-// the lower part. Libc will take #1 and c++ exceptions will take #2. There
-// is one free key=3 left.
-//
-extern "C" {
- extern int __pthread_tsd_first;
- extern void _pthread_keys_init();
-}
-
//
// This is code to bootstrap dyld. This work in normally done for a program by dyld and crt.
@@ -338,12 +221,6 @@
rebaseDyld(dyldsMachHeader, slide);
}
- uintptr_t appsSlide = 0;
-
- // set pthread keys to dyld range
- __pthread_tsd_first = 1;
- _pthread_keys_init();
-
// enable C++ exceptions to work inside dyld
dyld_exceptions_init(dyldsMachHeader, slide);
@@ -364,12 +241,8 @@
// run all C++ initializers inside dyld
runDyldInitializers(dyldsMachHeader, slide, argc, argv, envp, apple);
- // if main executable was linked -pie, then randomize its load address
- if ( appsMachHeader->flags & MH_PIE )
- appsMachHeader = randomizeExecutableLoadAddress(appsMachHeader, &appsSlide);
-
// now that we are done bootstrapping dyld, call dyld's main
- return dyld::_main(appsMachHeader, appsSlide, argc, argv, envp, apple);
+ return dyld::_main(appsMachHeader, argc, argv, envp, apple);
}