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--- dyld/dyld-46.12/src/dyldInitialization.cpp
+++ dyld/dyld-43/src/dyldInitialization.cpp
@@ -31,9 +31,6 @@
#if __ppc__ || __ppc64__
#include <mach-o/ppc/reloc.h>
#endif
-#if __x86_64__
- #include <mach-o/x86_64/reloc.h>
-#endif
#include "dyld.h"
#if __LP64__
@@ -50,11 +47,6 @@
#define RELOC_SIZE 2
#endif
-#if __x86_64__
- #define POINTER_RELOC X86_64_RELOC_UNSIGNED
-#else
- #define POINTER_RELOC GENERIC_RELOC_VANILLA
-#endif
//
// Code to bootstrap dyld into a runnable state
@@ -102,22 +94,20 @@
}
}
+
//
// If the kernel does not load dyld at its preferred address, we need to apply
// fixups to various initialized parts of the __DATA segment
//
static void rebaseDyld(const struct macho_header* mh, intptr_t slide)
{
- // rebase non-lazy pointers (which all point internal to dyld, since dyld uses no shared libraries)
- // and get interesting pointers into dyld
+ // get interesting pointers into dyld
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 macho_segment_command* linkEditSeg = NULL;
-#if __x86_64__
- const struct macho_segment_command* firstWritableSeg = NULL;
-#endif
const struct dysymtab_command* dynamicSymbolTable = NULL;
+ const struct macho_section* nonLazySection = NULL;
for (uint32_t i = 0; i < cmd_count; ++i) {
switch (cmd->cmd) {
case LC_SEGMENT_COMMAND:
@@ -129,19 +119,9 @@
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 ) {
- // rebase non-lazy pointers (which all point internal to dyld, since dyld uses no shared libraries)
- const uint32_t pointerCount = sect->size / sizeof(uintptr_t);
- uintptr_t* const symbolPointers = (uintptr_t*)(sect->addr + slide);
- for (uint32_t j=0; j < pointerCount; ++j) {
- symbolPointers[j] += slide;
- }
- }
+ if ( type == S_NON_LAZY_SYMBOL_POINTERS )
+ nonLazySection = sect;
}
-#if __x86_64__
- if ( (firstWritableSeg == NULL) && (seg->initprot & VM_PROT_WRITE) )
- firstWritableSeg = seg;
-#endif
}
break;
case LC_DYSYMTAB:
@@ -152,29 +132,50 @@
}
// use reloc's to rebase all random data pointers
-#if __x86_64__
- const uintptr_t relocBase = firstWritableSeg->vmaddr + slide;
-#else
const uintptr_t relocBase = (uintptr_t)mh;
-#endif
const relocation_info* const relocsStart = (struct relocation_info*)(linkEditSeg->vmaddr + slide + dynamicSymbolTable->locreloff - linkEditSeg->fileoff);
const relocation_info* const relocsEnd = &relocsStart[dynamicSymbolTable->nlocrel];
for (const relocation_info* reloc=relocsStart; reloc < relocsEnd; ++reloc) {
- #if __ppc__ || __ppc64__ || __i36__
- if ( (reloc->r_address & R_SCATTERED) != 0 )
- throw "scattered relocation in dyld";
- #endif
- if ( reloc->r_length != RELOC_SIZE )
- throw "relocation in dyld has wrong size";
-
- if ( reloc->r_type != POINTER_RELOC )
- throw "relocation in dyld has wrong type";
-
- // update pointer by amount dyld slid
- *((uintptr_t*)(reloc->r_address + relocBase)) += slide;
- }
-}
-
+ if ( (reloc->r_address & R_SCATTERED) == 0 ) {
+ if (reloc->r_length == RELOC_SIZE) {
+ switch(reloc->r_type) {
+ case GENERIC_RELOC_VANILLA:
+ *((uintptr_t*)(reloc->r_address + relocBase)) += slide;
+ break;
+ }
+ }
+ }
+ else {
+ const struct scattered_relocation_info* sreloc = (struct scattered_relocation_info*)reloc;
+ if (sreloc->r_length == RELOC_SIZE) {
+ uintptr_t* locationToFix = (uintptr_t*)(sreloc->r_address + relocBase);
+ switch(sreloc->r_type) {
+ case GENERIC_RELOC_VANILLA:
+ #if __ppc__ || __ppc64__
+ case PPC_RELOC_PB_LA_PTR:
+ #elif __i386__
+ case GENERIC_RELOC_PB_LA_PTR:
+ #endif
+ // Note the use of PB_LA_PTR is unique here. Seems like ld should strip out all lazy pointers
+ // but it does not. But, since all lazy-pointers point within dyld, they can be slid too
+ *locationToFix += slide;
+ break;
+ }
+ }
+ }
+ }
+
+ // rebase non-lazy pointers (which all point internal to dyld, since dyld uses no shared libraries)
+ if ( nonLazySection != NULL ) {
+ const uint32_t pointerCount = nonLazySection->size / sizeof(uintptr_t);
+ uintptr_t* const symbolPointers = (uintptr_t*)(nonLazySection->addr + slide);
+ for (uint32_t j=0; j < pointerCount; ++j) {
+ symbolPointers[j] += slide;
+ }
+ }
+
+
+}
//
// For some reason the kernel loads dyld with __TEXT and __LINKEDIT writable