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am d4e9f076: Merge "Clean up linker architecture macros."

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* commit 'd4e9f076d621dcf6450acba178e65d63c076ae6e':
  Clean up linker architecture macros.
This commit is contained in:
Elliott Hughes 2013-10-28 11:06:47 -07:00 committed by Android Git Automerger
commit c98827e70a
8 changed files with 147 additions and 174 deletions
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42
libthread_db/libthread_db.c
View File

@ -79,29 +79,8 @@ static td_thrhandle_t gEventMsgHandle;
static int static int
_event_getmsg_helper(td_thrhandle_t const * handle, void * bkpt_addr) _event_getmsg_helper(td_thrhandle_t const * handle, void * bkpt_addr)
{ {
void * pc; #if defined(__arm__)
void* pc = (void *)ptrace(PTRACE_PEEKUSR, handle->tid, (void *)60 /* r15/pc */, NULL);
#ifdef __i386__
/* Get the eip from offset 12*4 = 48 as defined in the struct
* user_regs_struct in user_32.h
*/
pc = (void *)ptrace(PTRACE_PEEKUSR, handle->tid, (void *)48 /* eip */, NULL);
/* FIXME - pc is a non-decremented breakpoint address, hence the
* addition of 1 on test. This seems to work for the thread hook
* function in libc.so but should be properly fixed.
*/
if (pc == ((int)bkpt_addr + 1)) {
/* The hook function takes the id of the new thread as it's first
* param, so grab it from ecx at offset 4 in struct user_regs_struct
* (using fastcall convention for x86)
*/
gEventMsgHandle.pid = ptrace(PTRACE_PEEKUSR, handle->tid, (void *)4 /* ecx */, NULL);
gEventMsgHandle.tid = gEventMsgHandle.pid;
return 0x42;
}
#elif defined(__arm__)
pc = (void *)ptrace(PTRACE_PEEKUSR, handle->tid, (void *)60 /* r15/pc */, NULL);
if (pc == bkpt_addr) { if (pc == bkpt_addr) {
// The hook function takes the id of the new thread as it's first param, // The hook function takes the id of the new thread as it's first param,
// so grab it from r0. // so grab it from r0.
@ -109,8 +88,23 @@ _event_getmsg_helper(td_thrhandle_t const * handle, void * bkpt_addr)
gEventMsgHandle.tid = gEventMsgHandle.pid; gEventMsgHandle.tid = gEventMsgHandle.pid;
return 0x42; return 0x42;
} }
#elif defined(__i386__)
// Get the eip from offset 12*4 = 48 as defined in the struct
// user_regs_struct in user_32.h
void* pc = (void *)ptrace(PTRACE_PEEKUSR, handle->tid, (void *)48 /* eip */, NULL);
// FIXME - pc is a non-decremented breakpoint address, hence the
// addition of 1 on test. This seems to work for the thread hook
// function in libc.so but should be properly fixed.
if (pc == ((int)bkpt_addr + 1)) {
// The hook function takes the id of the new thread as it's first
// param, so grab it from ecx at offset 4 in struct user_regs_struct
// (using fastcall convention for x86)
gEventMsgHandle.pid = ptrace(PTRACE_PEEKUSR, handle->tid, (void *)4 /* ecx */, NULL);
gEventMsgHandle.tid = gEventMsgHandle.pid;
return 0x42;
}
#elif defined(__mips__) #elif defined(__mips__)
pc = (void *)ptrace(PTRACE_PEEKUSR, handle->tid, (void *)(64*4) /* pc */, NULL); void* pc = (void *)ptrace(PTRACE_PEEKUSR, handle->tid, (void *)(64*4) /* pc */, NULL);
if (pc == bkpt_addr) { if (pc == bkpt_addr) {
// The hook function takes the id of the new thread as it's first param, // The hook function takes the id of the new thread as it's first param,
// so grab it from a0 // so grab it from a0

5
linker/Android.mk
View File

@ -33,11 +33,6 @@ LOCAL_CPPFLAGS += \
# We need to access Bionic private headers in the linker. # We need to access Bionic private headers in the linker.
LOCAL_CFLAGS += -I$(LOCAL_PATH)/../libc/ LOCAL_CFLAGS += -I$(LOCAL_PATH)/../libc/
# Make the target architecture available at compile time.
# TODO: do we really need this? why not just use __aarch64__, __arm__, __i386__, __mips__, __x86_64__?
uppercase_target_arch := $(shell tr '[:lower:]' '[:upper:]' <<< $(TARGET_ARCH))
LOCAL_CFLAGS += -DANDROID_$(uppercase_target_arch)_LINKER
ifeq ($(TARGET_ARCH),$(filter $(TARGET_ARCH),x86_64)) ifeq ($(TARGET_ARCH),$(filter $(TARGET_ARCH),x86_64))
LOCAL_MODULE := linker64 LOCAL_MODULE := linker64
else else

2
linker/debugger.cpp
View File

@ -235,7 +235,7 @@ void debuggerd_signal_handler(int n, siginfo_t* info, void*) {
case SIGABRT: case SIGABRT:
case SIGFPE: case SIGFPE:
case SIGPIPE: case SIGPIPE:
#ifdef SIGSTKFLT #if defined(SIGSTKFLT)
case SIGSTKFLT: case SIGSTKFLT:
#endif #endif
(void) tgkill(getpid(), gettid(), n); (void) tgkill(getpid(), gettid(), n);

14
linker/dlfcn.cpp
View File

@ -143,12 +143,12 @@ int dlclose(void* handle) {
return do_dlclose(reinterpret_cast<soinfo*>(handle)); return do_dlclose(reinterpret_cast<soinfo*>(handle));
} }
#if defined(ANDROID_ARM_LINKER) #if defined(__arm__)
// 0000000 00011111 111112 22222222 2333333 3333444444444455555555556666666 6667777777777888 8888888 // 0000000 00011111 111112 22222222 2333333 3333444444444455555555556666666 6667777777777888 8888888
// 0123456 78901234 567890 12345678 9012345 6789012345678901234567890123456 7890123456789012 3456789 // 0123456 78901234 567890 12345678 9012345 6789012345678901234567890123456 7890123456789012 3456789
#define ANDROID_LIBDL_STRTAB \ #define ANDROID_LIBDL_STRTAB \
"dlopen\0dlclose\0dlsym\0dlerror\0dladdr\0android_update_LD_LIBRARY_PATH\0dl_iterate_phdr\0dl_unwind_find_exidx\0" "dlopen\0dlclose\0dlsym\0dlerror\0dladdr\0android_update_LD_LIBRARY_PATH\0dl_iterate_phdr\0dl_unwind_find_exidx\0"
#elif defined(ANDROID_MIPS_LINKER) || defined(ANDROID_X86_LINKER) || defined(ANDROID_X86_64_LINKER) #elif defined(__i386__) || defined(__mips__) || defined(__x86_64__)
// 0000000 00011111 111112 22222222 2333333 3333444444444455555555556666666 6667 // 0000000 00011111 111112 22222222 2333333 3333444444444455555555556666666 6667
// 0123456 78901234 567890 12345678 9012345 6789012345678901234567890123456 7890 // 0123456 78901234 567890 12345678 9012345 6789012345678901234567890123456 7890
#define ANDROID_LIBDL_STRTAB \ #define ANDROID_LIBDL_STRTAB \
@ -195,7 +195,7 @@ static Elf_Sym gLibDlSymtab[] = {
ELF_SYM_INITIALIZER(29, &dladdr, 1), ELF_SYM_INITIALIZER(29, &dladdr, 1),
ELF_SYM_INITIALIZER(36, &android_update_LD_LIBRARY_PATH, 1), ELF_SYM_INITIALIZER(36, &android_update_LD_LIBRARY_PATH, 1),
ELF_SYM_INITIALIZER(67, &dl_iterate_phdr, 1), ELF_SYM_INITIALIZER(67, &dl_iterate_phdr, 1),
#if defined(ANDROID_ARM_LINKER) #if defined(__arm__)
ELF_SYM_INITIALIZER(83, &dl_unwind_find_exidx, 1), ELF_SYM_INITIALIZER(83, &dl_unwind_find_exidx, 1),
#endif #endif
}; };
@ -219,7 +219,7 @@ static Elf_Sym gLibDlSymtab[] = {
// Note that adding any new symbols here requires // Note that adding any new symbols here requires
// stubbing them out in libdl. // stubbing them out in libdl.
static unsigned gLibDlBuckets[1] = { 1 }; static unsigned gLibDlBuckets[1] = { 1 };
#if defined(ANDROID_ARM_LINKER) #if defined(__arm__)
static unsigned gLibDlChains[9] = { 0, 2, 3, 4, 5, 6, 7, 8, 0 }; static unsigned gLibDlChains[9] = { 0, 2, 3, 4, 5, 6, 7, 8, 0 };
#else #else
static unsigned gLibDlChains[8] = { 0, 2, 3, 4, 5, 6, 7, 0 }; static unsigned gLibDlChains[8] = { 0, 2, 3, 4, 5, 6, 7, 0 };
@ -257,7 +257,7 @@ soinfo libdl_info = {
.bucket = gLibDlBuckets, .bucket = gLibDlBuckets,
.chain = gLibDlChains, .chain = gLibDlChains,
#if defined(ANDROID_X86_64_LINKER) #if defined(USE_RELA)
.plt_rela = 0, .plt_rela = 0,
.plt_rela_count = 0, .plt_rela_count = 0,
.rela = 0, .rela = 0,
@ -282,10 +282,10 @@ soinfo libdl_info = {
.init_func = 0, .init_func = 0,
.fini_func = 0, .fini_func = 0,
#if defined(ANDROID_ARM_LINKER) #if defined(__arm__)
.ARM_exidx = 0, .ARM_exidx = 0,
.ARM_exidx_count = 0, .ARM_exidx_count = 0,
#elif defined(ANDROID_MIPS_LINKER) #elif defined(__mips__)
.mips_symtabno = 0, .mips_symtabno = 0,
.mips_local_gotno = 0, .mips_local_gotno = 0,
.mips_gotsym = 0, .mips_gotsym = 0,

215
linker/linker.cpp
View File

@ -90,7 +90,7 @@ static soinfo* sonext = &libdl_info;
static soinfo* somain; /* main process, always the one after libdl_info */ static soinfo* somain; /* main process, always the one after libdl_info */
static const char* const gSoPaths[] = { static const char* const gSoPaths[] = {
#if __LP64__ #if defined(__LP64__)
"/vendor/lib64", "/vendor/lib64",
"/system/lib64", "/system/lib64",
#else #else
@ -393,7 +393,7 @@ static void parse_LD_PRELOAD(const char* path) {
gLdPreloadsBuffer, sizeof(gLdPreloadsBuffer), LDPRELOAD_MAX); gLdPreloadsBuffer, sizeof(gLdPreloadsBuffer), LDPRELOAD_MAX);
} }
#ifdef ANDROID_ARM_LINKER #if defined(__arm__)
/* For a given PC, find the .so that it belongs to. /* For a given PC, find the .so that it belongs to.
* Returns the base address of the .ARM.exidx section * Returns the base address of the .ARM.exidx section
@ -521,7 +521,7 @@ static Elf_Sym* soinfo_do_lookup(soinfo* si, const char* name, soinfo** lsi, soi
} }
/* Look for symbols in the local scope (the object who is /* Look for symbols in the local scope (the object who is
* searching). This happens with C++ templates on i386 for some * searching). This happens with C++ templates on x86 for some
* reason. * reason.
* *
* Notes on weak symbols: * Notes on weak symbols:
@ -845,7 +845,7 @@ int do_dlclose(soinfo* si) {
return result; return result;
} }
#if defined(ANDROID_X86_64_LINKER) #if defined(USE_RELA)
static int soinfo_relocate_a(soinfo* si, Elf_Rela* rela, unsigned count, soinfo* needed[]) { static int soinfo_relocate_a(soinfo* si, Elf_Rela* rela, unsigned count, soinfo* needed[]) {
Elf_Sym* symtab = si->symtab; Elf_Sym* symtab = si->symtab;
const char* strtab = si->strtab; const char* strtab = si->strtab;
@ -888,16 +888,17 @@ static int soinfo_relocate_a(soinfo* si, Elf_Rela* rela, unsigned count, soinfo*
*/ */
switch (type) { switch (type) {
#if defined(__x86_64__)
case R_X86_64_JUMP_SLOT: case R_X86_64_JUMP_SLOT:
case R_X86_64_GLOB_DAT: case R_X86_64_GLOB_DAT:
case R_X86_64_32: case R_X86_64_32:
case R_X86_64_RELATIVE: case R_X86_64_RELATIVE:
// No need to do anything. // No need to do anything.
break; break;
case R_X86_64_PC32: case R_X86_64_PC32:
sym_addr = reloc; sym_addr = reloc;
break; break;
#endif
default: default:
DL_ERR("unknown weak reloc type %d @ %p (%d)", type, rela, (int) (rela - start)); DL_ERR("unknown weak reloc type %d @ %p (%d)", type, rela, (int) (rela - start));
@ -913,6 +914,7 @@ static int soinfo_relocate_a(soinfo* si, Elf_Rela* rela, unsigned count, soinfo*
} }
switch (type) { switch (type) {
#if defined(__x86_64__)
case R_X86_64_JUMP_SLOT: case R_X86_64_JUMP_SLOT:
count_relocation(kRelocAbsolute); count_relocation(kRelocAbsolute);
MARK(rela->r_offset); MARK(rela->r_offset);
@ -938,7 +940,6 @@ static int soinfo_relocate_a(soinfo* si, Elf_Rela* rela, unsigned count, soinfo*
static_cast<size_t>(si->base)); static_cast<size_t>(si->base));
*reinterpret_cast<Elf_Addr*>(reloc) = si->base + rela->r_addend; *reinterpret_cast<Elf_Addr*>(reloc) = si->base + rela->r_addend;
break; break;
case R_X86_64_32: case R_X86_64_32:
count_relocation(kRelocRelative); count_relocation(kRelocRelative);
MARK(rela->r_offset); MARK(rela->r_offset);
@ -946,7 +947,6 @@ static int soinfo_relocate_a(soinfo* si, Elf_Rela* rela, unsigned count, soinfo*
static_cast<size_t>(sym_addr), sym_name); static_cast<size_t>(sym_addr), sym_name);
*reinterpret_cast<Elf_Addr*>(reloc) = sym_addr + rela->r_addend; *reinterpret_cast<Elf_Addr*>(reloc) = sym_addr + rela->r_addend;
break; break;
case R_X86_64_64: case R_X86_64_64:
count_relocation(kRelocRelative); count_relocation(kRelocRelative);
MARK(rela->r_offset); MARK(rela->r_offset);
@ -954,7 +954,6 @@ static int soinfo_relocate_a(soinfo* si, Elf_Rela* rela, unsigned count, soinfo*
static_cast<size_t>(sym_addr), sym_name); static_cast<size_t>(sym_addr), sym_name);
*reinterpret_cast<Elf_Addr*>(reloc) = sym_addr + rela->r_addend; *reinterpret_cast<Elf_Addr*>(reloc) = sym_addr + rela->r_addend;
break; break;
case R_X86_64_PC32: case R_X86_64_PC32:
count_relocation(kRelocRelative); count_relocation(kRelocRelative);
MARK(rela->r_offset); MARK(rela->r_offset);
@ -963,6 +962,7 @@ static int soinfo_relocate_a(soinfo* si, Elf_Rela* rela, unsigned count, soinfo*
static_cast<size_t>(sym_addr), static_cast<size_t>(reloc), sym_name); static_cast<size_t>(sym_addr), static_cast<size_t>(reloc), sym_name);
*reinterpret_cast<Elf_Addr*>(reloc) = sym_addr + rela->r_addend - reloc; *reinterpret_cast<Elf_Addr*>(reloc) = sym_addr + rela->r_addend - reloc;
break; break;
#endif
default: default:
DL_ERR("unknown reloc type %d @ %p (%d)", type, rela, (int) (rela - start)); DL_ERR("unknown reloc type %d @ %p (%d)", type, rela, (int) (rela - start));
return -1; return -1;
@ -996,8 +996,7 @@ static int soinfo_relocate(soinfo* si, Elf_Rel* rel, unsigned count,
sym_name = (char *)(strtab + symtab[sym].st_name); sym_name = (char *)(strtab + symtab[sym].st_name);
s = soinfo_do_lookup(si, sym_name, &lsi, needed); s = soinfo_do_lookup(si, sym_name, &lsi, needed);
if (s == NULL) { if (s == NULL) {
/* We only allow an undefined symbol if this is a weak // We only allow an undefined symbol if this is a weak reference...
reference.. */
s = &symtab[sym]; s = &symtab[sym];
if (ELF_ST_BIND(s->st_info) != STB_WEAK) { if (ELF_ST_BIND(s->st_info) != STB_WEAK) {
DL_ERR("cannot locate symbol \"%s\" referenced by \"%s\"...", sym_name, si->name); DL_ERR("cannot locate symbol \"%s\" referenced by \"%s\"...", sym_name, si->name);
@ -1018,48 +1017,39 @@ static int soinfo_relocate(soinfo* si, Elf_Rel* rel, unsigned count,
*/ */
switch (type) { switch (type) {
#if defined(ANDROID_ARM_LINKER) #if defined(__arm__)
case R_ARM_JUMP_SLOT: case R_ARM_JUMP_SLOT:
case R_ARM_GLOB_DAT: case R_ARM_GLOB_DAT:
case R_ARM_ABS32: case R_ARM_ABS32:
case R_ARM_RELATIVE: /* Don't care. */ case R_ARM_RELATIVE: /* Don't care. */
#elif defined(ANDROID_X86_LINKER) // sym_addr was initialized to be zero above or relocation
// code below does not care about value of sym_addr.
// No need to do anything.
break;
#elif defined(__i386__)
case R_386_JMP_SLOT: case R_386_JMP_SLOT:
case R_386_GLOB_DAT: case R_386_GLOB_DAT:
case R_386_32: case R_386_32:
case R_386_RELATIVE: /* Don't care. */ case R_386_RELATIVE: /* Don't care. */
#endif /* ANDROID_*_LINKER */ // sym_addr was initialized to be zero above or relocation
/* sym_addr was initialized to be zero above or relocation // code below does not care about value of sym_addr.
code below does not care about value of sym_addr. // No need to do anything.
No need to do anything. */
break; break;
#if defined(ANDROID_X86_LINKER)
case R_386_PC32: case R_386_PC32:
sym_addr = reloc; sym_addr = reloc;
break; break;
#endif /* ANDROID_X86_LINKER */ #endif
#if defined(ANDROID_ARM_LINKER) #if defined(__arm__)
case R_ARM_COPY: case R_ARM_COPY:
/* Fall through. Can't really copy if weak symbol is // Fall through. Can't really copy if weak symbol is not found at run-time.
not found in run-time. */ #endif
#endif /* ANDROID_ARM_LINKER */
default: default:
DL_ERR("unknown weak reloc type %d @ %p (%d)", DL_ERR("unknown weak reloc type %d @ %p (%d)", type, rel, (int) (rel - start));
type, rel, (int) (rel - start));
return -1; return -1;
} }
} else { } else {
/* We got a definition. */ // We got a definition.
#if 0
if ((base == 0) && (si->base != 0)) {
/* linking from libraries to main image is bad */
DL_ERR("cannot locate \"%s\"...",
strtab + symtab[sym].st_name);
return -1;
}
#endif
sym_addr = static_cast<Elf_Addr>(s->st_value + lsi->load_bias); sym_addr = static_cast<Elf_Addr>(s->st_value + lsi->load_bias);
} }
count_relocation(kRelocSymbol); count_relocation(kRelocSymbol);
@ -1067,11 +1057,8 @@ static int soinfo_relocate(soinfo* si, Elf_Rel* rel, unsigned count,
s = NULL; s = NULL;
} }
/* TODO: This is ugly. Split up the relocations by arch into
* different files.
*/
switch (type) { switch (type) {
#if defined(ANDROID_ARM_LINKER) #if defined(__arm__)
case R_ARM_JUMP_SLOT: case R_ARM_JUMP_SLOT:
count_relocation(kRelocAbsolute); count_relocation(kRelocAbsolute);
MARK(rel->r_offset); MARK(rel->r_offset);
@ -1097,68 +1084,6 @@ static int soinfo_relocate(soinfo* si, Elf_Rel* rel, unsigned count,
reloc, sym_addr, rel->r_offset, sym_name); reloc, sym_addr, rel->r_offset, sym_name);
*reinterpret_cast<Elf_Addr*>(reloc) += sym_addr - rel->r_offset; *reinterpret_cast<Elf_Addr*>(reloc) += sym_addr - rel->r_offset;
break; break;
#elif defined(ANDROID_X86_LINKER)
case R_386_JMP_SLOT:
count_relocation(kRelocAbsolute);
MARK(rel->r_offset);
TRACE_TYPE(RELO, "RELO JMP_SLOT %08x <- %08x %s", reloc, sym_addr, sym_name);
*reinterpret_cast<Elf_Addr*>(reloc) = sym_addr;
break;
case R_386_GLOB_DAT:
count_relocation(kRelocAbsolute);
MARK(rel->r_offset);
TRACE_TYPE(RELO, "RELO GLOB_DAT %08x <- %08x %s", reloc, sym_addr, sym_name);
*reinterpret_cast<Elf_Addr*>(reloc) = sym_addr;
break;
#elif defined(ANDROID_MIPS_LINKER)
case R_MIPS_REL32:
count_relocation(kRelocAbsolute);
MARK(rel->r_offset);
TRACE_TYPE(RELO, "RELO REL32 %08x <- %08x %s",
reloc, sym_addr, (sym_name) ? sym_name : "*SECTIONHDR*");
if (s) {
*reinterpret_cast<Elf_Addr*>(reloc) += sym_addr;
} else {
*reinterpret_cast<Elf_Addr*>(reloc) += si->base;
}
break;
#endif /* ANDROID_*_LINKER */
#if defined(ANDROID_ARM_LINKER)
case R_ARM_RELATIVE:
#elif defined(ANDROID_X86_LINKER)
case R_386_RELATIVE:
#endif /* ANDROID_*_LINKER */
count_relocation(kRelocRelative);
MARK(rel->r_offset);
if (sym) {
DL_ERR("odd RELATIVE form...");
return -1;
}
TRACE_TYPE(RELO, "RELO RELATIVE %p <- +%p",
reinterpret_cast<void*>(reloc), reinterpret_cast<void*>(si->base));
*reinterpret_cast<Elf_Addr*>(reloc) += si->base;
break;
#if defined(ANDROID_X86_LINKER)
case R_386_32:
count_relocation(kRelocRelative);
MARK(rel->r_offset);
TRACE_TYPE(RELO, "RELO R_386_32 %08x <- +%08x %s", reloc, sym_addr, sym_name);
*reinterpret_cast<Elf_Addr*>(reloc) += sym_addr;
break;
case R_386_PC32:
count_relocation(kRelocRelative);
MARK(rel->r_offset);
TRACE_TYPE(RELO, "RELO R_386_PC32 %08x <- +%08x (%08x - %08x) %s",
reloc, (sym_addr - reloc), sym_addr, reloc, sym_name);
*reinterpret_cast<Elf_Addr*>(reloc) += (sym_addr - reloc);
break;
#endif /* ANDROID_X86_LINKER */
#ifdef ANDROID_ARM_LINKER
case R_ARM_COPY: case R_ARM_COPY:
if ((si->flags & FLAG_EXE) == 0) { if ((si->flags & FLAG_EXE) == 0) {
/* /*
@ -1201,11 +1126,64 @@ static int soinfo_relocate(soinfo* si, Elf_Rel* rel, unsigned count,
return -1; return -1;
} }
break; break;
#endif /* ANDROID_ARM_LINKER */ #elif defined(__i386__)
case R_386_JMP_SLOT:
count_relocation(kRelocAbsolute);
MARK(rel->r_offset);
TRACE_TYPE(RELO, "RELO JMP_SLOT %08x <- %08x %s", reloc, sym_addr, sym_name);
*reinterpret_cast<Elf_Addr*>(reloc) = sym_addr;
break;
case R_386_GLOB_DAT:
count_relocation(kRelocAbsolute);
MARK(rel->r_offset);
TRACE_TYPE(RELO, "RELO GLOB_DAT %08x <- %08x %s", reloc, sym_addr, sym_name);
*reinterpret_cast<Elf_Addr*>(reloc) = sym_addr;
break;
case R_386_32:
count_relocation(kRelocRelative);
MARK(rel->r_offset);
TRACE_TYPE(RELO, "RELO R_386_32 %08x <- +%08x %s", reloc, sym_addr, sym_name);
*reinterpret_cast<Elf_Addr*>(reloc) += sym_addr;
break;
case R_386_PC32:
count_relocation(kRelocRelative);
MARK(rel->r_offset);
TRACE_TYPE(RELO, "RELO R_386_PC32 %08x <- +%08x (%08x - %08x) %s",
reloc, (sym_addr - reloc), sym_addr, reloc, sym_name);
*reinterpret_cast<Elf_Addr*>(reloc) += (sym_addr - reloc);
break;
#elif defined(__mips__)
case R_MIPS_REL32:
count_relocation(kRelocAbsolute);
MARK(rel->r_offset);
TRACE_TYPE(RELO, "RELO REL32 %08x <- %08x %s",
reloc, sym_addr, (sym_name) ? sym_name : "*SECTIONHDR*");
if (s) {
*reinterpret_cast<Elf_Addr*>(reloc) += sym_addr;
} else {
*reinterpret_cast<Elf_Addr*>(reloc) += si->base;
}
break;
#endif
#if defined(__arm__)
case R_ARM_RELATIVE:
#elif defined(__i386__)
case R_386_RELATIVE:
#endif
count_relocation(kRelocRelative);
MARK(rel->r_offset);
if (sym) {
DL_ERR("odd RELATIVE form...");
return -1;
}
TRACE_TYPE(RELO, "RELO RELATIVE %p <- +%p",
reinterpret_cast<void*>(reloc), reinterpret_cast<void*>(si->base));
*reinterpret_cast<Elf_Addr*>(reloc) += si->base;
break;
default: default:
DL_ERR("unknown reloc type %d @ %p (%d)", DL_ERR("unknown reloc type %d @ %p (%d)", type, rel, (int) (rel - start));
type, rel, (int) (rel - start));
return -1; return -1;
} }
} }
@ -1213,7 +1191,7 @@ static int soinfo_relocate(soinfo* si, Elf_Rel* rel, unsigned count,
} }
#endif #endif
#ifdef ANDROID_MIPS_LINKER #if defined(__mips__)
static bool mips_relocate_got(soinfo* si, soinfo* needed[]) { static bool mips_relocate_got(soinfo* si, soinfo* needed[]) {
unsigned* got = si->plt_got; unsigned* got = si->plt_got;
if (got == NULL) { if (got == NULL) {
@ -1458,7 +1436,7 @@ static bool soinfo_link_image(soinfo* si) {
} }
} }
#ifdef ANDROID_ARM_LINKER #if defined(__arm__)
(void) phdr_table_get_arm_exidx(phdr, phnum, base, (void) phdr_table_get_arm_exidx(phdr, phnum, base,
&si->ARM_exidx, &si->ARM_exidx_count); &si->ARM_exidx, &si->ARM_exidx_count);
#endif #endif
@ -1481,7 +1459,7 @@ static bool soinfo_link_image(soinfo* si) {
case DT_SYMTAB: case DT_SYMTAB:
si->symtab = (Elf_Sym *) (base + d->d_un.d_ptr); si->symtab = (Elf_Sym *) (base + d->d_un.d_ptr);
break; break;
#if !defined(ANDROID_X86_64_LINKER) #if !defined(__LP64__)
case DT_PLTREL: case DT_PLTREL:
if (d->d_un.d_val != DT_REL) { if (d->d_un.d_val != DT_REL) {
DL_ERR("unsupported DT_RELA in \"%s\"", si->name); DL_ERR("unsupported DT_RELA in \"%s\"", si->name);
@ -1490,22 +1468,22 @@ static bool soinfo_link_image(soinfo* si) {
break; break;
#endif #endif
case DT_JMPREL: case DT_JMPREL:
#if defined(ANDROID_X86_64_LINKER) #if defined(USE_RELA)
si->plt_rela = (Elf_Rela*) (base + d->d_un.d_ptr); si->plt_rela = (Elf_Rela*) (base + d->d_un.d_ptr);
#else #else
si->plt_rel = (Elf_Rel*) (base + d->d_un.d_ptr); si->plt_rel = (Elf_Rel*) (base + d->d_un.d_ptr);
#endif #endif
break; break;
case DT_PLTRELSZ: case DT_PLTRELSZ:
#if defined(ANDROID_X86_64_LINKER) #if defined(USE_RELA)
si->plt_rela_count = d->d_un.d_val / sizeof(Elf_Rela); si->plt_rela_count = d->d_un.d_val / sizeof(Elf_Rela);
#else #else
si->plt_rel_count = d->d_un.d_val / sizeof(Elf_Rel); si->plt_rel_count = d->d_un.d_val / sizeof(Elf_Rel);
#endif #endif
break; break;
#if !defined(__LP64__)
case DT_PLTGOT: case DT_PLTGOT:
#if !defined(ANDROID_X86_64_LINKER) // Used by 32-bit MIPS.
/* Save this in case we decide to do lazy binding. We don't yet. */
si->plt_got = (unsigned *)(base + d->d_un.d_ptr); si->plt_got = (unsigned *)(base + d->d_un.d_ptr);
break; break;
#endif #endif
@ -1516,7 +1494,7 @@ static bool soinfo_link_image(soinfo* si) {
d->d_un.d_val = reinterpret_cast<uintptr_t>(&_r_debug); d->d_un.d_val = reinterpret_cast<uintptr_t>(&_r_debug);
} }
break; break;
#if defined(ANDROID_X86_64_LINKER) #if defined(USE_RELA)
case DT_RELA: case DT_RELA:
si->rela = (Elf_Rela*) (base + d->d_un.d_ptr); si->rela = (Elf_Rela*) (base + d->d_un.d_ptr);
break; break;
@ -1589,7 +1567,7 @@ static bool soinfo_link_image(soinfo* si) {
} }
break; break;
#endif #endif
#if defined(ANDROID_MIPS_LINKER) #if defined(__mips__)
case DT_STRSZ: case DT_STRSZ:
case DT_SYMENT: case DT_SYMENT:
case DT_RELENT: case DT_RELENT:
@ -1618,11 +1596,12 @@ static bool soinfo_link_image(soinfo* si) {
case DT_MIPS_GOTSYM: case DT_MIPS_GOTSYM:
si->mips_gotsym = d->d_un.d_val; si->mips_gotsym = d->d_un.d_val;
break; break;
#endif
default: default:
DEBUG("Unused DT entry: type 0x%08x arg 0x%08x", d->d_tag, d->d_un.d_val); DEBUG("Unused DT entry: type %p arg %p",
reinterpret_cast<void*>(d->d_tag), reinterpret_cast<void*>(d->d_un.d_val));
break; break;
#endif
} }
} }
@ -1697,7 +1676,7 @@ static bool soinfo_link_image(soinfo* si) {
} }
} }
#if defined(ANDROID_X86_64_LINKER) #if defined(USE_RELA)
if (si->plt_rela != NULL) { if (si->plt_rela != NULL) {
DEBUG("[ relocating %s plt ]\n", si->name ); DEBUG("[ relocating %s plt ]\n", si->name );
if (soinfo_relocate_a(si, si->plt_rela, si->plt_rela_count, needed)) { if (soinfo_relocate_a(si, si->plt_rela, si->plt_rela_count, needed)) {
@ -1725,7 +1704,7 @@ static bool soinfo_link_image(soinfo* si) {
} }
#endif #endif
#ifdef ANDROID_MIPS_LINKER #if defined(__mips__)
if (!mips_relocate_got(si, needed)) { if (!mips_relocate_got(si, needed)) {
return false; return false;
} }
@ -1761,7 +1740,7 @@ static bool soinfo_link_image(soinfo* si) {
* Also, it makes bionic more like glibc. * Also, it makes bionic more like glibc.
*/ */
static void add_vdso(KernelArgumentBlock& args UNUSED) { static void add_vdso(KernelArgumentBlock& args UNUSED) {
#ifdef AT_SYSINFO_EHDR #if defined(AT_SYSINFO_EHDR)
Elf_Ehdr* ehdr_vdso = reinterpret_cast<Elf_Ehdr*>(args.getauxval(AT_SYSINFO_EHDR)); Elf_Ehdr* ehdr_vdso = reinterpret_cast<Elf_Ehdr*>(args.getauxval(AT_SYSINFO_EHDR));
soinfo* si = soinfo_alloc("[vdso]"); soinfo* si = soinfo_alloc("[vdso]");
@ -1852,7 +1831,7 @@ static Elf_Addr __linker_init_post_relocation(KernelArgumentBlock& args, Elf_Add
*/ */
{ {
static soinfo linker_soinfo; static soinfo linker_soinfo;
#ifdef __LP64__ #if defined(__LP64__)
strlcpy(linker_soinfo.name, "/system/bin/linker64", sizeof(linker_soinfo.name)); strlcpy(linker_soinfo.name, "/system/bin/linker64", sizeof(linker_soinfo.name));
#else #else
strlcpy(linker_soinfo.name, "/system/bin/linker", sizeof(linker_soinfo.name)); strlcpy(linker_soinfo.name, "/system/bin/linker", sizeof(linker_soinfo.name));

23
linker/linker.h
View File

@ -97,6 +97,11 @@ struct r_debug {
typedef void (*linker_function_t)(); typedef void (*linker_function_t)();
// Android uses REL for 32-bit but only uses RELA for 64-bit.
#if defined(__LP64__)
#define USE_RELA 1
#endif
struct soinfo { struct soinfo {
public: public:
char name[SOINFO_NAME_LEN]; char name[SOINFO_NAME_LEN];
@ -128,15 +133,19 @@ struct soinfo {
unsigned* bucket; unsigned* bucket;
unsigned* chain; unsigned* chain;
#if defined(ANDROID_X86_64_LINKER) #if !defined(__LP64__)
Elf_Rela *plt_rela; // This is only used by 32-bit MIPS, but needs to be here for
// all 32-bit architectures to preserve binary compatibility.
unsigned* plt_got;
#endif
#if defined(USE_RELA)
Elf_Rela* plt_rela;
size_t plt_rela_count; size_t plt_rela_count;
Elf_Rela *rela; Elf_Rela* rela;
size_t rela_count; size_t rela_count;
#else #else
unsigned* plt_got;
Elf_Rel* plt_rel; Elf_Rel* plt_rel;
size_t plt_rel_count; size_t plt_rel_count;
@ -155,11 +164,11 @@ struct soinfo {
linker_function_t init_func; linker_function_t init_func;
linker_function_t fini_func; linker_function_t fini_func;
#if defined(ANDROID_ARM_LINKER) #if defined(__arm__)
// ARM EABI section used for stack unwinding. // ARM EABI section used for stack unwinding.
unsigned* ARM_exidx; unsigned* ARM_exidx;
size_t ARM_exidx_count; size_t ARM_exidx_count;
#elif defined(ANDROID_MIPS_LINKER) #elif defined(__mips__)
unsigned mips_symtabno; unsigned mips_symtabno;
unsigned mips_local_gotno; unsigned mips_local_gotno;
unsigned mips_gotsym; unsigned mips_gotsym;

18
linker/linker_phdr.cpp
View File

@ -202,13 +202,13 @@ bool ElfReader::VerifyElfHeader() {
} }
if (header_.e_machine != if (header_.e_machine !=
#ifdef ANDROID_ARM_LINKER #if defined(__arm__)
EM_ARM EM_ARM
#elif defined(ANDROID_MIPS_LINKER) #elif defined(__i386__)
EM_MIPS
#elif defined(ANDROID_X86_LINKER)
EM_386 EM_386
#elif defined(ANDROID_X86_64_LINKER) #elif defined(__mips__)
EM_MIPS
#elif defined(__x86_64__)
EM_X86_64 EM_X86_64
#endif #endif
) { ) {
@ -321,10 +321,6 @@ bool ElfReader::ReserveAddressSpace() {
return true; return true;
} }
// Map all loadable segments in process' address space.
// This assumes you already called phdr_table_reserve_memory to
// reserve the address space range for the library.
// TODO: assert assumption.
bool ElfReader::LoadSegments() { bool ElfReader::LoadSegments() {
for (size_t i = 0; i < phdr_num_; ++i) { for (size_t i = 0; i < phdr_num_; ++i) {
const Elf_Phdr* phdr = &phdr_table_[i]; const Elf_Phdr* phdr = &phdr_table_[i];
@ -513,7 +509,7 @@ int phdr_table_protect_gnu_relro(const Elf_Phdr* phdr_table, size_t phdr_count,
return _phdr_table_set_gnu_relro_prot(phdr_table, phdr_count, load_bias, PROT_READ); return _phdr_table_set_gnu_relro_prot(phdr_table, phdr_count, load_bias, PROT_READ);
} }
#ifdef ANDROID_ARM_LINKER #if defined(__arm__)
# ifndef PT_ARM_EXIDX # ifndef PT_ARM_EXIDX
# define PT_ARM_EXIDX 0x70000001 /* .ARM.exidx segment */ # define PT_ARM_EXIDX 0x70000001 /* .ARM.exidx segment */
@ -550,7 +546,7 @@ int phdr_table_get_arm_exidx(const Elf_Phdr* phdr_table, size_t phdr_count,
*arm_exidx_count = 0; *arm_exidx_count = 0;
return -1; return -1;
} }
#endif /* ANDROID_ARM_LINKER */ #endif
/* Return the address and size of the ELF file's .dynamic section in memory, /* Return the address and size of the ELF file's .dynamic section in memory,
* or NULL if missing. * or NULL if missing.

2
linker/linker_phdr.h
View File

@ -90,7 +90,7 @@ int phdr_table_unprotect_segments(const Elf_Phdr* phdr_table, size_t phdr_count,
int phdr_table_protect_gnu_relro(const Elf_Phdr* phdr_table, size_t phdr_count, Elf_Addr load_bias); int phdr_table_protect_gnu_relro(const Elf_Phdr* phdr_table, size_t phdr_count, Elf_Addr load_bias);
#ifdef ANDROID_ARM_LINKER #if defined(__arm__)
int phdr_table_get_arm_exidx(const Elf_Phdr* phdr_table, size_t phdr_count, Elf_Addr load_bias, int phdr_table_get_arm_exidx(const Elf_Phdr* phdr_table, size_t phdr_count, Elf_Addr load_bias,
Elf_Addr** arm_exidx, unsigned* arm_exidix_count); Elf_Addr** arm_exidx, unsigned* arm_exidix_count);
#endif #endif