ART: Do not relocate app program headers in patchoat.
Change the check whether to relocate program headers in
patchoat to simply look whether there is a PT_LOAD section
with p_vaddr == 0. If there is, don't relocate the headers,
it should be an app. Otherwise, it's a boot image and needs
to be relocated.
Add overflow checking to ElfFileImpl<>::GetLoadedSize().
Bug: 21047854
(cherry picked from commit 3fc9903407c6e89ffbbc92ded9e272d9de58e9b6)
Change-Id: Ib3e1295fc06993bcfbaadd8f253ee4f5498f52e9
diff --git a/compiler/elf_writer.cc b/compiler/elf_writer.cc
index 47402f3..f75638d 100644
--- a/compiler/elf_writer.cc
+++ b/compiler/elf_writer.cc
@@ -39,16 +39,17 @@
}
void ElfWriter::GetOatElfInformation(File* file,
- size_t& oat_loaded_size,
- size_t& oat_data_offset) {
+ size_t* oat_loaded_size,
+ size_t* oat_data_offset) {
std::string error_msg;
std::unique_ptr<ElfFile> elf_file(ElfFile::Open(file, false, false, &error_msg));
CHECK(elf_file.get() != nullptr) << error_msg;
- oat_loaded_size = elf_file->GetLoadedSize();
- CHECK_NE(0U, oat_loaded_size);
- oat_data_offset = GetOatDataAddress(elf_file.get());
- CHECK_NE(0U, oat_data_offset);
+ bool success = elf_file->GetLoadedSize(oat_loaded_size, &error_msg);
+ CHECK(success) << error_msg;
+ CHECK_NE(0U, *oat_loaded_size);
+ *oat_data_offset = GetOatDataAddress(elf_file.get());
+ CHECK_NE(0U, *oat_data_offset);
}
bool ElfWriter::Fixup(File* file, uintptr_t oat_data_begin) {
diff --git a/compiler/elf_writer.h b/compiler/elf_writer.h
index 033c1f8..8e13b51 100644
--- a/compiler/elf_writer.h
+++ b/compiler/elf_writer.h
@@ -38,8 +38,8 @@
// Looks up information about location of oat file in elf file container.
// Used for ImageWriter to perform memory layout.
static void GetOatElfInformation(File* file,
- size_t& oat_loaded_size,
- size_t& oat_data_offset);
+ size_t* oat_loaded_size,
+ size_t* oat_data_offset);
// Returns runtime oat_data runtime address for an opened ElfFile.
static uintptr_t GetOatDataAddress(ElfFile* elf_file);
diff --git a/compiler/image_writer.cc b/compiler/image_writer.cc
index 4dc7509..195949b 100644
--- a/compiler/image_writer.cc
+++ b/compiler/image_writer.cc
@@ -166,7 +166,7 @@
size_t oat_loaded_size = 0;
size_t oat_data_offset = 0;
- ElfWriter::GetOatElfInformation(oat_file.get(), oat_loaded_size, oat_data_offset);
+ ElfWriter::GetOatElfInformation(oat_file.get(), &oat_loaded_size, &oat_data_offset);
Thread::Current()->TransitionFromSuspendedToRunnable();
CreateHeader(oat_loaded_size, oat_data_offset);
diff --git a/patchoat/patchoat.cc b/patchoat/patchoat.cc
index 4dc0967..ef84a17 100644
--- a/patchoat/patchoat.cc
+++ b/patchoat/patchoat.cc
@@ -650,29 +650,34 @@
template <typename ElfFileImpl>
bool PatchOat::PatchElf(ElfFileImpl* oat_file) {
TimingLogger::ScopedTiming t("Fixup Elf Text Section", timings_);
+
+ // Fix up absolute references to locations within the boot image.
if (!oat_file->ApplyOatPatchesTo(".text", delta_)) {
return false;
}
+ // Update the OatHeader fields referencing the boot image.
if (!PatchOatHeader<ElfFileImpl>(oat_file)) {
return false;
}
- bool need_fixup = false;
+ bool need_boot_oat_fixup = true;
for (unsigned int i = 0; i < oat_file->GetProgramHeaderNum(); ++i) {
auto hdr = oat_file->GetProgramHeader(i);
- if ((hdr->p_vaddr != 0 && hdr->p_vaddr != hdr->p_offset) ||
- (hdr->p_paddr != 0 && hdr->p_paddr != hdr->p_offset)) {
- need_fixup = true;
+ if (hdr->p_type == PT_LOAD && hdr->p_vaddr == 0u) {
+ need_boot_oat_fixup = false;
break;
}
}
- if (!need_fixup) {
- // This was never passed through ElfFixup so all headers/symbols just have their offset as
- // their addr. Therefore we do not need to update these parts.
+ if (!need_boot_oat_fixup) {
+ // This is an app oat file that can be loaded at an arbitrary address in memory.
+ // Boot image references were patched above and there's nothing else to do.
return true;
}
+ // This is a boot oat file that's loaded at a particular address and we need
+ // to patch all absolute addresses, starting with ELF program headers.
+
t.NewTiming("Fixup Elf Headers");
// Fixup Phdr's
oat_file->FixupProgramHeaders(delta_);
diff --git a/runtime/elf_file.cc b/runtime/elf_file.cc
index e909e64..0c5210d 100644
--- a/runtime/elf_file.cc
+++ b/runtime/elf_file.cc
@@ -1080,9 +1080,9 @@
// Base on bionic phdr_table_get_load_size
template <typename ElfTypes>
-size_t ElfFileImpl<ElfTypes>::GetLoadedSize() const {
- Elf_Addr min_vaddr = 0xFFFFFFFFu;
- Elf_Addr max_vaddr = 0x00000000u;
+bool ElfFileImpl<ElfTypes>::GetLoadedSize(size_t* size, std::string* error_msg) const {
+ Elf_Addr min_vaddr = static_cast<Elf_Addr>(-1);
+ Elf_Addr max_vaddr = 0u;
for (Elf_Word i = 0; i < GetProgramHeaderNum(); i++) {
Elf_Phdr* program_header = GetProgramHeader(i);
if (program_header->p_type != PT_LOAD) {
@@ -1093,6 +1093,15 @@
min_vaddr = begin_vaddr;
}
Elf_Addr end_vaddr = program_header->p_vaddr + program_header->p_memsz;
+ if (UNLIKELY(begin_vaddr > end_vaddr)) {
+ std::ostringstream oss;
+ oss << "Program header #" << i << " has overflow in p_vaddr+p_memsz: 0x" << std::hex
+ << program_header->p_vaddr << "+0x" << program_header->p_memsz << "=0x" << end_vaddr
+ << " in ELF file \"" << file_->GetPath() << "\"";
+ *error_msg = oss.str();
+ *size = static_cast<size_t>(-1);
+ return false;
+ }
if (end_vaddr > max_vaddr) {
max_vaddr = end_vaddr;
}
@@ -1100,8 +1109,18 @@
min_vaddr = RoundDown(min_vaddr, kPageSize);
max_vaddr = RoundUp(max_vaddr, kPageSize);
CHECK_LT(min_vaddr, max_vaddr) << file_->GetPath();
- size_t loaded_size = max_vaddr - min_vaddr;
- return loaded_size;
+ Elf_Addr loaded_size = max_vaddr - min_vaddr;
+ // Check that the loaded_size fits in size_t.
+ if (UNLIKELY(loaded_size > std::numeric_limits<size_t>::max())) {
+ std::ostringstream oss;
+ oss << "Loaded size is 0x" << std::hex << loaded_size << " but maximum size_t is 0x"
+ << std::numeric_limits<size_t>::max() << " for ELF file \"" << file_->GetPath() << "\"";
+ *error_msg = oss.str();
+ *size = static_cast<size_t>(-1);
+ return false;
+ }
+ *size = loaded_size;
+ return true;
}
template <typename ElfTypes>
@@ -1164,9 +1183,14 @@
}
std::string reservation_name("ElfFile reservation for ");
reservation_name += file_->GetPath();
+ size_t loaded_size;
+ if (!GetLoadedSize(&loaded_size, error_msg)) {
+ DCHECK(!error_msg->empty());
+ return false;
+ }
std::unique_ptr<MemMap> reserve(MemMap::MapAnonymous(reservation_name.c_str(),
reserve_base_override,
- GetLoadedSize(), PROT_NONE, false, false,
+ loaded_size, PROT_NONE, false, false,
error_msg));
if (reserve.get() == nullptr) {
*error_msg = StringPrintf("Failed to allocate %s: %s",
@@ -1915,8 +1939,8 @@
DELEGATE_TO_IMPL(FindSymbolAddress, section_type, symbol_name, build_map);
}
-size_t ElfFile::GetLoadedSize() const {
- DELEGATE_TO_IMPL(GetLoadedSize);
+bool ElfFile::GetLoadedSize(size_t* size, std::string* error_msg) const {
+ DELEGATE_TO_IMPL(GetLoadedSize, size, error_msg);
}
bool ElfFile::Strip(File* file, std::string* error_msg) {
diff --git a/runtime/elf_file.h b/runtime/elf_file.h
index fe6896d..48cb4b8 100644
--- a/runtime/elf_file.h
+++ b/runtime/elf_file.h
@@ -66,7 +66,7 @@
const std::string& symbol_name,
bool build_map);
- size_t GetLoadedSize() const;
+ bool GetLoadedSize(size_t* size, std::string* error_msg) const;
// Strip an ELF file of unneeded debugging information.
// Returns true on success, false on failure.
diff --git a/runtime/elf_file_impl.h b/runtime/elf_file_impl.h
index 80950c6..3ad096f 100644
--- a/runtime/elf_file_impl.h
+++ b/runtime/elf_file_impl.h
@@ -106,8 +106,8 @@
Elf_Word GetRelaNum(Elf_Shdr&) const;
Elf_Rela& GetRela(Elf_Shdr&, Elf_Word) const;
- // Returns the expected size when the file is loaded at runtime
- size_t GetLoadedSize() const;
+ // Retrieves the expected size when the file is loaded at runtime. Returns true if successful.
+ bool GetLoadedSize(size_t* size, std::string* error_msg) const;
// Load segments into memory based on PT_LOAD program headers.
// executable is true at run time, false at compile time.
