Add support for packed relocations.
Change-Id: I796a4ce86d3fccb8361c19889419c96147ee3c9f
diff --git a/linker/linker.cpp b/linker/linker.cpp
index ae9df52..87fce95 100644
--- a/linker/linker.cpp
+++ b/linker/linker.cpp
@@ -53,6 +53,7 @@
#include "linker_allocator.h"
#include "linker_debug.h"
#include "linker_environ.h"
+#include "linker_leb128.h"
#include "linker_phdr.h"
#include "linker_relocs.h"
#include "linker_reloc_iterators.h"
@@ -1302,6 +1303,10 @@
bool soinfo::relocate(ElfRelIteratorT&& rel_iterator, const soinfo_list_t& global_group, const soinfo_list_t& local_group) {
for (size_t idx = 0; rel_iterator.has_next(); ++idx) {
const auto rel = rel_iterator.next();
+ if (rel == nullptr) {
+ return false;
+ }
+
ElfW(Word) type = ELFW(R_TYPE)(rel->r_info);
ElfW(Word) sym = ELFW(R_SYM)(rel->r_info);
@@ -1407,16 +1412,16 @@
MARK(rel->r_offset);
TRACE_TYPE(RELO, "RELO RELATIVE %16p <- %16p\n",
reinterpret_cast<void*>(reloc),
- reinterpret_cast<void*>(base + addend));
- *reinterpret_cast<ElfW(Addr)*>(reloc) = (base + addend);
+ reinterpret_cast<void*>(load_bias + addend));
+ *reinterpret_cast<ElfW(Addr)*>(reloc) = (load_bias + addend);
break;
case R_GENERIC_IRELATIVE:
count_relocation(kRelocRelative);
MARK(rel->r_offset);
TRACE_TYPE(RELO, "RELO IRELATIVE %16p <- %16p\n",
reinterpret_cast<void*>(reloc),
- reinterpret_cast<void*>(base + addend));
- *reinterpret_cast<ElfW(Addr)*>(reloc) = call_ifunc_resolver(base + addend);
+ reinterpret_cast<void*>(load_bias + addend));
+ *reinterpret_cast<ElfW(Addr)*>(reloc) = call_ifunc_resolver(load_bias + addend);
break;
#if defined(__aarch64__)
@@ -2053,6 +2058,22 @@
rela_count_ = d->d_un.d_val / sizeof(ElfW(Rela));
break;
+ case DT_ANDROID_RELA:
+ android_relocs_ = reinterpret_cast<uint8_t*>(load_bias + d->d_un.d_ptr);
+ break;
+
+ case DT_ANDROID_RELASZ:
+ android_relocs_size_ = d->d_un.d_val;
+ break;
+
+ case DT_ANDROID_REL:
+ DL_ERR("unsupported DT_ANDROID_REL in \"%s\"", name);
+ return false;
+
+ case DT_ANDROID_RELSZ:
+ DL_ERR("unsupported DT_ANDROID_RELSZ in \"%s\"", name);
+ return false;
+
case DT_RELAENT:
if (d->d_un.d_val != sizeof(ElfW(Rela))) {
DL_ERR("invalid DT_RELAENT: %zd", static_cast<size_t>(d->d_un.d_val));
@@ -2071,6 +2092,7 @@
case DT_RELSZ:
DL_ERR("unsupported DT_RELSZ in \"%s\"", name);
return false;
+
#else
case DT_REL:
rel_ = reinterpret_cast<ElfW(Rel)*>(load_bias + d->d_un.d_ptr);
@@ -2087,6 +2109,22 @@
}
break;
+ case DT_ANDROID_REL:
+ android_relocs_ = reinterpret_cast<uint8_t*>(load_bias + d->d_un.d_ptr);
+ break;
+
+ case DT_ANDROID_RELSZ:
+ android_relocs_size_ = d->d_un.d_val;
+ break;
+
+ case DT_ANDROID_RELA:
+ DL_ERR("unsupported DT_ANDROID_RELA in \"%s\"", name);
+ return false;
+
+ case DT_ANDROID_RELASZ:
+ DL_ERR("unsupported DT_ANDROID_RELASZ in \"%s\"", name);
+ return false;
+
// "Indicates that all RELATIVE relocations have been concatenated together,
// and specifies the RELATIVE relocation count."
//
@@ -2094,9 +2132,15 @@
// Not currently used by bionic linker - ignored.
case DT_RELCOUNT:
break;
+
case DT_RELA:
DL_ERR("unsupported DT_RELA in \"%s\"", name);
return false;
+
+ case DT_RELASZ:
+ DL_ERR("unsupported DT_RELASZ in \"%s\"", name);
+ return false;
+
#endif
case DT_INIT:
init_func_ = reinterpret_cast<linker_function_t>(load_bias + d->d_un.d_ptr);
@@ -2251,7 +2295,8 @@
return true;
}
-bool soinfo::link_image(const soinfo_list_t& global_group, const soinfo_list_t& local_group, const android_dlextinfo* extinfo) {
+bool soinfo::link_image(const soinfo_list_t& global_group, const soinfo_list_t& local_group,
+ const android_dlextinfo* extinfo) {
local_group_root_ = local_group.front();
if (local_group_root_ == nullptr) {
@@ -2272,6 +2317,40 @@
}
#endif
+ if (android_relocs_ != nullptr) {
+ // check signature
+ if (android_relocs_size_ > 3 &&
+ android_relocs_[0] == 'A' &&
+ android_relocs_[1] == 'P' &&
+ (android_relocs_[2] == 'U' || android_relocs_[2] == 'S') &&
+ android_relocs_[3] == '2') {
+ DEBUG("[ android relocating %s ]", name);
+
+ bool relocated = false;
+ const uint8_t* packed_relocs = android_relocs_ + 4;
+ const size_t packed_relocs_size = android_relocs_size_ - 4;
+
+ if (android_relocs_[2] == 'U') {
+ relocated = relocate(
+ packed_reloc_iterator<leb128_decoder>(
+ leb128_decoder(packed_relocs, packed_relocs_size)),
+ global_group, local_group);
+ } else { // android_relocs_[2] == 'S'
+ relocated = relocate(
+ packed_reloc_iterator<sleb128_decoder>(
+ sleb128_decoder(packed_relocs, packed_relocs_size)),
+ global_group, local_group);
+ }
+
+ if (!relocated) {
+ return false;
+ }
+ } else {
+ DL_ERR("bad android relocation header.");
+ return false;
+ }
+ }
+
#if defined(USE_RELA)
if (rela_ != nullptr) {
DEBUG("[ relocating %s ]", name);