Fix handling of globals for new linker.oreo-mr1-1.2-iot-release

The new linker base map is read-only, but the global handling code
for jit and dex information assumed the base map was a read-execute
one. Relax that requirement to search read-only maps.

Adjust the unit tests for this case.

Bug: 117293117
Test: Passes unit tests.
Test: Passes art cfi tests with and without llvm linker.
Change-Id: I31a765d51847d0b8d778ace9cbaa29f42073f4d9

4 files changed, 16 insertions, 17 deletions

diff --git a/libunwindstack/DexFiles.cpp b/libunwindstack/DexFiles.cpp
index 430f6c5..17e2526 100644
--- a/libunwindstack/DexFiles.cpp
+++ b/libunwindstack/DexFiles.cpp
@@ -126,7 +126,7 @@ void DexFiles::Init(Maps* maps) {
 
   const std::string dex_debug_name("__dex_debug_descriptor");
   for (MapInfo* info : *maps) {
-    if (!(info->flags & PROT_EXEC) || !(info->flags & PROT_READ) || info->offset != 0) {
+    if (!(info->flags & PROT_READ) || info->offset != 0) {
       continue;
     }
 
diff --git a/libunwindstack/JitDebug.cpp b/libunwindstack/JitDebug.cpp
index 0c319ec..821aacf 100644
--- a/libunwindstack/JitDebug.cpp
+++ b/libunwindstack/JitDebug.cpp
@@ -174,7 +174,7 @@ void JitDebug::Init(Maps* maps) {
 
   const std::string descriptor_name("__jit_debug_descriptor");
   for (MapInfo* info : *maps) {
-    if (!(info->flags & PROT_EXEC) || !(info->flags & PROT_READ) || info->offset != 0) {
+    if (!(info->flags & PROT_READ) || info->offset != 0) {
       continue;
     }
 
@@ -194,10 +194,9 @@ void JitDebug::Init(Maps* maps) {
 
     Elf* elf = info->GetElf(memory_, true);
     uint64_t descriptor_addr;
-    if (elf->GetGlobalVariable(descriptor_name, &descriptor_addr)) {
-      // Search for the first non-zero entry.
-      descriptor_addr += info->start;
-      entry_addr_ = (this->*read_descriptor_func_)(descriptor_addr);
+    // Find first non-empty entry (libart might be loaded multiple times).
+    if (elf->GetGlobalVariable(descriptor_name, &descriptor_addr) && descriptor_addr != 0) {
+      entry_addr_ = (this->*read_descriptor_func_)(descriptor_addr + info->start);
       if (entry_addr_ != 0) {
         break;
       }
diff --git a/libunwindstack/tests/DexFilesTest.cpp b/libunwindstack/tests/DexFilesTest.cpp
index d029bb0..c6d7f33 100644
--- a/libunwindstack/tests/DexFilesTest.cpp
+++ b/libunwindstack/tests/DexFilesTest.cpp
@@ -46,17 +46,17 @@ class DexFilesTest : public ::testing::Test {
     maps_.reset(
         new BufferMaps("1000-4000 ---s 00000000 00:00 0\n"
                        "4000-6000 r--s 00000000 00:00 0\n"
-                       "6000-8000 -w-s 00000000 00:00 0\n"
-                       "a000-c000 r-xp 00000000 00:00 0\n"
-                       "c000-f000 rwxp 00000000 00:00 0\n"
-                       "f000-11000 r-xp 00000000 00:00 0\n"
+                       "6000-8000 -wxs 00000000 00:00 0\n"
+                       "a000-c000 r--p 00000000 00:00 0\n"
+                       "c000-f000 rw-p 00000000 00:00 0\n"
+                       "f000-11000 r--p 00000000 00:00 0\n"
                        "100000-110000 rw-p 0000000 00:00 0\n"
                        "200000-210000 rw-p 0000000 00:00 0\n"
                        "300000-400000 rw-p 0000000 00:00 0\n"));
     ASSERT_TRUE(maps_->Parse());
 
-    // Global variable in a section that is not readable/executable.
-    MapInfo* map_info = maps_->Get(kMapGlobalNonReadableExectable);
+    // Global variable in a section that is not readable.
+    MapInfo* map_info = maps_->Get(kMapGlobalNonReadable);
     ASSERT_TRUE(map_info != nullptr);
     MemoryFake* memory = new MemoryFake;
     ElfFake* elf = new ElfFake(memory);
@@ -95,7 +95,7 @@ class DexFilesTest : public ::testing::Test {
   void WriteEntry64(uint64_t entry_addr, uint64_t next, uint64_t prev, uint64_t dex_file);
   void WriteDex(uint64_t dex_file);
 
-  static constexpr size_t kMapGlobalNonReadableExectable = 3;
+  static constexpr size_t kMapGlobalNonReadable = 2;
   static constexpr size_t kMapGlobalSetToZero = 4;
   static constexpr size_t kMapGlobal = 5;
   static constexpr size_t kMapDexFileEntries = 7;
diff --git a/libunwindstack/tests/JitDebugTest.cpp b/libunwindstack/tests/JitDebugTest.cpp
index c1c45f8..66f0859 100644
--- a/libunwindstack/tests/JitDebugTest.cpp
+++ b/libunwindstack/tests/JitDebugTest.cpp
@@ -45,11 +45,11 @@ class JitDebugTest : public ::testing::Test {
     maps_.reset(
         new BufferMaps("1000-4000 ---s 00000000 00:00 0\n"
                        "4000-6000 r--s 00000000 00:00 0\n"
-                       "6000-8000 -w-s 00000000 00:00 0\n"
+                       "6000-8000 -wxs 00000000 00:00 0\n"
                        "a000-c000 --xp 00000000 00:00 0\n"
-                       "c000-f000 rwxp 00000000 00:00 0\n"
-                       "f000-11000 r-xp 00000000 00:00 0\n"
-                       "12000-14000 r-xp 00000000 00:00 0\n"
+                       "c000-f000 rw-p 00000000 00:00 0\n"
+                       "f000-11000 r--p 00000000 00:00 0\n"
+                       "12000-14000 r--p 00000000 00:00 0\n"
                        "100000-110000 rw-p 0000000 00:00 0\n"
                        "200000-210000 rw-p 0000000 00:00 0\n"));
     ASSERT_TRUE(maps_->Parse());