Teach debuggerd to pass the secondary ring buffer to __scudo_get_error_info().

With this change we can report memory errors involving secondary
allocations. Update the existing crasher tests to also test
UAF/overflow/underflow on allocations with sizes sufficient to trigger
the secondary allocator.

Bug: 135772972
Change-Id: Ic8925c1f18621a8f272e26d5630e5d11d6d34d38

6 files changed, 29 insertions, 16 deletions

diff --git a/debuggerd/crash_dump.cpp b/debuggerd/crash_dump.cpp
index 68a43cffb..c8612bfeb 100644
--- a/debuggerd/crash_dump.cpp
+++ b/debuggerd/crash_dump.cpp
@@ -303,6 +303,7 @@ static void ReadCrashInfo(unique_fd& fd, siginfo_t* siginfo,
       process_info->gwp_asan_metadata = crash_info->data.d.gwp_asan_metadata;
       process_info->scudo_stack_depot = crash_info->data.d.scudo_stack_depot;
       process_info->scudo_region_info = crash_info->data.d.scudo_region_info;
+      process_info->scudo_ring_buffer = crash_info->data.d.scudo_ring_buffer;
       FALLTHROUGH_INTENDED;
     case 1:
     case 2:
diff --git a/debuggerd/debuggerd_test.cpp b/debuggerd/debuggerd_test.cpp
index b9d66063e..abce0569f 100644
--- a/debuggerd/debuggerd_test.cpp
+++ b/debuggerd/debuggerd_test.cpp
@@ -391,7 +391,11 @@ static void SetTagCheckingLevelSync() {
 }
 #endif
 
-TEST_F(CrasherTest, mte_uaf) {
+struct SizeParamCrasherTest : CrasherTest, testing::WithParamInterface<size_t> {};
+
+INSTANTIATE_TEST_SUITE_P(Sizes, SizeParamCrasherTest, testing::Values(16, 131072));
+
+TEST_P(SizeParamCrasherTest, mte_uaf) {
 #if defined(__aarch64__)
   if (!mte_supported()) {
     GTEST_SKIP() << "Requires MTE";
@@ -399,9 +403,9 @@ TEST_F(CrasherTest, mte_uaf) {
 
   int intercept_result;
   unique_fd output_fd;
-  StartProcess([]() {
+  StartProcess([&]() {
     SetTagCheckingLevelSync();
-    volatile int* p = (volatile int*)malloc(16);
+    volatile int* p = (volatile int*)malloc(GetParam());
     free((void *)p);
     p[0] = 42;
   });
@@ -416,8 +420,9 @@ TEST_F(CrasherTest, mte_uaf) {
   std::string result;
   ConsumeFd(std::move(output_fd), &result);
 
-  ASSERT_MATCH(result, R"(signal 11 \(SIGSEGV\), code 9 \(SEGV_MTESERR\))");
-  ASSERT_MATCH(result, R"(Cause: \[MTE\]: Use After Free, 0 bytes into a 16-byte allocation.*
+  ASSERT_MATCH(result, R"(signal 11 \(SIGSEGV\))");
+  ASSERT_MATCH(result, R"(Cause: \[MTE\]: Use After Free, 0 bytes into a )" +
+                           std::to_string(GetParam()) + R"(-byte allocation.*
 
 allocated by thread .*
       #00 pc)");
@@ -428,7 +433,7 @@ allocated by thread .*
 #endif
 }
 
-TEST_F(CrasherTest, mte_overflow) {
+TEST_P(SizeParamCrasherTest, mte_overflow) {
 #if defined(__aarch64__)
   if (!mte_supported()) {
     GTEST_SKIP() << "Requires MTE";
@@ -436,10 +441,10 @@ TEST_F(CrasherTest, mte_overflow) {
 
   int intercept_result;
   unique_fd output_fd;
-  StartProcess([]() {
+  StartProcess([&]() {
     SetTagCheckingLevelSync();
-    volatile int* p = (volatile int*)malloc(16);
-    p[4] = 42;
+    volatile char* p = (volatile char*)malloc(GetParam());
+    p[GetParam()] = 42;
   });
 
   StartIntercept(&output_fd);
@@ -453,7 +458,8 @@ TEST_F(CrasherTest, mte_overflow) {
   ConsumeFd(std::move(output_fd), &result);
 
   ASSERT_MATCH(result, R"(signal 11 \(SIGSEGV\))");
-  ASSERT_MATCH(result, R"(Cause: \[MTE\]: Buffer Overflow, 0 bytes right of a 16-byte allocation.*
+  ASSERT_MATCH(result, R"(Cause: \[MTE\]: Buffer Overflow, 0 bytes right of a )" +
+                           std::to_string(GetParam()) + R"(-byte allocation.*
 
 allocated by thread .*
       #00 pc)");
@@ -462,7 +468,7 @@ allocated by thread .*
 #endif
 }
 
-TEST_F(CrasherTest, mte_underflow) {
+TEST_P(SizeParamCrasherTest, mte_underflow) {
 #if defined(__aarch64__)
   if (!mte_supported()) {
     GTEST_SKIP() << "Requires MTE";
@@ -470,9 +476,9 @@ TEST_F(CrasherTest, mte_underflow) {
 
   int intercept_result;
   unique_fd output_fd;
-  StartProcess([]() {
+  StartProcess([&]() {
     SetTagCheckingLevelSync();
-    volatile int* p = (volatile int*)malloc(16);
+    volatile int* p = (volatile int*)malloc(GetParam());
     p[-1] = 42;
   });
 
@@ -487,7 +493,8 @@ TEST_F(CrasherTest, mte_underflow) {
   ConsumeFd(std::move(output_fd), &result);
 
   ASSERT_MATCH(result, R"(signal 11 \(SIGSEGV\), code 9 \(SEGV_MTESERR\))");
-  ASSERT_MATCH(result, R"(Cause: \[MTE\]: Buffer Underflow, 4 bytes left of a 16-byte allocation.*
+  ASSERT_MATCH(result, R"(Cause: \[MTE\]: Buffer Underflow, 4 bytes left of a )" +
+                           std::to_string(GetParam()) + R"(-byte allocation.*
 
 allocated by thread .*
       #00 pc)");
diff --git a/debuggerd/include/debuggerd/handler.h b/debuggerd/include/debuggerd/handler.h
index 254ed4f7b..bc08327a1 100644
--- a/debuggerd/include/debuggerd/handler.h
+++ b/debuggerd/include/debuggerd/handler.h
@@ -42,6 +42,7 @@ struct debugger_process_info {
   const gwp_asan::AllocationMetadata* gwp_asan_metadata;
   const char* scudo_stack_depot;
   const char* scudo_region_info;
+  const char* scudo_ring_buffer;
 };
 
 // These callbacks are called in a signal handler, and thus must be async signal safe.
diff --git a/debuggerd/libdebuggerd/include/libdebuggerd/types.h b/debuggerd/libdebuggerd/include/libdebuggerd/types.h
index d5b07355f..dcb52f92a 100644
--- a/debuggerd/libdebuggerd/include/libdebuggerd/types.h
+++ b/debuggerd/libdebuggerd/include/libdebuggerd/types.h
@@ -46,6 +46,7 @@ struct ProcessInfo {
   uintptr_t gwp_asan_metadata = 0;
   uintptr_t scudo_stack_depot = 0;
   uintptr_t scudo_region_info = 0;
+  uintptr_t scudo_ring_buffer = 0;
 
   bool has_fault_address = false;
   uintptr_t untagged_fault_address = 0;
diff --git a/debuggerd/libdebuggerd/scudo.cpp b/debuggerd/libdebuggerd/scudo.cpp
index 141c3bd18..1c3437fde 100644
--- a/debuggerd/libdebuggerd/scudo.cpp
+++ b/debuggerd/libdebuggerd/scudo.cpp
@@ -43,6 +43,8 @@ ScudoCrashData::ScudoCrashData(unwindstack::Memory* process_memory,
                                        __scudo_get_stack_depot_size());
   auto region_info = AllocAndReadFully(process_memory, process_info.scudo_region_info,
                                        __scudo_get_region_info_size());
+  auto ring_buffer = AllocAndReadFully(process_memory, process_info.scudo_ring_buffer,
+                                       __scudo_get_ring_buffer_size());
 
   untagged_fault_addr_ = process_info.untagged_fault_address;
   uintptr_t fault_page = untagged_fault_addr_ & ~(PAGE_SIZE - 1);
@@ -68,8 +70,8 @@ ScudoCrashData::ScudoCrashData(unwindstack::Memory* process_memory,
   }
 
   __scudo_get_error_info(&error_info_, process_info.maybe_tagged_fault_address, stack_depot.get(),
-                         region_info.get(), memory.get(), memory_tags.get(), memory_begin,
-                         memory_end - memory_begin);
+                         region_info.get(), ring_buffer.get(), memory.get(), memory_tags.get(),
+                         memory_begin, memory_end - memory_begin);
 }
 
 bool ScudoCrashData::CrashIsMine() const {
diff --git a/debuggerd/protocol.h b/debuggerd/protocol.h
index 53a76ea71..f33b2f0c9 100644
--- a/debuggerd/protocol.h
+++ b/debuggerd/protocol.h
@@ -97,6 +97,7 @@ struct __attribute__((__packed__)) CrashInfoDataDynamic : public CrashInfoDataSt
   uintptr_t gwp_asan_metadata;
   uintptr_t scudo_stack_depot;
   uintptr_t scudo_region_info;
+  uintptr_t scudo_ring_buffer;
 };
 
 struct __attribute__((__packed__)) CrashInfo {