Merge pull request #11456 from felipepiovezan/felipe/ptr_metadata_fixes_6_2_1

[lldb] Cherry-pick patches for pointer authentication support in 6.2.1

Author: JDevlieghere

lldb/include/lldb/Expression/IRMemoryMap.h

@@ -59,7 +59,7 @@ class IRMemoryMap {
                    size_t size, Status &error);
   void WriteScalarToMemory(lldb::addr_t process_address, Scalar &scalar,
                            size_t size, Status &error);
-  void WritePointerToMemory(lldb::addr_t process_address, lldb::addr_t address,
+  void WritePointerToMemory(lldb::addr_t process_address, lldb::addr_t pointer,
                             Status &error);
   void ReadMemory(uint8_t *bytes, lldb::addr_t process_address, size_t size,
                   Status &error);

lldb/include/lldb/Target/ABI.h

@@ -140,6 +140,10 @@ class ABI : public PluginInterface {
     return FixDataAddress(pc);
   }
 
+  virtual lldb::addr_t FixAnyAddressPreservingAuthentication(lldb::addr_t pc) {
+    return FixAnyAddress(pc);
+  }
+
   llvm::MCRegisterInfo &GetMCRegisterInfo() { return *m_mc_register_info_up; }
 
   virtual void

lldb/include/lldb/Target/Process.h

@@ -1463,6 +1463,11 @@ class Process : public std::enable_shared_from_this<Process>,
   /// platforms where there is a difference (only Arm Thumb at this time).
   lldb::addr_t FixAnyAddress(lldb::addr_t pc);
 
+  /// Strip pointer metadata except for the bits necessary to authenticate a
+  /// memory access. This is useful, for example, if `address` requires
+  /// authentication and it is going to be consumed in JITed code.
+  lldb::addr_t FixAnyAddressPreservingAuthentication(lldb::addr_t address);
+
   /// Get the Modification ID of the process.
   ///
   /// \return

lldb/include/lldb/Target/StackID.h

@@ -10,22 +10,27 @@
 #define LLDB_TARGET_STACKID_H
 
 #include "lldb/Core/AddressRange.h"
-#include "lldb/lldb-private.h"
 
 namespace lldb_private {
 
+class Process;
+
 class StackID {
 public:
-  // Constructors and Destructors
   StackID() = default;
 
-  StackID(const StackID &rhs) = default;
+  explicit StackID(lldb::addr_t pc, lldb::addr_t cfa,
+                   SymbolContextScope *symbol_scope, Process *process);
 
   ~StackID() = default;
 
   lldb::addr_t GetPC() const { return m_pc; }
 
-  lldb::addr_t GetCallFrameAddress() const { return m_cfa; }
+  lldb::addr_t GetCallFrameAddressWithMetadata() const {
+    return m_cfa_with_metadata;
+  }
+
+  lldb::addr_t GetCallFrameAddressWithoutMetadata() const { return m_cfa; }
 
   SymbolContextScope *GetSymbolContextScope() const { return m_symbol_scope; }
 
@@ -46,17 +51,6 @@ class StackID {
 
   void Dump(Stream *s);
 
-  // Operators
-  const StackID &operator=(const StackID &rhs) {
-    if (this != &rhs) {
-      m_pc = rhs.m_pc;
-      m_cfa = rhs.m_cfa;
-      m_cfa_on_stack = rhs.m_cfa_on_stack;
-      m_symbol_scope = rhs.m_symbol_scope;
-    }
-    return *this;
-  }
-
   /// Check if the CFA is on the stack, or elsewhere in the process, such as on
   /// the heap.
   bool IsCFAOnStack(Process &process) const;
@@ -68,34 +62,34 @@ class StackID {
 protected:
   friend class StackFrame;
 
-  explicit StackID(lldb::addr_t pc, lldb::addr_t cfa) : m_pc(pc), m_cfa(cfa) {}
-
-  void SetPC(lldb::addr_t pc) { m_pc = pc; }
-
-  void SetCFA(lldb::addr_t cfa) { m_cfa = cfa; }
-
-  lldb::addr_t m_pc =
-      LLDB_INVALID_ADDRESS; // The pc value for the function/symbol for this
-                            // frame. This will
-  // only get used if the symbol scope is nullptr (the code where we are
-  // stopped is not represented by any function or symbol in any shared
-  // library).
-  lldb::addr_t m_cfa =
-      LLDB_INVALID_ADDRESS; // The call frame address (stack pointer) value
-                            // at the beginning of the function that uniquely
-                            // identifies this frame (along with m_symbol_scope
-                            // below)
-  // True if the CFA is an address on the stack, false if it's an address
-  // elsewhere (ie heap).
+  void SetPC(lldb::addr_t pc, Process *process);
+  void SetCFA(lldb::addr_t cfa, Process *process);
+
+  /// The pc value for the function/symbol for this frame. This will only get
+  /// used if the symbol scope is nullptr (the code where we are stopped is not
+  /// represented by any function or symbol in any shared library).
+  lldb::addr_t m_pc = LLDB_INVALID_ADDRESS;
+
+  /// The call frame address (stack pointer) value at the beginning of the
+  /// function that uniquely identifies this frame (along with m_symbol_scope
+  /// below)
+  lldb::addr_t m_cfa = LLDB_INVALID_ADDRESS;
+
+  /// The cfa with metadata (i.e. prior to Process::FixAddress).
+  lldb::addr_t m_cfa_with_metadata = LLDB_INVALID_ADDRESS;
+
+  /// If nullptr, there is no block or symbol for this frame. If not nullptr,
+  /// this will either be the scope for the lexical block for the frame, or the
+  /// scope for the symbol. Symbol context scopes are always be unique pointers
+  /// since the are part of the Block and Symbol objects and can easily be used
+  /// to tell if a stack ID is the same as another.
+  SymbolContextScope *m_symbol_scope = nullptr;
+
+  // BEGIN SWIFT
+  /// True if the CFA is an address on the stack, false if it's an address
+  /// elsewhere (ie heap).
   mutable LazyBool m_cfa_on_stack = eLazyBoolCalculate;
-  SymbolContextScope *m_symbol_scope =
-      nullptr; // If nullptr, there is no block or symbol for this frame.
-               // If not nullptr, this will either be the scope for the
-               // lexical block for the frame, or the scope for the
-               // symbol. Symbol context scopes are always be unique
-               // pointers since the are part of the Block and Symbol
-               // objects and can easily be used to tell if a stack ID
-               // is the same as another.
+  // END SWIFT
 };
 
 bool operator==(const StackID &lhs, const StackID &rhs);

lldb/source/API/SBFrame.cpp

@@ -318,7 +318,7 @@ lldb::addr_t SBFrame::GetCFA() const {
 
   StackFrame *frame = exe_ctx.GetFramePtr();
   if (frame)
-    return frame->GetStackID().GetCallFrameAddress();
+    return frame->GetStackID().GetCallFrameAddressWithoutMetadata();
   return LLDB_INVALID_ADDRESS;
 }
 

lldb/source/Expression/DWARFExpression.cpp

@@ -1131,8 +1131,6 @@ llvm::Expected<Value> DWARFExpression::Evaluate(
             lldb::addr_t pointer_value =
                 process->ReadPointerFromMemory(pointer_addr, error);
             if (pointer_value != LLDB_INVALID_ADDRESS) {
-              if (ABISP abi_sp = process->GetABI())
-                pointer_value = abi_sp->FixCodeAddress(pointer_value);
               stack.back().GetScalar() = pointer_value;
               stack.back().ClearContext();
             } else {
@@ -2279,7 +2277,7 @@ llvm::Expected<Value> DWARFExpression::Evaluate(
         // Note that we don't have to parse FDEs because this DWARF expression
         // is commonly evaluated with a valid stack frame.
         StackID id = frame->GetStackID();
-        addr_t cfa = id.GetCallFrameAddress();
+        addr_t cfa = id.GetCallFrameAddressWithMetadata();
         if (cfa != LLDB_INVALID_ADDRESS) {
           stack.push_back(Scalar(cfa));
           stack.back().SetValueType(Value::ValueType::LoadAddress);

lldb/source/Expression/IRMemoryMap.cpp

@@ -635,10 +635,19 @@ void IRMemoryMap::WriteScalarToMemory(lldb::addr_t process_address,
 }
 
 void IRMemoryMap::WritePointerToMemory(lldb::addr_t process_address,
-                                       lldb::addr_t address, Status &error) {
+                                       lldb::addr_t pointer, Status &error) {
   error.Clear();
 
-  Scalar scalar(address);
+  /// Only ask the Process to fix `pointer` if the address belongs to the
+  /// process. An address belongs to the process if the Allocation policy is not
+  /// eAllocationPolicyHostOnly.
+  auto it = FindAllocation(pointer, 1);
+  if (it == m_allocations.end() ||
+      it->second.m_policy != AllocationPolicy::eAllocationPolicyHostOnly)
+    if (auto process_sp = GetProcessWP().lock())
+      pointer = process_sp->FixAnyAddressPreservingAuthentication(pointer);
+
+  Scalar scalar(pointer);
 
   WriteScalarToMemory(process_address, scalar, GetAddressByteSize(), error);
 }

lldb/source/Plugins/ABI/AArch64/ABIMacOSX_arm64.cpp

@@ -811,42 +811,48 @@ ValueObjectSP ABIMacOSX_arm64::GetReturnValueObjectImpl(
   return return_valobj_sp;
 }
 
-addr_t ABIMacOSX_arm64::FixCodeAddress(addr_t pc) {
-  addr_t pac_sign_extension = 0x0080000000000000ULL;
-  addr_t tbi_mask = 0xff80000000000000ULL;
-  addr_t mask = 0;
-
-  if (ProcessSP process_sp = GetProcessSP()) {
-    mask = process_sp->GetCodeAddressMask();
-    if (pc & pac_sign_extension) {
-      addr_t highmem_mask = process_sp->GetHighmemCodeAddressMask();
-      if (highmem_mask != LLDB_INVALID_ADDRESS_MASK)
-        mask = highmem_mask;
-    }
-  }
+constexpr addr_t tbi_mask = 0xff80000000000000ULL;
+constexpr addr_t pac_sign_extension = 0x0080000000000000ULL;
+
+/// Consults the process for its {code, data} address masks and applies it to
+/// `addr`.
+static addr_t DoFixAddr(addr_t addr, bool is_code, ProcessSP process_sp) {
+  if (!process_sp)
+    return addr;
+
+  addr_t mask = is_code ? process_sp->GetCodeAddressMask()
+                        : process_sp->GetDataAddressMask();
   if (mask == LLDB_INVALID_ADDRESS_MASK)
     mask = tbi_mask;
 
-  return (pc & pac_sign_extension) ? pc | mask : pc & (~mask);
+  if (addr & pac_sign_extension) {
+    addr_t highmem_mask = is_code ? process_sp->GetHighmemCodeAddressMask()
+                                  : process_sp->GetHighmemCodeAddressMask();
+    if (highmem_mask != LLDB_INVALID_ADDRESS_MASK)
+      return addr | highmem_mask;
+    return addr | mask;
+  }
+
+  return addr & (~mask);
 }
 
-addr_t ABIMacOSX_arm64::FixDataAddress(addr_t pc) {
-  addr_t pac_sign_extension = 0x0080000000000000ULL;
-  addr_t tbi_mask = 0xff80000000000000ULL;
-  addr_t mask = 0;
-
-  if (ProcessSP process_sp = GetProcessSP()) {
-    mask = process_sp->GetDataAddressMask();
-    if (pc & pac_sign_extension) {
-      addr_t highmem_mask = process_sp->GetHighmemDataAddressMask();
-      if (highmem_mask != LLDB_INVALID_ADDRESS_MASK)
-        mask = highmem_mask;
-    }
-  }
-  if (mask == LLDB_INVALID_ADDRESS_MASK)
-    mask = tbi_mask;
+addr_t ABIMacOSX_arm64::FixCodeAddress(addr_t pc) {
+  ProcessSP process_sp = GetProcessSP();
+  return DoFixAddr(pc, true /*is_code*/, GetProcessSP());
+}
+
+addr_t ABIMacOSX_arm64::FixDataAddress(addr_t addr) {
+  ProcessSP process_sp = GetProcessSP();
+  return DoFixAddr(addr, false /*is_code*/, GetProcessSP());
+}
+
+addr_t ABIMacOSX_arm64::FixAnyAddressPreservingAuthentication(addr_t addr) {
+  // Save the old MTE tag and restore it later.
+  constexpr addr_t mte_mask = 0x0f00000000000000ULL;
+  addr_t old_mte_tag = addr & mte_mask;
 
-  return (pc & pac_sign_extension) ? pc | mask : pc & (~mask);
+  addr_t fixed_addr = FixDataAddress(addr);
+  return old_mte_tag | (fixed_addr & (~mte_mask));
 }
 
 void ABIMacOSX_arm64::Initialize() {

lldb/source/Plugins/ABI/AArch64/ABIMacOSX_arm64.h

@@ -64,6 +64,7 @@ class ABIMacOSX_arm64 : public ABIAArch64 {
 
   lldb::addr_t FixCodeAddress(lldb::addr_t pc) override;
   lldb::addr_t FixDataAddress(lldb::addr_t pc) override;
+  lldb::addr_t FixAnyAddressPreservingAuthentication(lldb::addr_t pc) override;
 
   // Static Functions
 

lldb/source/Plugins/Language/Swift/SwiftFormatters.cpp

@@ -863,6 +863,8 @@ class TaskSyntheticFrontEnd : public SyntheticChildrenFrontEnd {
             m_ts->GetTypeFromMangledTypename(ConstString("$sSVD"));
 
         addr_t value = m_task_ptr;
+        if (auto process_sp = m_backend.GetProcessSP())
+          value = process_sp->FixDataAddress(value);
         DataExtractor data{reinterpret_cast<const void *>(&value),
                            sizeof(value), endian::InlHostByteOrder(),
                            sizeof(void *)};
@@ -903,7 +905,7 @@ class TaskSyntheticFrontEnd : public SyntheticChildrenFrontEnd {
             parent_addr = 0;
         }
 
-        addr_t value = parent_addr;
+        addr_t value = process_sp->FixDataAddress(parent_addr);
         DataExtractor data{reinterpret_cast<const void *>(&value),
                            sizeof(value), endian::InlHostByteOrder(),
                            sizeof(void *)};