[lldb][ClangModulesDeclVendor] Fix use-after-free of diagnostics stream #167724
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This got exposed by `09262656f32ab3f2e1d82e5342ba37eecac52522`. The underlying stream of `m_os` is referenced by `TextDiagnostic` member of `TextDiagnosticPrinter`. It got turned into a `llvm::formatted_raw_ostream` in the commit above. When `~TextDiagnosticPrinter` (and thus `~TextDiagnostic`) is invoked, we now call `~formatted_raw_ostream`, which tries to access the underlying stream. But `m_os` was already deleted because it is earlier in the order of destruction in `TextDiagnosticPrinter`. Move the `m_os` member before the `TextDiagnosticPrinter` to avoid a use-after-free. The ASAN macOS bot is currently failing with this: ``` 08:15:39 ================================================================= 08:15:39 ==61103==ERROR: AddressSanitizer: heap-use-after-free on address 0x60600012cf40 at pc 0x00012140d304 bp 0x00016eecc850 sp 0x00016eecc848 08:15:39 READ of size 8 at 0x60600012cf40 thread T0 08:15:39 #0 0x00012140d300 in llvm::formatted_raw_ostream::releaseStream() FormattedStream.h:205 08:15:39 llvm#1 0x00012140d3a4 in llvm::formatted_raw_ostream::~formatted_raw_ostream() FormattedStream.h:145 08:15:39 llvm#2 0x00012604abf8 in clang::TextDiagnostic::~TextDiagnostic() TextDiagnostic.cpp:721 08:15:39 llvm#3 0x00012605dc80 in clang::TextDiagnosticPrinter::~TextDiagnosticPrinter() TextDiagnosticPrinter.cpp:30 08:15:39 llvm#4 0x00012605dd5c in clang::TextDiagnosticPrinter::~TextDiagnosticPrinter() TextDiagnosticPrinter.cpp:27 08:15:39 llvm#5 0x0001231fb210 in (anonymous namespace)::StoringDiagnosticConsumer::~StoringDiagnosticConsumer() ClangModulesDeclVendor.cpp:47 08:15:39 llvm#6 0x0001231fb3bc in (anonymous namespace)::StoringDiagnosticConsumer::~StoringDiagnosticConsumer() ClangModulesDeclVendor.cpp:47 08:15:39 llvm#7 0x000129aa9d70 in clang::DiagnosticsEngine::~DiagnosticsEngine() Diagnostic.cpp:91 08:15:39 llvm#8 0x0001230436b8 in llvm::RefCountedBase<clang::DiagnosticsEngine>::Release() const IntrusiveRefCntPtr.h:103 08:15:39 llvm#9 0x0001231fe6c8 in (anonymous namespace)::ClangModulesDeclVendorImpl::~ClangModulesDeclVendorImpl() ClangModulesDeclVendor.cpp:93 08:15:39 llvm#10 0x0001231fe858 in (anonymous namespace)::ClangModulesDeclVendorImpl::~ClangModulesDeclVendorImpl() ClangModulesDeclVendor.cpp:93 ... 08:15:39 08:15:39 0x60600012cf40 is located 32 bytes inside of 56-byte region [0x60600012cf20,0x60600012cf58) 08:15:39 freed by thread T0 here: 08:15:39 #0 0x0001018abb88 in _ZdlPv+0x74 (libclang_rt.asan_osx_dynamic.dylib:arm64e+0x4bb88) 08:15:39 llvm#1 0x0001231fb1c0 in (anonymous namespace)::StoringDiagnosticConsumer::~StoringDiagnosticConsumer() ClangModulesDeclVendor.cpp:47 08:15:39 llvm#2 0x0001231fb3bc in (anonymous namespace)::StoringDiagnosticConsumer::~StoringDiagnosticConsumer() ClangModulesDeclVendor.cpp:47 08:15:39 llvm#3 0x000129aa9d70 in clang::DiagnosticsEngine::~DiagnosticsEngine() Diagnostic.cpp:91 08:15:39 llvm#4 0x0001230436b8 in llvm::RefCountedBase<clang::DiagnosticsEngine>::Release() const IntrusiveRefCntPtr.h:103 08:15:39 llvm#5 0x0001231fe6c8 in (anonymous namespace)::ClangModulesDeclVendorImpl::~ClangModulesDeclVendorImpl() ClangModulesDeclVendor.cpp:93 08:15:39 llvm#6 0x0001231fe858 in (anonymous namespace)::ClangModulesDeclVendorImpl::~ClangModulesDeclVendorImpl() ClangModulesDeclVendor.cpp:93 ... 08:15:39 08:15:39 previously allocated by thread T0 here: 08:15:39 #0 0x0001018ab760 in _Znwm+0x74 (libclang_rt.asan_osx_dynamic.dylib:arm64e+0x4b760) 08:15:39 llvm#1 0x0001231f8dec in lldb_private::ClangModulesDeclVendor::Create(lldb_private::Target&) ClangModulesDeclVendor.cpp:732 08:15:39 llvm#2 0x00012320af58 in lldb_private::ClangPersistentVariables::GetClangModulesDeclVendor() ClangPersistentVariables.cpp:124 08:15:39 llvm#3 0x0001232111f0 in lldb_private::ClangUserExpression::PrepareForParsing(lldb_private::DiagnosticManager&, lldb_private::ExecutionContext&, bool) ClangUserExpression.cpp:536 08:15:39 llvm#4 0x000123213790 in lldb_private::ClangUserExpression::Parse(lldb_private::DiagnosticManager&, lldb_private::ExecutionContext&, lldb_private::ExecutionPolicy, bool, bool) ClangUserExpression.cpp:647 08:15:39 llvm#5 0x00012032b258 in lldb_private::UserExpression::Evaluate(lldb_private::ExecutionContext&, lldb_private::EvaluateExpressionOptions const&, llvm::StringRef, llvm::StringRef, std::__1::shared_ptr<lldb_private::ValueObject>&, std::__1::basic_string<char, std::__1::char_traits<char>, std::__1::allocator<char>>*, lldb_private::ValueObject*) UserExpression.cpp:280 08:15:39 llvm#6 0x000120724010 in lldb_private::Target::EvaluateExpression(llvm::StringRef, lldb_private::ExecutionContextScope*, std::__1::shared_ptr<lldb_private::ValueObject>&, lldb_private::EvaluateExpressionOptions const&, std::__1::basic_string<char, std::__1::char_traits<char>, std::__1::allocator<char>>*, lldb_private::ValueObject*) Target.cpp:2905 08:15:39 llvm#7 0x00011fc7bde0 in lldb::SBTarget::EvaluateExpression(char const*, lldb::SBExpressionOptions const&) SBTarget.cpp:2305 08:15:39 ==61103==ABORTING ... ```
Member
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@llvm/pr-subscribers-lldb Author: Michael Buch (Michael137) ChangesThis got exposed by The underlying stream of The ASAN macOS bot is currently failing with this: Full diff: https://github.com/llvm/llvm-project/pull/167724.diff 1 Files Affected:
diff --git a/lldb/source/Plugins/ExpressionParser/Clang/ClangModulesDeclVendor.cpp b/lldb/source/Plugins/ExpressionParser/Clang/ClangModulesDeclVendor.cpp
index 7635e49051216..dd61937933490 100644
--- a/lldb/source/Plugins/ExpressionParser/Clang/ClangModulesDeclVendor.cpp
+++ b/lldb/source/Plugins/ExpressionParser/Clang/ClangModulesDeclVendor.cpp
@@ -67,11 +67,11 @@ class StoringDiagnosticConsumer : public clang::DiagnosticConsumer {
IDAndDiagnostic;
std::vector<IDAndDiagnostic> m_diagnostics;
std::unique_ptr<clang::DiagnosticOptions> m_diag_opts;
+ /// Output stream of m_diag_printer.
+ std::unique_ptr<llvm::raw_string_ostream> m_os;
/// The DiagnosticPrinter used for creating the full diagnostic messages
/// that are stored in m_diagnostics.
std::unique_ptr<clang::TextDiagnosticPrinter> m_diag_printer;
- /// Output stream of m_diag_printer.
- std::unique_ptr<llvm::raw_string_ostream> m_os;
/// Output string filled by m_os. Will be reused for different diagnostics.
std::string m_output;
/// A Progress with explicitly managed lifetime.
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Michael137
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to Michael137/llvm-project
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Nov 12, 2025
…iagnosticManagerAdapter This aligns `ClangDiagnosticManagerAdapter` with how we set up the diagnostics in `ClangModulesDeclVendor`. We fixed lifetime issues around the same kind of setup here: llvm#167724 This class didn't suffer from the same lifetime issue because it used `shared_ptr`s. So the stream wasn't freed before `~TextDiagnosticPrinter` accessing it. But that begged the question of why these are `shared_ptr`s in the first place. This patch makes these `unique_ptr`s and fixes the destruction order that would now be an issue.
Michael137
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to swiftlang/llvm-project
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Nov 12, 2025
…am (llvm#167724) This got exposed by `09262656f32ab3f2e1d82e5342ba37eecac52522`. The underlying stream of `m_os` is referenced by the `TextDiagnostic` member of `TextDiagnosticPrinter`. It got turned into a `llvm::formatted_raw_ostream` in the commit above. When `~TextDiagnosticPrinter` (and thus `~TextDiagnostic`) is invoked, we now call `~formatted_raw_ostream`, which tries to access the underlying stream. But `m_os` was already deleted because it is earlier in the order of destruction in `TextDiagnosticPrinter`. Move the `m_os` member before the `TextDiagnosticPrinter` to avoid a use-after-free. Drive-by: * Also move the `m_output` member which the `m_os` holds a reference to. The fact it's a reference indicates the expectation is most likely that the string outlives the stream. The ASAN macOS bot is currently failing with this: ``` 08:15:39 ================================================================= 08:15:39 ==61103==ERROR: AddressSanitizer: heap-use-after-free on address 0x60600012cf40 at pc 0x00012140d304 bp 0x00016eecc850 sp 0x00016eecc848 08:15:39 READ of size 8 at 0x60600012cf40 thread T0 08:15:39 #0 0x00012140d300 in llvm::formatted_raw_ostream::releaseStream() FormattedStream.h:205 08:15:39 #1 0x00012140d3a4 in llvm::formatted_raw_ostream::~formatted_raw_ostream() FormattedStream.h:145 08:15:39 #2 0x00012604abf8 in clang::TextDiagnostic::~TextDiagnostic() TextDiagnostic.cpp:721 08:15:39 #3 0x00012605dc80 in clang::TextDiagnosticPrinter::~TextDiagnosticPrinter() TextDiagnosticPrinter.cpp:30 08:15:39 #4 0x00012605dd5c in clang::TextDiagnosticPrinter::~TextDiagnosticPrinter() TextDiagnosticPrinter.cpp:27 08:15:39 #5 0x0001231fb210 in (anonymous namespace)::StoringDiagnosticConsumer::~StoringDiagnosticConsumer() ClangModulesDeclVendor.cpp:47 08:15:39 #6 0x0001231fb3bc in (anonymous namespace)::StoringDiagnosticConsumer::~StoringDiagnosticConsumer() ClangModulesDeclVendor.cpp:47 08:15:39 #7 0x000129aa9d70 in clang::DiagnosticsEngine::~DiagnosticsEngine() Diagnostic.cpp:91 08:15:39 #8 0x0001230436b8 in llvm::RefCountedBase<clang::DiagnosticsEngine>::Release() const IntrusiveRefCntPtr.h:103 08:15:39 #9 0x0001231fe6c8 in (anonymous namespace)::ClangModulesDeclVendorImpl::~ClangModulesDeclVendorImpl() ClangModulesDeclVendor.cpp:93 08:15:39 #10 0x0001231fe858 in (anonymous namespace)::ClangModulesDeclVendorImpl::~ClangModulesDeclVendorImpl() ClangModulesDeclVendor.cpp:93 ... 08:15:39 08:15:39 0x60600012cf40 is located 32 bytes inside of 56-byte region [0x60600012cf20,0x60600012cf58) 08:15:39 freed by thread T0 here: 08:15:39 #0 0x0001018abb88 in _ZdlPv+0x74 (libclang_rt.asan_osx_dynamic.dylib:arm64e+0x4bb88) 08:15:39 #1 0x0001231fb1c0 in (anonymous namespace)::StoringDiagnosticConsumer::~StoringDiagnosticConsumer() ClangModulesDeclVendor.cpp:47 08:15:39 #2 0x0001231fb3bc in (anonymous namespace)::StoringDiagnosticConsumer::~StoringDiagnosticConsumer() ClangModulesDeclVendor.cpp:47 08:15:39 #3 0x000129aa9d70 in clang::DiagnosticsEngine::~DiagnosticsEngine() Diagnostic.cpp:91 08:15:39 #4 0x0001230436b8 in llvm::RefCountedBase<clang::DiagnosticsEngine>::Release() const IntrusiveRefCntPtr.h:103 08:15:39 #5 0x0001231fe6c8 in (anonymous namespace)::ClangModulesDeclVendorImpl::~ClangModulesDeclVendorImpl() ClangModulesDeclVendor.cpp:93 08:15:39 #6 0x0001231fe858 in (anonymous namespace)::ClangModulesDeclVendorImpl::~ClangModulesDeclVendorImpl() ClangModulesDeclVendor.cpp:93 ... 08:15:39 08:15:39 previously allocated by thread T0 here: 08:15:39 #0 0x0001018ab760 in _Znwm+0x74 (libclang_rt.asan_osx_dynamic.dylib:arm64e+0x4b760) 08:15:39 #1 0x0001231f8dec in lldb_private::ClangModulesDeclVendor::Create(lldb_private::Target&) ClangModulesDeclVendor.cpp:732 08:15:39 #2 0x00012320af58 in lldb_private::ClangPersistentVariables::GetClangModulesDeclVendor() ClangPersistentVariables.cpp:124 08:15:39 #3 0x0001232111f0 in lldb_private::ClangUserExpression::PrepareForParsing(lldb_private::DiagnosticManager&, lldb_private::ExecutionContext&, bool) ClangUserExpression.cpp:536 08:15:39 #4 0x000123213790 in lldb_private::ClangUserExpression::Parse(lldb_private::DiagnosticManager&, lldb_private::ExecutionContext&, lldb_private::ExecutionPolicy, bool, bool) ClangUserExpression.cpp:647 08:15:39 #5 0x00012032b258 in lldb_private::UserExpression::Evaluate(lldb_private::ExecutionContext&, lldb_private::EvaluateExpressionOptions const&, llvm::StringRef, llvm::StringRef, std::__1::shared_ptr<lldb_private::ValueObject>&, std::__1::basic_string<char, std::__1::char_traits<char>, std::__1::allocator<char>>*, lldb_private::ValueObject*) UserExpression.cpp:280 08:15:39 #6 0x000120724010 in lldb_private::Target::EvaluateExpression(llvm::StringRef, lldb_private::ExecutionContextScope*, std::__1::shared_ptr<lldb_private::ValueObject>&, lldb_private::EvaluateExpressionOptions const&, std::__1::basic_string<char, std::__1::char_traits<char>, std::__1::allocator<char>>*, lldb_private::ValueObject*) Target.cpp:2905 08:15:39 #7 0x00011fc7bde0 in lldb::SBTarget::EvaluateExpression(char const*, lldb::SBExpressionOptions const&) SBTarget.cpp:2305 08:15:39 ==61103==ABORTING ... ``` (cherry picked from commit b9eb974)
Michael137
added a commit
that referenced
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Nov 12, 2025
…iagnosticManagerAdapter (#167731) This aligns `ClangDiagnosticManagerAdapter` with how we set up the diagnostics in `ClangModulesDeclVendor`. We fixed lifetime issues around the same kind of setup here: #167724 This class didn't suffer from the same lifetime issue because it used `shared_ptr`s. So the stream wasn't freed before `~TextDiagnosticPrinter` accessing it. But that begged the question of why these are `shared_ptr`s in the first place. This patch makes these `unique_ptr`s and fixes the destruction order that would now be an issue.
llvm-sync bot
pushed a commit
to arm/arm-toolchain
that referenced
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Nov 12, 2025
…s in ClangDiagnosticManagerAdapter (#167731) This aligns `ClangDiagnosticManagerAdapter` with how we set up the diagnostics in `ClangModulesDeclVendor`. We fixed lifetime issues around the same kind of setup here: llvm/llvm-project#167724 This class didn't suffer from the same lifetime issue because it used `shared_ptr`s. So the stream wasn't freed before `~TextDiagnosticPrinter` accessing it. But that begged the question of why these are `shared_ptr`s in the first place. This patch makes these `unique_ptr`s and fixes the destruction order that would now be an issue.
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This got exposed by
09262656f32ab3f2e1d82e5342ba37eecac52522.The underlying stream of
m_osis referenced by theTextDiagnosticmember ofTextDiagnosticPrinter. It got turned into allvm::formatted_raw_ostreamin the commit above. When~TextDiagnosticPrinter(and thus~TextDiagnostic) is invoked, we now call~formatted_raw_ostream, which tries to access the underlying stream. Butm_oswas already deleted because it is earlier in the order of destruction inTextDiagnosticPrinter. Move them_osmember before theTextDiagnosticPrinterto avoid a use-after-free.Drive-by:
m_outputmember which them_osholds a reference to. The fact it's a reference indicates the expectation is most likely that the string outlives the stream.The ASAN macOS bot is currently failing with this: