Author: Med Ismail Bennani Date: 2020-03-31T17:44:57+02:00 New Revision: f3a7d790df3357d52c10ec5ef48606944bcf5c6c
URL: https://github.com/llvm/llvm-project/commit/f3a7d790df3357d52c10ec5ef48606944bcf5c6c DIFF: https://github.com/llvm/llvm-project/commit/f3a7d790df3357d52c10ec5ef48606944bcf5c6c.diff LOG: [lldb/DWARF] Fix evaluator crash when accessing empty stack. This patch fixes a crash that happens on the DWARF expression evaluator when trying to access the top of the stack while it's empty. rdar://60512489 Differential Revision: https://reviews.llvm.org/D77108 Signed-off-by: Med Ismail Bennani <medismail.benn...@gmail.com> Added: Modified: lldb/source/Expression/DWARFExpression.cpp lldb/unittests/Expression/DWARFExpressionTest.cpp Removed: ################################################################################ diff --git a/lldb/source/Expression/DWARFExpression.cpp b/lldb/source/Expression/DWARFExpression.cpp index 7f12d06450c6..04fbfccd0c2e 100644 --- a/lldb/source/Expression/DWARFExpression.cpp +++ b/lldb/source/Expression/DWARFExpression.cpp @@ -2318,6 +2318,12 @@ bool DWARFExpression::Evaluate( // rather is a constant value. The value from the top of the stack is the // value to be used. This is the actual object value and not the location. case DW_OP_stack_value: + if (stack.empty()) { + if (error_ptr) + error_ptr->SetErrorString( + "Expression stack needs at least 1 item for DW_OP_stack_value."); + return false; + } stack.back().SetValueType(Value::eValueTypeScalar); break; diff --git a/lldb/unittests/Expression/DWARFExpressionTest.cpp b/lldb/unittests/Expression/DWARFExpressionTest.cpp index 64755a9066de..4c4281983078 100644 --- a/lldb/unittests/Expression/DWARFExpressionTest.cpp +++ b/lldb/unittests/Expression/DWARFExpressionTest.cpp @@ -234,6 +234,10 @@ TEST(DWARFExpression, DW_OP_convert) { llvm::Failed()); } +TEST(DWARFExpression, DW_OP_stack_value) { + EXPECT_THAT_EXPECTED(Evaluate({DW_OP_stack_value}), llvm::Failed()); +} + TEST(DWARFExpression, DW_OP_piece) { EXPECT_THAT_EXPECTED(Evaluate({DW_OP_const2u, 0x11, 0x22, DW_OP_piece, 2, DW_OP_const2u, 0x33, 0x44, DW_OP_piece, 2}), _______________________________________________ lldb-commits mailing list lldb-commits@lists.llvm.org https://lists.llvm.org/cgi-bin/mailman/listinfo/lldb-commits
