[DWARF] Fix arity of DW_OP_bra (#114136)

JDevlieghere · web-flow · commit 75b37c319125 · 2024-10-29T16:41:01.000-07:00
Found by my proof-of-concept DWARF expression evaluator fuzzer.
diff --git a/lldb/unittests/Expression/DWARFExpressionTest.cpp b/lldb/unittests/Expression/DWARFExpressionTest.cpp
@@ -181,6 +181,9 @@ TEST(DWARFExpression, DW_OP_bra) {
       }),
       // clang-format on
       llvm::HasValue(0x42));
+
+  EXPECT_THAT_ERROR(Evaluate({DW_OP_bra, 0x01, 0x00}).takeError(),
+                    llvm::Failed());
 }
 
 TEST(DWARFExpression, DW_OP_convert) {
diff --git a/llvm/include/llvm/BinaryFormat/Dwarf.def b/llvm/include/llvm/BinaryFormat/Dwarf.def
@@ -728,7 +728,7 @@ HANDLE_DW_OP(0x24, shl, 0, 2, 2, DWARF)
 HANDLE_DW_OP(0x25, shr, 0, 2, 2, DWARF)
 HANDLE_DW_OP(0x26, shra, 0, 2, 2, DWARF)
 HANDLE_DW_OP(0x27, xor, 0, 2, 2, DWARF)
-HANDLE_DW_OP(0x28, bra, 1, 0, 2, DWARF)
+HANDLE_DW_OP(0x28, bra, 1, 1, 2, DWARF)
 HANDLE_DW_OP(0x29, eq, 0, 2, 2, DWARF)
 HANDLE_DW_OP(0x2a, ge, 0, 2, 2, DWARF)
 HANDLE_DW_OP(0x2b, gt, 0, 2, 2, DWARF)

Original file line number	Diff line number	Diff line change
`@@ -181,6 +181,9 @@ TEST(DWARFExpression, DW_OP_bra) {`
`181`	`181`	`}),`
`182`	`182`	`// clang-format on`
`183`	`183`	`llvm::HasValue(0x42));`
	`184`	`+`
	`185`	`+ EXPECT_THAT_ERROR(Evaluate({DW_OP_bra, 0x01, 0x00}).takeError(),`
	`186`	`+ llvm::Failed());`
`184`	`187`	`}`
`185`	`188`
`186`	`189`	`TEST(DWARFExpression, DW_OP_convert) {`