llvm-undname: Fix a crash-on-invalid
Found by oss-fuzz, fixes issues 12435 and 12438 on oss-fuzz.
Differential Revision: https://reviews.llvm.org/D60202
llvm-svn: 357646
diff --git a/llvm/lib/Demangle/MicrosoftDemangle.cpp b/llvm/lib/Demangle/MicrosoftDemangle.cpp
index c75175c..b8e39c4 100644
--- a/llvm/lib/Demangle/MicrosoftDemangle.cpp
+++ b/llvm/lib/Demangle/MicrosoftDemangle.cpp
@@ -1276,12 +1276,16 @@
return nullptr;
}
+// Returns MangledName's prefix before the first '@', or an error if
+// MangledName contains no '@' or the prefix has length 0.
StringView Demangler::demangleSimpleString(StringView &MangledName,
bool Memorize) {
StringView S;
for (size_t i = 0; i < MangledName.size(); ++i) {
if (MangledName[i] != '@')
continue;
+ if (i == 0)
+ break;
S = MangledName.substr(0, i);
MangledName = MangledName.dropFront(i + 1);
diff --git a/llvm/test/Demangle/invalid-manglings.test b/llvm/test/Demangle/invalid-manglings.test
index 365b14c..6883a46 100644
--- a/llvm/test/Demangle/invalid-manglings.test
+++ b/llvm/test/Demangle/invalid-manglings.test
@@ -8,4 +8,9 @@
?f0@@YAXPEU?$AS_@$00$$CAD@__clang@@@Z
; CHECK-EMPTY:
; CHECK-NEXT: ?f0@@YAXPEU?$AS_@$00$$CAD@__clang@@@Z
-; CHECK-NEXT: error: Invalid mangled name
\ No newline at end of file
+; CHECK-NEXT: error: Invalid mangled name
+
+?@@8
+; CHECK-EMPTY:
+; CHECK-NEXT: ?@@8
+; CHECK-NEXT: error: Invalid mangled name