[libcxx-commits] [libcxxabi] acdd36e - [ItaniumDemangle] reject A-F in FP literals (#82864)

[via libcxx-commits]

Author: Ryan Prichard
Date: 2024-02-26T13:23:30-08:00
New Revision: acdd36e677e396909f700e5dfb519d907a6b4560

URL: https://github.com/llvm/llvm-project/commit/acdd36e677e396909f700e5dfb519d907a6b4560
DIFF: https://github.com/llvm/llvm-project/commit/acdd36e677e396909f700e5dfb519d907a6b4560.diff

LOG: [ItaniumDemangle] reject A-F in FP literals (#82864)

The Itanium C++ ABI specifies that FP literals are encoded using a
lowercase hexadecimal string. Previously, libc++abi allowed uppercase
A-F characters but decoded them by subtracting 'a' from them, producing
negative digit values. It is especially confusing to accept an 'E' digit
because 'E' marks the end of the FP literal.

Added: 
    

Modified: 
    libcxxabi/src/demangle/ItaniumDemangle.h
    libcxxabi/test/test_demangle.pass.cpp

Removed: 
    


################################################################################
diff  --git a/libcxxabi/src/demangle/ItaniumDemangle.h b/libcxxabi/src/demangle/ItaniumDemangle.h
index 04755e2be3c5d4..4a0444d407ea7b 100644
--- a/libcxxabi/src/demangle/ItaniumDemangle.h
+++ b/libcxxabi/src/demangle/ItaniumDemangle.h
@@ -5541,7 +5541,7 @@ Node *AbstractManglingParser<Alloc, Derived>::parseFloatingLiteral() {
     return nullptr;
   std::string_view Data(First, N);
   for (char C : Data)
-    if (!std::isxdigit(C))
+    if (!(C >= '0' && C <= '9') && !(C >= 'a' && C <= 'f'))
       return nullptr;
   First += N;
   if (!consumeIf('E'))

diff  --git a/libcxxabi/test/test_demangle.pass.cpp b/libcxxabi/test/test_demangle.pass.cpp
index b7e41099ebfc53..88637b84de016e 100644
--- a/libcxxabi/test/test_demangle.pass.cpp
+++ b/libcxxabi/test/test_demangle.pass.cpp
@@ -30222,9 +30222,8 @@ struct FPLiteralCase {
      }},
 #endif
 #if LDBL_FP128
-    // This was found by libFuzzer+HWASan on aarch64 Android.
-    {"1\006ILeeeEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEE",
-     {"\x6<-0x1.cecececececececececececececep+11983L>"}},
+    // A 32-character FP literal of long double type
+    {"3FooILeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeEE", {"Foo<-0x1.eeeeeeeeeeeeeeeeeeeeeeeeeeeep+12015L>"}},
 #endif
 };
 const unsigned NF = sizeof(fp_literal_cases) / sizeof(fp_literal_cases[0]);
@@ -30238,6 +30237,8 @@ const char* invalid_cases[] =
     "NSoERj5E=Y1[uM:ga",
     "Aon_PmKVPDk7?fg4XP5smMUL6;<WsI_mgbf23cCgsHbT<l8EE\0uVRkNOoXDrgdA4[8IU>Vl<>IL8ayHpiVDDDXTY;^o9;i",
     "_ZNSt16allocator_traitsISaIN4llvm3sys2fs18directory_iteratorEEE9constructIS3_IS3_EEEDTcl12_S_constructfp_fp0_spcl7forwardIT0_Efp1_EEERS4_PT_DpOS7_",
+    "3FooILdaaaaaaaaaaAAAAaaEE",
+    "3FooILdaaaaaaaaaaaaaaEE",
 #if !LDBL_FP80
     "_ZN5test01hIfEEvRAcvjplstT_Le4001a000000000000000E_c",
 #endif