[libcxxabi] r304113 - [demangler] Fix a exponential string copying bug

[Erik Pilkington via cfe-commits]

Author: epilk
Date: Sun May 28 18:15:50 2017
New Revision: 304113

URL: http://llvm.org/viewvc/llvm-project?rev=304113&view=rev
Log:
[demangler] Fix a exponential string copying bug

The problem was that if base_name() was called from a context without
an actual base name, it could gulp up the entire string, which can
result in recursive duplications. The fix is to be more strict as to
what qualifies as a base name.

Differential revision: https://reviews.llvm.org/D33637

Modified:
    libcxxabi/trunk/src/cxa_demangle.cpp
    libcxxabi/trunk/test/test_demangle.pass.cpp

Modified: libcxxabi/trunk/src/cxa_demangle.cpp
URL: http://llvm.org/viewvc/llvm-project/libcxxabi/trunk/src/cxa_demangle.cpp?rev=304113&r1=304112&r2=304113&view=diff
==============================================================================
--- libcxxabi/trunk/src/cxa_demangle.cpp (original)
+++ libcxxabi/trunk/src/cxa_demangle.cpp Sun May 28 18:15:50 2017
@@ -2915,6 +2915,10 @@ base_name(String& s)
             ++p0;
             break;
         }
+        if (!isalpha(*p0) && !isdigit(*p0) && *p0 != '_')
+        {
+            return String();
+        }
     }
     return String(p0, pe);
 }

Modified: libcxxabi/trunk/test/test_demangle.pass.cpp
URL: http://llvm.org/viewvc/llvm-project/libcxxabi/trunk/test/test_demangle.pass.cpp?rev=304113&r1=304112&r2=304113&view=diff
==============================================================================
--- libcxxabi/trunk/test/test_demangle.pass.cpp (original)
+++ libcxxabi/trunk/test/test_demangle.pass.cpp Sun May 28 18:15:50 2017
@@ -29668,6 +29668,7 @@ const char* invalid_cases[] =
     "\x46\x44\x74\x70\x74\x71\x75\x32\x43\x41\x72\x4D\x6E\x65\x34\x9F\xC1\x43\x41\x72\x4D\x6E\x77\x38\x9A\x8E\x44\x6F\x64\x6C\x53\xF9\x5F\x70\x74\x70\x69\x45\x34\xD3\x73\x9E\x2A\x37\x72\x33\x8E\x3A\x29\x8E\x44\x35",
     "_ZcvCiIJEEDvT__FFFFT_vT_v",
     "Z1JIJ1_T_EE3o00EUlT_E0",
+    "___Z2i_D1D1D1D1D1D1D1D1D1D1D1D1D1D1D1D1D1D1D1D1D1D1D1D1D1D1D1D1D1D",
 };
 
 const unsigned NI = sizeof(invalid_cases) / sizeof(invalid_cases[0]);