r233491 - [lex] Don't read past the end of the buffer

[Benjamin Kramer]

Author: d0k
Date: Sun Mar 29 09:11:37 2015
New Revision: 233491

URL: http://llvm.org/viewvc/llvm-project?rev=233491&view=rev
Log:
[lex] Don't read past the end of the buffer

While dereferencing ThisTokEnd is fine and we know that it's not in
[a-zA-Z0-9_.], ThisTokEnd[1] is really past the end.

Found by asan and with a little help from clang-fuzz.

Added:
    cfe/trunk/test/Lexer/eof-number.c
Modified:
    cfe/trunk/lib/Lex/LiteralSupport.cpp

Modified: cfe/trunk/lib/Lex/LiteralSupport.cpp
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/lib/Lex/LiteralSupport.cpp?rev=233491&r1=233490&r2=233491&view=diff
==============================================================================
--- cfe/trunk/lib/Lex/LiteralSupport.cpp (original)
+++ cfe/trunk/lib/Lex/LiteralSupport.cpp Sun Mar 29 09:11:37 2015
@@ -748,11 +748,11 @@ void NumericLiteralParser::ParseNumberSt
   s++;
 
   int c1 = s[0];
-  int c2 = s[1];
 
   // Handle a hex number like 0x1234.
-  if ((c1 == 'x' || c1 == 'X') && (isHexDigit(c2) || c2 == '.')) {
+  if ((c1 == 'x' || c1 == 'X') && (isHexDigit(s[1]) || s[1] == '.')) {
     s++;
+    assert(s < ThisTokEnd && "didn't maximally munch?");
     radix = 16;
     DigitsBegin = s;
     s = SkipHexDigits(s);
@@ -804,7 +804,7 @@ void NumericLiteralParser::ParseNumberSt
   }
 
   // Handle simple binary numbers 0b01010
-  if ((c1 == 'b' || c1 == 'B') && (c2 == '0' || c2 == '1')) {
+  if ((c1 == 'b' || c1 == 'B') && (s[1] == '0' || s[1] == '1')) {
     // 0b101010 is a C++1y / GCC extension.
     PP.Diag(TokLoc,
             PP.getLangOpts().CPlusPlus14
@@ -813,6 +813,7 @@ void NumericLiteralParser::ParseNumberSt
                 ? diag::ext_binary_literal_cxx14
                 : diag::ext_binary_literal);
     ++s;
+    assert(s < ThisTokEnd && "didn't maximally munch?");
     radix = 2;
     DigitsBegin = s;
     s = SkipBinaryDigits(s);

Added: cfe/trunk/test/Lexer/eof-number.c
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/test/Lexer/eof-number.c?rev=233491&view=auto
==============================================================================
--- cfe/trunk/test/Lexer/eof-number.c (added)
+++ cfe/trunk/test/Lexer/eof-number.c Sun Mar 29 09:11:37 2015
@@ -0,0 +1,9 @@
+// RUN: %clang_cc1 %s -verify -fsyntax-only -Wnewline-eof
+// vim: set binary noeol:
+
+// This file intentionally ends without a \n on the last line.  Make sure your
+// editor doesn't add one.
+
+// expected-error at +2{{unterminated conditional directive}}
+// expected-warning at +1{{no newline at end of file}}
+#if 0
\ No newline at end of file