[PATCH] D41423: [Lex] Avoid out-of-bounds dereference in LexAngledStringLiteral.

[Duncan P. N. Exon Smith via Phabricator via cfe-commits]

dexonsmith requested changes to this revision.
dexonsmith added inline comments.
This revision now requires changes to proceed.


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Comment at: clang/lib/Lex/Lexer.cpp:2014-2015
+    // getAndAdvanceChar.
+    if (C == '\\')
+      C = getAndAdvanceChar(CurPtr, Result);
+
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If `CurPtr` is already equal to `BufferEnd`, why is it safe to call `getAndAdvanceChar`?  Is `BufferEnd` dereferenceable?


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Comment at: clang/lib/Lex/Lexer.cpp:2026
+
+    if (C == 0) {
       NulCharacter = CurPtr-1;
----------------
Should this check still be skipped (in an `else if` of the `C == '\\'` check)?


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Comment at: clang/unittests/Lex/LexerTest.cpp:477
 TEST_F(LexerTest, AvoidPastEndOfStringDereference) {
-  std::vector<Token> LexedTokens = Lex("  //  \\\n");
-  EXPECT_TRUE(LexedTokens.empty());
+  EXPECT_TRUE(Lex("  //  \\\n").empty());
+  // rdar://problem/35572754
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To minimize the diff, please separate this change into an NFC commit ahead of time.


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Comment at: clang/unittests/Lex/LexerTest.cpp:478
+  EXPECT_TRUE(Lex("  //  \\\n").empty());
+  // rdar://problem/35572754
+  EXPECT_TRUE(Lex("#include <\\\\").empty());
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Usually we don't put rdar/bug numbers in the source file.  It would make sense in the commit message though.


https://reviews.llvm.org/D41423