Author: Aaron Ballman Date: 2022-05-12T13:20:35-04:00 New Revision: c671041720347c9deb35b1165ee6b6bb88abf07a
URL: https://github.com/llvm/llvm-project/commit/c671041720347c9deb35b1165ee6b6bb88abf07a DIFF: https://github.com/llvm/llvm-project/commit/c671041720347c9deb35b1165ee6b6bb88abf07a.diff LOG: Check for resource exhaustion when recursively parsing declarators With sufficiently tortured code, it's possible to cause a stack overflow when parsing declarators. Thus, we now check for resource exhaustion when recursively parsing declarators so that we can at least warn the user we're about to crash before we actually crash. Fixes #51642 Differential Revision: https://reviews.llvm.org/D124915 Added: Modified: clang/docs/ReleaseNotes.rst clang/lib/Parse/ParseDecl.cpp Removed: ################################################################################ diff --git a/clang/docs/ReleaseNotes.rst b/clang/docs/ReleaseNotes.rst index e7dd0d1d6e910..7c25456adb25a 100644 --- a/clang/docs/ReleaseNotes.rst +++ b/clang/docs/ReleaseNotes.rst @@ -222,7 +222,9 @@ Improvements to Clang's diagnostics on such language mode, ``-Wpre-c2x-compat`` and ``-Wpre-c++2b-compat`` diagnostic flags report a compatibility issue. Fixes `Issue 55306 <https://github.com/llvm/llvm-project/issues/55306>`_. - +- Clang now checks for stack resource exhaustion when recursively parsing + declarators in order to give a diagnostic before we run out of stack space. + This fixes `Issue 51642 <https://github.com/llvm/llvm-project/issues/51642>`_. Non-comprehensive list of changes in this release ------------------------------------------------- diff --git a/clang/lib/Parse/ParseDecl.cpp b/clang/lib/Parse/ParseDecl.cpp index 89e13cf5c90f9..306644fc4b21d 100644 --- a/clang/lib/Parse/ParseDecl.cpp +++ b/clang/lib/Parse/ParseDecl.cpp @@ -5765,11 +5765,12 @@ void Parser::ParseTypeQualifierListOpt( } /// ParseDeclarator - Parse and verify a newly-initialized declarator. -/// void Parser::ParseDeclarator(Declarator &D) { /// This implements the 'declarator' production in the C grammar, then checks /// for well-formedness and issues diagnostics. - ParseDeclaratorInternal(D, &Parser::ParseDirectDeclarator); + Actions.runWithSufficientStackSpace(D.getBeginLoc(), [&] { + ParseDeclaratorInternal(D, &Parser::ParseDirectDeclarator); + }); } static bool isPtrOperatorToken(tok::TokenKind Kind, const LangOptions &Lang, @@ -5880,7 +5881,9 @@ void Parser::ParseDeclaratorInternal(Declarator &D, D.ExtendWithDeclSpec(DS); // Recurse to parse whatever is left. - ParseDeclaratorInternal(D, DirectDeclParser); + Actions.runWithSufficientStackSpace(D.getBeginLoc(), [&] { + ParseDeclaratorInternal(D, DirectDeclParser); + }); // Sema will have to catch (syntactically invalid) pointers into global // scope. It has to catch pointers into namespace scope anyway. @@ -5929,7 +5932,8 @@ void Parser::ParseDeclaratorInternal(Declarator &D, D.ExtendWithDeclSpec(DS); // Recursively parse the declarator. - ParseDeclaratorInternal(D, DirectDeclParser); + Actions.runWithSufficientStackSpace( + D.getBeginLoc(), [&] { ParseDeclaratorInternal(D, DirectDeclParser); }); if (Kind == tok::star) // Remember that we parsed a pointer type, and remember the type-quals. D.AddTypeInfo(DeclaratorChunk::getPointer( @@ -5974,7 +5978,8 @@ void Parser::ParseDeclaratorInternal(Declarator &D, } // Recursively parse the declarator. - ParseDeclaratorInternal(D, DirectDeclParser); + Actions.runWithSufficientStackSpace( + D.getBeginLoc(), [&] { ParseDeclaratorInternal(D, DirectDeclParser); }); if (D.getNumTypeObjects() > 0) { // C++ [dcl.ref]p4: There shall be no references to references. _______________________________________________ cfe-commits mailing list cfe-commits@lists.llvm.org https://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits
