Author: benlangmuir Date: Mon May 19 11:13:45 2014 New Revision: 209138 URL: http://llvm.org/viewvc/llvm-project?rev=209138&view=rev Log: Fix use-after-free and spurious error during module load
FileManager::invalidateCache is not safe to call when there may be existing references to the file. What module load failure needs is to refresh so stale stat() info isn't stored. This may be the last user of invalidateCache; I'll take a look and remove it if possible in a future commit. This caused a use-after-free error as well as a spurious error message that a module was "found in both 'X.pcm' and 'X.pcm'" in some cases. Added: cfe/trunk/test/Modules/load-after-failure.m Modified: cfe/trunk/lib/Serialization/ModuleManager.cpp Modified: cfe/trunk/lib/Serialization/ModuleManager.cpp URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/lib/Serialization/ModuleManager.cpp?rev=209138&r1=209137&r2=209138&view=diff ============================================================================== --- cfe/trunk/lib/Serialization/ModuleManager.cpp (original) +++ cfe/trunk/lib/Serialization/ModuleManager.cpp Mon May 19 11:13:45 2014 @@ -152,9 +152,20 @@ void ModuleManager::removeModules(Module // Delete the modules and erase them from the various structures. for (ModuleIterator victim = first; victim != last; ++victim) { - Modules.erase((*victim)->File); + const FileEntry *F = (*victim)->File; + Modules.erase(F); + + // Refresh the stat() information for the module file so stale information + // doesn't get stored accidentally. + vfs::Status UpdatedStat; + if (FileMgr.getNoncachedStatValue(F->getName(), UpdatedStat)) { + llvm::report_fatal_error(Twine("module file '") + F->getName() + + "' removed after it has been used"); + } else { + FileMgr.modifyFileEntry(const_cast<FileEntry *>(F), UpdatedStat.getSize(), + UpdatedStat.getLastModificationTime().toEpochTime()); + } - FileMgr.invalidateCache((*victim)->File); if (modMap) { StringRef ModuleName = (*victim)->ModuleName; if (Module *mod = modMap->findModule(ModuleName)) { Added: cfe/trunk/test/Modules/load-after-failure.m URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/test/Modules/load-after-failure.m?rev=209138&view=auto ============================================================================== --- cfe/trunk/test/Modules/load-after-failure.m (added) +++ cfe/trunk/test/Modules/load-after-failure.m Mon May 19 11:13:45 2014 @@ -0,0 +1,25 @@ +// REQUIRES: shell +// RUN: rm -rf %t +// RUN: mkdir -p %t + +// RUN: echo '@import B;' > %t/A.h +// RUN: echo '@import C;' > %t/B.h +// RUN: echo '@import D;' >> %t/B.h +// RUN: echo '// C.h' > %t/C.h +// RUN: echo '// D.h' > %t/D.h +// RUN: echo 'module A { header "A.h" }' > %t/module.modulemap +// RUN: echo 'module B { header "B.h" }' >> %t/module.modulemap +// RUN: echo 'module C { header "C.h" }' >> %t/module.modulemap +// RUN: echo 'module D { header "D.h" }' >> %t/module.modulemap + +// RUN: %clang_cc1 -fmodules -fmodules-cache-path=%t -I %t %s -verify +// RUN: echo " " >> %t/D.h +// RUN: %clang_cc1 -fmodules -fmodules-cache-path=%t -I %t %s -verify +// expected-no-diagnostics + + +@import C; +@import A; +@import C; +// When compiling A, C will be be loaded then removed when D fails. Ensure +// this does not cause problems importing C again later. _______________________________________________ cfe-commits mailing list cfe-commits@cs.uiuc.edu http://lists.cs.uiuc.edu/mailman/listinfo/cfe-commits