diff --git a/lib/Support/Unix/Signals.inc b/lib/Support/Unix/Signals.inc index cf64fa8f385..9e94068c9c3 100644 --- a/lib/Support/Unix/Signals.inc +++ b/lib/Support/Unix/Signals.inc @@ -121,17 +121,29 @@ static void UnregisterHandlers() { /// NB: This must be an async signal safe function. It cannot allocate or free /// memory, even in debug builds. static void RemoveFilesToRemove() { - // Note: avoid iterators in case of debug iterators that allocate or release + // We avoid iterators in case of debug iterators that allocate or release // memory. for (unsigned i = 0, e = FilesToRemove.size(); i != e; ++i) { - // Note that we don't want to use any external code here, and we don't care - // about errors. We're going to try as hard as we can as often as we need - // to to make these files go away. If these aren't files, too bad. - // - // We do however rely on a std::string implementation for which repeated - // calls to 'c_str()' don't allocate memory. We pre-call 'c_str()' on all - // of these strings to try to ensure this is safe. - unlink(FilesToRemove[i].c_str()); + // We rely on a std::string implementation for which repeated calls to + // 'c_str()' don't allocate memory. We pre-call 'c_str()' on all of these + // strings to try to ensure this is safe. + const char *path = FilesToRemove[i].c_str(); + + // Get the status so we can determine if it's a file or directory. If we + // can't stat the file, ignore it. + struct stat buf; + if (stat(path, &buf) != 0) + continue; + + // If this is not a regular file, ignore it. We want to prevent removal of + // special files like /dev/null, even if the compiler is being run with the + // super-user permissions. + if (!S_ISREG(buf.st_mode)) + continue; + + // Otherwise, remove the file. We ignore any errors here as there is nothing + // else we can do. + unlink(path); } }