diff options
Diffstat (limited to 'src/corelib')
| -rw-r--r-- | src/corelib/io/qstandardpaths_unix.cpp | 162 |
1 files changed, 120 insertions, 42 deletions
diff --git a/src/corelib/io/qstandardpaths_unix.cpp b/src/corelib/io/qstandardpaths_unix.cpp index 748ce67dac..d71a28432d 100644 --- a/src/corelib/io/qstandardpaths_unix.cpp +++ b/src/corelib/io/qstandardpaths_unix.cpp @@ -1,6 +1,7 @@ /**************************************************************************** ** -** Copyright (C) 2016 The Qt Company Ltd. +** Copyright (C) 2020 The Qt Company Ltd. +** Copyright (C) 2020 Intel Corporation. ** Contact: https://www.qt.io/licensing/ ** ** This file is part of the QtCore module of the Qt Toolkit. @@ -71,6 +72,111 @@ static void appendOrganizationAndApp(QString &path) #endif } +static bool checkXdgRuntimeDir(const QString &xdgRuntimeDir) +{ + auto describeMetaData = [](const QFileSystemMetaData &metaData) -> QByteArray { + if (!metaData.exists()) + return "a broken symlink"; + + QByteArray description; + if (metaData.isLink()) + description = "a symbolic link to "; + + if (metaData.isFile()) + description += "a regular file"; + else if (metaData.isDirectory()) + description += "a directory"; + else if (metaData.isSequential()) + description += "a character device, socket or FIFO"; + else + description += "a block device"; + + // convert QFileSystemMetaData permissions back to Unix + mode_t perms = 0; + if (metaData.permissions() & QFile::ReadOwner) + perms |= S_IRUSR; + if (metaData.permissions() & QFile::WriteOwner) + perms |= S_IWUSR; + if (metaData.permissions() & QFile::ExeOwner) + perms |= S_IXUSR; + if (metaData.permissions() & QFile::ReadGroup) + perms |= S_IRGRP; + if (metaData.permissions() & QFile::WriteGroup) + perms |= S_IWGRP; + if (metaData.permissions() & QFile::ExeGroup) + perms |= S_IXGRP; + if (metaData.permissions() & QFile::ReadOther) + perms |= S_IROTH; + if (metaData.permissions() & QFile::WriteOther) + perms |= S_IWOTH; + if (metaData.permissions() & QFile::ExeOther) + perms |= S_IXOTH; + description += " permissions 0" + QByteArray::number(perms, 8); + + return description + + " owned by UID " + QByteArray::number(metaData.userId()) + + " GID " + QByteArray::number(metaData.groupId()); + }; + + // http://standards.freedesktop.org/basedir-spec/latest/ + const uint myUid = uint(geteuid()); + const QFile::Permissions wantedPerms = QFile::ReadOwner | QFile::WriteOwner | QFile::ExeOwner; + const QFileSystemMetaData::MetaDataFlags statFlags = QFileSystemMetaData::PosixStatFlags + | QFileSystemMetaData::LinkType; + QFileSystemMetaData metaData; + QFileSystemEntry entry(xdgRuntimeDir); + + // Check that the xdgRuntimeDir is a directory by attempting to create it. + // A stat() before mkdir() that concluded it doesn't exist is a meaningless + // result: we'd race against someone else attempting to create it. + // ### QFileSystemEngine::createDirectory cannot take the extra mode argument. + if (QT_MKDIR(entry.nativeFilePath(), 0700) == 0) + return true; + if (errno != EEXIST) { + qErrnoWarning("QStandardPaths: error creating runtime directory '%ls'", + qUtf16Printable(xdgRuntimeDir)); + return false; + } + + // We use LinkType to force an lstat(), but fillMetaData() still returns error + // on broken symlinks. + if (!QFileSystemEngine::fillMetaData(entry, metaData, statFlags) && !metaData.isLink()) { + qErrnoWarning("QStandardPaths: error obtaining permissions of runtime directory '%ls'", + qUtf16Printable(xdgRuntimeDir)); + return false; + } + + // Checks: + // - is a directory + // - is not a symlink (even is pointing to a directory) + if (metaData.isLink() || !metaData.isDirectory()) { + qWarning("QStandardPaths: runtime directory '%ls' is not a directory, but %s", + qUtf16Printable(xdgRuntimeDir), describeMetaData(metaData).constData()); + return false; + } + + // - "The directory MUST be owned by the user" + if (metaData.userId() != myUid) { + qWarning("QStandardPaths: runtime directory '%ls' is not owned by UID %d, but %s", + qUtf16Printable(xdgRuntimeDir), myUid, describeMetaData(metaData).constData()); + return false; + } + + // "and he MUST be the only one having read and write access to it. Its Unix access mode MUST be 0700." + if (metaData.permissions() != wantedPerms) { + // attempt to correct: + QSystemError error; + if (!QFileSystemEngine::setPermissions(entry, wantedPerms, error)) { + qErrnoWarning("QStandardPaths: could not set correct permissions on runtime directory " + "'%ls', which is %s", qUtf16Printable(xdgRuntimeDir), + describeMetaData(metaData).constData()); + return false; + } + } + + return true; +} + QString QStandardPaths::writableLocation(StandardLocation type) { switch (type) { @@ -120,52 +226,24 @@ QString QStandardPaths::writableLocation(StandardLocation type) } case RuntimeLocation: { - const uint myUid = uint(geteuid()); - // http://standards.freedesktop.org/basedir-spec/latest/ - QFileInfo fileInfo; QString xdgRuntimeDir = QFile::decodeName(qgetenv("XDG_RUNTIME_DIR")); - if (xdgRuntimeDir.isEmpty()) { + bool fromEnv = !xdgRuntimeDir.isEmpty(); + if (xdgRuntimeDir.isEmpty() || !checkXdgRuntimeDir(xdgRuntimeDir)) { + // environment variable not set or is set to something unsuitable + const uint myUid = uint(geteuid()); const QString userName = QFileSystemEngine::resolveUserName(myUid); xdgRuntimeDir = QDir::tempPath() + QLatin1String("/runtime-") + userName; - fileInfo.setFile(xdgRuntimeDir); - if (!fileInfo.isDir()) { - if (!QDir().mkdir(xdgRuntimeDir)) { - qWarning("QStandardPaths: error creating runtime directory %s: %s", qPrintable(xdgRuntimeDir), qPrintable(qt_error_string(errno))); - return QString(); - } - } - qWarning("QStandardPaths: XDG_RUNTIME_DIR not set, defaulting to '%s'", qPrintable(xdgRuntimeDir)); - } else { - fileInfo.setFile(xdgRuntimeDir); - if (!fileInfo.exists()) { - qWarning("QStandardPaths: XDG_RUNTIME_DIR points to non-existing path '%s', " - "please create it with 0700 permissions.", qPrintable(xdgRuntimeDir)); - return QString(); - } - if (!fileInfo.isDir()) { - qWarning("QStandardPaths: XDG_RUNTIME_DIR points to '%s' which is not a directory", - qPrintable(xdgRuntimeDir)); - return QString(); - } - } - // "The directory MUST be owned by the user" - if (fileInfo.ownerId() != myUid) { - qWarning("QStandardPaths: wrong ownership on runtime directory %s, %d instead of %d", qPrintable(xdgRuntimeDir), - fileInfo.ownerId(), myUid); - return QString(); - } - // "and he MUST be the only one having read and write access to it. Its Unix access mode MUST be 0700." - // since the current user is the owner, set both xxxUser and xxxOwner - const QFile::Permissions wantedPerms = QFile::ReadUser | QFile::WriteUser | QFile::ExeUser - | QFile::ReadOwner | QFile::WriteOwner | QFile::ExeOwner; - if (fileInfo.permissions() != wantedPerms) { - QFile file(xdgRuntimeDir); - if (!file.setPermissions(wantedPerms)) { - qWarning("QStandardPaths: could not set correct permissions on runtime directory %s: %s", - qPrintable(xdgRuntimeDir), qPrintable(file.errorString())); - return QString(); + + if (!fromEnv) { +#ifndef Q_OS_WASM + qWarning("QStandardPaths: XDG_RUNTIME_DIR not set, defaulting to '%ls'", qUtf16Printable(xdgRuntimeDir)); +#endif } + + if (!checkXdgRuntimeDir(xdgRuntimeDir)) + xdgRuntimeDir.clear(); } + return xdgRuntimeDir; } default: |