diff options
| author | Thiago Macieira <thiago.macieira@intel.com> | 2014-05-19 16:53:34 -0700 |
|---|---|---|
| committer | The Qt Project <gerrit-noreply@qt-project.org> | 2014-05-21 01:34:38 +0200 |
| commit | 5283a6c87beac5a43f612786fefd6e43f2c70bf6 (patch) | |
| tree | 48c1648a29305a3567e51bdd1f98ae4b7a64dfed | |
| parent | 1b031630ded1fbb9a94642de1d720651a390a03b (diff) | |
Disable hash seeding for bootstrapped tools
Any bootstrapped tool is a development tool, by definition. So the
effects of seeding the hash with a random number can cause the same
source input to produce different binary results, which can throw some
caching tools into disarray (like the Open Build System).
There should be minimal fall out from the reduced protection against
DoS. Since those are only development tools, "specially crafted" input
implies the developer is DoS'ing him/herself.
Note: the change to qhash.cpp applies to moc and rcc, which are always
bootstrapped.
Change-Id: I061ab52036e40627c0703f1bf881455cbf848f43
Reviewed-by: Oswald Buddenhagen <oswald.buddenhagen@digia.com>
Reviewed-by: hjk <hjk121@nokiamail.com>
| -rw-r--r-- | src/corelib/tools/qhash.cpp | 8 | ||||
| -rw-r--r-- | src/tools/qdoc/main.cpp | 2 | ||||
| -rw-r--r-- | src/tools/uic/main.cpp | 3 |
3 files changed, 9 insertions, 4 deletions
diff --git a/src/corelib/tools/qhash.cpp b/src/corelib/tools/qhash.cpp index ca645636e4..7200ea7993 100644 --- a/src/corelib/tools/qhash.cpp +++ b/src/corelib/tools/qhash.cpp @@ -222,12 +222,13 @@ uint qHash(QLatin1String key, uint seed) Q_DECL_NOTHROW */ static uint qt_create_qhash_seed() { + uint seed = 0; + +#ifndef QT_BOOTSTRAPPED QByteArray envSeed = qgetenv("QT_HASH_SEED"); if (!envSeed.isNull()) return envSeed.toUInt(); - uint seed = 0; - #ifdef Q_OS_UNIX int randomfd = qt_safe_open("/dev/urandom", O_RDONLY); if (randomfd == -1) @@ -254,17 +255,16 @@ static uint qt_create_qhash_seed() seed ^= timestamp; seed ^= (timestamp >> 32); -#ifndef QT_BOOTSTRAPPED quint64 pid = QCoreApplication::applicationPid(); seed ^= pid; seed ^= (pid >> 32); -#endif // QT_BOOTSTRAPPED quintptr seedPtr = reinterpret_cast<quintptr>(&seed); seed ^= seedPtr; #if QT_POINTER_SIZE == 8 seed ^= (seedPtr >> 32); #endif +#endif // QT_BOOTSTRAPPED return seed; } diff --git a/src/tools/qdoc/main.cpp b/src/tools/qdoc/main.cpp index 398d188464..3d2ee409b0 100644 --- a/src/tools/qdoc/main.cpp +++ b/src/tools/qdoc/main.cpp @@ -542,6 +542,7 @@ static void processQdocconfFile(const QString &fileName) Generator::debugSegfault("qdoc finished!"); } +extern Q_CORE_EXPORT QBasicAtomicInt qt_qhash_seed; QT_END_NAMESPACE int main(int argc, char **argv) @@ -549,6 +550,7 @@ int main(int argc, char **argv) QT_USE_NAMESPACE #ifndef QT_BOOTSTRAPPED + qt_qhash_seed.testAndSetRelaxed(-1, 0); // set the hash seed to 0 if it wasn't set yet QCoreApplication app(argc, argv); #endif diff --git a/src/tools/uic/main.cpp b/src/tools/uic/main.cpp index cb2bd430ff..12b0ee6737 100644 --- a/src/tools/uic/main.cpp +++ b/src/tools/uic/main.cpp @@ -52,9 +52,12 @@ #include <qcommandlineparser.h> QT_BEGIN_NAMESPACE +extern Q_CORE_EXPORT QBasicAtomicInt qt_qhash_seed; int runUic(int argc, char *argv[]) { + qt_qhash_seed.testAndSetRelaxed(-1, 0); // set the hash seed to 0 if it wasn't set yet + QCoreApplication app(argc, argv); QCoreApplication::setApplicationVersion(QString::fromLatin1(QT_VERSION_STR)); |