From 985f0e9ca5905af7791f39fddd005f0c9f8fe081 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Tor=20Arne=20Vestb=C3=B8?= <tor.arne.vestbo@qt.io>
Date: Wed, 19 Jan 2022 12:45:37 +0100
Subject: [PATCH] macOS: Don't print stack trace via lldb on test failure if
 SIP prevents it

If the CSR_ALLOW_UNRESTRICTED_FS bit of System Integrity Protection (SIP)
is enabled lldb will fail to print a valid stack trace when launched from
the crashed process, and might also resulting in hanging or crashing the
parent process (Terminal e.g.):

  https://github.com/llvm/llvm-project/issues/53254

We detect this situation and avoid printing a stack trace if so.

Pick-to: 6.3 6.2
Change-Id: Iad8cab5fcdc545d810ca4d4e985aefc0988d0234
Reviewed-by: Timur Pocheptsov <timur.pocheptsov@qt.io>
---
 src/corelib/kernel/qcore_mac.mm  | 33 ++++++++++++++++++++++++++++++++
 src/corelib/kernel/qcore_mac_p.h |  1 +
 src/testlib/qtestcase.cpp        |  9 ++++++++-
 3 files changed, 42 insertions(+), 1 deletion(-)

diff --git a/src/corelib/kernel/qcore_mac.mm b/src/corelib/kernel/qcore_mac.mm
index 435b2a61506..162e55fa0da 100644
--- a/src/corelib/kernel/qcore_mac.mm
+++ b/src/corelib/kernel/qcore_mac.mm
@@ -58,6 +58,7 @@
 
 #include <qdebug.h>
 
+#include "qendian.h"
 #include "qhash.h"
 #include "qpair.h"
 #include "qmutex.h"
@@ -376,6 +377,38 @@ bool qt_mac_runningUnderRosetta()
         return translated;
     return false;
 }
+
+std::optional<uint32_t> qt_mac_sipConfiguration()
+{
+    static auto configuration = []() -> std::optional<uint32_t> {
+        QIOType<io_registry_entry_t> nvram = IORegistryEntryFromPath(kIOMasterPortDefault, "IODeviceTree:/options");
+        if (!nvram) {
+            qWarning("Failed to locate NVRAM entry in IO registry");
+            return {};
+        }
+
+        QCFType<CFTypeRef> csrConfig = IORegistryEntryCreateCFProperty(nvram,
+            CFSTR("csr-active-config"), kCFAllocatorDefault, IOOptionBits{});
+        if (!csrConfig) {
+            qWarning("Failed to locate SIP config in NVRAM");
+            return {};
+        }
+
+        if (auto type = CFGetTypeID(csrConfig); type != CFDataGetTypeID()) {
+            qWarning() << "Unexpected SIP config type" << CFCopyTypeIDDescription(type);
+            return {};
+        }
+
+        QByteArray data = QByteArray::fromRawCFData(csrConfig.as<CFDataRef>());
+        if (data.size() != sizeof(uint32_t)) {
+            qWarning() << "Unexpected SIP config size" << data.size();
+            return {};
+        }
+
+        return qFromLittleEndian<uint32_t>(data.constData());
+    }();
+    return configuration;
+}
 #endif
 
 bool qt_apple_isApplicationExtension()
diff --git a/src/corelib/kernel/qcore_mac_p.h b/src/corelib/kernel/qcore_mac_p.h
index 05bd5b7baa5..0000f3b656c 100644
--- a/src/corelib/kernel/qcore_mac_p.h
+++ b/src/corelib/kernel/qcore_mac_p.h
@@ -207,6 +207,7 @@ private:
 #ifdef Q_OS_MACOS
 Q_CORE_EXPORT bool qt_mac_applicationIsInDarkMode();
 Q_CORE_EXPORT bool qt_mac_runningUnderRosetta();
+Q_CORE_EXPORT std::optional<uint32_t> qt_mac_sipConfiguration();
 #endif
 
 #ifndef QT_NO_DEBUG_STREAM
diff --git a/src/testlib/qtestcase.cpp b/src/testlib/qtestcase.cpp
index 673605307fc..ee94cdde440 100644
--- a/src/testlib/qtestcase.cpp
+++ b/src/testlib/qtestcase.cpp
@@ -212,7 +212,14 @@ static void stackTrace()
     if (debuggerPresent() || hasSystemCrashReporter())
         return;
 
-#if defined(Q_OS_LINUX) || (defined(Q_OS_MACOS) && !defined(Q_PROCESSOR_ARM_64))
+#if defined(Q_OS_LINUX) || defined(Q_OS_MACOS)
+
+#if defined(Q_OS_MACOS)
+    #define CSR_ALLOW_UNRESTRICTED_FS (1 << 1)
+    std::optional<uint32_t> sipConfiguration = qt_mac_sipConfiguration();
+    if (!sipConfiguration || !(*sipConfiguration & CSR_ALLOW_UNRESTRICTED_FS))
+        return; // LLDB will fail to provide a valid stack trace
+#endif
 
     const int msecsFunctionTime = qRound(QTestLog::msecsFunctionTime());
     const int msecsTotalTime = qRound(QTestLog::msecsTotalTime());