From f2f2572fed075d2dca5ae7abcea451ac5eb382ec Mon Sep 17 00:00:00 2001
From: Subv <subv2112@gmail.com>
Date: Wed, 11 Jan 2017 12:08:10 -0500
Subject: [PATCH] Thread: Added priority range checking to svcSetThreadPriority
 and removed priority clamping code from Thread::SetPriority.

---
 src/core/hle/kernel/resource_limit.cpp |  2 ++
 src/core/hle/kernel/thread.cpp         | 20 ++------------------
 src/core/hle/svc.cpp                   | 14 ++++++++++++++
 3 files changed, 18 insertions(+), 18 deletions(-)

diff --git a/src/core/hle/kernel/resource_limit.cpp b/src/core/hle/kernel/resource_limit.cpp
index 253ab7045..3f51bc5de 100644
--- a/src/core/hle/kernel/resource_limit.cpp
+++ b/src/core/hle/kernel/resource_limit.cpp
@@ -62,6 +62,8 @@ s32 ResourceLimit::GetCurrentResourceValue(u32 resource) const {
 
 s32 ResourceLimit::GetMaxResourceValue(u32 resource) const {
     switch (resource) {
+    case PRIORITY:
+        return max_priority;
     case COMMIT:
         return max_commit;
     case THREAD:
diff --git a/src/core/hle/kernel/thread.cpp b/src/core/hle/kernel/thread.cpp
index 8c6fbcd04..5ba9abf29 100644
--- a/src/core/hle/kernel/thread.cpp
+++ b/src/core/hle/kernel/thread.cpp
@@ -444,25 +444,9 @@ ResultVal<SharedPtr<Thread>> Thread::Create(std::string name, VAddr entry_point,
     return MakeResult<SharedPtr<Thread>>(std::move(thread));
 }
 
-// TODO(peachum): Remove this. Range checking should be done, and an appropriate error should be
-// returned.
-static void ClampPriority(const Thread* thread, s32* priority) {
-    if (*priority < THREADPRIO_HIGHEST || *priority > THREADPRIO_LOWEST) {
-        DEBUG_ASSERT_MSG(
-            false, "Application passed an out of range priority. An error should be returned.");
-
-        s32 new_priority = MathUtil::Clamp<s32>(*priority, THREADPRIO_HIGHEST, THREADPRIO_LOWEST);
-        LOG_WARNING(Kernel_SVC, "(name=%s): invalid priority=%d, clamping to %d",
-                    thread->name.c_str(), *priority, new_priority);
-        // TODO(bunnei): Clamping to a valid priority is not necessarily correct behavior... Confirm
-        // validity of this
-        *priority = new_priority;
-    }
-}
-
 void Thread::SetPriority(s32 priority) {
-    ClampPriority(this, &priority);
-
+    ASSERT_MSG(priority <= THREADPRIO_LOWEST && priority >= THREADPRIO_HIGHEST,
+               "Invalid priority value.");
     // If thread was ready, adjust queues
     if (status == THREADSTATUS_READY)
         ready_queue.move(this, current_priority, priority);
diff --git a/src/core/hle/svc.cpp b/src/core/hle/svc.cpp
index 2b242ff98..8cb6a1c94 100644
--- a/src/core/hle/svc.cpp
+++ b/src/core/hle/svc.cpp
@@ -598,10 +598,24 @@ static ResultCode GetThreadPriority(s32* priority, Kernel::Handle handle) {
 
 /// Sets the priority for the specified thread
 static ResultCode SetThreadPriority(Kernel::Handle handle, s32 priority) {
+    if (priority > THREADPRIO_LOWEST) {
+        return ResultCode(ErrorDescription::OutOfRange, ErrorModule::OS,
+                          ErrorSummary::InvalidArgument, ErrorLevel::Usage);
+    }
+
     SharedPtr<Kernel::Thread> thread = Kernel::g_handle_table.Get<Kernel::Thread>(handle);
     if (thread == nullptr)
         return ERR_INVALID_HANDLE;
 
+    using Kernel::ResourceLimit;
+    // Note: The kernel uses the current process's resource limit instead of
+    // the one from the thread owner's resource limit.
+    Kernel::SharedPtr<ResourceLimit>& resource_limit = Kernel::g_current_process->resource_limit;
+    if (resource_limit->GetMaxResourceValue(Kernel::ResourceTypes::PRIORITY) > priority) {
+        return ResultCode(ErrorDescription::NotAuthorized, ErrorModule::OS,
+                          ErrorSummary::WrongArgument, ErrorLevel::Permanent);
+    }
+
     thread->SetPriority(priority);
     thread->UpdatePriority();