mirror of
https://github.com/SerenityOS/serenity
synced 2024-09-06 17:06:31 +00:00
Kernel: Make sure we can allocate kernel stack before creating thread
Wrap thread creation in a Thread::try_create() helper that first allocates a kernel stack region. If that allocation fails, we propagate an ENOMEM error to the caller. This avoids the situation where a thread is half-constructed, without a valid kernel stack, and avoids having to do messy cleanup in that case.
This commit is contained in:
parent
5c45b0d32d
commit
b466ede1ea
|
@ -346,14 +346,11 @@ Process::Process(RefPtr<Thread>& first_thread, const String& name, uid_t uid, gi
|
|||
first_thread = Thread::current()->clone(*this);
|
||||
} else {
|
||||
// NOTE: This non-forked code path is only taken when the kernel creates a process "manually" (at boot.)
|
||||
first_thread = adopt(*new Thread(*this));
|
||||
auto thread_or_error = Thread::try_create(*this);
|
||||
ASSERT(!thread_or_error.is_error());
|
||||
first_thread = thread_or_error.release_value();
|
||||
first_thread->detach();
|
||||
}
|
||||
|
||||
if (first_thread && !first_thread->was_created()) {
|
||||
// We couldn't entirely create or clone this thread, abort
|
||||
first_thread = nullptr;
|
||||
}
|
||||
}
|
||||
|
||||
Process::~Process()
|
||||
|
@ -810,12 +807,11 @@ RefPtr<Thread> Process::create_kernel_thread(void (*entry)(void*), void* entry_d
|
|||
|
||||
// FIXME: Do something with guard pages?
|
||||
|
||||
auto thread = adopt(*new Thread(*this));
|
||||
if (!thread->was_created()) {
|
||||
// Could not fully create this thread
|
||||
auto thread_or_error = Thread::try_create(*this);
|
||||
if (thread_or_error.is_error())
|
||||
return {};
|
||||
}
|
||||
|
||||
auto& thread = thread_or_error.value();
|
||||
thread->set_name(name);
|
||||
thread->set_affinity(affinity);
|
||||
thread->set_priority(priority);
|
||||
|
|
|
@ -60,11 +60,11 @@ int Process::sys$create_thread(void* (*entry)(void*), Userspace<const Syscall::S
|
|||
|
||||
// FIXME: Do something with guard pages?
|
||||
|
||||
auto thread = adopt(*new Thread(*this));
|
||||
if (!thread->was_created()) {
|
||||
// Could not fully create a thread
|
||||
return -ENOMEM;
|
||||
}
|
||||
auto thread_or_error = Thread::try_create(*this);
|
||||
if (thread_or_error.is_error())
|
||||
return thread_or_error.error();
|
||||
|
||||
auto& thread = thread_or_error.value();
|
||||
|
||||
// We know this thread is not the main_thread,
|
||||
// So give it a unique name until the user calls $set_thread_name on it
|
||||
|
|
|
@ -53,20 +53,29 @@ void Thread::initialize()
|
|||
g_tid_map = new HashMap<ThreadID, Thread*>();
|
||||
}
|
||||
|
||||
Thread::Thread(NonnullRefPtr<Process> process)
|
||||
KResultOr<NonnullRefPtr<Thread>> Thread::try_create(NonnullRefPtr<Process> process)
|
||||
{
|
||||
auto kernel_stack_region = MM.allocate_kernel_region(default_kernel_stack_size, {}, Region::Access::Read | Region::Access::Write, false, AllocationStrategy::AllocateNow);
|
||||
if (!kernel_stack_region)
|
||||
return ENOMEM;
|
||||
return adopt(*new Thread(move(process), kernel_stack_region.release_nonnull()));
|
||||
}
|
||||
|
||||
Thread::Thread(NonnullRefPtr<Process> process, NonnullOwnPtr<Region> kernel_stack_region)
|
||||
: m_process(move(process))
|
||||
, m_kernel_stack_region(move(kernel_stack_region))
|
||||
, m_name(m_process->name())
|
||||
{
|
||||
bool is_first_thread = m_process->add_thread(*this);
|
||||
ArmedScopeGuard guard([&]() {
|
||||
drop_thread_count(is_first_thread);
|
||||
});
|
||||
if (is_first_thread) {
|
||||
// First thread gets TID == PID
|
||||
m_tid = m_process->pid().value();
|
||||
} else {
|
||||
m_tid = Process::allocate_pid().value();
|
||||
}
|
||||
|
||||
m_kernel_stack_region->set_name(String::formatted("Kernel stack (thread {})", m_tid.value()));
|
||||
|
||||
{
|
||||
ScopedSpinLock lock(g_tid_map_lock);
|
||||
auto result = g_tid_map->set(m_tid, this);
|
||||
|
@ -126,7 +135,6 @@ Thread::Thread(NonnullRefPtr<Process> process)
|
|||
// The finalizer is responsible for dropping this reference once this
|
||||
// thread is ready to be cleaned up.
|
||||
ref();
|
||||
guard.disarm();
|
||||
}
|
||||
|
||||
Thread::~Thread()
|
||||
|
@ -881,11 +889,10 @@ RegisterState& Thread::get_register_dump_from_stack()
|
|||
|
||||
RefPtr<Thread> Thread::clone(Process& process)
|
||||
{
|
||||
auto clone = adopt(*new Thread(process));
|
||||
if (!clone->was_created()) {
|
||||
// We failed to clone this thread
|
||||
auto thread_or_error = Thread::try_create(process);
|
||||
if (thread_or_error.is_error())
|
||||
return {};
|
||||
}
|
||||
auto& clone = thread_or_error.value();
|
||||
memcpy(clone->m_signal_action_data, m_signal_action_data, sizeof(m_signal_action_data));
|
||||
clone->m_signal_mask = m_signal_mask;
|
||||
memcpy(clone->m_fpu_state, m_fpu_state, sizeof(FPUState));
|
||||
|
|
|
@ -99,7 +99,7 @@ public:
|
|||
|
||||
static void initialize();
|
||||
|
||||
explicit Thread(NonnullRefPtr<Process>);
|
||||
static KResultOr<NonnullRefPtr<Thread>> try_create(NonnullRefPtr<Process>);
|
||||
~Thread();
|
||||
|
||||
static RefPtr<Thread> from_tid(ThreadID);
|
||||
|
@ -1157,15 +1157,15 @@ public:
|
|||
}
|
||||
#endif
|
||||
|
||||
bool was_created() const
|
||||
bool is_handling_page_fault() const
|
||||
{
|
||||
return m_kernel_stack_region;
|
||||
return m_handling_page_fault;
|
||||
}
|
||||
|
||||
bool is_handling_page_fault() const { return m_handling_page_fault; }
|
||||
void set_handling_page_fault(bool b) { m_handling_page_fault = b; }
|
||||
|
||||
private:
|
||||
Thread(NonnullRefPtr<Process>, NonnullOwnPtr<Region> kernel_stack_region);
|
||||
|
||||
IntrusiveListNode m_process_thread_list_node;
|
||||
int m_runnable_priority { -1 };
|
||||
|
||||
|
|
Loading…
Reference in a new issue