The-Homebrew-Cloud/skyline
2
0
Fork 0
mirror of https://github.com/skyline-emu/skyline.git synced 2024-11-29 22:54:16 +01:00
Code Issues Packages Projects Releases Wiki Activity

Ensure that threads are ready before their preemption timer can be

Browse Source 
armed.

It was discovered during testing of 'Hatsune Miku Project DIVA: Mega Mix'
that if a thread was starting while preemption was being enabled a NULL
pointer dereference could occur in the timer_settime call as
timer_create may not have been called yet.
This commit is contained in:
Billy Laws 2021-05-30 18:15:04 +01:00
parent a7dc69223b
commit af5ee96b9a
1 changed files with 16 additions and 7 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

11
app/src/main/cpp/skyline/kernel/types/KThread.cpp
View File

@ -231,6 +231,9 @@ namespace skyline::kernel::type {
} }
void KThread::ArmPreemptionTimer(std::chrono::nanoseconds timeToFire) { void KThread::ArmPreemptionTimer(std::chrono::nanoseconds timeToFire) {
std::unique_lock lock(statusMutex);
statusCondition.wait(lock, [this]() { return ready || killed; });
if (!killed && running) {
struct itimerspec spec{.it_value = { struct itimerspec spec{.it_value = {
.tv_nsec = std::min(timeToFire.count(), static_cast<long long>(constant::NsInSecond)), .tv_nsec = std::min(timeToFire.count(), static_cast<long long>(constant::NsInSecond)),
.tv_sec = std::max(std::chrono::duration_cast<std::chrono::seconds>(timeToFire).count() - 1, 0LL), .tv_sec = std::max(std::chrono::duration_cast<std::chrono::seconds>(timeToFire).count() - 1, 0LL),
@ -238,9 +241,15 @@ namespace skyline::kernel::type {
timer_settime(preemptionTimer, 0, &spec, nullptr); timer_settime(preemptionTimer, 0, &spec, nullptr);
isPreempted = true; isPreempted = true;
} }
}
void KThread::DisarmPreemptionTimer() { void KThread::DisarmPreemptionTimer() {
if (isPreempted) { if (!isPreempted)
return;
std::unique_lock lock(statusMutex);
statusCondition.wait(lock, [this]() { return ready || killed; });
if (!killed && running) {
struct itimerspec spec{}; struct itimerspec spec{};
timer_settime(preemptionTimer, 0, &spec, nullptr); timer_settime(preemptionTimer, 0, &spec, nullptr);
isPreempted = false; isPreempted = false;