From 05ce8586ea257a54717a67fbe20e9dff15a9b0c2 Mon Sep 17 00:00:00 2001 From: Cristian-Bogdan SIRB Date: Thu, 27 Feb 2020 08:40:40 +0200 Subject: [PATCH] Kernel: Fix ASSERTION failed in join_thread syscall set_interrupted_by_death was never called whenever a thread that had a joiner died, so the joiner remained with the joinee pointer there, resulting in an assertion fail in JoinBlocker: m_joinee pointed to a freed task, filled with garbage. Thread::current->m_joinee may not be valid after the unblock Properly return the joinee exit value to the joiner thread. --- Kernel/Process.cpp | 12 ++++++++---- Kernel/Thread.cpp | 1 + 2 files changed, 9 insertions(+), 4 deletions(-) diff --git a/Kernel/Process.cpp b/Kernel/Process.cpp index 683c71f582..777dff2211 100644 --- a/Kernel/Process.cpp +++ b/Kernel/Process.cpp @@ -3844,10 +3844,14 @@ int Process::sys$join_thread(int tid, void** exit_value) if (result == Thread::BlockResult::InterruptedByDeath) { // NOTE: This cleans things up so that Thread::finalize() won't // get confused about a missing joiner when finalizing the joinee. - InterruptDisabler disabler; - Thread::current->m_joinee->m_joiner = nullptr; - Thread::current->m_joinee = nullptr; - return 0; + InterruptDisabler disabler_t; + + if (Thread::current->m_joinee) { + Thread::current->m_joinee->m_joiner = nullptr; + Thread::current->m_joinee = nullptr; + } + + break; } } diff --git a/Kernel/Thread.cpp b/Kernel/Thread.cpp index cb20b00083..4502cd569a 100644 --- a/Kernel/Thread.cpp +++ b/Kernel/Thread.cpp @@ -300,6 +300,7 @@ void Thread::finalize() if (m_joiner) { ASSERT(m_joiner->m_joinee == this); static_cast(m_joiner->m_blocker)->set_joinee_exit_value(m_exit_value); + static_cast(m_joiner->m_blocker)->set_interrupted_by_death(); m_joiner->m_joinee = nullptr; // NOTE: We clear the joiner pointer here as well, to be tidy. m_joiner = nullptr;