Merge #1278

1278: Fix delete crash r=Saviq a=ricab Fixes #1266. `vm_process` is a pointer now and it is null when in off state. Shutdown is called when deleting, which was dereferencing the ptr to kill the process, even if it wasn't there. Co-authored-by: Ricardo Abreu <[email protected]>
canonical · Jan 7, 2020 · 2ca8f1c · 2ca8f1c · multipass-ci-bot · Jan 7, 2020
1 parent d90f6ef
commit 2ca8f1c
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Showing 2 changed files with 18 additions and 3 deletions.
diff --git a/src/platform/backends/qemu/qemu_virtual_machine.cpp b/src/platform/backends/qemu/qemu_virtual_machine.cpp
@@ -295,8 +295,11 @@ void mp::QemuVirtualMachine::shutdown()
         if (state == State::starting)
             update_shutdown_status = false;
 
-        vm_process->kill();
-        vm_process->wait_for_finished();
+        if (vm_process)
+        {
+            vm_process->kill();
+            vm_process->wait_for_finished();
+        }
     }
 }
 
@@ -390,7 +393,7 @@ void mp::QemuVirtualMachine::on_restart()
 void mp::QemuVirtualMachine::ensure_vm_is_running()
 {
     std::lock_guard<decltype(state_mutex)> lock{state_mutex};
-    if (!vm_process->running())
+    if (!vm_process || !vm_process->running())
     {
         // Have to set 'off' here so there is an actual state change to compare to for
         // the cond var's predicate

diff --git a/tests/qemu/test_qemu_backend.cpp b/tests/qemu/test_qemu_backend.cpp
@@ -87,6 +87,18 @@ TEST_F(QemuBackend, creates_in_off_state)
     EXPECT_THAT(machine->current_state(), Eq(mp::VirtualMachine::State::off));
 }
 
+TEST_F(QemuBackend, machine_in_off_state_handles_shutdown)
+{
+    mpt::StubVMStatusMonitor stub_monitor;
+    mp::QemuVirtualMachineFactory backend{data_dir.path()};
+
+    auto machine = backend.create_virtual_machine(default_description, stub_monitor);
+    EXPECT_THAT(machine->current_state(), Eq(mp::VirtualMachine::State::off));
+
+    machine->shutdown();
+    EXPECT_THAT(machine->current_state(), Eq(mp::VirtualMachine::State::off));
+}
+
 TEST_F(QemuBackend, machine_start_shutdown_sends_monitoring_events)
 {
     NiceMock<mpt::MockVMStatusMonitor> mock_monitor;