From 769a2616aec500df19e92c47886df3cf99b4d51d Mon Sep 17 00:00:00 2001 From: =?utf8?q?R=C3=A9mi=20Bernon?= Date: Wed, 21 Apr 2021 10:38:15 +0200 Subject: [PATCH] server: Track desktop users per thread instead of per process. MIME-Version: 1.0 Content-Type: text/plain; charset=utf8 Content-Transfer-Encoding: 8bit As some thread may use a different desktop from their process. This fixes the user32 win tests, which leaks a desktop that never gets closed. The test_shell_window test creates a new desktop, which spawns explorer.exe process, incrementing the desktop user count to 1, then associates the desktop to a thread, which closes it on exit. Never the user count is incremented to 2, and closing the thread desktop doesn't either check whether the desktop process should be terminated. Reversely, it is possible to create a desktop, associate it with a thread /and/ a process, and this time the desktop process would be terminated when the process exits, although the thread may still be using it. Tracking the users per thread is more robust and fixes the problem as set_thread_desktop increments the desktop user count, and thread exit decrements it. Signed-off-by: Rémi Bernon Signed-off-by: Alexandre Julliard --- server/process.c | 6 +++-- server/thread.c | 15 +++++++++-- server/user.h | 3 ++- server/winstation.c | 72 +++++++++++++++++++++++++++++++++-------------------- 4 files changed, 64 insertions(+), 32 deletions(-) diff --git a/server/process.c b/server/process.c index 8ad5a59a20b..d819f03a615 100644 --- a/server/process.c +++ b/server/process.c @@ -841,7 +841,7 @@ static void process_killed( struct process *process ) assert( list_empty( &process->thread_list )); process->end_time = current_time; - if (!process->is_system) close_process_desktop( process ); + close_process_desktop( process ); process->winstation = 0; process->desktop = 0; cancel_process_asyncs( process ); @@ -1503,6 +1503,7 @@ DECL_HANDLER(get_process_idle_event) DECL_HANDLER(make_process_system) { struct process *process = current->process; + struct thread *thread; if (!shutdown_event) { @@ -1515,8 +1516,9 @@ DECL_HANDLER(make_process_system) if (!process->is_system) { + LIST_FOR_EACH_ENTRY( thread, &process->thread_list, struct thread, proc_entry ) + release_thread_desktop( thread, 0 ); process->is_system = 1; - close_process_desktop( process ); if (!--user_processes && !shutdown_stage && master_socket_timeout != TIMEOUT_INFINITE) shutdown_timeout = add_timeout_user( master_socket_timeout, server_shutdown_timeout, NULL ); } diff --git a/server/thread.c b/server/thread.c index fe9f9bdec37..66f1057d1db 100644 --- a/server/thread.c +++ b/server/thread.c @@ -306,6 +306,7 @@ static struct context *create_thread_context( struct thread *thread ) /* create a new thread */ struct thread *create_thread( int fd, struct process *process, const struct security_descriptor *sd ) { + struct desktop *desktop; struct thread *thread; int request_pipe[2]; @@ -342,7 +343,7 @@ struct thread *create_thread( int fd, struct process *process, const struct secu init_thread_structure( thread ); thread->process = (struct process *)grab_object( process ); - thread->desktop = process->desktop; + thread->desktop = 0; thread->affinity = process->affinity; if (!current) current = thread; @@ -369,6 +370,16 @@ struct thread *create_thread( int fd, struct process *process, const struct secu return NULL; } + if (process->desktop) + { + if (!(desktop = get_desktop_obj( process, process->desktop, 0 ))) clear_error(); /* ignore errors */ + else + { + set_thread_default_desktop( thread, desktop, process->desktop ); + release_object( desktop ); + } + } + set_fd_events( thread->request_fd, POLLIN ); /* start listening to events */ add_process_thread( thread->process, thread ); return thread; @@ -416,7 +427,7 @@ static void cleanup_thread( struct thread *thread ) cleanup_clipboard_thread(thread); destroy_thread_windows( thread ); free_msg_queue( thread ); - close_thread_desktop( thread ); + release_thread_desktop( thread, 1 ); for (i = 0; i < MAX_INFLIGHT_FDS; i++) { if (thread->inflight[i].client != -1) diff --git a/server/user.h b/server/user.h index 6267f3e2881..80f7e91f12c 100644 --- a/server/user.h +++ b/server/user.h @@ -188,7 +188,8 @@ extern void connect_process_winstation( struct process *process, struct thread * extern void set_process_default_desktop( struct process *process, struct desktop *desktop, obj_handle_t handle ); extern void close_process_desktop( struct process *process ); -extern void close_thread_desktop( struct thread *thread ); +extern void set_thread_default_desktop( struct thread *thread, struct desktop *desktop, obj_handle_t handle ); +extern void release_thread_desktop( struct thread *thread, int close ); static inline int is_rect_empty( const rectangle_t *rect ) { diff --git a/server/winstation.c b/server/winstation.c index 1c7552f0687..61f9f77c73f 100644 --- a/server/winstation.c +++ b/server/winstation.c @@ -324,15 +324,22 @@ static void add_desktop_user( struct desktop *desktop ) /* remove a user of the desktop and start the close timeout if necessary */ static void remove_desktop_user( struct desktop *desktop ) { + struct process *process; assert( desktop->users > 0 ); desktop->users--; /* if we have one remaining user, it has to be the manager of the desktop window */ - if (desktop->users == 1 && get_top_window_owner( desktop )) - { - assert( !desktop->close_timeout ); + if ((process = get_top_window_owner( desktop )) && desktop->users == process->running_threads && !desktop->close_timeout) desktop->close_timeout = add_timeout_user( -TICKS_PER_SEC, close_desktop_timeout, desktop ); - } +} + +/* set the thread default desktop handle */ +void set_thread_default_desktop( struct thread *thread, struct desktop *desktop, obj_handle_t handle ) +{ + if (thread->desktop) return; /* nothing to do */ + + thread->desktop = handle; + if (!thread->process->is_system) add_desktop_user( desktop ); } /* set the process default desktop handle */ @@ -340,24 +347,14 @@ void set_process_default_desktop( struct process *process, struct desktop *deskt obj_handle_t handle ) { struct thread *thread; - struct desktop *old_desktop; if (process->desktop == handle) return; /* nothing to do */ - if (!(old_desktop = get_desktop_obj( process, process->desktop, 0 ))) clear_error(); process->desktop = handle; /* set desktop for threads that don't have one yet */ LIST_FOR_EACH_ENTRY( thread, &process->thread_list, struct thread, proc_entry ) - if (!thread->desktop) thread->desktop = handle; - - if (!process->is_system && desktop != old_desktop) - { - add_desktop_user( desktop ); - if (old_desktop) remove_desktop_user( old_desktop ); - } - - if (old_desktop) release_object( old_desktop ); + set_thread_default_desktop( thread, desktop, handle ); } /* connect a process to its window station */ @@ -413,23 +410,37 @@ done: /* close the desktop of a given process */ void close_process_desktop( struct process *process ) { - struct desktop *desktop; + obj_handle_t handle; - if (process->desktop && (desktop = get_desktop_obj( process, process->desktop, 0 ))) - { - remove_desktop_user( desktop ); - release_object( desktop ); - } - clear_error(); /* ignore errors */ + if (!(handle = process->desktop)) return; + + process->desktop = 0; + close_handle( process, handle ); } -/* close the desktop of a given thread */ -void close_thread_desktop( struct thread *thread ) +/* release (and eventually close) the desktop of a given thread */ +void release_thread_desktop( struct thread *thread, int close ) { - obj_handle_t handle = thread->desktop; + struct desktop *desktop; + obj_handle_t handle; + + if (!(handle = thread->desktop)) return; + + if (!thread->process->is_system) + { + if (!(desktop = get_desktop_obj( thread->process, handle, 0 ))) clear_error(); /* ignore errors */ + else + { + remove_desktop_user( desktop ); + release_object( desktop ); + } + } - thread->desktop = 0; - if (handle) close_handle( thread->process, handle ); + if (close) + { + thread->desktop = 0; + close_handle( thread->process, handle ); + } } /* create a window station */ @@ -624,7 +635,14 @@ DECL_HANDLER(set_thread_desktop) if (old_desktop != new_desktop && current->desktop_users > 0) set_error( STATUS_DEVICE_BUSY ); else + { current->desktop = req->handle; /* FIXME: should we close the old one? */ + if (!current->process->is_system && old_desktop != new_desktop) + { + add_desktop_user( new_desktop ); + if (old_desktop) remove_desktop_user( old_desktop ); + } + } if (!current->process->desktop) set_process_default_desktop( current->process, new_desktop, req->handle ); -- 2.11.4.GIT