From 8681e4ab8a2d4c95abd34abf0e0eed3351d11bf0 Mon Sep 17 00:00:00 2001 From: Simon Ser Date: Sat, 30 Nov 2019 11:57:37 +0100 Subject: [PATCH] backend/drm, backend/libinput: listen to session destroy This fixes a heap-use-after-free when the session is destroyed before the backend during wl_display_destroy: ==1085==ERROR: AddressSanitizer: heap-use-after-free on address 0x614000000180 at pc 0x7f88e3590c2d bp 0x7ffdc4e33f90 sp 0x7ffdc4e33f80 READ of size 8 at 0x614000000180 thread T0 #0 0x7f88e3590c2c in find_device ../subprojects/wlroots/backend/session/session.c:192 #1 0x7f88e3590e85 in wlr_session_close_file ../subprojects/wlroots/backend/session/session.c:204 #2 0x7f88e357b80c in libinput_close_restricted ../subprojects/wlroots/backend/libinput/backend.c:24 #3 0x7f88e21af274 (/lib64/libinput.so.10+0x28274) #4 0x7f88e21aff1d (/lib64/libinput.so.10+0x28f1d) #5 0x7f88e219ddac (/lib64/libinput.so.10+0x16dac) #6 0x7f88e21b415d in libinput_unref (/lib64/libinput.so.10+0x2d15d) #7 0x7f88e357c9d6 in backend_destroy ../subprojects/wlroots/backend/libinput/backend.c:130 #8 0x7f88e3545a09 in wlr_backend_destroy ../subprojects/wlroots/backend/backend.c:50 #9 0x7f88e358981a in multi_backend_destroy ../subprojects/wlroots/backend/multi/backend.c:54 #10 0x7f88e358a059 in handle_display_destroy ../subprojects/wlroots/backend/multi/backend.c:107 #11 0x7f88e314acde (/lib64/libwayland-server.so.0+0x8cde) #12 0x7f88e314b466 in wl_display_destroy (/lib64/libwayland-server.so.0+0x9466) #13 0x559fefb52385 in main ../main.c:67 #14 0x7f88e2639152 in __libc_start_main (/lib64/libc.so.6+0x27152) #15 0x559fefb4297d in _start (/home/simon/src/glider/build/glider+0x2297d) 0x614000000180 is located 320 bytes inside of 416-byte region [0x614000000040,0x6140000001e0) freed by thread T0 here: #0 0x7f88e3d0a6b0 in __interceptor_free /build/gcc/src/gcc/libsanitizer/asan/asan_malloc_linux.cc:122 #1 0x7f88e35b51fb in logind_session_destroy ../subprojects/wlroots/backend/session/logind.c:270 #2 0x7f88e35905a4 in wlr_session_destroy ../subprojects/wlroots/backend/session/session.c:156 #3 0x7f88e358f440 in handle_display_destroy ../subprojects/wlroots/backend/session/session.c:65 #4 0x7f88e314acde (/lib64/libwayland-server.so.0+0x8cde) previously allocated by thread T0 here: #0 0x7f88e3d0acd8 in __interceptor_calloc /build/gcc/src/gcc/libsanitizer/asan/asan_malloc_linux.cc:153 #1 0x7f88e35b911c in logind_session_create ../subprojects/wlroots/backend/session/logind.c:746 #2 0x7f88e358f6b4 in wlr_session_create ../subprojects/wlroots/backend/session/session.c:91 #3 0x559fefb51ea6 in main ../main.c:20 #4 0x7f88e2639152 in __libc_start_main (/lib64/libc.so.6+0x27152) --- backend/drm/backend.c | 10 ++++++++++ backend/libinput/backend.c | 10 ++++++++++ include/backend/drm/drm.h | 1 + include/backend/libinput.h | 1 + 4 files changed, 22 insertions(+) diff --git a/backend/drm/backend.c b/backend/drm/backend.c index 541e720f..8a10a51e 100644 --- a/backend/drm/backend.c +++ b/backend/drm/backend.c @@ -44,6 +44,7 @@ static void backend_destroy(struct wlr_backend *backend) { wlr_signal_emit_safe(&backend->events.destroy, backend); wl_list_remove(&drm->display_destroy.link); + wl_list_remove(&drm->session_destroy.link); wl_list_remove(&drm->session_signal.link); wl_list_remove(&drm->drm_invalidated.link); @@ -135,6 +136,12 @@ static void drm_invalidated(struct wl_listener *listener, void *data) { scan_drm_connectors(drm); } +static void handle_session_destroy(struct wl_listener *listener, void *data) { + struct wlr_drm_backend *drm = + wl_container_of(listener, drm, session_destroy); + backend_destroy(&drm->backend); +} + static void handle_display_destroy(struct wl_listener *listener, void *data) { struct wlr_drm_backend *drm = wl_container_of(listener, drm, display_destroy); @@ -197,6 +204,9 @@ struct wlr_backend *wlr_drm_backend_create(struct wl_display *display, goto error_event; } + drm->session_destroy.notify = handle_session_destroy; + wl_signal_add(&session->events.destroy, &drm->session_destroy); + drm->display_destroy.notify = handle_display_destroy; wl_display_add_destroy_listener(display, &drm->display_destroy); diff --git a/backend/libinput/backend.c b/backend/libinput/backend.c index 8106af00..87497b11 100644 --- a/backend/libinput/backend.c +++ b/backend/libinput/backend.c @@ -121,6 +121,7 @@ static void backend_destroy(struct wlr_backend *wlr_backend) { wlr_signal_emit_safe(&wlr_backend->events.destroy, wlr_backend); wl_list_remove(&backend->display_destroy.link); + wl_list_remove(&backend->session_destroy.link); wl_list_remove(&backend->session_signal.link); wlr_list_finish(&backend->wlr_device_lists); @@ -156,6 +157,12 @@ static void session_signal(struct wl_listener *listener, void *data) { } } +static void handle_session_destroy(struct wl_listener *listener, void *data) { + struct wlr_libinput_backend *backend = + wl_container_of(listener, backend, session_destroy); + backend_destroy(&backend->backend); +} + static void handle_display_destroy(struct wl_listener *listener, void *data) { struct wlr_libinput_backend *backend = wl_container_of(listener, backend, display_destroy); @@ -183,6 +190,9 @@ struct wlr_backend *wlr_libinput_backend_create(struct wl_display *display, backend->session_signal.notify = session_signal; wl_signal_add(&session->session_signal, &backend->session_signal); + backend->session_destroy.notify = handle_session_destroy; + wl_signal_add(&session->events.destroy, &backend->session_destroy); + backend->display_destroy.notify = handle_display_destroy; wl_display_add_destroy_listener(display, &backend->display_destroy); diff --git a/include/backend/drm/drm.h b/include/backend/drm/drm.h index 62ade510..5de4a7d1 100644 --- a/include/backend/drm/drm.h +++ b/include/backend/drm/drm.h @@ -82,6 +82,7 @@ struct wlr_drm_backend { struct wl_event_source *drm_event; struct wl_listener display_destroy; + struct wl_listener session_destroy; struct wl_listener session_signal; struct wl_listener drm_invalidated; diff --git a/include/backend/libinput.h b/include/backend/libinput.h index ddb81a5a..3e0b425c 100644 --- a/include/backend/libinput.h +++ b/include/backend/libinput.h @@ -19,6 +19,7 @@ struct wlr_libinput_backend { struct wl_event_source *input_event; struct wl_listener display_destroy; + struct wl_listener session_destroy; struct wl_listener session_signal; struct wlr_list wlr_device_lists; // list of struct wl_list