From d5e14ab2470032a5f8152c685415724a4734b492 Mon Sep 17 00:00:00 2001 From: Dominique Martinet Date: Sat, 17 Mar 2018 17:11:43 +0100 Subject: [PATCH] wayland backend: fix use-after free on output destroy ==12021==ERROR: AddressSanitizer: heap-use-after-free on address 0x617000015698 at pc 0x7f1a9abe1c09 bp 0x7ffe9068f6b0 sp 0x7ffe9068f6a0 WRITE of size 4 at 0x617000015698 thread T0 #0 0x7f1a9abe1c08 in pointer_handle_leave ../backend/wayland/wl_seat.c:40 #1 0x7f1a96ae7d1d in ffi_call_unix64 (/lib64/libffi.so.6+0x5d1d) #2 0x7f1a96ae768e in ffi_call (/lib64/libffi.so.6+0x568e) #3 0x7f1a988e0d8a (/lib64/libwayland-client.so.0+0x8d8a) #4 0x7f1a988dd927 (/lib64/libwayland-client.so.0+0x5927) #5 0x7f1a988debe3 in wl_display_dispatch_queue_pending (/lib64/libwayland-client.so.0+0x6be3) #6 0x7f1a9abdd6d6 in dispatch_events ../backend/wayland/backend.c:28 #7 0x7f1a9a968c11 in wl_event_loop_dispatch (/lib64/libwayland-server.so.0+0x9c11) #8 0x7f1a9a967449 in wl_display_run (/lib64/libwayland-server.so.0+0x8449) #9 0x418dff in main ../rootston/main.c:81 #10 0x7f1a99b5ef29 in __libc_start_main (/lib64/libc.so.6+0x20f29) #11 0x4057c9 in _start (/home/shared/wayland/wlroots/build/rootston/rootston+0x4057c9) 0x617000015698 is located 664 bytes inside of 696-byte region [0x617000015400,0x6170000156b8) freed by thread T0 here: #0 0x7f1a9af754b8 in __interceptor_free (/lib64/libasan.so.4+0xde4b8) #1 0x7f1a9abe01ee in wlr_wl_output_destroy ../backend/wayland/output.c:194 #2 0x7f1a9ac12918 in wlr_output_destroy ../types/wlr_output.c:299 #3 0x7f1a9abe061b in xdg_toplevel_handle_close ../backend/wayland/output.c:255 #4 0x7f1a96ae7d1d in ffi_call_unix64 (/lib64/libffi.so.6+0x5d1d) #5 0x7f1a96ae768e in ffi_call (/lib64/libffi.so.6+0x568e) #6 0x7f1a988e0d8a (/lib64/libwayland-client.so.0+0x8d8a) #7 0x7f1a988dd927 (/lib64/libwayland-client.so.0+0x5927) #8 0x7f1a988debe3 in wl_display_dispatch_queue_pending (/lib64/libwayland-client.so.0+0x6be3) #9 0x7f1a9abdd6d6 in dispatch_events ../backend/wayland/backend.c:28 #10 0x7f1a9a968c11 in wl_event_loop_dispatch (/lib64/libwayland-server.so.0+0x9c11) #11 0x7f1a9a967449 in wl_display_run (/lib64/libwayland-server.so.0+0x8449) #12 0x418dff in main ../rootston/main.c:81 #13 0x7f1a99b5ef29 in __libc_start_main (/lib64/libc.so.6+0x20f29) #14 0x4057c9 in _start (/home/shared/wayland/wlroots/build/rootston/rootston+0x4057c9) previously allocated by thread T0 here: #0 0x7f1a9af75a38 in __interceptor_calloc (/lib64/libasan.so.4+0xdea38) #1 0x7f1a9abe0703 in wlr_wl_output_create ../backend/wayland/output.c:272 #2 0x7f1a9abdd8eb in wlr_wl_backend_start ../backend/wayland/backend.c:55 #3 0x7f1a9abbeb49 in wlr_backend_start ../backend/backend.c:28 #4 0x7f1a9abd8ce1 in multi_backend_start ../backend/multi/backend.c:24 #5 0x7f1a9abbeb49 in wlr_backend_start ../backend/backend.c:28 #6 0x418c32 in main ../rootston/main.c:58 #7 0x7f1a99b5ef29 in __libc_start_main (/lib64/libc.so.6+0x20f29) #8 0x4057c9 in _start (/home/shared/wayland/wlroots/build/rootston/rootston+0x4057c9) --- backend/wayland/wl_seat.c | 17 ++++++++++++++++- include/backend/wayland.h | 1 + 2 files changed, 17 insertions(+), 1 deletion(-) diff --git a/backend/wayland/wl_seat.c b/backend/wayland/wl_seat.c index 841e693d..6ca59130 100644 --- a/backend/wayland/wl_seat.c +++ b/backend/wayland/wl_seat.c @@ -26,6 +26,11 @@ static void pointer_handle_enter(void *data, struct wl_pointer *wl_pointer, // GNOME sends a pointer enter when the surface is being destroyed return; } + if (wlr_wl_pointer->current_output) { + wl_list_remove(&wlr_wl_pointer->output_destroy_listener.link); + } + wl_signal_add(&output->wlr_output.events.destroy, + &wlr_wl_pointer->output_destroy_listener); wlr_wl_pointer->current_output = output; output->enter_serial = serial; wlr_wl_output_update_cursor(output); @@ -49,7 +54,7 @@ static void pointer_handle_motion(void *data, struct wl_pointer *wl_pointer, struct wlr_wl_pointer *wlr_wl_pointer = (struct wlr_wl_pointer *)dev->pointer; if (!wlr_wl_pointer->current_output) { - wlr_log(L_ERROR, "pointer motion event without current output"); + wlr_log(L_DEBUG, "pointer motion event without current output"); return; } @@ -231,6 +236,14 @@ static struct wlr_input_device *allocate_device(struct wlr_wl_backend *backend, return wlr_device; } +static void wlr_wl_pointer_handle_output_destroy(struct wl_listener *listener, + void *data) { + struct wlr_wl_pointer *wlr_wl_pointer = + wl_container_of(listener, wlr_wl_pointer, output_destroy_listener); + wlr_wl_pointer->current_output = NULL; + wl_list_remove(&wlr_wl_pointer->output_destroy_listener.link); +} + static void seat_handle_capabilities(void *data, struct wl_seat *wl_seat, enum wl_seat_capability caps) { struct wlr_wl_backend *backend = data; @@ -243,6 +256,8 @@ static void seat_handle_capabilities(void *data, struct wl_seat *wl_seat, wlr_log(L_ERROR, "Unable to allocate wlr_wl_pointer"); return; } + wlr_wl_pointer->output_destroy_listener.notify = + wlr_wl_pointer_handle_output_destroy; struct wlr_input_device *wlr_device; if (!(wlr_device = allocate_device(backend, WLR_INPUT_DEVICE_POINTER))) { diff --git a/include/backend/wayland.h b/include/backend/wayland.h index b68208af..00b6ae89 100644 --- a/include/backend/wayland.h +++ b/include/backend/wayland.h @@ -71,6 +71,7 @@ struct wlr_wl_pointer { struct wlr_pointer wlr_pointer; enum wlr_axis_source axis_source; struct wlr_wl_backend_output *current_output; + struct wl_listener output_destroy_listener; }; void wlr_wl_registry_poll(struct wlr_wl_backend *backend);