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Simon Ser 7915a2ff59 tinywl: fix wlr_seat use-after-free on exit
When pressing the keybinding to shut down the compositor, the following
use-after-free is triggered:

    ==1165966==ERROR: AddressSanitizer: heap-use-after-free on address 0x51800000ade0 at pc 0x7fa6728b4531 bp 0x7ffe540a6aa0 sp 0x7ffe540a6a90
    READ of size 8 at 0x51800000ade0 thread T0
        #0 0x7fa6728b4530 in wlr_seat_set_keyboard ../types/seat/wlr_seat_keyboard.c:124
        #1 0x58a83fa7fd4e in keyboard_handle_key ../tinywl/tinywl.c:228
        #2 0x7fa673a1901d in wl_signal_emit_mutable (/usr/lib/libwayland-server.so.0+0xa01d) (BuildId: d943a6a6069d1b5293dad7c842d26ce407ebdd19)
        #3 0x7fa67295b4be in wlr_keyboard_notify_key ../types/wlr_keyboard.c:102
        #4 0x7fa67295c791 in wlr_keyboard_finish ../types/wlr_keyboard.c:165
        #5 0x7fa672848cb1 in destroy_wl_seat ../backend/wayland/seat.c:293
        #6 0x7fa672833dca in backend_destroy ../backend/wayland/backend.c:493
        #7 0x7fa6727b49e8 in wlr_backend_destroy ../backend/backend.c:67
        #8 0x7fa67282d334 in multi_backend_destroy ../backend/multi/backend.c:59
        #9 0x7fa67282da5a in handle_event_loop_destroy ../backend/multi/backend.c:110
        #10 0x7fa673a18b98 in wl_event_loop_destroy (/usr/lib/libwayland-server.so.0+0x9b98) (BuildId: d943a6a6069d1b5293dad7c842d26ce407ebdd19)
        #11 0x7fa673a1b43c in wl_display_destroy (/usr/lib/libwayland-server.so.0+0xc43c) (BuildId: d943a6a6069d1b5293dad7c842d26ce407ebdd19)
        #12 0x58a83fa8ada1 in main ../tinywl/tinywl.c:1068
        #13 0x7fa672043ccf  (/usr/lib/libc.so.6+0x25ccf) (BuildId: c0caa0b7709d3369ee575fcd7d7d0b0fc48733af)
        #14 0x7fa672043d89 in __libc_start_main (/usr/lib/libc.so.6+0x25d89) (BuildId: c0caa0b7709d3369ee575fcd7d7d0b0fc48733af)
        #15 0x58a83fa7e7c4 in _start (/home/simon/src/wlroots/build/tinywl/tinywl+0x167c4) (BuildId: 1febf2a5a18bda0f6b67377a132484061875e248)

    0x51800000ade0 is located 352 bytes inside of 880-byte region [0x51800000ac80,0x51800000aff0)
    freed by thread T0 here:
        #0 0x7fa6732dfdb2 in __interceptor_free /usr/src/debug/gcc/gcc/libsanitizer/asan/asan_malloc_linux.cpp:52
        #1 0x7fa6728c6a1e in wlr_seat_destroy ../types/seat/wlr_seat.c:245
        #2 0x7fa6728c6a7a in handle_display_destroy ../types/seat/wlr_seat.c:251
        #3 0x7fa673a1b3c6 in wl_display_destroy (/usr/lib/libwayland-server.so.0+0xc3c6) (BuildId: d943a6a6069d1b5293dad7c842d26ce407ebdd19)

    previously allocated by thread T0 here:
        #0 0x7fa6732e0cc1 in __interceptor_calloc /usr/src/debug/gcc/gcc/libsanitizer/asan/asan_malloc_linux.cpp:77
        #1 0x7fa6728c6a9d in wlr_seat_create ../types/seat/wlr_seat.c:255
        #2 0x58a83fa8a8d3 in main ../tinywl/tinywl.c:1024
        #3 0x7fa672043ccf  (/usr/lib/libc.so.6+0x25ccf) (BuildId: c0caa0b7709d3369ee575fcd7d7d0b0fc48733af)

This happens because the wlr_seat is destroyed before the
wlr_keyboard. Destroying the wlr_keyboard has the side effect of
implicitly releasing keys currently held down.

Explicitly destroying the wlr_backend before the wl_display fixes
this.

Suggested-by: Isaac Freund <ifreund@ifreund.xyz>
2024-03-04 12:50:14 +00:00
.builds ci: drop stale dependencies 2023-12-10 14:29:23 +01:00
.gitlab/issue_templates Add GitLab issue template 2023-10-08 11:29:13 +00:00
backend backend/drm: track cursor FB in wlr_drm_connector_state 2024-03-04 11:26:20 +01:00
docs docs: add architecture document 2023-10-10 09:50:57 +00:00
examples input-device: unconfuse tablet naming 2024-02-29 16:09:07 +01:00
include backend/drm: track cursor FB in wlr_drm_connector_state 2024-03-04 11:26:20 +01:00
protocol ext-foreign-toplevel-list-v1: new protocol implementation 2024-02-12 01:05:19 +01:00
render render/egl: drop wlr_egl_is_current() 2024-02-23 18:52:48 +01:00
tinywl tinywl: fix wlr_seat use-after-free on exit 2024-03-04 12:50:14 +00:00
types wlr_tablet_v2: fix destroy listener name 2024-02-29 16:09:08 +01:00
util Define _POSIX_C_SOURCE globally 2024-02-15 15:41:12 +01:00
xcursor Define _POSIX_C_SOURCE globally 2024-02-15 15:41:12 +01:00
xwayland xwayland: add map_request signal 2024-02-23 12:46:25 -05:00
.editorconfig Relax 80 column limit 2022-11-22 18:19:46 +00:00
.gitignore gitignore: remove build dir entries 2022-06-14 10:08:54 +02:00
.gitlab-ci.yml ci: add .gitlab-ci.yml 2021-11-01 16:51:18 +01:00
CONTRIBUTING.md contributing: add safety section 2023-10-04 11:08:58 +02:00
LICENSE license: add copyright line for all contributors 2023-07-05 10:27:50 +02:00
README.md backend/drm: use libdisplay-info to parse EDID 2023-02-28 14:44:02 +00:00
meson.build Define _POSIX_C_SOURCE globally 2024-02-15 15:41:12 +01:00
meson_options.txt backend/session: make optional 2022-11-25 16:15:29 +00:00
wlroots.syms build: simplify version script 2021-06-17 11:03:21 +02:00

README.md

wlroots

Pluggable, composable, unopinionated modules for building a Wayland compositor; or about 60,000 lines of code you were going to write anyway.

  • wlroots provides backends that abstract the underlying display and input hardware, including KMS/DRM, libinput, Wayland, X11, and headless backends, plus any custom backends you choose to write, which can all be created or destroyed at runtime and used in concert with each other.
  • wlroots provides unopinionated, mostly standalone implementations of many Wayland interfaces, both from wayland.xml and various protocol extensions. We also promote the standardization of portable extensions across many compositors.
  • wlroots provides several powerful, standalone, and optional tools that implement components common to many compositors, such as the arrangement of outputs in physical space.
  • wlroots provides an Xwayland abstraction that allows you to have excellent Xwayland support without worrying about writing your own X11 window manager on top of writing your compositor.
  • wlroots provides a renderer abstraction that simple compositors can use to avoid writing GL code directly, but which steps out of the way when your needs demand custom rendering code.

wlroots implements a huge variety of Wayland compositor features and implements them right, so you can focus on the features that make your compositor unique. By using wlroots, you get high performance, excellent hardware compatibility, broad support for many wayland interfaces, and comfortable development tools - or any subset of these features you like, because all of them work independently of one another and freely compose with anything you want to implement yourself.

Check out our wiki to get started with wlroots. Join our IRC channel: #wlroots on Libera Chat.

A variety of wrapper libraries are available for using it with your favorite programming language.

Building

Install dependencies:

  • meson
  • wayland
  • wayland-protocols
  • EGL and GLESv2 (optional, for the GLES2 renderer)
  • Vulkan loader, headers and glslang (optional, for the Vulkan renderer)
  • libdrm
  • GBM (optional, for the GBM allocator)
  • libinput (optional, for the libinput backend)
  • xkbcommon
  • udev (optional, for the session)
  • pixman
  • libseat (optional, for the session)
  • hwdata (optional, for the DRM backend)
  • libdisplay-info (optional, for the DRM backend)
  • libliftoff (optional, for the DRM backend)

If you choose to enable X11 support:

  • xwayland (build-time only, optional at runtime)
  • libxcb
  • libxcb-render-util
  • libxcb-wm
  • libxcb-errors (optional, for improved error reporting)

Run these commands:

meson setup build/
ninja -C build/

Install like so:

sudo ninja -C build/ install

Contributing

See CONTRIBUTING.md.