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)
Simon Ser
8681e4ab8a