Segfault when config file is missing

[sertonix]

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• Sway Version: 1.10.1 (also happens on master branch when I apply Fix crashes on exit caused by wlroots listener checks #8578)

• Debug Log: (I really don't think the full logs are of use here)

00:00:00.051 [wlr] [backend/headless/backend.c:60] Creating headless backend
00:00:00.051 [sway/config.c:460] missing not found
00:00:00.051 [sway/main.c:377] Shutting down sway
Segmentation fault

• Configuration File: It's missing...

• Stack Trace:

(gdb) bt full
#0  0x000055555557840c in handle_seat_destroy (listener=0x7fffe81dca18, data=0x7fffe80e93d0) at ../sway/input/seat.c:76
        seat = 0x7fffe81dc7f0
        seat_device = <optimized out>
        next = <optimized out>
        seat_node = <optimized out>
        next_seat_node = <optimized out>
#1  0x00007ffff79dd827 in wl_signal_emit_mutable () at /usr/lib/libwayland-server.so.0
#2  0x00007ffff7ee4400 in wlr_seat_destroy (seat=0x7fffe80e93d0) at ../subprojects/wlroots/types/seat/wlr_seat.c:231
        point = <optimized out>
        client = <optimized out>
        tmp = <optimized out>
        point = <optimized out>
        __func__ = {<optimized out> <repeats 17 times>}
        client = <optimized out>
        tmp = <optimized out>
#3  wlr_seat_destroy (seat=0x7fffe80e93d0) at ../subprojects/wlroots/types/seat/wlr_seat.c:216
        point = <optimized out>
        client = <optimized out>
        tmp = <optimized out>
        __func__ = "wlr_seat_destroy"
#4  0x00007ffff79deac3 in ??? () at /usr/lib/libwayland-server.so.0
#5  0x00007ffff79df2da in wl_display_destroy () at /usr/lib/libwayland-server.so.0
#6  0x0000555555563cee in server_fini (server=0x5555555c0160 <server>) at ../sway/server.c:489
#7  main (argc=<optimized out>, argv=<optimized out>) at ../sway/main.c:379
        config_path = 0x7ffff78703c0 "missing"
        c = <optimized out>
        validate = false
        debug = false
        verbose = false

• Description:

Just running sway --config missing (when missing doesn't exit) is enough to trigger the segfault.

In handle_seat_destroy config is dereferenced but config is NULL when the config file couldn't be found.

sway/sway/input/seat.c

Line 76 in 10e50e6

if (seat == config->handler_context.seat) {

config is only initialized later in the code:

sway/sway/config.c

Line 466 in 10e50e6

config = calloc(1, sizeof(struct sway_config));