Segfault in XrmDestroyDatabase in dunst 1.9.2

[fwsmit]

Discussed in #1256

^{Originally posted by cdown April 28, 2023}
Didn't debug further yet since I'm going to be away for a bit, but I figure you'd like to know:

(gdb) bt
#0  ___pthread_mutex_lock (mutex=0x0) at pthread_mutex_lock.c:80
#1  0x00007f292eeb1733 in XrmDestroyDatabase (db=0x7f2918003860) at /usr/src/debug/libx11/libX11-1.8.4/src/Xrm.c:2653
#2  0x00007f292eeab8c6 in XrmSetDatabase (display=0x5560554e43c0, database=0x5560555675c0) at /usr/src/debug/libx11/libX11-1.8.4/src/Xrm.c:354
#3  0x00005560546707b1 in XRM_update_db () at src/x11/x.c:493
#4  0x0000556054670c38 in x_mainloop_fd_dispatch (source=<optimized out>, callback=<optimized out>, user_data=<optimized out>) at src/x11/x.c:354
#5  0x00007f292eac853b in g_main_dispatch (context=0x5560554c90d0) at ../glib/glib/gmain.c:3460
#6  g_main_context_dispatch (context=0x5560554c90d0) at ../glib/glib/gmain.c:4200
#7  0x00007f292eb25219 in g_main_context_iterate.constprop.0 (context=0x5560554c90d0, block=1, dispatch=1, self=<optimized out>) at ../glib/glib/gmain.c:4276
#8  0x00007f292eac7c7f in g_main_loop_run (loop=0x5560554d4820) at ../glib/glib/gmain.c:4479
#9  0x000055605466063d in dunst_main (argv=<optimized out>, argc=<optimized out>) at src/dunst.c:227
#10 main (argc=<optimized out>, argv=<optimized out>) at /usr/src/debug/dunst/dunst-1.9.2/main.c:5

So somehow ___pthread_mutex_lock is getting NULL.

This only happens immediately after starting X/wm/etc, so my guess is something is racing.

[bynect]

This is an interesting issue, maybe it has to do with the way the xrm database is first initialized with the static variable? I'll try looking into it

[bynect]

Fixed in #1291