The new revision also fixes it, thank you for the quick response.
On Tue, Aug 04, 2020 at 09:51:24AM +0100, Nicholas Marriott wrote:
> I made it just ignore SIGQUIT entirely, there is no reason it needs to
> do anything. Please try now with proc.c r1.18.
>
> Thanks!
>
>
> On Mon, Aug 03, 2020 at 11:33:29PM +0000, Eldritch wrote:
> > >Synopsis: Locked tmux session can be escaped from by using ctrl+\
> > >Category: user
> > >Environment:
> > System : OpenBSD 6.7
> > Details : OpenBSD 6.7-current (GENERIC.MP) #1: Mon Aug 3 14:30:52
> > MDT 2020
> >
> > [email protected]:/usr/src/sys/arch/amd64/compile/GENERIC.MP
> >
> > Architecture: OpenBSD.amd64
> > Machine : amd64
> > >Description:
> > After pressing ^\ inside a locked tmux session, tmux dumps core
> > but doesn't exit, instead detaching from the terminal. After
> > reattaching, the session will not be locked anymore.
> >
> > If using the default "lock-command" which is lock(1), shortly
> > afterwards the screen will be flooded with lock(1)'s prompts,
> > but you can enter commands in the parent shell and kill the
> > lock process.
> >
> > When ran normally (even inside tmux), lock(1) ignores the
> > SIGQUIT from ^\, therefore this bug only affects tmux's
> > "locked" state. I tested this with an empty ~/.tmux.conf.
> >
> > Also reproduced on OpenBSD-stable 6.7 (GENERIC.MP) #5 amd64, and
> > tmux 3.1b on Linux.
> >
> > gdb(1) backtrace of the tmux core dump (on -current):
> >
> > #0 _thread_sys_wait4 () at /tmp/-:3
> > #1 0x000006a794ac582e in _libc_wait4_cancel (wpid=Variable "wpid" is
> > not available.) at /usr/src/lib/libc/sys/w_wait4.c:27
> > #2 0x000006a794b2e00d in _libc_system (command=Variable "command" is
> > not available.) at /usr/src/lib/libc/stdlib/system.c:69
> > #3 0x000006a4caac7a00 in client_dispatch_attached
> > (imsg=0x7f7ffffd3c70) at client.c:1006
> > #4 0x000006a4caac7270 in client_dispatch (imsg=0x7f7ffffd3c70,
> > arg=0x0) at client.c:807
> > #5 0x000006a4cab1dc66 in proc_event_cb (fd=6, events=2,
> > arg=0x6a7ac809000) at proc.c:95
> > #6 0x000006a75cf3f0cf in event_base_loop (base=0x6a7a516a000,
> > flags=Variable "flags" is not available.) at
> > /usr/src/lib/libevent/event.c:333
> > #7 0x000006a4cab1e093 in proc_loop (tp=0x6a775441000, loopcb=0) at
> > proc.c:202
> > #8 0x000006a4caac6130 in client_main (base=0x6a7a516a000, argc=0,
> > argv=0x7f7ffffd3f90, flags=402718720, feat=0) at client.c:385
> > #9 0x000006a4cab3ec48 in main (argc=0, argv=0x7f7ffffd3f90) at
> > tmux.c:502
> >
> > >How-To-Repeat:
> > 1. Launch tmux
> > 2. Lock the tmux session using ctrl+b :lock
> > 3. Press ctrl+\
> > 4. Blindly run "pkill lock" to stop the flood of text
> > >Fix:
> > The following patch seems to fix it. The server correctly shuts
> > down if it receives a SIGQUIT while not locked, or after lock(1)
> > exits if it was locked when the signal arrived, the latter being
> > the same behavior as other terminating signals.
> >
> > Index: proc.c
> > ===================================================================
> > RCS file: /cvs/src/usr.bin/tmux/proc.c,v
> > retrieving revision 1.17
> > diff -u -p -r1.17 proc.c
> > --- proc.c 16 May 2020 16:07:55 -0000 1.17
> > +++ proc.c 3 Aug 2020 22:15:46 -0000
> > @@ -42,6 +42,7 @@ struct tmuxproc {
> > struct event ev_sigchld;
> > struct event ev_sigcont;
> > struct event ev_sigterm;
> > + struct event ev_sigquit;
> > struct event ev_sigusr1;
> > struct event ev_sigusr2;
> > struct event ev_sigwinch;
> > @@ -237,6 +238,8 @@ proc_set_signals(struct tmuxproc *tp, vo
> > signal_add(&tp->ev_sigcont, NULL);
> > signal_set(&tp->ev_sigterm, SIGTERM, proc_signal_cb, tp);
> > signal_add(&tp->ev_sigterm, NULL);
> > + signal_set(&tp->ev_sigquit, SIGQUIT, proc_signal_cb, tp);
> > + signal_add(&tp->ev_sigquit, NULL);
> > signal_set(&tp->ev_sigusr1, SIGUSR1, proc_signal_cb, tp);
> > signal_add(&tp->ev_sigusr1, NULL);
> > signal_set(&tp->ev_sigusr2, SIGUSR2, proc_signal_cb, tp);
> > Index: server.c
> > ===================================================================
> > RCS file: /cvs/src/usr.bin/tmux/server.c,v
> > retrieving revision 1.194
> > diff -u -p -r1.194 server.c
> > --- server.c 18 Jun 2020 08:34:22 -0000 1.194
> > +++ server.c 3 Aug 2020 22:15:46 -0000
> > @@ -407,6 +407,7 @@ server_signal(int sig)
> > switch (sig) {
> > case SIGINT:
> > case SIGTERM:
> > + case SIGQUIT:
> > server_exit = 1;
> > server_send_exit();
> > break;
> >
