commit 52939b686ae906897e9b7956b61d15c255539e6d
from: Stefan Sperling <stsp@stsp.name>
via: Thomas Adam <thomas@xteddy.org>
date: Fri Feb 17 16:23:18 2023 UTC

fix gotd segfault in libevent while disconnecting clients

Sending a DISCONNECT message to the repo process and then killing
it and freeing its structure won't work. The message ends up on
internal libevent queues and will soon crash because we have freed
the memory for the event structre.
Sending that message is a leftover from the times when the repo
procs were persistent.

commit - 43c08a530e595df40d8133b9a3f77318c2a04b44
commit + 52939b686ae906897e9b7956b61d15c255539e6d
blob - 36ce2515faf1ac5c49de622315565ce78955f76b
blob + 00d1d81a42f9598ad0cba57a03f07fb868556714
--- gotd/gotd.c
+++ gotd/gotd.c
@@ -338,13 +338,8 @@ disconnect(struct gotd_client *client)
 	kill_auth_proc(client);
 	kill_session_proc(client);
 
-	idisconnect.client_id = client->id;
 	if (proc) {
-		if (gotd_imsg_compose_event(&proc->iev,
-		    GOTD_IMSG_DISCONNECT, PROC_GOTD, -1,
-		    &idisconnect, sizeof(idisconnect)) == -1)
-			log_warn("imsg compose DISCONNECT");
-
+		event_del(&proc->iev.ev);
 		msgbuf_clear(&proc->iev.ibuf.w);
 		close(proc->iev.ibuf.fd);
 		kill_proc(proc, 0);
@@ -353,6 +348,7 @@ disconnect(struct gotd_client *client)
 		proc = NULL;
 	}
 
+	idisconnect.client_id = client->id;
 	if (gotd_imsg_compose_event(&listen_proc->iev,
 	    GOTD_IMSG_DISCONNECT, PROC_GOTD, -1,
 	    &idisconnect, sizeof(idisconnect)) == -1)