From: yasuoka <yasuoka@openbsd.org>
Date: Sat, 23 Mar 2024 22:51:49 +0000 (+0000)
Subject: In kq_del(), delete matching EV_ADD entries to prevent libevent from
X-Git-Url: http://artulab.com/gitweb/?a=commitdiff_plain;h=a96d88d343f8e72bf9b7b2edd2b6a13466e2edb6;p=openbsd

In kq_del(), delete matching EV_ADD entries to prevent libevent from
passing both EV_ADD and EV_DELETE for the same fd to kevent().

ok visa
---

diff --git a/lib/libevent/kqueue.c b/lib/libevent/kqueue.c
index f61da384376..e076213a7b3 100644
--- a/lib/libevent/kqueue.c
+++ b/lib/libevent/kqueue.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: kqueue.c,v 1.42 2022/12/27 23:05:55 jmc Exp $	*/
+/*	$OpenBSD: kqueue.c,v 1.43 2024/03/23 22:51:49 yasuoka Exp $	*/
 
 /*
  * Copyright 2000-2002 Niels Provos <provos@citi.umich.edu>
@@ -358,6 +358,7 @@ kq_add(void *arg, struct event *ev)
 static int
 kq_del(void *arg, struct event *ev)
 {
+	int i, j;
 	struct kqop *kqop = arg;
 	struct kevent kev;
 
@@ -391,6 +392,21 @@ kq_del(void *arg, struct event *ev)
 		return (0);
 	}
 
+	for (i = j = 0; i < kqop->nchanges; i++) {
+		if (kqop->changes[i].udata == ev &&
+		    (kqop->changes[i].flags & EV_ADD) != 0)
+			continue;	/* delete this */
+		if (i != j)
+			memcpy(&kqop->changes[j], &kqop->changes[i],
+			    sizeof(struct kevent));
+		j++;
+	}
+	if (kqop->nchanges != j) {
+		kqop->nchanges = j;
+		ev->ev_flags &= ~EVLIST_X_KQINKERNEL;
+		return (0);
+	}
+
 	if (ev->ev_events & EV_READ) {
 		memset(&kev, 0, sizeof(kev));
 		kev.ident = ev->ev_fd;