From: Willy Tarreau <w@1wt.eu>
Date: Mon, 7 Jul 2014 19:07:51 +0000 (+0200)
Subject: BUG/MEDIUM: unix: completely unbind abstract sockets during a pause()
X-Git-Tag: v1.6-dev1~373
X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=fd0e008d9d4db2f860b739bd28f6cd31d9aaf2b5;p=thirdparty%2Fhaproxy.git

BUG/MEDIUM: unix: completely unbind abstract sockets during a pause()

Abstract namespace sockets ignore the shutdown() call and do not make
it possible to temporarily stop listening. The issue it causes is that
during a soft reload, the new process cannot bind, complaining that the
address is already in use.

This change registers a new pause() function for unix sockets and
completely unbinds the abstract ones since it's possible to rebind
them later. It requires the two previous patches as well as preceeding
fixes.

This fix should be backported into 1.5 since the issue apperas there.
---

diff --git a/include/proto/proto_uxst.h b/include/proto/proto_uxst.h
index 9422ea7c2b..8e796ecd17 100644
--- a/include/proto/proto_uxst.h
+++ b/include/proto/proto_uxst.h
@@ -27,6 +27,7 @@
 #include <types/task.h>
 
 void uxst_add_listener(struct listener *listener);
+int uxst_pause_listener(struct listener *l);
 int uxst_get_src(int fd, struct sockaddr *sa, socklen_t salen, int dir);
 int uxst_get_dst(int fd, struct sockaddr *sa, socklen_t salen, int dir);
 
diff --git a/src/proto_uxst.c b/src/proto_uxst.c
index 409c659064..adc1b46603 100644
--- a/src/proto_uxst.c
+++ b/src/proto_uxst.c
@@ -68,6 +68,7 @@ static struct protocol proto_unix = {
 	.disable_all = disable_all_listeners,
 	.get_src = uxst_get_src,
 	.get_dst = uxst_get_dst,
+	.pause = uxst_pause_listener,
 	.listeners = LIST_HEAD_INIT(proto_unix.listeners),
 	.nb_listeners = 0,
 };
@@ -373,6 +374,20 @@ void uxst_add_listener(struct listener *listener)
 	proto_unix.nb_listeners++;
 }
 
+/* Pause a listener. Returns < 0 in case of failure, 0 if the listener
+ * was totally stopped, or > 0 if correctly paused. Nothing is done for
+ * plain unix sockets since currently it's the new process which handles
+ * the renaming. Abstract sockets are completely unbound.
+ */
+int uxst_pause_listener(struct listener *l)
+{
+	if (((struct sockaddr_un *)&l->addr)->sun_path[0])
+		return 1;
+
+	unbind_listener(l);
+	return 0;
+}
+
 
 /*
  * This function initiates a UNIX connection establishment to the target assigned