From: mvs <mvs@openbsd.org>
Date: Fri, 28 Jun 2024 21:30:24 +0000 (+0000)
Subject: Restore original EPIPE and ENOTCONN errors priority in the uipc_send()
X-Git-Url: http://artulab.com/gitweb/?a=commitdiff_plain;h=161e4927333a61fe54f42c8aaa9fa8d7bba8983b;p=openbsd

Restore original EPIPE and ENOTCONN errors priority in the uipc_send()
path changed in rev 1.206. At least acme-client(1) is not happy with
this change.

Reported by claudio. Tests and ok by bluhm.
---

diff --git a/sys/kern/uipc_socket2.c b/sys/kern/uipc_socket2.c
index df5086c8627..27edd54afb4 100644
--- a/sys/kern/uipc_socket2.c
+++ b/sys/kern/uipc_socket2.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: uipc_socket2.c,v 1.155 2024/05/17 19:11:14 mvs Exp $	*/
+/*	$OpenBSD: uipc_socket2.c,v 1.156 2024/06/28 21:30:24 mvs Exp $	*/
 /*	$NetBSD: uipc_socket2.c,v 1.11 1996/02/04 02:17:55 christos Exp $	*/
 
 /*
@@ -160,8 +160,6 @@ void
 soisdisconnected(struct socket *so)
 {
 	soassertlocked(so);
-	so->so_state &= ~(SS_ISCONNECTING|SS_ISCONNECTED|SS_ISDISCONNECTING);
-	so->so_state |= SS_ISDISCONNECTED;
 
 	mtx_enter(&so->so_rcv.sb_mtx);
 	so->so_rcv.sb_state |= SS_CANTRCVMORE;
@@ -171,6 +169,9 @@ soisdisconnected(struct socket *so)
 	so->so_snd.sb_state |= SS_CANTSENDMORE;
 	mtx_leave(&so->so_snd.sb_mtx);
 
+	so->so_state &= ~(SS_ISCONNECTING|SS_ISCONNECTED|SS_ISDISCONNECTING);
+	so->so_state |= SS_ISDISCONNECTED;
+
 	wakeup(&so->so_timeo);
 	sowwakeup(so);
 	sorwakeup(so);
diff --git a/sys/kern/uipc_usrreq.c b/sys/kern/uipc_usrreq.c
index bbedc6588de..1dbe0e72eef 100644
--- a/sys/kern/uipc_usrreq.c
+++ b/sys/kern/uipc_usrreq.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: uipc_usrreq.c,v 1.207 2024/06/26 12:23:36 mvs Exp $	*/
+/*	$OpenBSD: uipc_usrreq.c,v 1.208 2024/06/28 21:30:24 mvs Exp $	*/
 /*	$NetBSD: uipc_usrreq.c,v 1.18 1996/02/09 19:00:50 christos Exp $	*/
 
 /*
@@ -513,6 +513,14 @@ uipc_send(struct socket *so, struct mbuf *m, struct mbuf *nam,
 			goto out;
 	}
 
+	/*
+	 * We hold both solock() and `sb_mtx' mutex while modifying
+	 * SS_CANTSENDMORE flag. solock() is enough to check it.
+	 */
+	if (so->so_snd.sb_state & SS_CANTSENDMORE) {
+		error = EPIPE;
+		goto dispose;
+	}
 	if (unp->unp_conn == NULL) {
 		error = ENOTCONN;
 		goto dispose;
@@ -531,12 +539,6 @@ uipc_send(struct socket *so, struct mbuf *m, struct mbuf *nam,
 	 */
 	mtx_enter(&so2->so_rcv.sb_mtx);
 	mtx_enter(&so->so_snd.sb_mtx);
-	if (so->so_snd.sb_state & SS_CANTSENDMORE) {
-		mtx_leave(&so->so_snd.sb_mtx);
-		mtx_leave(&so2->so_rcv.sb_mtx);
-		error = EPIPE;
-		goto dispose;
-	}
 	if (control) {
 		if (sbappendcontrol(so2, &so2->so_rcv, m, control)) {
 			control = NULL;
diff --git a/sys/miscfs/fifofs/fifo_vnops.c b/sys/miscfs/fifofs/fifo_vnops.c
index 97b14c1bf2d..aa04381db4d 100644
--- a/sys/miscfs/fifofs/fifo_vnops.c
+++ b/sys/miscfs/fifofs/fifo_vnops.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: fifo_vnops.c,v 1.105 2024/05/03 17:43:09 mvs Exp $	*/
+/*	$OpenBSD: fifo_vnops.c,v 1.106 2024/06/28 21:30:24 mvs Exp $	*/
 /*	$NetBSD: fifo_vnops.c,v 1.18 1996/03/16 23:52:42 christos Exp $	*/
 
 /*
@@ -174,10 +174,16 @@ fifo_open(void *v)
 			return (error);
 		}
 		fip->fi_readers = fip->fi_writers = 0;
+		/*
+		 * Should take both solock() and `sb_mtx' mutex for
+		 * SS_CANTSENDMORE flag modifications.
+		 */
+		solock(wso);
 		mtx_enter(&wso->so_snd.sb_mtx);
 		wso->so_snd.sb_state |= SS_CANTSENDMORE;
 		wso->so_snd.sb_lowat = PIPE_BUF;
 		mtx_leave(&wso->so_snd.sb_mtx);
+		sounlock(wso);
 	} else {
 		rso = fip->fi_readsock;
 		wso = fip->fi_writesock;
@@ -185,9 +191,11 @@ fifo_open(void *v)
 	if (ap->a_mode & FREAD) {
 		fip->fi_readers++;
 		if (fip->fi_readers == 1) {
+			solock(wso);
 			mtx_enter(&wso->so_snd.sb_mtx);
 			wso->so_snd.sb_state &= ~SS_CANTSENDMORE;
 			mtx_leave(&wso->so_snd.sb_mtx);
+			sounlock(wso);
 			if (fip->fi_writers > 0)
 				wakeup(&fip->fi_writers);
 		}