CVS commit: src/sys/net

[Ryota Ozaki]

Module Name:    src
Committed By:   ozaki-r
Date:           Sat Oct 11 10:16:49 UTC 2014

Modified Files:
        src/sys/net: if_vlan.c

Log Message:
Protect vlan_unconfig with a mutex

It is not thread-safe but is likely to be executed in concurrent.
See PR 49264 for more detail.


To generate a diff of this commit:
cvs rdiff -u -r1.75 -r1.76 src/sys/net/if_vlan.c

Please note that diffs are not public domain; they are subject to the
copyright notices on the relevant files.


Modified files:

Index: src/sys/net/if_vlan.c
diff -u src/sys/net/if_vlan.c:1.75 src/sys/net/if_vlan.c:1.76
--- src/sys/net/if_vlan.c:1.75	Thu Oct  9 04:48:12 2014
+++ src/sys/net/if_vlan.c	Sat Oct 11 10:16:49 2014
@@ -1,4 +1,4 @@
-/*	$NetBSD: if_vlan.c,v 1.75 2014/10/09 04:48:12 ozaki-r Exp $	*/
+/*	$NetBSD: if_vlan.c,v 1.76 2014/10/11 10:16:49 ozaki-r Exp $	*/
 
 /*-
  * Copyright (c) 2000, 2001 The NetBSD Foundation, Inc.
@@ -78,7 +78,7 @@
  */
 
 #include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: if_vlan.c,v 1.75 2014/10/09 04:48:12 ozaki-r Exp $");
+__KERNEL_RCSID(0, "$NetBSD: if_vlan.c,v 1.76 2014/10/11 10:16:49 ozaki-r Exp $");
 
 #include "opt_inet.h"
 
@@ -91,6 +91,7 @@ __KERNEL_RCSID(0, "$NetBSD: if_vlan.c,v 
 #include <sys/systm.h>
 #include <sys/proc.h>
 #include <sys/kauth.h>
+#include <sys/mutex.h>
 
 #include <net/bpf.h>
 #include <net/if.h>
@@ -180,6 +181,8 @@ void		vlanattach(int);
 /* XXX This should be a hash table with the tag as the basis of the key. */
 static LIST_HEAD(, ifvlan) ifv_list;
 
+static kmutex_t ifv_mtx __cacheline_aligned;
+
 struct if_clone vlan_cloner =
     IF_CLONE_INITIALIZER("vlan", vlan_clone_create, vlan_clone_destroy);
 
@@ -191,6 +194,7 @@ vlanattach(int n)
 {
 
 	LIST_INIT(&ifv_list);
+	mutex_init(&ifv_mtx, MUTEX_DEFAULT, IPL_NONE);
 	if_clone_attach(&vlan_cloner);
 }
 
@@ -359,8 +363,12 @@ vlan_unconfig(struct ifnet *ifp)
 {
 	struct ifvlan *ifv = ifp->if_softc;
 
-	if (ifv->ifv_p == NULL)
+	mutex_enter(&ifv_mtx);
+
+	if (ifv->ifv_p == NULL) {
+		mutex_exit(&ifv_mtx);
 		return;
+	}
 
 	/*
  	 * Since the interface is being unconfigured, we need to empty the
@@ -412,6 +420,8 @@ vlan_unconfig(struct ifnet *ifp)
 	if_down(ifp);
 	ifp->if_flags &= ~(IFF_UP|IFF_RUNNING);
 	ifp->if_capabilities = 0;
+
+	mutex_exit(&ifv_mtx);
 }
 
 /*