From e5a9a8ead8b4c72b575c0798879aa50b2820ce7c Mon Sep 17 00:00:00 2001
From: Robert Watson <rwatson@FreeBSD.org>
Date: Sun, 19 Apr 2009 21:36:18 +0000
Subject: [PATCH] Lock the interface address list while iterating a network
 interface's address list when searching for a link-layer address to use
 during uuid generation.

MFC after:	2 weeks
---
 sys/kern/kern_uuid.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/sys/kern/kern_uuid.c b/sys/kern/kern_uuid.c
index 16105e9cee52..eec37efe14f9 100644
--- a/sys/kern/kern_uuid.c
+++ b/sys/kern/kern_uuid.c
@@ -101,16 +101,19 @@ uuid_node(uint16_t *node)
 	IFNET_RLOCK();
 	TAILQ_FOREACH(ifp, &V_ifnet, if_link) {
 		/* Walk the address list */
+		IF_ADDR_LOCK(ifp);
 		TAILQ_FOREACH(ifa, &ifp->if_addrhead, ifa_link) {
 			sdl = (struct sockaddr_dl*)ifa->ifa_addr;
 			if (sdl != NULL && sdl->sdl_family == AF_LINK &&
 			    sdl->sdl_type == IFT_ETHER) {
 				/* Got a MAC address. */
 				bcopy(LLADDR(sdl), node, UUID_NODE_LEN);
+				IF_ADDR_UNLOCK(ifp);
 				IFNET_RUNLOCK();
 				return;
 			}
 		}
+		IF_ADDR_UNLOCK(ifp);
 	}
 	IFNET_RUNLOCK();