From: melifaro <melifaro@FreeBSD.org>
Date: Sun, 18 Oct 2015 12:26:25 +0000 (+0000)
Subject: Fix deletion of ifaddr lle entries when deleting prefix from interface in
X-Git-Url: http://xenbits.xensource.com/gitweb?a=commitdiff_plain;h=b26720e1df1ea61d1807e2509b26c7563dc423f6;p=people%2Fjulieng%2Ffreebsd.git

Fix deletion of ifaddr lle entries when deleting prefix from interface in
  down state.

Regression appeared in r287789, where the "prefix has no corresponding
  installed route" case was forgotten. Additionally, lltable_delete_addr()
  was called with incorrect byte order (default is network for lltable code).
While here, improve comments on given cases and byte order.

PR:		203573
Submitted by:	phk
---

diff --git a/sys/netinet/in.c b/sys/netinet/in.c
index 1441936c3808..2607a1750ffd 100644
--- a/sys/netinet/in.c
+++ b/sys/netinet/in.c
@@ -734,14 +734,10 @@ in_scrubprefixlle(struct in_ifaddr *ia, int all, u_int flags)
 	struct sockaddr *saddr, *smask;
 	struct ifnet *ifp;
 
-	/*
-	 * remove all L2 entries on the given prefix
-	 */
 	saddr = (struct sockaddr *)&addr;
 	bzero(&addr, sizeof(addr));
 	addr.sin_len = sizeof(addr);
 	addr.sin_family = AF_INET;
-	addr.sin_addr.s_addr = ntohl(ia->ia_addr.sin_addr.s_addr);
 	smask = (struct sockaddr *)&mask;
 	bzero(&mask, sizeof(mask));
 	mask.sin_len = sizeof(mask);
@@ -749,10 +745,21 @@ in_scrubprefixlle(struct in_ifaddr *ia, int all, u_int flags)
 	mask.sin_addr.s_addr = ia->ia_subnetmask;
 	ifp = ia->ia_ifp;
 
-	if (all)
+	if (all) {
+
+		/*
+		 * Remove all L2 entries matching given prefix.
+		 * Convert address to host representation to avoid
+		 * doing this on every callback. ia_subnetmask is already
+		 * stored in host representation.
+		 */
+		addr.sin_addr.s_addr = ntohl(ia->ia_addr.sin_addr.s_addr);
 		lltable_prefix_free(AF_INET, saddr, smask, flags);
-	else
+	} else {
+		/* Remove interface address only */
+		addr.sin_addr.s_addr = ia->ia_addr.sin_addr.s_addr;
 		lltable_delete_addr(LLTABLE(ifp), LLE_IFADDR, saddr);
+	}
 }
 
 /*
@@ -808,6 +815,14 @@ in_scrubprefix(struct in_ifaddr *target, u_int flags)
 		fibnum = V_rt_add_addr_allfibs ? RT_ALL_FIBS :
 			target->ia_ifp->if_fib;
 		rt_addrmsg(RTM_DELETE, &target->ia_ifa, fibnum);
+	
+		/*
+		 * Removing address from !IFF_UP interface or
+		 * prefix which exists on other interface (along with route).
+		 * No entries should exist here except target addr.
+		 * Given that, delete this entry only.
+		 */
+		in_scrubprefixlle(target, 0, flags);
 		return (0);
 	}