svn commit: r220475 - stable/7/usr.sbin/rtadvd

[Bjoern A. Zeeb]

Author: bz
Date: Sat Apr  9 10:18:46 2011
New Revision: 220475
URL: http://svn.freebsd.org/changeset/base/220475

Log:
  MFC r219184:
  
    Prevent crashes from a race when (cloned) interfaces go away.
  
  PR:		bin/152143
    Submitted by:	Przemyslaw Frasunek (przemyslaw frasunek.com)
    Tested by:	Przemyslaw Frasunek (przemyslaw frasunek.com)

Modified:
  stable/7/usr.sbin/rtadvd/rtadvd.c
Directory Properties:
  stable/7/usr.sbin/rtadvd/   (props changed)

Modified: stable/7/usr.sbin/rtadvd/rtadvd.c
==============================================================================
--- stable/7/usr.sbin/rtadvd/rtadvd.c	Sat Apr  9 09:33:36 2011	(r220474)
+++ stable/7/usr.sbin/rtadvd/rtadvd.c	Sat Apr  9 10:18:46 2011	(r220475)
@@ -667,14 +667,16 @@ rtadvd_input()
 	}
 
 	/*
-	 * If we happen to receive data on an interface which is now down,
-	 * just discard the data.
+	 * If we happen to receive data on an interface which is now gone
+	 * or down, just discard the data.
 	 */
-	if ((iflist[pi->ipi6_ifindex]->ifm_flags & IFF_UP) == 0) {
+	if (iflist[pi->ipi6_ifindex] == NULL ||
+	    (iflist[pi->ipi6_ifindex]->ifm_flags & IFF_UP) == 0) {
 		syslog(LOG_INFO,
 		       "<%s> received data on a disabled interface (%s)",
 		       __func__,
-		       if_indextoname(pi->ipi6_ifindex, ifnamebuf));
+		       (iflist[pi->ipi6_ifindex] == NULL) ? "[gone]" :
+			    if_indextoname(pi->ipi6_ifindex, ifnamebuf));
 		return;
 	}