[ds6-devel] Multiple IPv6 addresses?

[Simone Piunno]

On Mon, Mar 24, 2003 at 09:52:06PM -0800, Chad N. Tindel wrote:

> I noticed that if I run the command:
> 
> ip addr add fec0:0:0:1::ee3f/64 dev eth0 
> 
> multiple times, the IP address will show up in ifconfig output multiple
> times.  Why wouldn't the SIOCSIFADDR ioctl return EEXIST or something 
> similar in this case?  It seems like obviously incorrect behavior.

Hi Chad,

I believe you're right.  Do you feel like trying this patch?
It's for vanilla 2.4.20


--- net/ipv6/addrconf.c.orig	2003-03-25 21:33:55.000000000 +0100
+++ net/ipv6/addrconf.c	2003-03-25 21:34:08.000000000 +0100
@@ -88,6 +88,7 @@
  */
 static struct inet6_ifaddr		*inet6_addr_lst[IN6_ADDR_HSIZE];
 static rwlock_t	addrconf_hash_lock = RW_LOCK_UNLOCKED;
+static rwlock_t	addrconf_add_lock = RW_LOCK_UNLOCKED;
 
 /* Protects inet6 devices */
 rwlock_t addrconf_lock = RW_LOCK_UNLOCKED;
@@ -1032,12 +1033,20 @@
 		return -ENOBUFS;
 
 	scope = ipv6_addr_scope(pfx);
+	
+	read_lock_bh(&addrconf_add_lock);
+	if (!ipv6_chk_addr(pfx, dev)) {
+		read_unlock_bh(&addrconf_add_lock);
+		return -EEXIST;
+	}
 
 	if ((ifp = ipv6_add_addr(idev, pfx, plen, scope, IFA_F_PERMANENT)) != NULL) {
+		read_unlock_bh(&addrconf_add_lock);
 		addrconf_dad_start(ifp);
 		in6_ifa_put(ifp);
 		return 0;
 	}
+	read_unlock_bh(&addrconf_add_lock);
 
 	return -ENOBUFS;
 }
-- 
 Simone Piunno -- http://members.ferrara.linux.it/pioppo 
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