Patch "ipv6: addrconf: fix generation of new temporary addresses" has been added to the 4.9-stable tree

Patch "ipv6: addrconf: fix generation of new temporary addresses" has been added to the 4.9-stable tree

[gregkh]

This is a note to let you know that I've just added the patch titled

    ipv6: addrconf: fix generation of new temporary addresses

to the 4.9-stable tree which can be found at:
    http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
     ipv6-addrconf-fix-generation-of-new-temporary-addresses.patch
and it can be found in the queue-4.9 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@vger.kernel.org> know about it.


>From foo@baz Thu Jun 15 11:38:13 CEST 2017
From: Marcus Huewe <suse-tux@gmx.de>
Date: Tue, 23 May 2017 21:53:49 -0400
Subject: ipv6: addrconf: fix generation of new temporary addresses

From: Marcus Huewe <suse-tux@gmx.de>


[ Upstream commit a11a7f71cac209c7c9cca66eb506e1ebb033a3b3 ]

Under some circumstances it is possible that no new temporary addresses
will be generated.

For instance, addrconf_prefix_rcv_add_addr() indirectly calls
ipv6_create_tempaddr(), which creates a tentative temporary address and
starts dad. Next, addrconf_prefix_rcv_add_addr() indirectly calls
addrconf_verify_rtnl(). Now, assume that the previously created temporary
address has the least preferred lifetime among all existing addresses and
is still tentative (that is, dad is still running). Hence, the next run of
addrconf_verify_rtnl() is performed when the preferred lifetime of the
temporary address ends. If dad succeeds before the next run, the temporary
address becomes deprecated during the next run, but no new temporary
address is generated.

In order to fix this, schedule the next addrconf_verify_rtnl() run slightly
before the temporary address becomes deprecated, if dad succeeded.

Signed-off-by: Marcus Huewe <suse-tux@gmx.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <alexander.levin@verizon.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
 net/ipv6/addrconf.c |    6 ++++++
 1 file changed, 6 insertions(+)

--- a/net/ipv6/addrconf.c
+++ b/net/ipv6/addrconf.c
@@ -4004,6 +4004,12 @@ static void addrconf_dad_completed(struc
 
 	if (bump_id)
 		rt_genid_bump_ipv6(dev_net(dev));
+
+	/* Make sure that a new temporary address will be created
+	 * before this temporary address becomes deprecated.
+	 */
+	if (ifp->flags & IFA_F_TEMPORARY)
+		addrconf_verify_rtnl();
 }
 
 static void addrconf_dad_run(struct inet6_dev *idev)


Patches currently in stable-queue which might be from suse-tux@gmx.de are

queue-4.9/ipv6-addrconf-fix-generation-of-new-temporary-addresses.patch