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

    netfilter: ipset: Fix serious failure in CIDR tracking

to the 3.11-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:
     netfilter-ipset-fix-serious-failure-in-cidr-tracking.patch
and it can be found in the queue-3.11 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree,
please let <[email protected]> know about it.


>From 2cf55125c64d64cc106e204d53b107094762dfdf Mon Sep 17 00:00:00 2001
From: Oliver Smith <[email protected]>
Date: Mon, 16 Sep 2013 20:30:57 +0200
Subject: netfilter: ipset: Fix serious failure in CIDR tracking

From: Oliver Smith <[email protected]>

commit 2cf55125c64d64cc106e204d53b107094762dfdf upstream.

This fixes a serious bug affecting all hash types with a net element -
specifically, if a CIDR value is deleted such that none of the same size
exist any more, all larger (less-specific) values will then fail to
match. Adding back any prefix with a CIDR equal to or more specific than
the one deleted will fix it.

Steps to reproduce:
ipset -N test hash:net
ipset -A test 1.1.0.0/16
ipset -A test 2.2.2.0/24
ipset -T test 1.1.1.1           #1.1.1.1 IS in set
ipset -D test 2.2.2.0/24
ipset -T test 1.1.1.1           #1.1.1.1 IS NOT in set

This is due to the fact that the nets counter was unconditionally
decremented prior to the iteration that shifts up the entries. Now, we
first check if there is a proceeding entry and if not, decrement it and
return. Otherwise, we proceed to iterate and then zero the last element,
which, in most cases, will already be zero.

Signed-off-by: Oliver Smith <[email protected]>
Signed-off-by: Jozsef Kadlecsik <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>

---
 net/netfilter/ipset/ip_set_hash_gen.h |   26 +++++++++++++++-----------
 1 file changed, 15 insertions(+), 11 deletions(-)

--- a/net/netfilter/ipset/ip_set_hash_gen.h
+++ b/net/netfilter/ipset/ip_set_hash_gen.h
@@ -325,18 +325,22 @@ mtype_add_cidr(struct htype *h, u8 cidr,
 static void
 mtype_del_cidr(struct htype *h, u8 cidr, u8 nets_length)
 {
-       u8 i, j;
+       u8 i, j, net_end = nets_length - 1;
 
-       for (i = 0; i < nets_length - 1 && h->nets[i].cidr != cidr; i++)
-               ;
-       h->nets[i].nets--;
-
-       if (h->nets[i].nets != 0)
-               return;
-
-       for (j = i; j < nets_length - 1 && h->nets[j].nets; j++) {
-               h->nets[j].cidr = h->nets[j + 1].cidr;
-               h->nets[j].nets = h->nets[j + 1].nets;
+       for (i = 0; i < nets_length; i++) {
+               if (h->nets[i].cidr != cidr)
+                       continue;
+                if (h->nets[i].nets > 1 || i == net_end ||
+                    h->nets[i + 1].nets == 0) {
+                        h->nets[i].nets--;
+                        return;
+                }
+                for (j = i; j < net_end && h->nets[j].nets; j++) {
+                       h->nets[j].cidr = h->nets[j + 1].cidr;
+                       h->nets[j].nets = h->nets[j + 1].nets;
+                }
+                h->nets[j].nets = 0;
+                return;
        }
 }
 #endif


Patches currently in stable-queue which might be from 
[email protected] are

queue-3.11/netfilter-ipset-fix-serious-failure-in-cidr-tracking.patch
--
To unsubscribe from this list: send the line "unsubscribe stable" in
the body of a message to [email protected]
More majordomo info at  http://vger.kernel.org/majordomo-info.html

Reply via email to