From f9121355eb6f9babadb97bf5b34ab0cce7764406 Mon Sep 17 00:00:00 2001
From: Pablo Neira Ayuso <pablo@netfilter.org>
Date: Wed, 1 Mar 2017 18:15:11 +0100
Subject: [PATCH] netfilter: nft_set_rbtree: incorrect assumption on lower
 interval lookups

In case of adjacent ranges, we may indeed see either the high part of
the range in first place or the low part of it. Remove this incorrect
assumption, let's make sure we annotate the low part of the interval in
case of we have adjacent interva intervals so we hit a matching in
lookups.

Reported-by: Simon Hanisch <hanisch@wh2.tu-dresden.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
---
 net/netfilter/nft_set_rbtree.c | 9 ++++-----
 1 file changed, 4 insertions(+), 5 deletions(-)

diff --git a/net/netfilter/nft_set_rbtree.c b/net/netfilter/nft_set_rbtree.c
index 71e8fb886a73b..78dfbf9588b36 100644
--- a/net/netfilter/nft_set_rbtree.c
+++ b/net/netfilter/nft_set_rbtree.c
@@ -60,11 +60,10 @@ static bool nft_rbtree_lookup(const struct net *net, const struct nft_set *set,
 		d = memcmp(this, key, set->klen);
 		if (d < 0) {
 			parent = parent->rb_left;
-			/* In case of adjacent ranges, we always see the high
-			 * part of the range in first place, before the low one.
-			 * So don't update interval if the keys are equal.
-			 */
-			if (interval && nft_rbtree_equal(set, this, interval))
+			if (interval &&
+			    nft_rbtree_equal(set, this, interval) &&
+			    nft_rbtree_interval_end(this) &&
+			    !nft_rbtree_interval_end(interval))
 				continue;
 			interval = rbe;
 		} else if (d > 0)
-- 
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