netfilter: nft_set_rbtree: handle element re-addition after deletion

The existing code selects no next branch to be inspected when re-inserting an inactive element into the rb-tree, looping endlessly. This patch restricts the check for active elements to the EEXIST case only. Fixes: e701001 ("netfilter: nft_rbtree: allow adjacent intervals with dynamic updates") Reported-by: Wolfgang Bumiller <[email protected]> Tested-by: Wolfgang Bumiller <[email protected]> Signed-off-by: Pablo Neira Ayuso <[email protected]>
ammarfaizi2 · May 23, 2017 · d2df92e · d2df92e
1 parent f3c0eb0
commit d2df92e
Showing 1 changed file with 11 additions and 11 deletions.
diff --git a/net/netfilter/nft_set_rbtree.c b/net/netfilter/nft_set_rbtree.c
@@ -116,17 +116,17 @@ static int __nft_rbtree_insert(const struct net *net, const struct nft_set *set,
 		else if (d > 0)
 			p = &parent->rb_right;
 		else {
-			if (nft_set_elem_active(&rbe->ext, genmask)) {
-				if (nft_rbtree_interval_end(rbe) &&
-				    !nft_rbtree_interval_end(new))
-					p = &parent->rb_left;
-				else if (!nft_rbtree_interval_end(rbe) &&
-					 nft_rbtree_interval_end(new))
-					p = &parent->rb_right;
-				else {
-					*ext = &rbe->ext;
-					return -EEXIST;
-				}
+			if (nft_rbtree_interval_end(rbe) &&
+			    !nft_rbtree_interval_end(new)) {
+				p = &parent->rb_left;
+			} else if (!nft_rbtree_interval_end(rbe) &&
+				   nft_rbtree_interval_end(new)) {
+				p = &parent->rb_right;
+			} else if (nft_set_elem_active(&rbe->ext, genmask)) {
+				*ext = &rbe->ext;
+				return -EEXIST;
+			} else {
+				p = &parent->rb_left;
 			}
 		}
 	}