From 5350d54f6cd12eaff623e890744c79b700bd3f17 Mon Sep 17 00:00:00 2001
From: Alexander Duyck <alexander.h.duyck@intel.com>
Date: Mon, 2 Jan 2017 13:32:54 -0800
Subject: [PATCH] ipv4: Do not allow MAIN to be alias for new LOCAL w/ custom
 rules

In the case of custom rules being present we need to handle the case of the
LOCAL table being intialized after the new rule has been added.  To address
that I am adding a new check so that we can make certain we don't use an
alias of MAIN for LOCAL when allocating a new table.

Fixes: 0ddcf43d5d4a ("ipv4: FIB Local/MAIN table collapse")
Reported-by: Oliver Brunel <jjk@jjacky.com>
Signed-off-by: Alexander Duyck <alexander.h.duyck@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
---
 net/ipv4/fib_frontend.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/net/ipv4/fib_frontend.c b/net/ipv4/fib_frontend.c
index 3ff8938893ec..eae0332b0e8c 100644
--- a/net/ipv4/fib_frontend.c
+++ b/net/ipv4/fib_frontend.c
@@ -85,7 +85,7 @@ struct fib_table *fib_new_table(struct net *net, u32 id)
 	if (tb)
 		return tb;
 
-	if (id == RT_TABLE_LOCAL)
+	if (id == RT_TABLE_LOCAL && !net->ipv4.fib_has_custom_rules)
 		alias = fib_new_table(net, RT_TABLE_MAIN);
 
 	tb = fib_trie_table(id, alias);
-- 
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