47 lines
2 KiB
Diff
47 lines
2 KiB
Diff
|
From: Alexander Duyck <alexander.h.duyck@redhat.com>
|
||
|
|
Date: Tue, 2 Dec 2014 10:58:21 -0800
|
||
|
|
Subject: [PATCH] fib_trie: Fix /proc/net/fib_trie when
|
||
|
|
CONFIG_IP_MULTIPLE_TABLES is not defined
|
||
|
|
|
||
|
|
In recent testing I had disabled CONFIG_IP_MULTIPLE_TABLES and as a result
|
||
|
|
when I ran "cat /proc/net/fib_trie" the main trie was displayed multiple
|
||
|
|
times. I found that the problem line of code was in the function
|
||
|
|
fib_trie_seq_next. Specifically the line below caused the indexes to go in
|
||
|
|
the opposite direction of our traversal:
|
||
|
|
|
||
|
|
h = tb->tb_id & (FIB_TABLE_HASHSZ - 1);
|
||
|
|
|
||
|
|
This issue was that the RT tables are defined such that RT_TABLE_LOCAL is ID
|
||
|
|
255, while it is located at TABLE_LOCAL_INDEX of 0, and RT_TABLE_MAIN is 254
|
||
|
|
with a TABLE_MAIN_INDEX of 1. This means that the above line will return 1
|
||
|
|
for the local table and 0 for main. The result is that fib_trie_seq_next
|
||
|
|
will return NULL at the end of the local table, fib_trie_seq_start will
|
||
|
|
return the start of the main table, and then fib_trie_seq_next will loop on
|
||
|
|
main forever as h will always return 0.
|
||
|
|
|
||
|
|
The fix for this is to reverse the ordering of the two tables. It has the
|
||
|
|
advantage of making it so that the tables now print in the same order
|
||
|
|
regardless of if multiple tables are enabled or not. In order to make the
|
||
|
|
definition consistent with the multiple tables case I simply masked the to
|
||
|
|
RT_TABLE_XXX values by (FIB_TABLE_HASHSZ - 1). This way the two table
|
||
|
|
layouts should always stay consistent.
|
||
|
|
|
||
|
|
Fixes: 93456b6 ("[IPV4]: Unify access to the routing tables")
|
||
|
|
Signed-off-by: Alexander Duyck <alexander.h.duyck@redhat.com>
|
||
|
|
Signed-off-by: David S. Miller <davem@davemloft.net>
|
||
|
|
---
|
||
|
|
|
||
|
|
--- a/include/net/ip_fib.h
|
||
|
|
+++ b/include/net/ip_fib.h
|
||
|
|
@@ -201,8 +201,8 @@ void fib_free_table(struct fib_table *tb
|
||
|
|
|
||
|
|
#ifndef CONFIG_IP_MULTIPLE_TABLES
|
||
|
|
|
||
|
|
-#define TABLE_LOCAL_INDEX 0
|
||
|
|
-#define TABLE_MAIN_INDEX 1
|
||
|
|
+#define TABLE_LOCAL_INDEX (RT_TABLE_LOCAL & (FIB_TABLE_HASHSZ - 1))
|
||
|
|
+#define TABLE_MAIN_INDEX (RT_TABLE_MAIN & (FIB_TABLE_HASHSZ - 1))
|
||
|
|
|
||
|
|
static inline struct fib_table *fib_get_table(struct net *net, u32 id)
|
||
|
|
{
|