mirror of https://github.com/hak5/openwrt.git
47 lines
2.0 KiB
Diff
47 lines
2.0 KiB
Diff
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From: Alexander Duyck <alexander.h.duyck@redhat.com>
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Date: Tue, 2 Dec 2014 10:58:21 -0800
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Subject: [PATCH] fib_trie: Fix /proc/net/fib_trie when
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CONFIG_IP_MULTIPLE_TABLES is not defined
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In recent testing I had disabled CONFIG_IP_MULTIPLE_TABLES and as a result
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when I ran "cat /proc/net/fib_trie" the main trie was displayed multiple
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times. I found that the problem line of code was in the function
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fib_trie_seq_next. Specifically the line below caused the indexes to go in
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the opposite direction of our traversal:
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h = tb->tb_id & (FIB_TABLE_HASHSZ - 1);
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This issue was that the RT tables are defined such that RT_TABLE_LOCAL is ID
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255, while it is located at TABLE_LOCAL_INDEX of 0, and RT_TABLE_MAIN is 254
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with a TABLE_MAIN_INDEX of 1. This means that the above line will return 1
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for the local table and 0 for main. The result is that fib_trie_seq_next
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will return NULL at the end of the local table, fib_trie_seq_start will
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return the start of the main table, and then fib_trie_seq_next will loop on
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main forever as h will always return 0.
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The fix for this is to reverse the ordering of the two tables. It has the
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advantage of making it so that the tables now print in the same order
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regardless of if multiple tables are enabled or not. In order to make the
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definition consistent with the multiple tables case I simply masked the to
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RT_TABLE_XXX values by (FIB_TABLE_HASHSZ - 1). This way the two table
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layouts should always stay consistent.
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Fixes: 93456b6 ("[IPV4]: Unify access to the routing tables")
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Signed-off-by: Alexander Duyck <alexander.h.duyck@redhat.com>
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Signed-off-by: David S. Miller <davem@davemloft.net>
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---
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--- a/include/net/ip_fib.h
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+++ b/include/net/ip_fib.h
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@@ -201,8 +201,8 @@ void fib_free_table(struct fib_table *tb
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#ifndef CONFIG_IP_MULTIPLE_TABLES
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-#define TABLE_LOCAL_INDEX 0
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-#define TABLE_MAIN_INDEX 1
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+#define TABLE_LOCAL_INDEX (RT_TABLE_LOCAL & (FIB_TABLE_HASHSZ - 1))
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+#define TABLE_MAIN_INDEX (RT_TABLE_MAIN & (FIB_TABLE_HASHSZ - 1))
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static inline struct fib_table *fib_get_table(struct net *net, u32 id)
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{
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