From: Alexander Duyck Date: Tue, 10 Mar 2015 18:25:41 +0000 (-0700) Subject: fib_trie: Correctly handle case of key == 0 in leaf_walk_rcu X-Git-Tag: v4.1-rc1~128^2~280 X-Git-Url: https://git.kernelconcepts.de/?p=karo-tx-linux.git;a=commitdiff_plain;h=3ec320dd5c9465fbed3c84dd14ed3941ce757823 fib_trie: Correctly handle case of key == 0 in leaf_walk_rcu In the case of a trie that had no tnodes with a key of 0 the initial look-up would fail resulting in an out-of-bounds cindex on the first tnode. This resulted in an entire trie being skipped. In order resolve this I have updated the cindex logic in the initial look-up so that if the key is zero we will always traverse the child zero path. Fixes: 8be33e95 ("fib_trie: Fib walk rcu should take a tnode and key instead of a trie and a leaf") Reported-by: Sabrina Dubroca Signed-off-by: Alexander Duyck Tested-by: Sabrina Dubroca Signed-off-by: David S. Miller --- diff --git a/net/ipv4/fib_trie.c b/net/ipv4/fib_trie.c index fcfa9825a816..44cab1d41463 100644 --- a/net/ipv4/fib_trie.c +++ b/net/ipv4/fib_trie.c @@ -1530,7 +1530,7 @@ static struct key_vector *leaf_walk_rcu(struct key_vector **tn, t_key key) do { /* record parent and next child index */ pn = n; - cindex = get_index(key, pn); + cindex = key ? get_index(key, pn) : 0; if (cindex >> pn->bits) break;