[IPV4]: Fix the fib trie iterator to work with a single entry routing tables

In a kernel with trie routing enabled I had a simple routing setup
with only a single route to the outside world and no default
route. "ip route table list main" showed my the route just fine but
/proc/net/route was an empty file.  What was going on?

Thinking it was a bug in something I did and I looked deeper.  Eventually
I setup a second route and everything looked correct, huh?  Finally I
realized that the it was just the iterator pair in fib_trie_get_first,
fib_trie_get_next just could not handle a routing table with a single entry.

So to save myself and others further confusion, here is a simple fix for
the fib proc iterator so it works even when there is only a single route
in a routing table.

Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: Robert Olsson <robert.olsson@its.uu.se>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Eric W. Biederman 2007-01-24 14:42:04 -08:00 committed by David S. Miller
parent a21b069626
commit 6640e69731

View file

@ -1989,6 +1989,10 @@ static struct node *fib_trie_get_next(struct fib_trie_iter *iter)
unsigned cindex = iter->index; unsigned cindex = iter->index;
struct tnode *p; struct tnode *p;
/* A single entry routing table */
if (!tn)
return NULL;
pr_debug("get_next iter={node=%p index=%d depth=%d}\n", pr_debug("get_next iter={node=%p index=%d depth=%d}\n",
iter->tnode, iter->index, iter->depth); iter->tnode, iter->index, iter->depth);
rescan: rescan:
@ -2037,11 +2041,18 @@ static struct node *fib_trie_get_first(struct fib_trie_iter *iter,
if(!iter) if(!iter)
return NULL; return NULL;
if (n && IS_TNODE(n)) { if (n) {
iter->tnode = (struct tnode *) n; if (IS_TNODE(n)) {
iter->trie = t; iter->tnode = (struct tnode *) n;
iter->index = 0; iter->trie = t;
iter->depth = 1; iter->index = 0;
iter->depth = 1;
} else {
iter->tnode = NULL;
iter->trie = t;
iter->index = 0;
iter->depth = 0;
}
return n; return n;
} }
return NULL; return NULL;