net: ipv4: Add extack message for invalid prefix or length
Add extack error message for invalid prefix length and invalid prefix.
Example of the latter is a route spec containing 172.16.100.1/24, where
the /24 mask means the lower 8-bits should be 0. Amazing how easy that
one is to overlook when an EINVAL is returned.
Signed-off-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/ipv4/fib_trie.c b/net/ipv4/fib_trie.c
index 9bd46e1..a624d38 100644
--- a/net/ipv4/fib_trie.c
+++ b/net/ipv4/fib_trie.c
@@ -1099,13 +1099,18 @@ static int fib_insert_alias(struct trie *t, struct key_vector *tp,
return 0;
}
-static bool fib_valid_key_len(u32 key, u8 plen)
+static bool fib_valid_key_len(u32 key, u8 plen, struct netlink_ext_ack *extack)
{
- if (plen > KEYLENGTH)
+ if (plen > KEYLENGTH) {
+ NL_SET_ERR_MSG(extack, "Invalid prefix length");
return false;
+ }
- if ((plen < KEYLENGTH) && (key << plen))
+ if ((plen < KEYLENGTH) && (key << plen)) {
+ NL_SET_ERR_MSG(extack,
+ "Invalid prefix for given prefix length");
return false;
+ }
return true;
}
@@ -1128,7 +1133,7 @@ int fib_table_insert(struct net *net, struct fib_table *tb,
key = ntohl(cfg->fc_dst);
- if (!fib_valid_key_len(key, plen))
+ if (!fib_valid_key_len(key, plen, extack))
return -EINVAL;
pr_debug("Insert table=%u %08x/%d\n", tb->tb_id, key, plen);
@@ -1516,7 +1521,7 @@ static void fib_remove_alias(struct trie *t, struct key_vector *tp,
/* Caller must hold RTNL. */
int fib_table_delete(struct net *net, struct fib_table *tb,
- struct fib_config *cfg)
+ struct fib_config *cfg, struct netlink_ext_ack *extack)
{
struct trie *t = (struct trie *) tb->tb_data;
struct fib_alias *fa, *fa_to_delete;
@@ -1528,7 +1533,7 @@ int fib_table_delete(struct net *net, struct fib_table *tb,
key = ntohl(cfg->fc_dst);
- if (!fib_valid_key_len(key, plen))
+ if (!fib_valid_key_len(key, plen, extack))
return -EINVAL;
l = fib_find_node(t, &tp, key);