From e4e92fb160d7bef689c6ad00108b4e52599ca05e Mon Sep 17 00:00:00 2001 From: David Ahern Date: Mon, 15 Oct 2018 18:56:51 -0700 Subject: [PATCH] net/ipv4: Bail early if user only wants prefix entries Unlike IPv6, IPv4 does not have routes marked with RTF_PREFIX_RT. If the flag is set in the dump request, just return. In the process of this change, move the CLONE check to use the new filter flags. Signed-off-by: David Ahern Signed-off-by: David S. Miller --- net/ipv4/fib_frontend.c | 8 ++++++-- 1 file changed, 6 insertions(+), 2 deletions(-) diff --git a/net/ipv4/fib_frontend.c b/net/ipv4/fib_frontend.c index e86ca2255181..5bf653f36911 100644 --- a/net/ipv4/fib_frontend.c +++ b/net/ipv4/fib_frontend.c @@ -886,10 +886,14 @@ static int inet_dump_fib(struct sk_buff *skb, struct netlink_callback *cb) err = ip_valid_fib_dump_req(net, nlh, &filter, cb); if (err < 0) return err; + } else if (nlmsg_len(nlh) >= sizeof(struct rtmsg)) { + struct rtmsg *rtm = nlmsg_data(nlh); + + filter.flags = rtm->rtm_flags & (RTM_F_PREFIX | RTM_F_CLONED); } - if (nlmsg_len(nlh) >= sizeof(struct rtmsg) && - ((struct rtmsg *)nlmsg_data(nlh))->rtm_flags & RTM_F_CLONED) + /* fib entries are never clones and ipv4 does not use prefix flag */ + if (filter.flags & (RTM_F_PREFIX | RTM_F_CLONED)) return skb->len; if (filter.table_id) {