From 35e8c7ba0863acadd4b9badd09740af7a8331125 Mon Sep 17 00:00:00 2001 From: Roopa Prabhu Date: Fri, 29 Jun 2018 14:32:15 -0700 Subject: net: fib_rules: bring back rule_exists to match rule during add After commit f9d4b0c1e969 ("fib_rules: move common handling of newrule delrule msgs into fib_nl2rule"), rule_exists got replaced by rule_find for existing rule lookup in both the add and del paths. While this is good for the delete path, it solves a few problems but opens up a few invalid key matches in the add path. $ip -4 rule add table main tos 10 fwmark 1 $ip -4 rule add table main tos 10 RTNETLINK answers: File exists The problem here is rule_find does not check if the key masks in the new and old rule are the same and hence ends up matching a more secific rule. Rule key masks cannot be easily compared today without an elaborate if-else block. Its best to introduce key masks for easier and accurate rule comparison in the future. Until then, due to fear of regressions this patch re-introduces older loose rule_exists during add. Also fixes both rule_exists and rule_find to cover missing attributes. Fixes: f9d4b0c1e969 ("fib_rules: move common handling of newrule delrule msgs into fib_nl2rule") Signed-off-by: Roopa Prabhu Signed-off-by: David S. Miller --- net/core/fib_rules.c | 72 +++++++++++++++++++++++++++++++++++++++++++++++++++- 1 file changed, 71 insertions(+), 1 deletion(-) (limited to 'net') diff --git a/net/core/fib_rules.c b/net/core/fib_rules.c index bc8425d81022..f64aa13811ea 100644 --- a/net/core/fib_rules.c +++ b/net/core/fib_rules.c @@ -444,6 +444,9 @@ static struct fib_rule *rule_find(struct fib_rules_ops *ops, if (rule->ip_proto && r->ip_proto != rule->ip_proto) continue; + if (rule->proto && r->proto != rule->proto) + continue; + if (fib_rule_port_range_set(&rule->sport_range) && !fib_rule_port_range_compare(&r->sport_range, &rule->sport_range)) @@ -653,6 +656,73 @@ errout: return err; } +static int rule_exists(struct fib_rules_ops *ops, struct fib_rule_hdr *frh, + struct nlattr **tb, struct fib_rule *rule) +{ + struct fib_rule *r; + + list_for_each_entry(r, &ops->rules_list, list) { + if (r->action != rule->action) + continue; + + if (r->table != rule->table) + continue; + + if (r->pref != rule->pref) + continue; + + if (memcmp(r->iifname, rule->iifname, IFNAMSIZ)) + continue; + + if (memcmp(r->oifname, rule->oifname, IFNAMSIZ)) + continue; + + if (r->mark != rule->mark) + continue; + + if (r->suppress_ifgroup != rule->suppress_ifgroup) + continue; + + if (r->suppress_prefixlen != rule->suppress_prefixlen) + continue; + + if (r->mark_mask != rule->mark_mask) + continue; + + if (r->tun_id != rule->tun_id) + continue; + + if (r->fr_net != rule->fr_net) + continue; + + if (r->l3mdev != rule->l3mdev) + continue; + + if (!uid_eq(r->uid_range.start, rule->uid_range.start) || + !uid_eq(r->uid_range.end, rule->uid_range.end)) + continue; + + if (r->ip_proto != rule->ip_proto) + continue; + + if (r->proto != rule->proto) + continue; + + if (!fib_rule_port_range_compare(&r->sport_range, + &rule->sport_range)) + continue; + + if (!fib_rule_port_range_compare(&r->dport_range, + &rule->dport_range)) + continue; + + if (!ops->compare(r, frh, tb)) + continue; + return 1; + } + return 0; +} + int fib_nl_newrule(struct sk_buff *skb, struct nlmsghdr *nlh, struct netlink_ext_ack *extack) { @@ -687,7 +757,7 @@ int fib_nl_newrule(struct sk_buff *skb, struct nlmsghdr *nlh, goto errout; if ((nlh->nlmsg_flags & NLM_F_EXCL) && - rule_find(ops, frh, tb, rule, user_priority)) { + rule_exists(ops, frh, tb, rule)) { err = -EEXIST; goto errout_free; } -- cgit