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| author | Kuniyuki Iwashima <kuniyu@google.com> | 2026-06-29 18:11:00 +0000 |
|---|---|---|
| committer | Paolo Abeni <pabeni@redhat.com> | 2026-07-01 18:42:34 +0200 |
| commit | 34ea2499389e7a2f1522682e003b257eccda26be (patch) | |
| tree | e33210b8f5dba43ece5cb3b9f0e77717334a713d /net | |
| parent | facce49f29ccec1cf7fd916331c9a25c9ad75869 (diff) | |
| download | linux-next-34ea2499389e7a2f1522682e003b257eccda26be.tar.gz linux-next-34ea2499389e7a2f1522682e003b257eccda26be.zip | |
net: fib_rules: Use dev_get_by_name_rcu().
We will no longer hold RTNL for RTM_NEWRULE and RMT_DELRULE
except for the first IPv4 RTM_NEWRULE.
Let's covnert __dev_get_by_name() in fib_nl2rule_rtnl() to
dev_get_by_name_rcu() and rename it to fib_nl2rule_locked().
Note that dev_get_by_name_rcu() must be called inside ops->lock
to serialise fib_rules_event() by __dev_change_net_namespace().
Signed-off-by: Kuniyuki Iwashima <kuniyu@google.com>
Link: https://patch.msgid.link/20260629181226.1929658-9-kuniyu@google.com
Reviewed-by: Ido Schimmel <idosch@nvidia.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Diffstat (limited to 'net')
| -rw-r--r-- | net/core/fib_rules.c | 24 |
1 files changed, 14 insertions, 10 deletions
diff --git a/net/core/fib_rules.c b/net/core/fib_rules.c index 5eef5d6ace82..2b652dd83241 100644 --- a/net/core/fib_rules.c +++ b/net/core/fib_rules.c @@ -734,10 +734,10 @@ errout: return err; } -static int fib_nl2rule_rtnl(struct fib_rule *nlrule, - struct fib_rules_ops *ops, - struct nlattr *tb[], - struct netlink_ext_ack *extack) +static int fib_nl2rule_locked(struct fib_rule *nlrule, + struct fib_rules_ops *ops, + struct nlattr *tb[], + struct netlink_ext_ack *extack) { if (!tb[FRA_PRIORITY]) nlrule->pref = fib_default_rule_pref(ops); @@ -748,12 +748,14 @@ static int fib_nl2rule_rtnl(struct fib_rule *nlrule, return -EINVAL; } + rcu_read_lock(); + if (tb[FRA_IIFNAME]) { struct net_device *dev; - dev = __dev_get_by_name(nlrule->fr_net, nlrule->iifname); + dev = dev_get_by_name_rcu(nlrule->fr_net, nlrule->iifname); if (dev) { - nlrule->iifindex = dev->ifindex; + nlrule->iifindex = READ_ONCE(dev->ifindex); nlrule->iif_is_l3_master = netif_is_l3_master(dev); } } @@ -761,13 +763,15 @@ static int fib_nl2rule_rtnl(struct fib_rule *nlrule, if (tb[FRA_OIFNAME]) { struct net_device *dev; - dev = __dev_get_by_name(nlrule->fr_net, nlrule->oifname); + dev = dev_get_by_name_rcu(nlrule->fr_net, nlrule->oifname); if (dev) { - nlrule->oifindex = dev->ifindex; + nlrule->oifindex = READ_ONCE(dev->ifindex); nlrule->oif_is_l3_master = netif_is_l3_master(dev); } } + rcu_read_unlock(); + return 0; } @@ -906,7 +910,7 @@ int fib_newrule(struct net *net, struct sk_buff *skb, struct nlmsghdr *nlh, rtnl_net_lock(net); mutex_lock(&ops->lock); - err = fib_nl2rule_rtnl(rule, ops, tb, extack); + err = fib_nl2rule_locked(rule, ops, tb, extack); if (err) goto errout_free; @@ -1038,7 +1042,7 @@ int fib_delrule(struct net *net, struct sk_buff *skb, struct nlmsghdr *nlh, rtnl_net_lock(net); mutex_lock(&ops->lock); - err = fib_nl2rule_rtnl(nlrule, ops, tb, extack); + err = fib_nl2rule_locked(nlrule, ops, tb, extack); if (err) goto errout_free; |