[PATCH linux-6.1.y linux-6.6.y linux-6.12.y 1/1] ndisc: ndisc_send_redirect() cleanup
From: Li Xiasong <hidden>
Date: 2026-08-24 13:18:07
Also in:
lkml, stable
Subsystem:
networking [general], networking [ipv4/ipv6], the rest · Maintainers:
"David S. Miller", Eric Dumazet, Jakub Kicinski, Paolo Abeni, David Ahern, Ido Schimmel, Linus Torvalds
From: Eric Dumazet <edumazet@google.com> [ Upstream commit 0784d83df3bfc977c13252a0599be924f0afa68d ] ndisc_send_redirect() is always called under rcu_read_lock(). It can use dev_net_rcu() and avoid one redundant rcu_read_lock()/rcu_read_unlock() pair. Signed-off-by: Eric Dumazet <edumazet@google.com> Reviewed-by: David Ahern <dsahern@kernel.org> Link: https://patch.msgid.link/20250214140705.2105890-1-edumazet@google.com Signed-off-by: Jakub Kicinski <kuba@kernel.org> Signed-off-by: Li Xiasong <redacted> --- net/ipv6/ndisc.c | 8 +++----- 1 file changed, 3 insertions(+), 5 deletions(-)
diff --git a/net/ipv6/ndisc.c b/net/ipv6/ndisc.c
index 585a9135cf26..7d703a66c0a3 100644
--- a/net/ipv6/ndisc.c
+++ b/net/ipv6/ndisc.c@@ -1671,7 +1671,7 @@ static void ndisc_fill_redirect_hdr_option(struct sk_buff *skb, void ndisc_send_redirect(struct sk_buff *skb, const struct in6_addr *target) { struct net_device *dev = skb->dev; - struct net *net = dev_net(dev); + struct net *net = dev_net_rcu(dev); struct sock *sk = net->ipv6.ndisc_sk; int optlen = 0; struct inet_peer *peer;
@@ -1686,8 +1686,8 @@ void ndisc_send_redirect(struct sk_buff *skb, const struct in6_addr *target) ops_data_buf[NDISC_OPS_REDIRECT_DATA_SPACE], *ops_data = NULL; bool ret; - if (netif_is_l3_master(skb->dev)) { - dev = dev_get_by_index_rcu(dev_net(skb->dev), IPCB(skb)->iif); + if (netif_is_l3_master(dev)) { + dev = dev_get_by_index_rcu(net, IPCB(skb)->iif); if (!dev) return; }
@@ -1725,12 +1725,10 @@ void ndisc_send_redirect(struct sk_buff *skb, const struct in6_addr *target) goto release; } - rcu_read_lock(); peer = inet_getpeer_v6(net->ipv6.peers, &ipv6_hdr(skb)->saddr); if (!peer) goto release; ret = inet_peer_xrlim_allow(peer, 1*HZ); - rcu_read_unlock(); if (!ret) goto release;
--
2.34.1