ndisc: ndisc_send_redirect() must use dev_get_by_index_rcu()

[ Upstream commit 48145a57d4bbe3496e8e4880b23ea6b511e6e519 ]

ndisc_send_redirect() is called under RCU protection, not RTNL.

It must use dev_get_by_index_rcu() instead of __dev_get_by_index()

Fixes: 2f17becfbea5 ("vrf: check the original netdevice for generating redirect")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Stephen Suryaputra <ssuryaextr@gmail.com>
Reviewed-by: David Ahern <dsahern@kernel.org>
Reviewed-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Link: https://patch.msgid.link/20250207135841.1948589-2-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>

diff --git a/net/ipv6/ndisc.c b/net/ipv6/ndisc.c
index 44d3e6ab0c7d4f9b270c38e016fc85b19a27092a..6df3f4aadf641b5d6d40fbd3f6cf366beef54c1c 100644 (file)
--- a/net/ipv6/ndisc.c
+++ b/net/ipv6/ndisc.c
@@ -1684,7 +1684,7 @@ void ndisc_send_redirect(struct sk_buff *skb, const struct in6_addr *target)
        bool ret;
 
        if (netif_is_l3_master(skb->dev)) {
-               dev = __dev_get_by_index(dev_net(skb->dev), IPCB(skb)->iif);
+               dev = dev_get_by_index_rcu(dev_net(skb->dev), IPCB(skb)->iif);
                if (!dev)
                        return;
        }