ipv6_tunnel: Rate limit warning messages

BugLink: https://bugs.launchpad.net/bugs/1959879
commit 6cee105e7f2ced596373951d9ea08dacc3883c68 upstream.

The warning messages can be invoked from the data path for every packet
transmitted through an ip6gre netdev, leading to high CPU utilization.

Fix that by rate limiting the messages.

Fixes: 09c6bbf090ec ("[IPV6]: Do mandatory IPv6 tunnel endpoint checks in realtime")
Reported-by: Maksym Yaremchuk <maksymy@nvidia.com>
Tested-by: Maksym Yaremchuk <maksymy@nvidia.com>
Signed-off-by: Ido Schimmel <idosch@nvidia.com>
Reviewed-by: Amit Cohen <amcohen@nvidia.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Signed-off-by: Paolo Pisati <paolo.pisati@canonical.com>

diff --git a/net/ipv6/ip6_tunnel.c b/net/ipv6/ip6_tunnel.c
index 20a67efda47f520578f9cb09ad2d3f2609b6d62d..fa8da8ff35b42f18c9574975f28b5476c0187607 100644 (file)
--- a/net/ipv6/ip6_tunnel.c
+++ b/net/ipv6/ip6_tunnel.c
@@ -1036,14 +1036,14 @@ int ip6_tnl_xmit_ctl(struct ip6_tnl *t,
 
                if (unlikely(!ipv6_chk_addr_and_flags(net, laddr, ldev, false,
                                                      0, IFA_F_TENTATIVE)))
-                       pr_warn("%s xmit: Local address not yet configured!\n",
-                               p->name);
+                       pr_warn_ratelimited("%s xmit: Local address not yet configured!\n",
+                                           p->name);
                else if (!(p->flags & IP6_TNL_F_ALLOW_LOCAL_REMOTE) &&
                         !ipv6_addr_is_multicast(raddr) &&
                         unlikely(ipv6_chk_addr_and_flags(net, raddr, ldev,
                                                          true, 0, IFA_F_TENTATIVE)))
-                       pr_warn("%s xmit: Routing loop! Remote address found on this node!\n",
-                               p->name);
+                       pr_warn_ratelimited("%s xmit: Routing loop! Remote address found on this node!\n",
+                                           p->name);
                else
                        ret = 1;
                rcu_read_unlock();