[PATCH 4.19 27/86] ipv6_tunnel: Rate limit warning messages

Greg Kroah-Hartman
2022-02-07T11:19:59Z

From: Ido Schimmel <idosch@nvidia.com>

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>
---
net/ipv6/ip6_tunnel.c | 8 ++++----
1 file changed, 4 insertions(+), 4 deletions(-)

--- a/net/ipv6/ip6_tunnel.c
+++ b/net/ipv6/ip6_tunnel.c
@@ -1005,14 +1005,14 @@ 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();