netdev - [PATCH net 6/6] selftests: netfilter: disable rp

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Date:   Fri, 11 Feb 2022 00:10:21 +0100
From:   Pablo Neira Ayuso <pablo@...filter.org>
To:     netfilter-devel@...r.kernel.org
Cc:     davem@...emloft.net, netdev@...r.kernel.org, kuba@...nel.org
Subject: [PATCH net 6/6] selftests: netfilter: disable rp_filter on router

From: Hangbin Liu <liuhangbin@...il.com>

Some distros may enable rp_filter by default. After ns1 change addr to
10.0.2.99 and set default router to 10.0.2.1, while the connected router
address is still 10.0.1.1. The router will not reply the arp request
from ns1. Fix it by setting the router's veth0 rp_filter to 0.

Before the fix:
  # ./nft_fib.sh
  PASS: fib expression did not cause unwanted packet drops
  Netns nsrouter-HQkDORO2 fib counter doesn't match expected packet count of 1 for 1.1.1.1
  table inet filter {
          chain prerouting {
                  type filter hook prerouting priority filter; policy accept;
                  ip daddr 1.1.1.1 fib saddr . iif oif missing counter packets 0 bytes 0 drop
                  ip6 daddr 1c3::c01d fib saddr . iif oif missing counter packets 0 bytes 0 drop
          }
  }

After the fix:
  # ./nft_fib.sh
  PASS: fib expression did not cause unwanted packet drops
  PASS: fib expression did drop packets for 1.1.1.1
  PASS: fib expression did drop packets for 1c3::c01d

Fixes: 82944421243e ("selftests: netfilter: add fib test case")
Signed-off-by: Yi Chen <yiche@...hat.com>
Signed-off-by: Hangbin Liu <liuhangbin@...il.com>
Signed-off-by: Pablo Neira Ayuso <pablo@...filter.org>
---
 tools/testing/selftests/netfilter/nft_fib.sh | 1 +
 1 file changed, 1 insertion(+)

diff --git a/tools/testing/selftests/netfilter/nft_fib.sh b/tools/testing/selftests/netfilter/nft_fib.sh
index 6caf6ac8c285..695a1958723f 100755
--- a/tools/testing/selftests/netfilter/nft_fib.sh
+++ b/tools/testing/selftests/netfilter/nft_fib.sh
@@ -174,6 +174,7 @@ test_ping() {
 ip netns exec ${nsrouter} sysctl net.ipv6.conf.all.forwarding=1 > /dev/null
 ip netns exec ${nsrouter} sysctl net.ipv4.conf.veth0.forwarding=1 > /dev/null
 ip netns exec ${nsrouter} sysctl net.ipv4.conf.veth1.forwarding=1 > /dev/null
+ip netns exec ${nsrouter} sysctl net.ipv4.conf.veth0.rp_filter=0 > /dev/null
 
 sleep 3
 
-- 
2.30.2