Subject: Re: [PATCH net 1/2] ipv6: Fix route replacement with dev-only route

From: Benjamin Poirier <[email-masked]>
Date: Mon, 17 Feb 2020 12:12:23 +0900

On 2020/02/15 11:00 -0700, David Ahern wrote:
[...]
> 
> Thanks for adding a test case. I take this to mean that all existing
> tests pass with this change. We have found this code to be extremely
> sensitive to seemingly obvious changes.

I saw two failures from that test suite, regardless of this change:

IPv4 rp_filter tests
    TEST: rp_filter passes local packets                                [FAIL]
    TEST: rp_filter passes loopback packets                             [FAIL]

The other tests, including the ipv6_rt group of tests, are OK.

The rp_filter tests fail for me even if I build a kernel from commit
adb701d6cfa4 ("selftests: add a test case for rp_filter")

Running the first ping manually, tcpdump shows:
root@vsid:~# tcpdump -nepi lo
tcpdump: verbose output suppressed, use -v or -vv for full protocol decode
listening on lo, link-type EN10MB (Ethernet), capture size 262144 bytes
12:01:12.618623 52:54:00:6a:c7:5e > 52:54:00:6a:c7:5e, ethertype IPv4 (0x0800), length 98: 198.51.100.1 > 198.51.100.1: ICMP echo request, id 616, seq 435, length 64
12:01:12.618650 52:54:00:6a:c7:5e > 52:54:00:6a:c7:5e, ethertype IPv4 (0x0800), length 98: 198.51.100.1 > 198.51.100.1: ICMP echo reply, id 616, seq 435, length 64

`ping` doesn't show any replies (since it's bound to dummy1...?).

Cong?