747c143 caused icmp redirect to fail

[Heng Qi]

The detailed description: When testing with selftests/net/icmp_redirect.sh, a redirect exception FAIL occurred for IPv4.
This is not in line with actual expectations. r1 changes the route to the destination network 172.16.2.0/24 from 10.1.1.2 to 172.16.1.254. After h1 sends the ping packet, h1 continues to obtain the route to 172.16.2.2, and the result is not as expected.
This flaw was introduced by 747c14307214b55dbd8250e1ab44cad8305756f1. When this commit is rolled back, the test will pass.

bug commit: 747c14307214b55dbd8250e1ab44cad8305756f1

Anolis bugzilla link: https://bugzilla.openanolis.cn/show_bug.cgi?id=1843

uname -mi: aarch64 aarch64

uname -r: 6.0.0-rc2-00159-g4c612826bec1

cat /proc/version: Linux version 6.0.0-rc2-00159-g4c612826bec1 (root@iZbp1abkyymykg1xs81hoeZ) (gcc (GCC) 8.5.0 20210514 (Anolis 8.5.0-10.0.1), GNU ld version 2.30-113.0.1.an8)

#!/bin/bash
# SPDX-License-Identifier: GPL-2.0
#
# redirect test
#
#                     .253 +----+
#                     +----| r1 |
#                     |    +----+
# +----+              |       |.1
# | h1 |--------------+       |   10.1.1.0/30 2001:db8:1::0/126
# +----+ .1           |       |.2
#         172.16.1/24 |    +----+                   +----+
#    2001:db8:16:1/64 +----| r2 |-------------------| h2 |
#                     .254 +----+ .254           .2 +----+
#                                    172.16.2/24
#                                  2001:db8:16:2/64
#
# Route from h1 to h2 goes through r1, eth1 - connection between r1 and r2.
# Route on r1 changed to go to r2 via eth0. This causes a redirect to be sent
# from r1 to h1 telling h1 to use r2 when talking to h2.


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