selftests: net: more pmtu.sh fixes

The netdev CI is reporting failures for the pmtu test:

  [  115.929264] br0: port 2(vxlan_a) entered forwarding state
  # 2024/02/08 17:33:22 socat[7871] E bind(7, {AF=10 [0000:0000:0000:0000:0000:0000:0000:0000]:50000}, 28): Address already in use
  # 2024/02/08 17:33:22 socat[7877] E write(7, 0x5598fb6ff000, 8192): Connection refused
  # TEST: IPv6, bridged vxlan4: PMTU exceptions                         [FAIL]
  # File size 0 mismatches exepcted value in locally bridged vxlan test

The root cause is apparently a socket created by a previous iteration
of the relevant loop still lasting in LAST_ACK state.

Note that even the file size check is racy, the receiver process dumping
the file could still be running in background

Allow the listener to bound on the same local port via SO_REUSEADDR and
collect file output file size only after the listener completion.

Fixes: 136a1b434b ("selftests: net: test vxlan pmtu exceptions with tcp")
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Link: https://lore.kernel.org/r/4f51c11a1ce7ca7a4dabd926cffff63dadac9ba1.1707731086.git.pabeni@redhat.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
This commit is contained in:
Paolo Abeni 2024-02-12 11:19:24 +01:00 committed by Jakub Kicinski
parent a71d0908e3
commit 20622dc934

View File

@ -1336,16 +1336,16 @@ test_pmtu_ipvX_over_bridged_vxlanY_or_geneveY_exception() {
else
TCPDST="TCP:[${dst}]:50000"
fi
${ns_b} socat -T 3 -u -6 TCP-LISTEN:50000 STDOUT > $tmpoutfile &
${ns_b} socat -T 3 -u -6 TCP-LISTEN:50000,reuseaddr STDOUT > $tmpoutfile &
local socat_pid=$!
wait_local_port_listen ${NS_B} 50000 tcp
dd if=/dev/zero status=none bs=1M count=1 | ${target} socat -T 3 -u STDIN $TCPDST,connect-timeout=3
wait ${socat_pid}
size=$(du -sb $tmpoutfile)
size=${size%%/tmp/*}
wait ${socat_pid}
[ $size -ne 1048576 ] && err "File size $size mismatches exepcted value in locally bridged vxlan test" && return 1
done