[PATCH 5.15 10/13] selftests: mptcp: join: fix "invalid address, ADD_ADDR timeout"

[Greg Kroah-Hartman <gregkh@linuxfoundation.org>]

From: Matthieu Baerts <matthieu.baerts@tessares.net>

The "Fixes" commit mentioned below adds new MIBs counters to track some
particular cases that have been fixed by its parent commit 150d1e06c4f1
("mptcp: fix race in incoming ADD_ADDR option processing").

Unfortunately, one of the new MIB counter (AddAddrDrop) shares the same
prefix as an older one (AddAddr). This breaks one selftest because it
was doing a grep on "AddAddr" and it now gets 2 counters instead of 1.

This issue has been fixed upstream in a commit that was part of the same
set but not backported to v5.15, see commit 6ef84b1517e0 ("selftests:
mptcp: more robust signal race test"). It has not been backported
because it was fixing multiple things, some where for >v5.15.

This patch then simply extracts the only bit needed for v5.15. Now the
test passes when validating the last stable v5.15 kernel.

Fixes: f25ae162f4b3 ("mptcp: add mibs counter for ignored incoming options")
Signed-off-by: Matthieu Baerts <matthieu.baerts@tessares.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
 tools/testing/selftests/net/mptcp/mptcp_join.sh |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

--- a/tools/testing/selftests/net/mptcp/mptcp_join.sh
+++ b/tools/testing/selftests/net/mptcp/mptcp_join.sh
@@ -732,7 +732,7 @@ chk_add_nr()
 	local dump_stats
 
 	printf "%-39s %s" " " "add"
-	count=`ip netns exec $ns2 nstat -as | grep MPTcpExtAddAddr | awk '{print $2}'`
+	count=`ip netns exec $ns2 nstat -as MPTcpExtAddAddr | grep MPTcpExtAddAddr | awk '{print $2}'`
 	[ -z "$count" ] && count=0
 	if [ "$count" != "$add_nr" ]; then
 		echo "[fail] got $count ADD_ADDR[s] expected $add_nr"