[PATCH v2] net: airoha: Fix debugfs new-tuple display for IPv4 ROUTE entries

["Wayen.Yan" <win847@gmail.com>]

In airoha_ppe_debugfs_foe_show(), the second switch statement falls
through from PPE_PKT_TYPE_IPV4_HNAPT/DSLITE to PPE_PKT_TYPE_IPV4_ROUTE,
accessing hwe->ipv4.new_tuple for all three types. However, IPv4 ROUTE
(3-tuple) entries do not contain a valid new_tuple — this field is only
meaningful for NATted flows (HNAPT/DSLITE). For ROUTE entries, the
memory at the new_tuple offset holds routing information, not NAT data,
so displaying "new=" produces garbage output.

Display new_tuple only for HNAPT and DSLITE, and let IPV4_ROUTE fall
through to the default case.

Fixes: 3fe15c640f38 ("net: airoha: Introduce PPE debugfs support")
Link: https://lore.kernel.org/netdev/6a2b40ea.4dd82583.3a5c46.e5a2@mx.google.com/
Signed-off-by: Wayen.Yan <win847@gmail.com>
- Drop redundant PPE_PKT_TYPE_IPV4_ROUTE case, let it fall to default
Changes in v2:

---
 drivers/net/ethernet/airoha/airoha_ppe_debugfs.c | 2 --
 1 file changed, 2 deletions(-)

diff --git a/drivers/net/ethernet/airoha/airoha_ppe_debugfs.c b/drivers/net/ethernet/airoha/airoha_ppe_debugfs.c
index 0112c41..e46a985 100644
--- a/drivers/net/ethernet/airoha/airoha_ppe_debugfs.c
+++ b/drivers/net/ethernet/airoha/airoha_ppe_debugfs.c
@@ -121,8 +121,6 @@ static int airoha_ppe_debugfs_foe_show(struct seq_file *m, void *private,
 		case PPE_PKT_TYPE_IPV4_DSLITE:
 			src_port = &hwe->ipv4.new_tuple.src_port;
 			dest_port = &hwe->ipv4.new_tuple.dest_port;
-			fallthrough;
-		case PPE_PKT_TYPE_IPV4_ROUTE:
 			src_addr = &hwe->ipv4.new_tuple.src_ip;
 			dest_addr = &hwe->ipv4.new_tuple.dest_ip;
 			seq_puts(m, " new=");
-- 
2.51.0