From 9c5cbc030ffcd683cf61c7aef8e7995a2b4848d8 Mon Sep 17 00:00:00 2001
From: Amin Ben Romdhane <amin.benromdhane@iopsys.eu>
Date: Tue, 23 Apr 2024 03:41:56 +0000
Subject: [PATCH] IP.Interface: setting 'mtu' option in device section instead
 of interface section

---
 libbbfdm/dmtree/tr181/ip.c | 17 ++++++++++++++++-
 1 file changed, 16 insertions(+), 1 deletion(-)

diff --git a/libbbfdm/dmtree/tr181/ip.c b/libbbfdm/dmtree/tr181/ip.c
index e3a7ffcd..830b748c 100644
--- a/libbbfdm/dmtree/tr181/ip.c
+++ b/libbbfdm/dmtree/tr181/ip.c
@@ -1438,13 +1438,28 @@ static int get_IPInterface_MaxMTUSize(char *refparam, struct dmctx *ctx, void *d
 
 static int set_IPInterface_MaxMTUSize(char *refparam, struct dmctx *ctx, void *data, char *instance, char *value, int action)
 {
+	char *device = NULL;
+	struct uci_section *s = NULL;
+
 	switch (action)	{
 		case VALUECHECK:
 			if (bbfdm_validate_unsignedInt(ctx, value, RANGE_ARGS{{"64","65535"}}, 1))
 				return FAULT_9007;
 			break;
 		case VALUESET:
-			dmuci_set_value_by_section((struct uci_section *)data, "mtu", value);
+			/* find the device section for this interface */
+			dmuci_get_value_by_section_string((struct uci_section *)data, "device", &device);
+
+			/* check if device is empty */
+			if ((device)[0] == '\0') {
+				return FAULT_9002;
+			}
+
+			/* set option MTU in device section */
+			uci_foreach_option_eq("network", "device", "name", device, s) {
+				dmuci_set_value_by_section(s, "mtu", value);
+				break;
+			}
 			break;
 	}
 	return 0;