--- a/fdtput.c	2026-08-15 15:43:04.550373900 +0200
+++ b/fdtput.c	2026-08-15 16:02:11.926917822 +0200
@@ -410,7 +410,7 @@ static int do_fdtput(struct display_info
 	uint32_t dt_total = 0;
 	uint32_t page_size = 0;
 	uint32_t fdt_addr = 0;
-	int fdt_count = 0;
+	int fdt_target_id = -1;
 	char **fdts = NULL;
 	char *fdt;
 	char amlogic_dt_id[256] = {0};
@@ -452,20 +452,22 @@ static int do_fdtput(struct display_info
 					int tmp_node;
 					const struct fdt_property *dt_id = NULL;
 					tmp_node = fdt_path_offset(blob + tmp_fdt_addr, "/");
-					if (tmp_node >= 0)
+					if (tmp_node >= 0) {
 						dt_id = fdt_getprop(blob + tmp_fdt_addr, tmp_node, "amlogic-dt-id", &len);
+						len--; // include nul ?
+					}
 
 					// check if correct dtb in multidtb got found
 					if (dt_id &&
-							(len >= strlen(amlogic_dt_id)) &&
+							(len == strlen(amlogic_dt_id)) &&
 							(!strncmp((const char *)dt_id, amlogic_dt_id, strlen(amlogic_dt_id)))) {
 						fdt_addr = tmp_fdt_addr;
+						fdt_target_id = i;
 					}
 					// make a backup and leave the dtb untouched
 					else if (fdts) {
-						fdts[fdt_count] = xmalloc(tmp_fdt_size);
-						memcpy(fdts[fdt_count], blob + tmp_fdt_addr, tmp_fdt_size);
-						fdt_count++;
+						fdts[i] = xmalloc(tmp_fdt_size);
+						memcpy(fdts[i], blob + tmp_fdt_addr, tmp_fdt_size);
 					}
 				}
 			}
@@ -531,9 +533,12 @@ static int do_fdtput(struct display_info
 		// add single dtb to multidtb before save to file
 		// free memory allocated before
 		fdt_size = fdt_totalsize(blob);
-		if (fdts) {
-			fdts[fdt_count] = xmalloc(fdt_size);
-			memcpy(fdts[fdt_count], blob, fdt_size);
+		if (fdts && fdt_target_id >= 0) {
+			if (fdts[fdt_target_id])
+				free(fdts[fdt_target_id]);
+			
+			fdts[fdt_target_id] = xmalloc(fdt_size);
+			memcpy(fdts[fdt_target_id], blob, fdt_size);
 			free(blob);
 			blob = fdt;
 			create_multidtb(&blob, dt_total, page_size, fdts);
@@ -547,8 +552,11 @@ static int do_fdtput(struct display_info
 	}
 
 	if (fdts) {
-		for (i = 0; i < (dt_total - 1); i++)
-			free(fdts[i]);
+		for (i = 0; i < (dt_total - 1); i++) {
+			if (fdts[i])
+				free(fdts[i]);
+		}
+
 		free(fdts);
 	}
 	free(blob);