diff --git a/net/core/pktgen.c b/net/core/pktgen.c
index f56b8d697014..48306a101fd9 100644
--- a/net/core/pktgen.c
+++ b/net/core/pktgen.c
@@ -1318,9 +1318,10 @@ static ssize_t pktgen_if_write(struct file *file,
 		return count;
 	}
 	if (!strcmp(name, "flag")) {
+		bool disable = false;
 		__u32 flag;
 		char f[32];
-		bool disable = false;
+		char *end;
 
 		memset(f, 0, 32);
 		len = strn_len(&user_buffer[i], sizeof(f) - 1);
@@ -1332,28 +1333,33 @@ static ssize_t pktgen_if_write(struct file *file,
 		i += len;
 
 		flag = pktgen_read_flag(f, &disable);
-
 		if (flag) {
 			if (disable)
 				pkt_dev->flags &= ~flag;
 			else
 				pkt_dev->flags |= flag;
-		} else {
-			sprintf(pg_result,
-				"Flag -:%s:- unknown\nAvailable flags, (prepend ! to un-set flag):\n%s",
-				f,
-				"IPSRC_RND, IPDST_RND, UDPSRC_RND, UDPDST_RND, "
-				"MACSRC_RND, MACDST_RND, TXSIZE_RND, IPV6, "
-				"MPLS_RND, VID_RND, SVID_RND, FLOW_SEQ, "
-				"QUEUE_MAP_RND, QUEUE_MAP_CPU, UDPCSUM, "
-				"NO_TIMESTAMP, "
-#ifdef CONFIG_XFRM
-				"IPSEC, "
-#endif
-				"NODE_ALLOC\n");
+
+			sprintf(pg_result, "OK: flags=0x%x", pkt_dev->flags);
 			return count;
 		}
-		sprintf(pg_result, "OK: flags=0x%x", pkt_dev->flags);
+
+		/* Unknown flag */
+		end = pkt_dev->result + sizeof(pkt_dev->result);
+		pg_result += sprintf(pg_result,
+			"Flag -:%s:- unknown\n"
+			"Available flags, (prepend ! to un-set flag):\n", f);
+
+		for (int n = 0; n < NR_PKT_FLAGS && pg_result < end; n++) {
+			if (!IS_ENABLED(CONFIG_XFRM) && n == IPSEC_SHIFT)
+				continue;
+			pg_result += snprintf(pg_result, end - pg_result,
+					      "%s, ", pkt_flag_names[n]);
+		}
+		if (!WARN_ON_ONCE(pg_result >= end)) {
+			/* Remove the comma and whitespace at the end */
+			*(pg_result - 2) = '\0';
+		}
+
 		return count;
 	}
 	if (!strcmp(name, "dst_min") || !strcmp(name, "dst")) {