diff --git a/arch/s390/mm/cmm.c b/arch/s390/mm/cmm.c
index 4bddf8d..a9550dc 100644
--- a/arch/s390/mm/cmm.c
+++ b/arch/s390/mm/cmm.c
@@ -435,6 +435,13 @@
 	if (!cmm_sysctl_header)
 		goto out_sysctl;
 #ifdef CONFIG_CMM_IUCV
+	/* convert sender to uppercase characters */
+	if (sender) {
+		int len = strlen(sender);
+		while (len--)
+			sender[len] = toupper(sender[len]);
+	}
+
 	rc = smsg_register_callback(SMSG_PREFIX, cmm_smsg_target);
 	if (rc < 0)
 		goto out_smsg;
diff --git a/drivers/s390/net/smsgiucv_app.c b/drivers/s390/net/smsgiucv_app.c
index 1376887..4d2ea40 100644
--- a/drivers/s390/net/smsgiucv_app.c
+++ b/drivers/s390/net/smsgiucv_app.c
@@ -180,6 +180,13 @@
 		goto fail_put_driver;
 	}
 
+	/* convert sender to uppercase characters */
+	if (sender) {
+		int len = strlen(sender);
+		while (len--)
+			sender[len] = toupper(sender[len]);
+	}
+
 	/* register with the smsgiucv device driver */
 	rc = smsg_register_callback(SMSG_PREFIX, smsg_app_callback);
 	if (rc) {