diff --git a/fs/cifs/cifsencrypt.c b/fs/cifs/cifsencrypt.c
index 259991bd2112..e76bfeb68267 100644
--- a/fs/cifs/cifsencrypt.c
+++ b/fs/cifs/cifsencrypt.c
@@ -87,9 +87,15 @@ int cifs_sign_smb(struct smb_hdr *cifs_pdu, struct TCP_Server_Info *server,
 	if ((cifs_pdu == NULL) || (server == NULL))
 		return -EINVAL;
 
-	if ((cifs_pdu->Flags2 & SMBFLG2_SECURITY_SIGNATURE) == 0)
+	if (!(cifs_pdu->Flags2 & SMBFLG2_SECURITY_SIGNATURE) ||
+	    server->tcpStatus == CifsNeedNegotiate)
 		return rc;
 
+	if (!server->session_estab) {
+		strncpy(cifs_pdu->Signature.SecuritySignature, "BSRSPYL", 8);
+		return rc;
+	}
+
 	cifs_pdu->Signature.Sequence.SequenceNumber =
 			cpu_to_le32(server->sequence_number);
 	cifs_pdu->Signature.Sequence.Reserved = 0;
@@ -178,9 +184,15 @@ int cifs_sign_smb2(struct kvec *iov, int n_vec, struct TCP_Server_Info *server,
 	if ((cifs_pdu == NULL) || (server == NULL))
 		return -EINVAL;
 
-	if ((cifs_pdu->Flags2 & SMBFLG2_SECURITY_SIGNATURE) == 0)
+	if (!(cifs_pdu->Flags2 & SMBFLG2_SECURITY_SIGNATURE) ||
+	    server->tcpStatus == CifsNeedNegotiate)
 		return rc;
 
+	if (!server->session_estab) {
+		strncpy(cifs_pdu->Signature.SecuritySignature, "BSRSPYL", 8);
+		return rc;
+	}
+
 	cifs_pdu->Signature.Sequence.SequenceNumber =
 				cpu_to_le32(server->sequence_number);
 	cifs_pdu->Signature.Sequence.Reserved = 0;