cifs: print error code if smb signature verification fails

While trying to debug a SMB signature related issue with Windows Servers
figured out it might be easier to debug if we print the error code from
cifs_verify_signature(). Also, fix indendation while at it.

Signed-off-by: Suresh Jayaraman <sjayaraman@suse.com>
Reviewed-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <smfrench@gmail.com>

fs/cifs/cifssmb.c

@@ -1576,9 +1576,14 @@ cifs_readv_callback(struct mid_q_entry *mid)
 		/* result already set, check signature */
 		if (server->sec_mode &
 		    (SECMODE_SIGN_REQUIRED | SECMODE_SIGN_ENABLED)) {
-			if (cifs_verify_signature(rdata->iov, rdata->nr_iov,
-					  server, mid->sequence_number + 1))
-				cERROR(1, "Unexpected SMB signature");
+			int rc = 0;
+
+			rc = cifs_verify_signature(rdata->iov, rdata->nr_iov,
+						   server,
+						   mid->sequence_number + 1);
+			if (rc)
+				cERROR(1, "SMB signature verification returned "
+				       "error = %d", rc);
 		}
 		/* FIXME: should this be counted toward the initiating task? */
 		task_io_account_read(rdata->bytes);

fs/cifs/transport.c

@@ -503,13 +503,16 @@ cifs_check_receive(struct mid_q_entry *mid, struct TCP_Server_Info *server,
 	/* convert the length into a more usable form */
 	if (server->sec_mode & (SECMODE_SIGN_REQUIRED | SECMODE_SIGN_ENABLED)) {
 		struct kvec iov;
+		int rc = 0;
 
 		iov.iov_base = mid->resp_buf;
 		iov.iov_len = len;
 		/* FIXME: add code to kill session */
-		if (cifs_verify_signature(&iov, 1, server,
-					  mid->sequence_number + 1) != 0)
-			cERROR(1, "Unexpected SMB signature");
+		rc = cifs_verify_signature(&iov, 1, server,
+					   mid->sequence_number + 1);
+		if (rc)
+			cERROR(1, "SMB signature verification returned error = "
+			       "%d", rc);
 	}
 
 	/* BB special case reconnect tid and uid here? */