smb3: add indatalen that can be a non-zero value to calculation of credit charge in smb2 ioctl

Some of tests in xfstests failed with cifsd kernel server since commit
e80ddeb. cifsd kernel server validates credit charge from client
by calculating it base on max((InputCount + OutputCount) and
(MaxInputResponse + MaxOutputResponse)) according to specification.

MS-SMB2 specification describe credit charge calculation of smb2 ioctl :

If Connection.SupportsMultiCredit is TRUE, the server MUST validate
CreditCharge based on the maximum of (InputCount + OutputCount) and
(MaxInputResponse + MaxOutputResponse), as specified in section 3.3.5.2.5.
If the validation fails, it MUST fail the IOCTL request with
STATUS_INVALID_PARAMETER.

This patch add indatalen that can be a non-zero value to calculation of
credit charge in SMB2_ioctl_init().

Fixes: e80ddeb ("smb3: fix incorrect number of credits when ioctl
MaxOutputResponse > 64K")
Cc: Stable <[email protected]>
Reviewed-by: Aurelien Aptel <[email protected]>
Cc: Steve French <[email protected]>
Signed-off-by: Namjae Jeon <[email protected]>
Signed-off-by: Steve French <[email protected]>

Author: namjaejeon

fs/cifs/smb2pdu.c

@@ -2973,7 +2973,9 @@ SMB2_ioctl_init(struct cifs_tcon *tcon, struct TCP_Server_Info *server,
 	 * response size smaller.
 	 */
 	req->MaxOutputResponse = cpu_to_le32(max_response_size);
-	req->sync_hdr.CreditCharge = cpu_to_le16(DIV_ROUND_UP(max_response_size, SMB2_MAX_BUFFER_SIZE));
+	req->sync_hdr.CreditCharge =
+		cpu_to_le16(DIV_ROUND_UP(max(indatalen, max_response_size),
+					 SMB2_MAX_BUFFER_SIZE));
 	if (is_fsctl)
 		req->Flags = cpu_to_le32(SMB2_0_IOCTL_IS_FSCTL);
 	else