CIFS: Move RFC1002 check to a separate function (98bac62c) · Commits · e / devices / android_kernel_xiaomi_markw

fs/cifs/connect.c

+67 −49

Original line number	Diff line number	Diff line
		@@ -416,6 +416,63 @@ read_from_socket(struct TCP_Server_Info server, struct msghdr smb_msg,
		return rc;
		}

		static bool
		check_rfc1002_header(struct TCP_Server_Info server, char buf)
		{
		char temp = *buf;
		unsigned int pdu_length = be32_to_cpu(
		((struct smb_hdr *)buf)->smb_buf_length);

		/*
		* The first byte big endian of the length field,
		* is actually not part of the length but the type
		* with the most common, zero, as regular data.
		*/
		if (temp == (char) RFC1002_SESSION_KEEP_ALIVE) {
		return false;
		} else if (temp == (char)RFC1002_POSITIVE_SESSION_RESPONSE) {
		cFYI(1, "Good RFC 1002 session rsp");
		return false;
		} else if (temp == (char)RFC1002_NEGATIVE_SESSION_RESPONSE) {
		/*
		* We get this from Windows 98 instead of an error on
		* SMB negprot response.
		*/
		cFYI(1, "Negative RFC1002 Session Response Error 0x%x)",
		pdu_length);
		/* give server a second to clean up */
		msleep(1000);
		/*
		* Always try 445 first on reconnect since we get NACK
		* on some if we ever connected to port 139 (the NACK
		* is since we do not begin with RFC1001 session
		* initialize frame).
		*/
		cifs_set_port((struct sockaddr *)
		&server->dstaddr, CIFS_PORT);
		cifs_reconnect(server);
		wake_up(&server->response_q);
		return false;
		} else if (temp != (char) 0) {
		cERROR(1, "Unknown RFC 1002 frame");
		cifs_dump_mem(" Received Data: ", buf, 4);
		cifs_reconnect(server);
		return false;
		}

		/* else we have an SMB response */
		if ((pdu_length > CIFSMaxBufSize + MAX_CIFS_HDR_SIZE - 4) \|\|
		(pdu_length < sizeof(struct smb_hdr) - 1 - 4)) {
		cERROR(1, "Invalid size SMB length %d pdu_length %d",
		4, pdu_length+4);
		cifs_reconnect(server);
		wake_up(&server->response_q);
		return false;
		}

		return true;
		}

		static int
		cifs_demultiplex_thread(void *p)
		{
		@@ -429,7 +486,6 @@ cifs_demultiplex_thread(void *p)
		struct list_head tmp, tmp2;
		struct task_struct *task_to_wake = NULL;
		struct mid_q_entry *mid_entry;
		char temp;
		bool isLargeBuf = false;
		bool isMultiRsp;
		int rc;
		@@ -482,59 +538,21 @@ incomplete_rcv:
		else if (rc == 1)
		continue;

		/* The right amount was read from socket - 4 bytes */
		/* so we can now interpret the length field */

		/* the first byte big endian of the length field,
		is actually not part of the length but the type
		with the most common, zero, as regular data */
		temp = *buf;
		/*
		* The right amount was read from socket - 4 bytes,
		* so we can now interpret the length field.
		*/

		/* Note that FC 1001 length is big endian on the wire,
		but we convert it here so it is always manipulated
		as host byte order */
		/*
		* Note that RFC 1001 length is big endian on the wire,
		* but we convert it here so it is always manipulated
		* as host byte order.
		*/
		pdu_length = be32_to_cpu(smb_buffer->smb_buf_length);

		cFYI(1, "rfc1002 length 0x%x", pdu_length+4);

		if (temp == (char) RFC1002_SESSION_KEEP_ALIVE) {
		continue;
		} else if (temp == (char)RFC1002_POSITIVE_SESSION_RESPONSE) {
		cFYI(1, "Good RFC 1002 session rsp");
		continue;
		} else if (temp == (char)RFC1002_NEGATIVE_SESSION_RESPONSE) {
		/* we get this from Windows 98 instead of
		an error on SMB negprot response */
		cFYI(1, "Negative RFC1002 Session Response Error 0x%x)",
		pdu_length);
		/* give server a second to clean up */
		msleep(1000);
		/* always try 445 first on reconnect since we get NACK
		* on some if we ever connected to port 139 (the NACK
		* is since we do not begin with RFC1001 session
		* initialize frame)
		*/
		cifs_set_port((struct sockaddr *)
		&server->dstaddr, CIFS_PORT);
		cifs_reconnect(server);
		wake_up(&server->response_q);
		continue;
		} else if (temp != (char) 0) {
		cERROR(1, "Unknown RFC 1002 frame");
		cifs_dump_mem(" Received Data: ", buf, length);
		cifs_reconnect(server);
		if (!check_rfc1002_header(server, buf))
		continue;
		}

		/* else we have an SMB response */
		if ((pdu_length > CIFSMaxBufSize + MAX_CIFS_HDR_SIZE - 4) \|\|
		(pdu_length < sizeof(struct smb_hdr) - 1 - 4)) {
		cERROR(1, "Invalid size SMB length %d pdu_length %d",
		length, pdu_length+4);
		cifs_reconnect(server);
		wake_up(&server->response_q);
		continue;
		}

		/* else length ok */
		if (pdu_length > MAX_CIFS_SMALL_BUFFER_SIZE - 4) {