[1/2] cifs: remove rfc1002 header from all SMB2 response structures

Message ID 20180121220644.7907-2-lsahlber@redhat.com
State New
Headers show
Series
  • cifs: remove rfc1002 length field from all SMB2 response structures
Related show

Commit Message

Ronnie Sahlberg Jan. 21, 2018, 10:06 p.m.
Separate out all the 4 byte rfc1002 headers so that they are no longer
part of the SMB2 header structures to prepare for future work to add
compounding support.

Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com>
---
 fs/cifs/cifsglob.h      |   2 +
 fs/cifs/cifssmb.c       |   9 ++-
 fs/cifs/connect.c       |  32 ++++++---
 fs/cifs/misc.c          |   2 +-
 fs/cifs/smb1ops.c       |   1 +
 fs/cifs/smb2glob.h      |   5 --
 fs/cifs/smb2maperror.c  |   8 ++-
 fs/cifs/smb2misc.c      | 111 +++++++++++++++---------------
 fs/cifs/smb2ops.c       | 177 ++++++++++++++++++++++++++++++------------------
 fs/cifs/smb2pdu.c       | 105 ++++++++++++++--------------
 fs/cifs/smb2pdu.h       |  65 ++++++------------
 fs/cifs/smb2proto.h     |   5 +-
 fs/cifs/smb2transport.c |   6 +-
 fs/cifs/transport.c     |   4 +-
 14 files changed, 283 insertions(+), 249 deletions(-)

Patch

diff --git a/fs/cifs/cifsglob.h b/fs/cifs/cifsglob.h
index 3fb1a2fe1ea9..14db722c4b0d 100644
--- a/fs/cifs/cifsglob.h
+++ b/fs/cifs/cifsglob.h
@@ -460,6 +460,7 @@  struct smb_version_values {
 	__u32		exclusive_lock_type;
 	__u32		shared_lock_type;
 	__u32		unlock_lock_type;
+	size_t		header_preamble_size;
 	size_t		header_size;
 	size_t		max_header_size;
 	size_t		read_rsp_size;
@@ -656,6 +657,7 @@  struct TCP_Server_Info {
 	struct delayed_work	echo; /* echo ping workqueue job */
 	char	*smallbuf;	/* pointer to current "small" buffer */
 	char	*bigbuf;	/* pointer to current "big" buffer */
+	unsigned int total_size; /* Total size of this PDU */
 	unsigned int total_read; /* total amount of data read in this pass */
 #ifdef CONFIG_CIFS_FSCACHE
 	struct fscache_cookie   *fscache; /* client index cache cookie */
diff --git a/fs/cifs/cifssmb.c b/fs/cifs/cifssmb.c
index 35dc5bf01ee2..114e2a7ca77f 100644
--- a/fs/cifs/cifssmb.c
+++ b/fs/cifs/cifssmb.c
@@ -1453,7 +1453,9 @@  cifs_readv_receive(struct TCP_Server_Info *server, struct mid_q_entry *mid)
 	unsigned int data_offset, data_len;
 	struct cifs_readdata *rdata = mid->callback_data;
 	char *buf = server->smallbuf;
-	unsigned int buflen = get_rfc1002_length(buf) + 4;
+	unsigned int buflen;
+
+	buflen = server->total_size + server->vals->header_preamble_size;
 
 	cifs_dbg(FYI, "%s: mid=%llu offset=%llu bytes=%u\n",
 		 __func__, mid->mid, rdata->offset, rdata->bytes);
@@ -1464,7 +1466,7 @@  cifs_readv_receive(struct TCP_Server_Info *server, struct mid_q_entry *mid)
 	 * the Mid.
 	 */
 	len = min_t(unsigned int, buflen, server->vals->read_rsp_size) -
-							HEADER_SIZE(server) + 1;
+		HEADER_SIZE(server) + 1;
 
 	length = cifs_read_from_socket(server,
 				       buf + HEADER_SIZE(server) - 1, len);
@@ -1502,7 +1504,8 @@  cifs_readv_receive(struct TCP_Server_Info *server, struct mid_q_entry *mid)
 		return cifs_readv_discard(server, mid);
 	}
 
-	data_offset = server->ops->read_data_offset(buf) + 4;
+	data_offset = server->ops->read_data_offset(buf) +
+		server->vals->header_preamble_size;
 	if (data_offset < server->total_read) {
 		/*
 		 * win2k8 sometimes sends an offset of 0 when the read
diff --git a/fs/cifs/connect.c b/fs/cifs/connect.c
index 64be6f9e54a2..18a1cb4f2330 100644
--- a/fs/cifs/connect.c
+++ b/fs/cifs/connect.c
@@ -763,10 +763,11 @@  standard_receive3(struct TCP_Server_Info *server, struct mid_q_entry *mid)
 {
 	int length;
 	char *buf = server->smallbuf;
-	unsigned int pdu_length = get_rfc1002_length(buf);
+	unsigned int pdu_length = server->total_size;
 
 	/* make sure this will fit in a large buffer */
-	if (pdu_length > CIFSMaxBufSize + MAX_HEADER_SIZE(server) - 4) {
+	if (pdu_length > CIFSMaxBufSize + MAX_HEADER_SIZE(server) -
+		server->vals->header_preamble_size) {
 		cifs_dbg(VFS, "SMB response too long (%u bytes)\n", pdu_length);
 		cifs_reconnect(server);
 		wake_up(&server->response_q);
@@ -781,8 +782,11 @@  standard_receive3(struct TCP_Server_Info *server, struct mid_q_entry *mid)
 	}
 
 	/* now read the rest */
-	length = cifs_read_from_socket(server, buf + HEADER_SIZE(server) - 1,
-				pdu_length - HEADER_SIZE(server) + 1 + 4);
+	length = cifs_read_from_socket(server,
+				       buf + HEADER_SIZE(server) - 1,
+				       pdu_length - HEADER_SIZE(server) + 1
+				       + server->vals->header_preamble_size);
+
 	if (length < 0)
 		return length;
 	server->total_read += length;
@@ -862,20 +866,26 @@  cifs_demultiplex_thread(void *p)
 		length = cifs_read_from_socket(server, buf, pdu_length);
 		if (length < 0)
 			continue;
-		server->total_read = length;
+
+		if (server->vals->header_preamble_size == 0)
+			server->total_read = 0;
+		else
+			server->total_read = length;
 
 		/*
 		 * The right amount was read from socket - 4 bytes,
 		 * so we can now interpret the length field.
 		 */
 		pdu_length = get_rfc1002_length(buf);
+		server->total_size = pdu_length;
 
 		cifs_dbg(FYI, "RFC1002 header 0x%x\n", pdu_length);
 		if (!is_smb_response(server, buf[0]))
 			continue;
 
 		/* make sure we have enough to get to the MID */
-		if (pdu_length < HEADER_SIZE(server) - 1 - 4) {
+		if (pdu_length < HEADER_SIZE(server) - 1 -
+		    server->vals->header_preamble_size) {
 			cifs_dbg(VFS, "SMB response too short (%u bytes)\n",
 				 pdu_length);
 			cifs_reconnect(server);
@@ -884,18 +894,20 @@  cifs_demultiplex_thread(void *p)
 		}
 
 		/* read down to the MID */
-		length = cifs_read_from_socket(server, buf + 4,
-					       HEADER_SIZE(server) - 1 - 4);
+		length = cifs_read_from_socket(server,
+			     buf + server->vals->header_preamble_size,
+			     HEADER_SIZE(server) - 1
+			     - server->vals->header_preamble_size);
 		if (length < 0)
 			continue;
 		server->total_read += length;
 
 		if (server->ops->is_transform_hdr &&
 		    server->ops->receive_transform &&
-		    server->ops->is_transform_hdr(buf)) {
+		    server->ops->is_transform_hdr(buf))
 			length = server->ops->receive_transform(server,
 								&mid_entry);
-		} else {
+		else {
 			mid_entry = server->ops->find_mid(server, buf);
 
 			if (!mid_entry || !mid_entry->receive)
diff --git a/fs/cifs/misc.c b/fs/cifs/misc.c
index eea93ac15ef0..37022a34982b 100644
--- a/fs/cifs/misc.c
+++ b/fs/cifs/misc.c
@@ -151,7 +151,7 @@  cifs_buf_get(void)
 	 * SMB2 header is bigger than CIFS one - no problems to clean some
 	 * more bytes for CIFS.
 	 */
-	size_t buf_size = sizeof(struct smb2_hdr);
+	size_t buf_size = sizeof(struct smb2_sync_hdr);
 
 	/*
 	 * We could use negotiated size instead of max_msgsize -
diff --git a/fs/cifs/smb1ops.c b/fs/cifs/smb1ops.c
index a723df3e0197..4c87265050fc 100644
--- a/fs/cifs/smb1ops.c
+++ b/fs/cifs/smb1ops.c
@@ -1120,6 +1120,7 @@  struct smb_version_values smb1_values = {
 	.exclusive_lock_type = 0,
 	.shared_lock_type = LOCKING_ANDX_SHARED_LOCK,
 	.unlock_lock_type = 0,
+	.header_preamble_size = 4,
 	.header_size = sizeof(struct smb_hdr),
 	.max_header_size = MAX_CIFS_HDR_SIZE,
 	.read_rsp_size = sizeof(READ_RSP),
diff --git a/fs/cifs/smb2glob.h b/fs/cifs/smb2glob.h
index 401a5d856636..0ffa18094335 100644
--- a/fs/cifs/smb2glob.h
+++ b/fs/cifs/smb2glob.h
@@ -61,9 +61,4 @@ 
 /* Maximum buffer size value we can send with 1 credit */
 #define SMB2_MAX_BUFFER_SIZE 65536
 
-static inline struct smb2_sync_hdr *get_sync_hdr(void *buf)
-{
-	return &(((struct smb2_hdr *)buf)->sync_hdr);
-}
-
 #endif	/* _SMB2_GLOB_H */
diff --git a/fs/cifs/smb2maperror.c b/fs/cifs/smb2maperror.c
index 62c88dfed57b..8484058346cd 100644
--- a/fs/cifs/smb2maperror.c
+++ b/fs/cifs/smb2maperror.c
@@ -2450,10 +2450,14 @@  smb2_print_status(__le32 status)
 int
 map_smb2_to_linux_error(char *buf, bool log_err)
 {
-	struct smb2_sync_hdr *shdr = get_sync_hdr(buf);
+	struct smb2_sync_hdr *shdr;
 	unsigned int i;
 	int rc = -EIO;
-	__le32 smb2err = shdr->Status;
+	__le32 smb2err;
+
+	shdr = (struct smb2_sync_hdr *)buf;
+
+	smb2err = shdr->Status;
 
 	if (smb2err == 0)
 		return 0;
diff --git a/fs/cifs/smb2misc.c b/fs/cifs/smb2misc.c
index 76d03abaa38c..3bed50ba0d2f 100644
--- a/fs/cifs/smb2misc.c
+++ b/fs/cifs/smb2misc.c
@@ -96,23 +96,23 @@  static const __le16 smb2_rsp_struct_sizes[NUMBER_OF_SMB2_COMMANDS] = {
 int
 smb2_check_message(char *buf, unsigned int length, struct TCP_Server_Info *srvr)
 {
-	struct smb2_pdu *pdu = (struct smb2_pdu *)buf;
-	struct smb2_hdr *hdr = &pdu->hdr;
-	struct smb2_sync_hdr *shdr = get_sync_hdr(buf);
+	struct smb2_sync_pdu *pdu;
+	struct smb2_sync_hdr *shdr;
 	__u64 mid;
-	__u32 len = get_rfc1002_length(buf);
 	__u32 clc_len;  /* calculated length */
 	int command;
+	int pdu_size;
+	int hdr_size;
 
-	/* BB disable following printk later */
-	cifs_dbg(FYI, "%s length: 0x%x, smb_buf_length: 0x%x\n",
-		 __func__, length, len);
+	shdr = (struct smb2_sync_hdr *)buf;
+	pdu_size = sizeof(struct smb2_sync_pdu);
+	hdr_size = sizeof(struct smb2_sync_hdr);
+	pdu = (struct smb2_sync_pdu *)shdr;
 
 	/*
 	 * Add function to do table lookup of StructureSize by command
 	 * ie Validate the wct via smb2_struct_sizes table above
 	 */
-
 	if (shdr->ProtocolId == SMB2_TRANSFORM_PROTO_NUM) {
 		struct smb2_transform_hdr *thdr =
 			(struct smb2_transform_hdr *)buf;
@@ -136,8 +136,8 @@  smb2_check_message(char *buf, unsigned int length, struct TCP_Server_Info *srvr)
 	}
 
 	mid = le64_to_cpu(shdr->MessageId);
-	if (length < sizeof(struct smb2_pdu)) {
-		if ((length >= sizeof(struct smb2_hdr))
+	if (length < pdu_size) {
+		if ((length >= hdr_size)
 		    && (shdr->Status != 0)) {
 			pdu->StructureSize2 = 0;
 			/*
@@ -150,7 +150,7 @@  smb2_check_message(char *buf, unsigned int length, struct TCP_Server_Info *srvr)
 		}
 		return 1;
 	}
-	if (len > CIFSMaxBufSize + MAX_SMB2_HDR_SIZE - 4) {
+	if (length > CIFSMaxBufSize + MAX_SMB2_HDR_SIZE) {
 		cifs_dbg(VFS, "SMB length greater than maximum, mid=%llu\n",
 			 mid);
 		return 1;
@@ -189,26 +189,20 @@  smb2_check_message(char *buf, unsigned int length, struct TCP_Server_Info *srvr)
 		}
 	}
 
-	if (4 + len != length) {
-		cifs_dbg(VFS, "Total length %u RFC1002 length %u mismatch mid %llu\n",
-			 length, 4 + len, mid);
-		return 1;
-	}
+	clc_len = smb2_calc_size(buf);
 
-	clc_len = smb2_calc_size(hdr);
-
-	if (4 + len != clc_len) {
+	if (length != clc_len) {
 		cifs_dbg(FYI, "Calculated size %u length %u mismatch mid %llu\n",
-			 clc_len, 4 + len, mid);
+			 clc_len, length, mid);
 		/* create failed on symlink */
 		if (command == SMB2_CREATE_HE &&
 		    shdr->Status == STATUS_STOPPED_ON_SYMLINK)
 			return 0;
 		/* Windows 7 server returns 24 bytes more */
-		if (clc_len + 20 == len && command == SMB2_OPLOCK_BREAK_HE)
+		if (clc_len + 24 == length && command == SMB2_OPLOCK_BREAK_HE)
 			return 0;
 		/* server can return one byte more due to implied bcc[0] */
-		if (clc_len == 4 + len + 1)
+		if (clc_len == length + 1)
 			return 0;
 
 		/*
@@ -218,10 +212,10 @@  smb2_check_message(char *buf, unsigned int length, struct TCP_Server_Info *srvr)
 		 * Log the server error (once), but allow it and continue
 		 * since the frame is parseable.
 		 */
-		if (clc_len < 4 /* RFC1001 header size */ + len) {
+		if (clc_len < length) {
 			printk_once(KERN_WARNING
 				"SMB2 server sent bad RFC1001 len %d not %d\n",
-				len, clc_len - 4);
+				length, clc_len);
 			return 0;
 		}
 
@@ -262,15 +256,14 @@  static const bool has_smb2_data_area[NUMBER_OF_SMB2_COMMANDS] = {
  * area and the offset to it (from the beginning of the smb are also returned.
  */
 char *
-smb2_get_data_area_len(int *off, int *len, struct smb2_hdr *hdr)
+smb2_get_data_area_len(int *off, int *len, struct smb2_sync_hdr *shdr)
 {
-	struct smb2_sync_hdr *shdr = get_sync_hdr(hdr);
 	*off = 0;
 	*len = 0;
 
 	/* error responses do not have data area */
 	if (shdr->Status && shdr->Status != STATUS_MORE_PROCESSING_REQUIRED &&
-	    (((struct smb2_err_rsp *)hdr)->StructureSize) ==
+	    (((struct smb2_err_rsp *)shdr)->StructureSize) ==
 						SMB2_ERROR_STRUCTURE_SIZE2)
 		return NULL;
 
@@ -282,42 +275,44 @@  smb2_get_data_area_len(int *off, int *len, struct smb2_hdr *hdr)
 	switch (shdr->Command) {
 	case SMB2_NEGOTIATE:
 		*off = le16_to_cpu(
-		    ((struct smb2_negotiate_rsp *)hdr)->SecurityBufferOffset);
+		    ((struct smb2_negotiate_rsp *)shdr)->SecurityBufferOffset);
 		*len = le16_to_cpu(
-		    ((struct smb2_negotiate_rsp *)hdr)->SecurityBufferLength);
+		    ((struct smb2_negotiate_rsp *)shdr)->SecurityBufferLength);
 		break;
 	case SMB2_SESSION_SETUP:
 		*off = le16_to_cpu(
-		    ((struct smb2_sess_setup_rsp *)hdr)->SecurityBufferOffset);
+		  ((struct smb2_sess_setup_rsp *)shdr)->SecurityBufferOffset);
 		*len = le16_to_cpu(
-		    ((struct smb2_sess_setup_rsp *)hdr)->SecurityBufferLength);
+		  ((struct smb2_sess_setup_rsp *)shdr)->SecurityBufferLength);
 		break;
 	case SMB2_CREATE:
 		*off = le32_to_cpu(
-		    ((struct smb2_create_rsp *)hdr)->CreateContextsOffset);
+		    ((struct smb2_create_rsp *)shdr)->CreateContextsOffset);
 		*len = le32_to_cpu(
-		    ((struct smb2_create_rsp *)hdr)->CreateContextsLength);
+		    ((struct smb2_create_rsp *)shdr)->CreateContextsLength);
 		break;
 	case SMB2_QUERY_INFO:
 		*off = le16_to_cpu(
-		    ((struct smb2_query_info_rsp *)hdr)->OutputBufferOffset);
+		    ((struct smb2_query_info_rsp *)shdr)->OutputBufferOffset);
 		*len = le32_to_cpu(
-		    ((struct smb2_query_info_rsp *)hdr)->OutputBufferLength);
+		    ((struct smb2_query_info_rsp *)shdr)->OutputBufferLength);
 		break;
 	case SMB2_READ:
-		*off = ((struct smb2_read_rsp *)hdr)->DataOffset;
-		*len = le32_to_cpu(((struct smb2_read_rsp *)hdr)->DataLength);
+		/* TODO: is this a bug ? */
+		*off = ((struct smb2_read_rsp *)shdr)->DataOffset;
+		*len = le32_to_cpu(((struct smb2_read_rsp *)shdr)->DataLength);
 		break;
 	case SMB2_QUERY_DIRECTORY:
 		*off = le16_to_cpu(
-		  ((struct smb2_query_directory_rsp *)hdr)->OutputBufferOffset);
+		  ((struct smb2_query_directory_rsp *)shdr)->OutputBufferOffset);
 		*len = le32_to_cpu(
-		  ((struct smb2_query_directory_rsp *)hdr)->OutputBufferLength);
+		  ((struct smb2_query_directory_rsp *)shdr)->OutputBufferLength);
 		break;
 	case SMB2_IOCTL:
 		*off = le32_to_cpu(
-		  ((struct smb2_ioctl_rsp *)hdr)->OutputOffset);
-		*len = le32_to_cpu(((struct smb2_ioctl_rsp *)hdr)->OutputCount);
+		  ((struct smb2_ioctl_rsp *)shdr)->OutputOffset);
+		*len = le32_to_cpu(
+		  ((struct smb2_ioctl_rsp *)shdr)->OutputCount);
 		break;
 	case SMB2_CHANGE_NOTIFY:
 	default:
@@ -362,13 +357,16 @@  smb2_get_data_area_len(int *off, int *len, struct smb2_hdr *hdr)
 unsigned int
 smb2_calc_size(void *buf)
 {
-	struct smb2_pdu *pdu = (struct smb2_pdu *)buf;
-	struct smb2_hdr *hdr = &pdu->hdr;
-	struct smb2_sync_hdr *shdr = get_sync_hdr(hdr);
+	struct smb2_sync_pdu *pdu;
+	struct smb2_sync_hdr *shdr;
 	int offset; /* the offset from the beginning of SMB to data area */
 	int data_length; /* the length of the variable length data area */
 	/* Structure Size has already been checked to make sure it is 64 */
-	int len = 4 + le16_to_cpu(shdr->StructureSize);
+	int len;
+
+	pdu = (struct smb2_sync_pdu *)buf;
+	shdr = &pdu->sync_hdr;
+	len = le16_to_cpu(shdr->StructureSize);
 
 	/*
 	 * StructureSize2, ie length of fixed parameter area has already
@@ -379,7 +377,7 @@  smb2_calc_size(void *buf)
 	if (has_smb2_data_area[le16_to_cpu(shdr->Command)] == false)
 		goto calc_size_exit;
 
-	smb2_get_data_area_len(&offset, &data_length, hdr);
+	smb2_get_data_area_len(&offset, &data_length, shdr);
 	cifs_dbg(FYI, "SMB2 data length %d offset %d\n", data_length, offset);
 
 	if (data_length > 0) {
@@ -387,15 +385,14 @@  smb2_calc_size(void *buf)
 		 * Check to make sure that data area begins after fixed area,
 		 * Note that last byte of the fixed area is part of data area
 		 * for some commands, typically those with odd StructureSize,
-		 * so we must add one to the calculation (and 4 to account for
-		 * the size of the RFC1001 hdr.
+		 * so we must add one to the calculation.
 		 */
-		if (offset + 4 + 1 < len) {
+		if (offset + 1 < len) {
 			cifs_dbg(VFS, "data area offset %d overlaps SMB2 header %d\n",
-				 offset + 4 + 1, len);
+				 offset + 1, len);
 			data_length = 0;
 		} else {
-			len = 4 + offset + data_length;
+			len = offset + data_length;
 		}
 	}
 calc_size_exit:
@@ -578,7 +575,7 @@  smb2_is_valid_lease_break(char *buffer)
 bool
 smb2_is_valid_oplock_break(char *buffer, struct TCP_Server_Info *server)
 {
-	struct smb2_oplock_break_rsp *rsp = (struct smb2_oplock_break_rsp *)buffer;
+	struct smb2_oplock_break *rsp = (struct smb2_oplock_break *)buffer;
 	struct list_head *tmp, *tmp1, *tmp2;
 	struct cifs_ses *ses;
 	struct cifs_tcon *tcon;
@@ -587,7 +584,7 @@  smb2_is_valid_oplock_break(char *buffer, struct TCP_Server_Info *server)
 
 	cifs_dbg(FYI, "Checking for oplock break\n");
 
-	if (rsp->hdr.sync_hdr.Command != SMB2_OPLOCK_BREAK)
+	if (rsp->sync_hdr.Command != SMB2_OPLOCK_BREAK)
 		return false;
 
 	if (rsp->StructureSize !=
@@ -678,11 +675,15 @@  smb2_cancelled_close_fid(struct work_struct *work)
 int
 smb2_handle_cancelled_mid(char *buffer, struct TCP_Server_Info *server)
 {
-	struct smb2_sync_hdr *sync_hdr = get_sync_hdr(buffer);
-	struct smb2_create_rsp *rsp = (struct smb2_create_rsp *)buffer;
+	struct smb2_sync_hdr *sync_hdr;
+	struct smb2_create_rsp *rsp;
 	struct cifs_tcon *tcon;
 	struct close_cancelled_open *cancelled;
 
+	sync_hdr = (struct smb2_sync_hdr *)buffer;
+
+	rsp = (struct smb2_create_rsp *)sync_hdr;
+
 	if (sync_hdr->Command != SMB2_CREATE ||
 	    sync_hdr->Status != STATUS_SUCCESS)
 		return 0;
diff --git a/fs/cifs/smb2ops.c b/fs/cifs/smb2ops.c
index ed88ab8a4774..fef40876a77a 100644
--- a/fs/cifs/smb2ops.c
+++ b/fs/cifs/smb2ops.c
@@ -122,7 +122,14 @@  smb2_get_credits_field(struct TCP_Server_Info *server, const int optype)
 static unsigned int
 smb2_get_credits(struct mid_q_entry *mid)
 {
-	struct smb2_sync_hdr *shdr = get_sync_hdr(mid->resp_buf);
+	char *buf = mid->resp_buf;
+	struct smb2_sync_hdr *shdr;
+
+	if ( *(__u32 *)buf == SMB2_PROTO_NUMBER ||
+	     *(__u32 *)buf == SMB2_TRANSFORM_PROTO_NUM)
+		shdr = (struct smb2_sync_hdr *)buf;
+	else
+		shdr = (struct smb2_sync_hdr *)(buf + 4);
 
 	return le16_to_cpu(shdr->CreditRequest);
 }
@@ -189,8 +196,12 @@  static struct mid_q_entry *
 smb2_find_mid(struct TCP_Server_Info *server, char *buf)
 {
 	struct mid_q_entry *mid;
-	struct smb2_sync_hdr *shdr = get_sync_hdr(buf);
-	__u64 wire_mid = le64_to_cpu(shdr->MessageId);
+	struct smb2_sync_hdr *shdr;
+	__u64 wire_mid;
+
+	shdr = (struct smb2_sync_hdr *)buf;
+
+	wire_mid = le64_to_cpu(shdr->MessageId);
 
 	if (shdr->ProtocolId == SMB2_TRANSFORM_PROTO_NUM) {
 		cifs_dbg(VFS, "encrypted frame parsing not supported yet");
@@ -214,7 +225,9 @@  static void
 smb2_dump_detail(void *buf)
 {
 #ifdef CONFIG_CIFS_DEBUG2
-	struct smb2_sync_hdr *shdr = get_sync_hdr(buf);
+	struct smb2_sync_hdr *shdr;
+	
+	shdr = (struct smb2_sync_hdr *)buf;
 
 	cifs_dbg(VFS, "Cmd: %d Err: 0x%x Flags: 0x%x Mid: %llu Pid: %d\n",
 		 shdr->Command, shdr->Status, shdr->Flags, shdr->MessageId,
@@ -1230,7 +1243,9 @@  smb2_close_dir(const unsigned int xid, struct cifs_tcon *tcon,
 static bool
 smb2_is_status_pending(char *buf, struct TCP_Server_Info *server, int length)
 {
-	struct smb2_sync_hdr *shdr = get_sync_hdr(buf);
+	struct smb2_sync_hdr *shdr;
+
+	shdr = (struct smb2_sync_hdr *)buf;
 
 	if (shdr->Status != STATUS_PENDING)
 		return false;
@@ -1248,7 +1263,9 @@  smb2_is_status_pending(char *buf, struct TCP_Server_Info *server, int length)
 static bool
 smb2_is_session_expired(char *buf)
 {
-	struct smb2_sync_hdr *shdr = get_sync_hdr(buf);
+	struct smb2_sync_hdr *shdr;
+
+	shdr = (struct smb2_sync_hdr *)buf;
 
 	if (shdr->Status != STATUS_NETWORK_SESSION_EXPIRED)
 		return false;
@@ -1444,6 +1461,7 @@  smb2_query_symlink(const unsigned int xid, struct cifs_tcon *tcon,
 	__u8 oplock = SMB2_OPLOCK_LEVEL_NONE;
 	struct cifs_open_parms oparms;
 	struct cifs_fid fid;
+	struct kvec err_iov = {NULL, 0};
 	struct smb2_err_rsp *err_buf = NULL;
 	struct smb2_symlink_err_rsp *symlink;
 	unsigned int sub_len;
@@ -1464,15 +1482,16 @@  smb2_query_symlink(const unsigned int xid, struct cifs_tcon *tcon,
 	oparms.fid = &fid;
 	oparms.reconnect = false;
 
-	rc = SMB2_open(xid, &oparms, utf16_path, &oplock, NULL, &err_buf);
+	rc = SMB2_open(xid, &oparms, utf16_path, &oplock, NULL, &err_iov);
 
 	if (!rc || !err_buf) {
 		kfree(utf16_path);
 		return -ENOENT;
 	}
 
+	err_buf = err_iov.iov_base;
 	if (le32_to_cpu(err_buf->ByteCount) < sizeof(struct smb2_symlink_err_rsp) ||
-	    get_rfc1002_length(err_buf) + 4 < SMB2_SYMLINK_STRUCT_SIZE) {
+	    err_iov.iov_len < SMB2_SYMLINK_STRUCT_SIZE) {
 		kfree(utf16_path);
 		return -ENOENT;
 	}
@@ -1485,13 +1504,13 @@  smb2_query_symlink(const unsigned int xid, struct cifs_tcon *tcon,
 	print_len = le16_to_cpu(symlink->PrintNameLength);
 	print_offset = le16_to_cpu(symlink->PrintNameOffset);
 
-	if (get_rfc1002_length(err_buf) + 4 <
+	if (err_iov.iov_len <
 			SMB2_SYMLINK_STRUCT_SIZE + sub_offset + sub_len) {
 		kfree(utf16_path);
 		return -ENOENT;
 	}
 
-	if (get_rfc1002_length(err_buf) + 4 <
+	if (err_iov.iov_len <
 			SMB2_SYMLINK_STRUCT_SIZE + print_offset + print_len) {
 		kfree(utf16_path);
 		return -ENOENT;
@@ -2045,11 +2064,11 @@  smb2_dir_needs_close(struct cifsFileInfo *cfile)
 }
 
 static void
-fill_transform_hdr(struct smb2_transform_hdr *tr_hdr, struct smb_rqst *old_rq)
+fill_transform_hdr(struct smb2_transform_hdr *tr_hdr, unsigned int orig_len,
+		   struct smb_rqst *old_rq)
 {
 	struct smb2_sync_hdr *shdr =
 			(struct smb2_sync_hdr *)old_rq->rq_iov[1].iov_base;
-	unsigned int orig_len = get_rfc1002_length(old_rq->rq_iov[0].iov_base);
 
 	memset(tr_hdr, 0, sizeof(struct smb2_transform_hdr));
 	tr_hdr->ProtocolId = SMB2_TRANSFORM_PROTO_NUM;
@@ -2057,15 +2076,18 @@  fill_transform_hdr(struct smb2_transform_hdr *tr_hdr, struct smb_rqst *old_rq)
 	tr_hdr->Flags = cpu_to_le16(0x01);
 	get_random_bytes(&tr_hdr->Nonce, SMB3_AES128CMM_NONCE);
 	memcpy(&tr_hdr->SessionId, &shdr->SessionId, 8);
-	inc_rfc1001_len(tr_hdr, sizeof(struct smb2_transform_hdr) - 4);
-	inc_rfc1001_len(tr_hdr, orig_len);
 }
 
+/* Assumes:
+ * rqst->rq_iov[0]  is rfc1002 length
+ * rqst->rq_iov[1]  is tranform header
+ * rqst->rq_iov[2+] data to be encrypted/decrypted
+ */
 static struct scatterlist *
 init_sg(struct smb_rqst *rqst, u8 *sign)
 {
-	unsigned int sg_len = rqst->rq_nvec + rqst->rq_npages + 1;
-	unsigned int assoc_data_len = sizeof(struct smb2_transform_hdr) - 24;
+	unsigned int sg_len = rqst->rq_nvec + rqst->rq_npages;
+	unsigned int assoc_data_len = sizeof(struct smb2_transform_hdr) - 20;
 	struct scatterlist *sg;
 	unsigned int i;
 	unsigned int j;
@@ -2075,10 +2097,10 @@  init_sg(struct smb_rqst *rqst, u8 *sign)
 		return NULL;
 
 	sg_init_table(sg, sg_len);
-	sg_set_buf(&sg[0], rqst->rq_iov[0].iov_base + 24, assoc_data_len);
-	for (i = 1; i < rqst->rq_nvec; i++)
-		sg_set_buf(&sg[i], rqst->rq_iov[i].iov_base,
-						rqst->rq_iov[i].iov_len);
+	sg_set_buf(&sg[0], rqst->rq_iov[1].iov_base + 20, assoc_data_len);
+	for (i = 1; i < rqst->rq_nvec - 1; i++)
+		sg_set_buf(&sg[i], rqst->rq_iov[i+1].iov_base,
+						rqst->rq_iov[i+1].iov_len);
 	for (j = 0; i < sg_len - 1; i++, j++) {
 		unsigned int len = (j < rqst->rq_npages - 1) ? rqst->rq_pagesz
 							: rqst->rq_tailsz;
@@ -2110,17 +2132,18 @@  smb2_get_enc_key(struct TCP_Server_Info *server, __u64 ses_id, int enc, u8 *key)
 }
 /*
  * Encrypt or decrypt @rqst message. @rqst has the following format:
- * iov[0] - transform header (associate data),
- * iov[1-N] and pages - data to encrypt.
- * On success return encrypted data in iov[1-N] and pages, leave iov[0]
+ * iov[0] - rfc1002 length
+ * iov[1] - transform header (associate data),
+ * iov[2-N] and pages - data to encrypt.
+ * On success return encrypted data in iov[2-N] and pages, leave iov[0-1]
  * untouched.
  */
 static int
 crypt_message(struct TCP_Server_Info *server, struct smb_rqst *rqst, int enc)
 {
 	struct smb2_transform_hdr *tr_hdr =
-			(struct smb2_transform_hdr *)rqst->rq_iov[0].iov_base;
-	unsigned int assoc_data_len = sizeof(struct smb2_transform_hdr) - 24;
+			(struct smb2_transform_hdr *)rqst->rq_iov[1].iov_base;
+	unsigned int assoc_data_len = sizeof(struct smb2_transform_hdr) - 20;
 	int rc = 0;
 	struct scatterlist *sg;
 	u8 sign[SMB2_SIGNATURE_SIZE] = {};
@@ -2132,6 +2155,7 @@  crypt_message(struct TCP_Server_Info *server, struct smb_rqst *rqst, int enc)
 	struct crypto_aead *tfm;
 	unsigned int crypt_len = le32_to_cpu(tr_hdr->OriginalMessageSize);
 
+	/* Fixme compounding: get rid of iov[0] */
 	rc = smb2_get_enc_key(server, tr_hdr->SessionId, enc, key);
 	if (rc) {
 		cifs_dbg(VFS, "%s: Could not get %scryption key\n", __func__,
@@ -2207,6 +2231,9 @@  crypt_message(struct TCP_Server_Info *server, struct smb_rqst *rqst, int enc)
 	return rc;
 }
 
+/* This is called from smb_send_rqst. At this point we have the rfc1002
+ * header as the first element in the vector.
+ */
 static int
 smb3_init_transform_rq(struct TCP_Server_Info *server, struct smb_rqst *new_rq,
 		       struct smb_rqst *old_rq)
@@ -2215,6 +2242,7 @@  smb3_init_transform_rq(struct TCP_Server_Info *server, struct smb_rqst *new_rq,
 	struct page **pages;
 	struct smb2_transform_hdr *tr_hdr;
 	unsigned int npages = old_rq->rq_npages;
+	unsigned int orig_len = get_rfc1002_length(old_rq->rq_iov[0].iov_base);
 	int i;
 	int rc = -ENOMEM;
 
@@ -2233,24 +2261,34 @@  smb3_init_transform_rq(struct TCP_Server_Info *server, struct smb_rqst *new_rq,
 			goto err_free_pages;
 	}
 
-	iov = kmalloc_array(old_rq->rq_nvec, sizeof(struct kvec), GFP_KERNEL);
+	/* Make space for one extra iov to hold the transform header */
+	iov = kmalloc_array(old_rq->rq_nvec + 1, sizeof(struct kvec),
+			    GFP_KERNEL);
 	if (!iov)
 		goto err_free_pages;
 
 	/* copy all iovs from the old except the 1st one (rfc1002 length) */
-	memcpy(&iov[1], &old_rq->rq_iov[1],
+	memcpy(&iov[2], &old_rq->rq_iov[1],
 				sizeof(struct kvec) * (old_rq->rq_nvec - 1));
+	/* copy the rfc1002 iov */
+	iov[0].iov_base = old_rq->rq_iov[0].iov_base;
+	iov[0].iov_len  = old_rq->rq_iov[0].iov_len;
+
 	new_rq->rq_iov = iov;
-	new_rq->rq_nvec = old_rq->rq_nvec;
+	new_rq->rq_nvec = old_rq->rq_nvec + 1;
 
 	tr_hdr = kmalloc(sizeof(struct smb2_transform_hdr), GFP_KERNEL);
 	if (!tr_hdr)
 		goto err_free_iov;
 
-	/* fill the 1st iov with a transform header */
-	fill_transform_hdr(tr_hdr, old_rq);
-	new_rq->rq_iov[0].iov_base = tr_hdr;
-	new_rq->rq_iov[0].iov_len = sizeof(struct smb2_transform_hdr);
+	/* fill the 2nd iov with a transform header */
+	fill_transform_hdr(tr_hdr, orig_len, old_rq);
+	new_rq->rq_iov[1].iov_base = tr_hdr;
+	new_rq->rq_iov[1].iov_len = sizeof(struct smb2_transform_hdr);
+
+	/* Update rfc1002 header */
+	inc_rfc1001_len(new_rq->rq_iov[0].iov_base,
+			sizeof(struct smb2_transform_hdr));
 
 	/* copy pages form the old */
 	for (i = 0; i < npages; i++) {
@@ -2290,7 +2328,7 @@  smb3_free_transform_rq(struct smb_rqst *rqst)
 		put_page(rqst->rq_pages[i]);
 	kfree(rqst->rq_pages);
 	/* free transform header */
-	kfree(rqst->rq_iov[0].iov_base);
+	kfree(rqst->rq_iov[1].iov_base);
 	kfree(rqst->rq_iov);
 }
 
@@ -2307,18 +2345,19 @@  decrypt_raw_data(struct TCP_Server_Info *server, char *buf,
 		 unsigned int buf_data_size, struct page **pages,
 		 unsigned int npages, unsigned int page_data_size)
 {
-	struct kvec iov[2];
+	struct kvec iov[3];
 	struct smb_rqst rqst = {NULL};
-	struct smb2_hdr *hdr;
 	int rc;
 
-	iov[0].iov_base = buf;
-	iov[0].iov_len = sizeof(struct smb2_transform_hdr);
-	iov[1].iov_base = buf + sizeof(struct smb2_transform_hdr);
-	iov[1].iov_len = buf_data_size;
+	iov[0].iov_base = NULL;
+	iov[0].iov_len = 0;
+	iov[1].iov_base = buf;
+	iov[1].iov_len = sizeof(struct smb2_transform_hdr);
+	iov[2].iov_base = buf + sizeof(struct smb2_transform_hdr);
+	iov[2].iov_len = buf_data_size;
 
 	rqst.rq_iov = iov;
-	rqst.rq_nvec = 2;
+	rqst.rq_nvec = 3;
 	rqst.rq_pages = pages;
 	rqst.rq_npages = npages;
 	rqst.rq_pagesz = PAGE_SIZE;
@@ -2330,10 +2369,9 @@  decrypt_raw_data(struct TCP_Server_Info *server, char *buf,
 	if (rc)
 		return rc;
 
-	memmove(buf + 4, iov[1].iov_base, buf_data_size);
-	hdr = (struct smb2_hdr *)buf;
-	hdr->smb2_buf_length = cpu_to_be32(buf_data_size + page_data_size);
-	server->total_read = buf_data_size + page_data_size + 4;
+	memmove(buf, iov[2].iov_base, buf_data_size);
+
+	server->total_read = buf_data_size + page_data_size;
 
 	return rc;
 }
@@ -2406,12 +2444,14 @@  handle_read_data(struct TCP_Server_Info *server, struct mid_q_entry *mid,
 	unsigned int cur_page_idx;
 	unsigned int pad_len;
 	struct cifs_readdata *rdata = mid->callback_data;
-	struct smb2_sync_hdr *shdr = get_sync_hdr(buf);
+	struct smb2_sync_hdr *shdr;
 	struct bio_vec *bvec = NULL;
 	struct iov_iter iter;
 	struct kvec iov;
 	int length;
 
+	shdr = (struct smb2_sync_hdr *)buf;
+
 	if (shdr->Command != SMB2_READ) {
 		cifs_dbg(VFS, "only big read responses are supported\n");
 		return -ENOTSUPP;
@@ -2529,11 +2569,11 @@  receive_encrypted_read(struct TCP_Server_Info *server, struct mid_q_entry **mid)
 	unsigned int npages;
 	struct page **pages;
 	unsigned int len;
-	unsigned int buflen = get_rfc1002_length(buf) + 4;
+	unsigned int buflen = server->total_size;
 	int rc;
 	int i = 0;
 
-	len = min_t(unsigned int, buflen, server->vals->read_rsp_size - 4 +
+	len = min_t(unsigned int, buflen, server->vals->read_rsp_size +
 		sizeof(struct smb2_transform_hdr)) - HEADER_SIZE(server) + 1;
 
 	rc = cifs_read_from_socket(server, buf + HEADER_SIZE(server) - 1, len);
@@ -2541,7 +2581,7 @@  receive_encrypted_read(struct TCP_Server_Info *server, struct mid_q_entry **mid)
 		return rc;
 	server->total_read += rc;
 
-	len = le32_to_cpu(tr_hdr->OriginalMessageSize) + 4 -
+	len = le32_to_cpu(tr_hdr->OriginalMessageSize) -
 						server->vals->read_rsp_size;
 	npages = DIV_ROUND_UP(len, PAGE_SIZE);
 
@@ -2568,7 +2608,7 @@  receive_encrypted_read(struct TCP_Server_Info *server, struct mid_q_entry **mid)
 	if (rc)
 		goto free_pages;
 
-	rc = decrypt_raw_data(server, buf, server->vals->read_rsp_size - 4,
+	rc = decrypt_raw_data(server, buf, server->vals->read_rsp_size,
 			      pages, npages, len);
 	if (rc)
 		goto free_pages;
@@ -2600,12 +2640,12 @@  receive_encrypted_standard(struct TCP_Server_Info *server,
 {
 	int length;
 	char *buf = server->smallbuf;
-	unsigned int pdu_length = get_rfc1002_length(buf);
+	unsigned int pdu_length = server->total_size;
 	unsigned int buf_size;
 	struct mid_q_entry *mid_entry;
 
 	/* switch to large buffer if too big for a small one */
-	if (pdu_length + 4 > MAX_CIFS_SMALL_BUFFER_SIZE) {
+	if (pdu_length > MAX_CIFS_SMALL_BUFFER_SIZE) {
 		server->large_buf = true;
 		memcpy(server->bigbuf, buf, server->total_read);
 		buf = server->bigbuf;
@@ -2613,12 +2653,12 @@  receive_encrypted_standard(struct TCP_Server_Info *server,
 
 	/* now read the rest */
 	length = cifs_read_from_socket(server, buf + HEADER_SIZE(server) - 1,
-				pdu_length - HEADER_SIZE(server) + 1 + 4);
+				pdu_length - HEADER_SIZE(server) + 1);
 	if (length < 0)
 		return length;
 	server->total_read += length;
 
-	buf_size = pdu_length + 4 - sizeof(struct smb2_transform_hdr);
+	buf_size = pdu_length - sizeof(struct smb2_transform_hdr);
 	length = decrypt_raw_data(server, buf, buf_size, NULL, 0, 0);
 	if (length)
 		return length;
@@ -2643,12 +2683,12 @@  static int
 smb3_receive_transform(struct TCP_Server_Info *server, struct mid_q_entry **mid)
 {
 	char *buf = server->smallbuf;
-	unsigned int pdu_length = get_rfc1002_length(buf);
+	unsigned int pdu_length = server->total_size;
 	struct smb2_transform_hdr *tr_hdr = (struct smb2_transform_hdr *)buf;
 	unsigned int orig_len = le32_to_cpu(tr_hdr->OriginalMessageSize);
 
-	if (pdu_length + 4 < sizeof(struct smb2_transform_hdr) +
-						sizeof(struct smb2_sync_hdr)) {
+	if (pdu_length < sizeof(struct smb2_transform_hdr) +
+	    sizeof(struct smb2_sync_hdr)) {
 		cifs_dbg(VFS, "Transform message is too small (%u)\n",
 			 pdu_length);
 		cifs_reconnect(server);
@@ -2656,14 +2696,14 @@  smb3_receive_transform(struct TCP_Server_Info *server, struct mid_q_entry **mid)
 		return -ECONNABORTED;
 	}
 
-	if (pdu_length + 4 < orig_len + sizeof(struct smb2_transform_hdr)) {
+	if (pdu_length < orig_len + sizeof(struct smb2_transform_hdr)) {
 		cifs_dbg(VFS, "Transform message is broken\n");
 		cifs_reconnect(server);
 		wake_up(&server->response_q);
 		return -ECONNABORTED;
 	}
 
-	if (pdu_length + 4 > CIFSMaxBufSize + MAX_HEADER_SIZE(server))
+	if (pdu_length > CIFSMaxBufSize + MAX_HEADER_SIZE(server))
 		return receive_encrypted_read(server, mid);
 
 	return receive_encrypted_standard(server, mid);
@@ -3078,7 +3118,8 @@  struct smb_version_values smb20_values = {
 	.exclusive_lock_type = SMB2_LOCKFLAG_EXCLUSIVE_LOCK,
 	.shared_lock_type = SMB2_LOCKFLAG_SHARED_LOCK,
 	.unlock_lock_type = SMB2_LOCKFLAG_UNLOCK,
-	.header_size = sizeof(struct smb2_hdr),
+	.header_preamble_size = 0,
+	.header_size = sizeof(struct smb2_sync_hdr),
 	.max_header_size = MAX_SMB2_HDR_SIZE,
 	.read_rsp_size = sizeof(struct smb2_read_rsp) - 1,
 	.lock_cmd = SMB2_LOCK,
@@ -3098,7 +3139,8 @@  struct smb_version_values smb21_values = {
 	.exclusive_lock_type = SMB2_LOCKFLAG_EXCLUSIVE_LOCK,
 	.shared_lock_type = SMB2_LOCKFLAG_SHARED_LOCK,
 	.unlock_lock_type = SMB2_LOCKFLAG_UNLOCK,
-	.header_size = sizeof(struct smb2_hdr),
+	.header_preamble_size = 0,
+	.header_size = sizeof(struct smb2_sync_hdr),
 	.max_header_size = MAX_SMB2_HDR_SIZE,
 	.read_rsp_size = sizeof(struct smb2_read_rsp) - 1,
 	.lock_cmd = SMB2_LOCK,
@@ -3118,7 +3160,8 @@  struct smb_version_values smb3any_values = {
 	.exclusive_lock_type = SMB2_LOCKFLAG_EXCLUSIVE_LOCK,
 	.shared_lock_type = SMB2_LOCKFLAG_SHARED_LOCK,
 	.unlock_lock_type = SMB2_LOCKFLAG_UNLOCK,
-	.header_size = sizeof(struct smb2_hdr),
+	.header_preamble_size = 0,
+	.header_size = sizeof(struct smb2_sync_hdr),
 	.max_header_size = MAX_SMB2_HDR_SIZE,
 	.read_rsp_size = sizeof(struct smb2_read_rsp) - 1,
 	.lock_cmd = SMB2_LOCK,
@@ -3138,7 +3181,8 @@  struct smb_version_values smbdefault_values = {
 	.exclusive_lock_type = SMB2_LOCKFLAG_EXCLUSIVE_LOCK,
 	.shared_lock_type = SMB2_LOCKFLAG_SHARED_LOCK,
 	.unlock_lock_type = SMB2_LOCKFLAG_UNLOCK,
-	.header_size = sizeof(struct smb2_hdr),
+	.header_preamble_size = 0,
+	.header_size = sizeof(struct smb2_sync_hdr),
 	.max_header_size = MAX_SMB2_HDR_SIZE,
 	.read_rsp_size = sizeof(struct smb2_read_rsp) - 1,
 	.lock_cmd = SMB2_LOCK,
@@ -3158,7 +3202,8 @@  struct smb_version_values smb30_values = {
 	.exclusive_lock_type = SMB2_LOCKFLAG_EXCLUSIVE_LOCK,
 	.shared_lock_type = SMB2_LOCKFLAG_SHARED_LOCK,
 	.unlock_lock_type = SMB2_LOCKFLAG_UNLOCK,
-	.header_size = sizeof(struct smb2_hdr),
+	.header_preamble_size = 0,
+	.header_size = sizeof(struct smb2_sync_hdr),
 	.max_header_size = MAX_SMB2_HDR_SIZE,
 	.read_rsp_size = sizeof(struct smb2_read_rsp) - 1,
 	.lock_cmd = SMB2_LOCK,
@@ -3178,7 +3223,8 @@  struct smb_version_values smb302_values = {
 	.exclusive_lock_type = SMB2_LOCKFLAG_EXCLUSIVE_LOCK,
 	.shared_lock_type = SMB2_LOCKFLAG_SHARED_LOCK,
 	.unlock_lock_type = SMB2_LOCKFLAG_UNLOCK,
-	.header_size = sizeof(struct smb2_hdr),
+	.header_preamble_size = 0,
+	.header_size = sizeof(struct smb2_sync_hdr),
 	.max_header_size = MAX_SMB2_HDR_SIZE,
 	.read_rsp_size = sizeof(struct smb2_read_rsp) - 1,
 	.lock_cmd = SMB2_LOCK,
@@ -3199,7 +3245,8 @@  struct smb_version_values smb311_values = {
 	.exclusive_lock_type = SMB2_LOCKFLAG_EXCLUSIVE_LOCK,
 	.shared_lock_type = SMB2_LOCKFLAG_SHARED_LOCK,
 	.unlock_lock_type = SMB2_LOCKFLAG_UNLOCK,
-	.header_size = sizeof(struct smb2_hdr),
+	.header_preamble_size = 0,
+	.header_size = sizeof(struct smb2_sync_hdr),
 	.max_header_size = MAX_SMB2_HDR_SIZE,
 	.read_rsp_size = sizeof(struct smb2_read_rsp) - 1,
 	.lock_cmd = SMB2_LOCK,
diff --git a/fs/cifs/smb2pdu.c b/fs/cifs/smb2pdu.c
index c0dc0491af93..ad178150fbf3 100644
--- a/fs/cifs/smb2pdu.c
+++ b/fs/cifs/smb2pdu.c
@@ -577,7 +577,7 @@  SMB2_negotiate(const unsigned int xid, struct cifs_ses *ses)
 	server->capabilities |= SMB2_NT_FIND | SMB2_LARGE_FILES;
 
 	security_blob = smb2_get_data_area_len(&blob_offset, &blob_length,
-					       &rsp->hdr);
+					       (struct smb2_sync_hdr *)rsp);
 	/*
 	 * See MS-SMB2 section 2.2.4: if no blob, client picks default which
 	 * for us will be
@@ -921,7 +921,7 @@  SMB2_auth_kerberos(struct SMB2_sess_data *sess_data)
 		goto out_put_spnego_key;
 
 	rsp = (struct smb2_sess_setup_rsp *)sess_data->iov[0].iov_base;
-	ses->Suid = rsp->hdr.sync_hdr.SessionId;
+	ses->Suid = rsp->sync_hdr.SessionId;
 
 	ses->session_flags = le16_to_cpu(rsp->SessionFlags);
 
@@ -997,13 +997,13 @@  SMB2_sess_auth_rawntlmssp_negotiate(struct SMB2_sess_data *sess_data)
 
 	/* If true, rc here is expected and not an error */
 	if (sess_data->buf0_type != CIFS_NO_BUFFER &&
-		rsp->hdr.sync_hdr.Status == STATUS_MORE_PROCESSING_REQUIRED)
+		rsp->sync_hdr.Status == STATUS_MORE_PROCESSING_REQUIRED)
 		rc = 0;
 
 	if (rc)
 		goto out;
 
-	if (offsetof(struct smb2_sess_setup_rsp, Buffer) - 4 !=
+	if (offsetof(struct smb2_sess_setup_rsp, Buffer) !=
 			le16_to_cpu(rsp->SecurityBufferOffset)) {
 		cifs_dbg(VFS, "Invalid security buffer offset %d\n",
 			le16_to_cpu(rsp->SecurityBufferOffset));
@@ -1018,7 +1018,7 @@  SMB2_sess_auth_rawntlmssp_negotiate(struct SMB2_sess_data *sess_data)
 	cifs_dbg(FYI, "rawntlmssp session setup challenge phase\n");
 
 
-	ses->Suid = rsp->hdr.sync_hdr.SessionId;
+	ses->Suid = rsp->sync_hdr.SessionId;
 	ses->session_flags = le16_to_cpu(rsp->SessionFlags);
 
 out:
@@ -1076,7 +1076,7 @@  SMB2_sess_auth_rawntlmssp_authenticate(struct SMB2_sess_data *sess_data)
 
 	rsp = (struct smb2_sess_setup_rsp *)sess_data->iov[0].iov_base;
 
-	ses->Suid = rsp->hdr.sync_hdr.SessionId;
+	ses->Suid = rsp->sync_hdr.SessionId;
 	ses->session_flags = le16_to_cpu(rsp->SessionFlags);
 
 	rc = SMB2_sess_establish_session(sess_data);
@@ -1298,7 +1298,7 @@  SMB2_tcon(const unsigned int xid, struct cifs_ses *ses, const char *tree,
 	}
 
 	if (tcon == NULL) {
-		ses->ipc_tid = rsp->hdr.sync_hdr.TreeId;
+		ses->ipc_tid = rsp->sync_hdr.TreeId;
 		goto tcon_exit;
 	}
 
@@ -1325,7 +1325,7 @@  SMB2_tcon(const unsigned int xid, struct cifs_ses *ses, const char *tree,
 	tcon->maximal_access = le32_to_cpu(rsp->MaximalAccess);
 	tcon->tidStatus = CifsGood;
 	tcon->need_reconnect = false;
-	tcon->tid = rsp->hdr.sync_hdr.TreeId;
+	tcon->tid = rsp->sync_hdr.TreeId;
 	strlcpy(tcon->treeName, tree, sizeof(tcon->treeName));
 
 	if ((rsp->Capabilities & SMB2_SHARE_CAP_DFS) &&
@@ -1345,7 +1345,7 @@  SMB2_tcon(const unsigned int xid, struct cifs_ses *ses, const char *tree,
 	return rc;
 
 tcon_error_exit:
-	if (rsp && rsp->hdr.sync_hdr.Status == STATUS_BAD_NETWORK_NAME) {
+	if (rsp && rsp->sync_hdr.Status == STATUS_BAD_NETWORK_NAME) {
 		cifs_dbg(VFS, "BAD_NETWORK_NAME: %s\n", tree);
 	}
 	goto tcon_exit;
@@ -1451,7 +1451,7 @@  parse_lease_state(struct TCP_Server_Info *server, struct smb2_create_rsp *rsp,
 	unsigned int remaining;
 	char *name;
 
-	data_offset = (char *)rsp + 4 + le32_to_cpu(rsp->CreateContextsOffset);
+	data_offset = (char *)rsp + le32_to_cpu(rsp->CreateContextsOffset);
 	remaining = le32_to_cpu(rsp->CreateContextsLength);
 	cc = (struct create_context *)data_offset;
 	while (remaining >= sizeof(struct create_context)) {
@@ -1679,7 +1679,7 @@  alloc_path_with_tree_prefix(__le16 **out_path, int *out_size, int *out_len,
 int
 SMB2_open(const unsigned int xid, struct cifs_open_parms *oparms, __le16 *path,
 	  __u8 *oplock, struct smb2_file_all_info *buf,
-	  struct smb2_err_rsp **err_buf)
+	  struct kvec *err_iov)
 {
 	struct smb2_create_req *req;
 	struct smb2_create_rsp *rsp;
@@ -1815,9 +1815,10 @@  SMB2_open(const unsigned int xid, struct cifs_open_parms *oparms, __le16 *path,
 
 	if (rc != 0) {
 		cifs_stats_fail_inc(tcon, SMB2_CREATE_HE);
-		if (err_buf && rsp)
-			*err_buf = kmemdup(rsp, get_rfc1002_length(rsp) + 4,
-					   GFP_KERNEL);
+		if (err_iov && rsp) {
+			*err_iov = rsp_iov;
+			rsp = NULL;
+		}
 		goto creat_exit;
 	}
 
@@ -1856,7 +1857,6 @@  SMB2_ioctl(const unsigned int xid, struct cifs_tcon *tcon, u64 persistent_fid,
 {
 	struct smb2_ioctl_req *req;
 	struct smb2_ioctl_rsp *rsp;
-	struct smb2_sync_hdr *shdr;
 	struct cifs_ses *ses;
 	struct kvec iov[2];
 	struct kvec rsp_iov;
@@ -1987,7 +1987,7 @@  SMB2_ioctl(const unsigned int xid, struct cifs_tcon *tcon, u64 persistent_fid,
 		goto ioctl_exit;
 	}
 
-	if (get_rfc1002_length(rsp) < le32_to_cpu(rsp->OutputOffset) + *plen) {
+	if (rsp_iov.iov_len < le32_to_cpu(rsp->OutputOffset) + *plen) {
 		cifs_dbg(VFS, "Malformed ioctl resp: len %d offset %d\n", *plen,
 			le32_to_cpu(rsp->OutputOffset));
 		*plen = 0;
@@ -2001,8 +2001,7 @@  SMB2_ioctl(const unsigned int xid, struct cifs_tcon *tcon, u64 persistent_fid,
 		goto ioctl_exit;
 	}
 
-	shdr = get_sync_hdr(rsp);
-	memcpy(*out_data, (char *)shdr + le32_to_cpu(rsp->OutputOffset), *plen);
+	memcpy(*out_data, (char *)rsp + le32_to_cpu(rsp->OutputOffset), *plen);
 ioctl_exit:
 	free_rsp_buf(resp_buftype, rsp);
 	return rc;
@@ -2083,13 +2082,12 @@  SMB2_close(const unsigned int xid, struct cifs_tcon *tcon,
 }
 
 static int
-validate_buf(unsigned int offset, unsigned int buffer_length,
-	     struct smb2_hdr *hdr, unsigned int min_buf_size)
-
+validate_iov(unsigned int offset, unsigned int buffer_length,
+	     struct kvec *iov, unsigned int min_buf_size)
 {
-	unsigned int smb_len = be32_to_cpu(hdr->smb2_buf_length);
-	char *end_of_smb = smb_len + 4 /* RFC1001 length field */ + (char *)hdr;
-	char *begin_of_buf = 4 /* RFC1001 len field */ + offset + (char *)hdr;
+	unsigned int smb_len = iov->iov_len;
+	char *end_of_smb = smb_len + (char *)iov->iov_base;
+	char *begin_of_buf = offset + (char *)iov->iov_base;
 	char *end_of_buf = begin_of_buf + buffer_length;
 
 
@@ -2119,18 +2117,17 @@  validate_buf(unsigned int offset, unsigned int buffer_length,
  * Caller must free buffer.
  */
 static int
-validate_and_copy_buf(unsigned int offset, unsigned int buffer_length,
-		      struct smb2_hdr *hdr, unsigned int minbufsize,
+validate_and_copy_iov(unsigned int offset, unsigned int buffer_length,
+		      struct kvec *iov, unsigned int minbufsize,
 		      char *data)
-
 {
-	char *begin_of_buf = 4 /* RFC1001 len field */ + offset + (char *)hdr;
+	char *begin_of_buf = offset + (char *)iov->iov_base;
 	int rc;
 
 	if (!data)
 		return -EINVAL;
 
-	rc = validate_buf(offset, buffer_length, hdr, minbufsize);
+	rc = validate_iov(offset, buffer_length, iov, minbufsize);
 	if (rc)
 		return rc;
 
@@ -2208,9 +2205,9 @@  query_info(const unsigned int xid, struct cifs_tcon *tcon,
 		}
 	}
 
-	rc = validate_and_copy_buf(le16_to_cpu(rsp->OutputBufferOffset),
+	rc = validate_and_copy_iov(le16_to_cpu(rsp->OutputBufferOffset),
 				   le32_to_cpu(rsp->OutputBufferLength),
-				   &rsp->hdr, min_len, *data);
+				   &rsp_iov, min_len, *data);
 
 qinf_exit:
 	free_rsp_buf(resp_buftype, rsp);
@@ -2279,7 +2276,7 @@  smb2_echo_callback(struct mid_q_entry *mid)
 	unsigned int credits_received = 1;
 
 	if (mid->mid_state == MID_RESPONSE_RECEIVED)
-		credits_received = le16_to_cpu(rsp->hdr.sync_hdr.CreditRequest);
+		credits_received = le16_to_cpu(rsp->sync_hdr.CreditRequest);
 
 	DeleteMidQEntry(mid);
 	add_credits(server, credits_received, CIFS_ECHO_OP);
@@ -2629,7 +2626,6 @@  SMB2_read(const unsigned int xid, struct cifs_io_parms *io_parms,
 	int resp_buftype, rc = -EACCES;
 	struct smb2_read_plain_req *req = NULL;
 	struct smb2_read_rsp *rsp = NULL;
-	struct smb2_sync_hdr *shdr;
 	struct kvec iov[1];
 	struct kvec rsp_iov;
 	unsigned int total_len;
@@ -2670,10 +2666,8 @@  SMB2_read(const unsigned int xid, struct cifs_io_parms *io_parms,
 		*nbytes = 0;
 	}
 
-	shdr = get_sync_hdr(rsp);
-
 	if (*buf) {
-		memcpy(*buf, (char *)shdr + rsp->DataOffset, *nbytes);
+		memcpy(*buf, (char *)rsp + rsp->DataOffset, *nbytes);
 		free_rsp_buf(resp_buftype, rsp_iov.iov_base);
 	} else if (resp_buftype != CIFS_NO_BUFFER) {
 		*buf = rsp_iov.iov_base;
@@ -2700,7 +2694,7 @@  smb2_writev_callback(struct mid_q_entry *mid)
 
 	switch (mid->mid_state) {
 	case MID_RESPONSE_RECEIVED:
-		credits_received = le16_to_cpu(rsp->hdr.sync_hdr.CreditRequest);
+		credits_received = le16_to_cpu(rsp->sync_hdr.CreditRequest);
 		wdata->result = smb2_check_receive(mid, tcon->ses->server, 0);
 		if (wdata->result != 0)
 			break;
@@ -3018,7 +3012,7 @@  SMB2_query_directory(const unsigned int xid, struct cifs_tcon *tcon,
 
 	if (rc) {
 		if (rc == -ENODATA &&
-		    rsp->hdr.sync_hdr.Status == STATUS_NO_MORE_FILES) {
+		    rsp->sync_hdr.Status == STATUS_NO_MORE_FILES) {
 			srch_inf->endOfSearch = true;
 			rc = 0;
 		}
@@ -3026,8 +3020,8 @@  SMB2_query_directory(const unsigned int xid, struct cifs_tcon *tcon,
 		goto qdir_exit;
 	}
 
-	rc = validate_buf(le16_to_cpu(rsp->OutputBufferOffset),
-			  le32_to_cpu(rsp->OutputBufferLength), &rsp->hdr,
+	rc = validate_iov(le16_to_cpu(rsp->OutputBufferOffset),
+			  le32_to_cpu(rsp->OutputBufferLength), &rsp_iov,
 			  info_buf_size);
 	if (rc)
 		goto qdir_exit;
@@ -3041,10 +3035,9 @@  SMB2_query_directory(const unsigned int xid, struct cifs_tcon *tcon,
 			cifs_buf_release(srch_inf->ntwrk_buf_start);
 	}
 	srch_inf->ntwrk_buf_start = (char *)rsp;
-	srch_inf->srch_entries_start = srch_inf->last_entry = 4 /* rfclen */ +
-		(char *)&rsp->hdr + le16_to_cpu(rsp->OutputBufferOffset);
-	/* 4 for rfc1002 length field */
-	end_of_smb = get_rfc1002_length(rsp) + 4 + (char *)&rsp->hdr;
+	srch_inf->srch_entries_start = srch_inf->last_entry =
+		(char *)rsp + le16_to_cpu(rsp->OutputBufferOffset);
+	end_of_smb = rsp_iov.iov_len + (char *)rsp;
 	srch_inf->entries_in_buffer =
 			num_entries(srch_inf->srch_entries_start, end_of_smb,
 				    &srch_inf->last_entry, info_buf_size);
@@ -3280,7 +3273,7 @@  SMB2_oplock_break(const unsigned int xid, struct cifs_tcon *tcon,
 		  __u8 oplock_level)
 {
 	int rc;
-	struct smb2_oplock_break_req *req = NULL;
+	struct smb2_oplock_break *req = NULL;
 	struct cifs_ses *ses = tcon->ses;
 	int flags = CIFS_OBREAK_OP;
 	unsigned int total_len;
@@ -3356,7 +3349,7 @@  build_qfs_info_req(struct kvec *iov, struct cifs_tcon *tcon, int level,
 	req->InputBufferOffset =
 			cpu_to_le16(sizeof(struct smb2_query_info_req) - 1);
 	req->OutputBufferLength = cpu_to_le32(
-		outbuf_len + sizeof(struct smb2_query_info_rsp) - 1 - 4);
+		outbuf_len + sizeof(struct smb2_query_info_rsp) - 1);
 
 	iov->iov_base = (char *)req;
 	iov->iov_len = total_len;
@@ -3393,10 +3386,10 @@  SMB2_QFS_info(const unsigned int xid, struct cifs_tcon *tcon,
 	}
 	rsp = (struct smb2_query_info_rsp *)rsp_iov.iov_base;
 
-	info = (struct smb2_fs_full_size_info *)(4 /* RFC1001 len */ +
-		le16_to_cpu(rsp->OutputBufferOffset) + (char *)&rsp->hdr);
-	rc = validate_buf(le16_to_cpu(rsp->OutputBufferOffset),
-			  le32_to_cpu(rsp->OutputBufferLength), &rsp->hdr,
+	info = (struct smb2_fs_full_size_info *)(
+		le16_to_cpu(rsp->OutputBufferOffset) + (char *)rsp);
+	rc = validate_iov(le16_to_cpu(rsp->OutputBufferOffset),
+			  le32_to_cpu(rsp->OutputBufferLength), &rsp_iov,
 			  sizeof(struct smb2_fs_full_size_info));
 	if (!rc)
 		copy_fs_info_to_kstatfs(info, fsdata);
@@ -3451,20 +3444,20 @@  SMB2_QFS_attr(const unsigned int xid, struct cifs_tcon *tcon,
 
 	rsp_len = le32_to_cpu(rsp->OutputBufferLength);
 	offset = le16_to_cpu(rsp->OutputBufferOffset);
-	rc = validate_buf(offset, rsp_len, &rsp->hdr, min_len);
+	rc = validate_iov(offset, rsp_len, &rsp_iov, min_len);
 	if (rc)
 		goto qfsattr_exit;
 
 	if (level == FS_ATTRIBUTE_INFORMATION)
-		memcpy(&tcon->fsAttrInfo, 4 /* RFC1001 len */ + offset
-			+ (char *)&rsp->hdr, min_t(unsigned int,
+		memcpy(&tcon->fsAttrInfo, offset
+			+ (char *)rsp, min_t(unsigned int,
 			rsp_len, max_len));
 	else if (level == FS_DEVICE_INFORMATION)
-		memcpy(&tcon->fsDevInfo, 4 /* RFC1001 len */ + offset
-			+ (char *)&rsp->hdr, sizeof(FILE_SYSTEM_DEVICE_INFO));
+		memcpy(&tcon->fsDevInfo, offset
+			+ (char *)rsp, sizeof(FILE_SYSTEM_DEVICE_INFO));
 	else if (level == FS_SECTOR_SIZE_INFORMATION) {
 		struct smb3_fs_ss_info *ss_info = (struct smb3_fs_ss_info *)
-			(4 /* RFC1001 len */ + offset + (char *)&rsp->hdr);
+			(offset + (char *)rsp);
 		tcon->ss_flags = le32_to_cpu(ss_info->Flags);
 		tcon->perf_sector_size =
 			le32_to_cpu(ss_info->PhysicalBytesPerSectorForPerf);
diff --git a/fs/cifs/smb2pdu.h b/fs/cifs/smb2pdu.h
index 19d34881815f..91fd17f5c2eb 100644
--- a/fs/cifs/smb2pdu.h
+++ b/fs/cifs/smb2pdu.h
@@ -122,25 +122,10 @@  struct smb2_sync_pdu {
 	__le16 StructureSize2; /* size of wct area (varies, request specific) */
 } __packed;
 
-struct smb2_hdr {
-	__be32 smb2_buf_length;	/* big endian on wire */
-				/* length is only two or three bytes - with */
-				/* one or two byte type preceding it that MBZ */
-	struct smb2_sync_hdr sync_hdr;
-} __packed;
-
-struct smb2_pdu {
-	struct smb2_hdr hdr;
-	__le16 StructureSize2; /* size of wct area (varies, request specific) */
-} __packed;
-
 #define SMB3_AES128CMM_NONCE 11
 #define SMB3_AES128GCM_NONCE 12
 
 struct smb2_transform_hdr {
-	__be32 smb2_buf_length;	/* big endian on wire */
-				/* length is only two or three bytes - with
-				 one or two byte type preceding it that MBZ */
 	__le32 ProtocolId;	/* 0xFD 'S' 'M' 'B' */
 	__u8   Signature[16];
 	__u8   Nonce[16];
@@ -171,7 +156,7 @@  struct smb2_transform_hdr {
 #define SMB2_ERROR_STRUCTURE_SIZE2 cpu_to_le16(9)
 
 struct smb2_err_rsp {
-	struct smb2_hdr hdr;
+	struct smb2_sync_hdr sync_hdr;
 	__le16 StructureSize;
 	__le16 Reserved; /* MBZ */
 	__le32 ByteCount;  /* even if zero, at least one byte follows */
@@ -259,7 +244,7 @@  struct smb2_encryption_neg_context {
 } __packed;
 
 struct smb2_negotiate_rsp {
-	struct smb2_hdr hdr;
+	struct smb2_sync_hdr sync_hdr;
 	__le16 StructureSize;	/* Must be 65 */
 	__le16 SecurityMode;
 	__le16 DialectRevision;
@@ -299,7 +284,7 @@  struct smb2_sess_setup_req {
 #define SMB2_SESSION_FLAG_IS_NULL	0x0002
 #define SMB2_SESSION_FLAG_ENCRYPT_DATA	0x0004
 struct smb2_sess_setup_rsp {
-	struct smb2_hdr hdr;
+	struct smb2_sync_hdr sync_hdr;
 	__le16 StructureSize; /* Must be 9 */
 	__le16 SessionFlags;
 	__le16 SecurityBufferOffset;
@@ -314,7 +299,7 @@  struct smb2_logoff_req {
 } __packed;
 
 struct smb2_logoff_rsp {
-	struct smb2_hdr hdr;
+	struct smb2_sync_hdr sync_hdr;
 	__le16 StructureSize;	/* Must be 4 */
 	__le16 Reserved;
 } __packed;
@@ -332,7 +317,7 @@  struct smb2_tree_connect_req {
 } __packed;
 
 struct smb2_tree_connect_rsp {
-	struct smb2_hdr hdr;
+	struct smb2_sync_hdr sync_hdr;
 	__le16 StructureSize;	/* Must be 16 */
 	__u8   ShareType;  /* see below */
 	__u8   Reserved;
@@ -381,7 +366,7 @@  struct smb2_tree_disconnect_req {
 } __packed;
 
 struct smb2_tree_disconnect_rsp {
-	struct smb2_hdr hdr;
+	struct smb2_sync_hdr sync_hdr;
 	__le16 StructureSize;	/* Must be 4 */
 	__le16 Reserved;
 } __packed;
@@ -516,7 +501,7 @@  struct smb2_create_req {
 } __packed;
 
 struct smb2_create_rsp {
-	struct smb2_hdr hdr;
+	struct smb2_sync_hdr sync_hdr;
 	__le16 StructureSize;	/* Must be 89 */
 	__u8   OplockLevel;
 	__u8   Reserved;
@@ -771,7 +756,7 @@  struct smb2_ioctl_req {
 } __packed;
 
 struct smb2_ioctl_rsp {
-	struct smb2_hdr hdr;
+	struct smb2_sync_hdr sync_hdr;
 	__le16 StructureSize;	/* Must be 57 */
 	__u16 Reserved;
 	__le32 CtlCode;
@@ -798,7 +783,7 @@  struct smb2_close_req {
 } __packed;
 
 struct smb2_close_rsp {
-	struct smb2_hdr hdr;
+	struct smb2_sync_hdr sync_hdr;
 	__le16 StructureSize; /* 60 */
 	__le16 Flags;
 	__le32 Reserved;
@@ -821,7 +806,7 @@  struct smb2_flush_req {
 } __packed;
 
 struct smb2_flush_rsp {
-	struct smb2_hdr hdr;
+	struct smb2_sync_hdr sync_hdr;
 	__le16 StructureSize;
 	__le16 Reserved;
 } __packed;
@@ -853,7 +838,7 @@  struct smb2_read_plain_req {
 } __packed;
 
 struct smb2_read_rsp {
-	struct smb2_hdr hdr;
+	struct smb2_sync_hdr sync_hdr;
 	__le16 StructureSize; /* Must be 17 */
 	__u8   DataOffset;
 	__u8   Reserved;
@@ -884,7 +869,7 @@  struct smb2_write_req {
 } __packed;
 
 struct smb2_write_rsp {
-	struct smb2_hdr hdr;
+	struct smb2_sync_hdr sync_hdr;
 	__le16 StructureSize; /* Must be 17 */
 	__u8   DataOffset;
 	__u8   Reserved;
@@ -918,7 +903,7 @@  struct smb2_lock_req {
 } __packed;
 
 struct smb2_lock_rsp {
-	struct smb2_hdr hdr;
+	struct smb2_sync_hdr sync_hdr;
 	__le16 StructureSize; /* Must be 4 */
 	__le16 Reserved;
 } __packed;
@@ -930,7 +915,7 @@  struct smb2_echo_req {
 } __packed;
 
 struct smb2_echo_rsp {
-	struct smb2_hdr hdr;
+	struct smb2_sync_hdr sync_hdr;
 	__le16 StructureSize;	/* Must be 4 */
 	__u16  Reserved;
 } __packed;
@@ -956,7 +941,7 @@  struct smb2_query_directory_req {
 } __packed;
 
 struct smb2_query_directory_rsp {
-	struct smb2_hdr hdr;
+	struct smb2_sync_hdr sync_hdr;
 	__le16 StructureSize; /* Must be 9 */
 	__le16 OutputBufferOffset;
 	__le32 OutputBufferLength;
@@ -1005,7 +990,7 @@  struct smb2_query_info_req {
 } __packed;
 
 struct smb2_query_info_rsp {
-	struct smb2_hdr hdr;
+	struct smb2_sync_hdr sync_hdr;
 	__le16 StructureSize; /* Must be 9 */
 	__le16 OutputBufferOffset;
 	__le32 OutputBufferLength;
@@ -1027,12 +1012,11 @@  struct smb2_set_info_req {
 } __packed;
 
 struct smb2_set_info_rsp {
-	struct smb2_hdr hdr;
+	struct smb2_sync_hdr sync_hdr;
 	__le16 StructureSize; /* Must be 2 */
 } __packed;
 
-/* oplock break without an rfc1002 header */
-struct smb2_oplock_break_req {
+struct smb2_oplock_break {
 	struct smb2_sync_hdr sync_hdr;
 	__le16 StructureSize; /* Must be 24 */
 	__u8   OplockLevel;
@@ -1042,21 +1026,10 @@  struct smb2_oplock_break_req {
 	__u64  VolatileFid;
 } __packed;
 
-/* oplock break with an rfc1002 header */
-struct smb2_oplock_break_rsp {
-	struct smb2_hdr hdr;
-	__le16 StructureSize; /* Must be 24 */
-	__u8   OplockLevel;
-	__u8   Reserved;
-	__le32 Reserved2;
-	__u64  PersistentFid;
-	__u64  VolatileFid;
-} __packed;
-
 #define SMB2_NOTIFY_BREAK_LEASE_FLAG_ACK_REQUIRED cpu_to_le32(0x01)
 
 struct smb2_lease_break {
-	struct smb2_hdr hdr;
+	struct smb2_sync_hdr sync_hdr;
 	__le16 StructureSize; /* Must be 44 */
 	__le16 Reserved;
 	__le32 Flags;
diff --git a/fs/cifs/smb2proto.h b/fs/cifs/smb2proto.h
index e9ab5227e7a8..089a6ef936b8 100644
--- a/fs/cifs/smb2proto.h
+++ b/fs/cifs/smb2proto.h
@@ -37,7 +37,8 @@  extern int map_smb2_to_linux_error(char *buf, bool log_err);
 extern int smb2_check_message(char *buf, unsigned int length,
 			      struct TCP_Server_Info *server);
 extern unsigned int smb2_calc_size(void *buf);
-extern char *smb2_get_data_area_len(int *off, int *len, struct smb2_hdr *hdr);
+extern char *smb2_get_data_area_len(int *off, int *len,
+				    struct smb2_sync_hdr *shdr);
 extern __le16 *cifs_convert_path_to_utf16(const char *from,
 					  struct cifs_sb_info *cifs_sb);
 
@@ -122,7 +123,7 @@  extern int SMB2_tdis(const unsigned int xid, struct cifs_tcon *tcon);
 extern int SMB2_open(const unsigned int xid, struct cifs_open_parms *oparms,
 		     __le16 *path, __u8 *oplock,
 		     struct smb2_file_all_info *buf,
-		     struct smb2_err_rsp **err_buf);
+		     struct kvec *err_iov);
 extern int SMB2_ioctl(const unsigned int xid, struct cifs_tcon *tcon,
 		     u64 persistent_fid, u64 volatile_fid, u32 opcode,
 		     bool is_fsctl, bool use_ipc,
diff --git a/fs/cifs/smb2transport.c b/fs/cifs/smb2transport.c
index 99493946e2f9..cf37c6651bf6 100644
--- a/fs/cifs/smb2transport.c
+++ b/fs/cifs/smb2transport.c
@@ -624,10 +624,10 @@  smb2_check_receive(struct mid_q_entry *mid, struct TCP_Server_Info *server,
 	struct smb_rqst rqst = { .rq_iov = iov,
 				 .rq_nvec = 2 };
 
-	iov[0].iov_base = (char *)mid->resp_buf;
+	iov[0].iov_base = NULL;
 	iov[0].iov_len = 4;
-	iov[1].iov_base = (char *)mid->resp_buf + 4;
-	iov[1].iov_len = len;
+	iov[1].iov_base = (char *)mid->resp_buf;
+	iov[1].iov_len = server->total_size;
 
 	dump_smb(mid->resp_buf, min_t(u32, 80, len));
 	/* convert the length into a more usable form */
diff --git a/fs/cifs/transport.c b/fs/cifs/transport.c
index 510f41a435c8..5cecf67af8f1 100644
--- a/fs/cifs/transport.c
+++ b/fs/cifs/transport.c
@@ -779,7 +779,9 @@  cifs_send_recv(const unsigned int xid, struct cifs_ses *ses,
 
 	buf = (char *)midQ->resp_buf;
 	resp_iov->iov_base = buf;
-	resp_iov->iov_len = get_rfc1002_length(buf) + 4;
+	resp_iov->iov_len = ses->server->total_size +
+		ses->server->vals->header_preamble_size;
+
 	if (midQ->large_buf)
 		*resp_buf_type = CIFS_LARGE_BUFFER;
 	else