cifs: remove header_preamble_size where it is always 0

Since header_preamble_size is 0 for SMB2+ we can remove it in those
code paths that are only invoked from SMB2.

Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Steve French <stfrench@microsoft.com>

3 files changed, 48 insertions, 68 deletions

diff --git a/fs/cifs/smb2misc.c b/fs/cifs/smb2misc.c
index d587a090292a..ea964f759060 100644
--- a/fs/cifs/smb2misc.c
+++ b/fs/cifs/smb2misc.c
@@ -95,8 +95,7 @@ static const __le16 smb2_rsp_struct_sizes[NUMBER_OF_SMB2_COMMANDS] = {
 
 #ifdef CONFIG_CIFS_SMB311
 static __u32 get_neg_ctxt_len(struct smb2_sync_hdr *hdr, __u32 len,
-			      __u32 non_ctxlen,
-				size_t hdr_preamble_size)
+			      __u32 non_ctxlen)
 {
 	__u16 neg_count;
 	__u32 nc_offset, size_of_pad_before_neg_ctxts;
@@ -110,12 +109,11 @@ static __u32 get_neg_ctxt_len(struct smb2_sync_hdr *hdr, __u32 len,
 
 	/* Make sure that negotiate contexts start after gss security blob */
 	nc_offset = le32_to_cpu(pneg_rsp->NegotiateContextOffset);
-	if (nc_offset < non_ctxlen - hdr_preamble_size /* RFC1001 len */) {
+	if (nc_offset < non_ctxlen) {
 		printk_once(KERN_WARNING "invalid negotiate context offset\n");
 		return 0;
 	}
-	size_of_pad_before_neg_ctxts = nc_offset -
-					(non_ctxlen - hdr_preamble_size);
+	size_of_pad_before_neg_ctxts = nc_offset - non_ctxlen;
 
 	/* Verify that at least minimal negotiate contexts fit within frame */
 	if (len < nc_offset + (neg_count * sizeof(struct smb2_neg_context))) {
@@ -134,7 +132,7 @@ static __u32 get_neg_ctxt_len(struct smb2_sync_hdr *hdr, __u32 len,
 int
 smb2_check_message(char *buf, unsigned int len, struct TCP_Server_Info *srvr)
 {
-	struct smb2_sync_hdr *shdr = (struct smb2_sync_hdr *)(buf + srvr->vals->header_preamble_size);
+	struct smb2_sync_hdr *shdr = (struct smb2_sync_hdr *)buf;
 	struct smb2_sync_pdu *pdu = (struct smb2_sync_pdu *)shdr;
 	__u64 mid;
 	__u32 clc_len;  /* calculated length */
@@ -183,8 +181,7 @@ smb2_check_message(char *buf, unsigned int len, struct TCP_Server_Info *srvr)
 		}
 		return 1;
 	}
-	if (len > CIFSMaxBufSize + MAX_SMB2_HDR_SIZE -
-	    srvr->vals->header_preamble_size) {
+	if (len > CIFSMaxBufSize + MAX_SMB2_HDR_SIZE) {
 		cifs_dbg(VFS, "SMB length greater than maximum, mid=%llu\n",
 			 mid);
 		return 1;
@@ -227,8 +224,7 @@ smb2_check_message(char *buf, unsigned int len, struct TCP_Server_Info *srvr)
 
 #ifdef CONFIG_CIFS_SMB311
 	if (shdr->Command == SMB2_NEGOTIATE)
-		clc_len += get_neg_ctxt_len(shdr, len, clc_len,
-					    srvr->vals->header_preamble_size);
+		clc_len += get_neg_ctxt_len(shdr, len, clc_len);
 #endif /* SMB311 */
 	if (len != clc_len) {
 		cifs_dbg(FYI, "Calculated size %u length %u mismatch mid %llu\n",
@@ -253,7 +249,7 @@ smb2_check_message(char *buf, unsigned int len, struct TCP_Server_Info *srvr)
 		 */
 		if (clc_len < len) {
 			printk_once(KERN_WARNING
-				"SMB2 server sent bad RFC1001 len %d not %u\n",
+				"SMB2 server sent bad RFC1001 len %d not %d\n",
 				len, clc_len);
 			return 0;
 		}
@@ -401,7 +397,7 @@ smb2_calc_size(void *buf, struct TCP_Server_Info *srvr)
 	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 = srvr->vals->header_preamble_size + le16_to_cpu(shdr->StructureSize);
+	int len = le16_to_cpu(shdr->StructureSize);
 
 	/*
 	 * StructureSize2, ie length of fixed parameter area has already
@@ -422,12 +418,12 @@ smb2_calc_size(void *buf, struct TCP_Server_Info *srvr)
 		 * for some commands, typically those with odd StructureSize,
 		 * so we must add one to the calculation.
 		 */
-		if (offset + srvr->vals->header_preamble_size + 1 < len) {
-			cifs_dbg(VFS, "data area offset %zu overlaps SMB2 header %d\n",
-				 offset + srvr->vals->header_preamble_size + 1, len);
+		if (offset + 1 < len) {
+			cifs_dbg(VFS, "data area offset %d overlaps SMB2 header %d\n",
+				 offset + 1, len);
 			data_length = 0;
 		} else {
-			len = srvr->vals->header_preamble_size + offset + data_length;
+			len = offset + data_length;
 		}
 	}
 calc_size_exit:
diff --git a/fs/cifs/smb2ops.c b/fs/cifs/smb2ops.c
index b0f3bf9b32f9..36e74957b419 100644
--- a/fs/cifs/smb2ops.c
+++ b/fs/cifs/smb2ops.c
@@ -1521,8 +1521,6 @@ smb2_query_symlink(const unsigned int xid, struct cifs_tcon *tcon,
 	unsigned int sub_offset;
 	unsigned int print_len;
 	unsigned int print_offset;
-	struct cifs_ses *ses = tcon->ses;
-	struct TCP_Server_Info *server = ses->server;
 
 	cifs_dbg(FYI, "%s: path: %s\n", __func__, full_path);
 
@@ -1546,7 +1544,7 @@ smb2_query_symlink(const unsigned int xid, struct cifs_tcon *tcon,
 
 	err_buf = err_iov.iov_base;
 	if (le32_to_cpu(err_buf->ByteCount) < sizeof(struct smb2_symlink_err_rsp) ||
-	    err_iov.iov_len + server->vals->header_preamble_size < SMB2_SYMLINK_STRUCT_SIZE) {
+	    err_iov.iov_len < SMB2_SYMLINK_STRUCT_SIZE) {
 		kfree(utf16_path);
 		return -ENOENT;
 	}
@@ -1559,14 +1557,13 @@ 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 (err_iov.iov_len + server->vals->header_preamble_size <
-			SMB2_SYMLINK_STRUCT_SIZE + sub_offset + sub_len) {
+	if (err_iov.iov_len < SMB2_SYMLINK_STRUCT_SIZE + sub_offset + sub_len) {
 		kfree(utf16_path);
 		return -ENOENT;
 	}
 
-	if (err_iov.iov_len + server->vals->header_preamble_size <
-			SMB2_SYMLINK_STRUCT_SIZE + print_offset + print_len) {
+	if (err_iov.iov_len <
+	    SMB2_SYMLINK_STRUCT_SIZE + print_offset + print_len) {
 		kfree(utf16_path);
 		return -ENOENT;
 	}
@@ -2233,7 +2230,7 @@ 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) - 20 - server->vals->header_preamble_size;
+	unsigned int assoc_data_len = sizeof(struct smb2_transform_hdr) - 20;
 	int rc = 0;
 	struct scatterlist *sg;
 	u8 sign[SMB2_SIGNATURE_SIZE] = {};
@@ -2459,7 +2456,7 @@ decrypt_raw_data(struct TCP_Server_Info *server, char *buf,
 	if (rc)
 		return rc;
 
-	memmove(buf + server->vals->header_preamble_size, iov[2].iov_base, buf_data_size);
+	memmove(buf, iov[2].iov_base, buf_data_size);
 
 	server->total_read = buf_data_size + page_data_size;
 
@@ -2565,7 +2562,7 @@ handle_read_data(struct TCP_Server_Info *server, struct mid_q_entry *mid,
 		return 0;
 	}
 
-	data_offset = server->ops->read_data_offset(buf) + server->vals->header_preamble_size;
+	data_offset = server->ops->read_data_offset(buf);
 #ifdef CONFIG_CIFS_SMB_DIRECT
 	use_rdma_mr = rdata->mr;
 #endif
@@ -2661,12 +2658,11 @@ 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 = server->pdu_size + server->vals->header_preamble_size;
+	unsigned int buflen = server->pdu_size;
 	int rc;
 	int i = 0;
 
-	len = min_t(unsigned int, buflen, server->vals->read_rsp_size -
-		server->vals->header_preamble_size +
+	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);
@@ -2674,8 +2670,7 @@ 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) +
-		server->vals->header_preamble_size -
+	len = le32_to_cpu(tr_hdr->OriginalMessageSize) -
 		server->vals->read_rsp_size;
 	npages = DIV_ROUND_UP(len, PAGE_SIZE);
 
@@ -2702,8 +2697,7 @@ 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 -
-			      server->vals->header_preamble_size,
+	rc = decrypt_raw_data(server, buf, server->vals->read_rsp_size,
 			      pages, npages, len);
 	if (rc)
 		goto free_pages;
@@ -2740,7 +2734,7 @@ receive_encrypted_standard(struct TCP_Server_Info *server,
 	struct mid_q_entry *mid_entry;
 
 	/* switch to large buffer if too big for a small one */
-	if (pdu_length + server->vals->header_preamble_size > 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;
@@ -2748,13 +2742,12 @@ 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 +
-				server->vals->header_preamble_size);
+				pdu_length - HEADER_SIZE(server) + 1);
 	if (length < 0)
 		return length;
 	server->total_read += length;
 
-	buf_size = pdu_length + server->vals->header_preamble_size - 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;
@@ -2783,7 +2776,7 @@ smb3_receive_transform(struct TCP_Server_Info *server, struct mid_q_entry **mid)
 	struct smb2_transform_hdr *tr_hdr = (struct smb2_transform_hdr *)buf;
 	unsigned int orig_len = le32_to_cpu(tr_hdr->OriginalMessageSize);
 
-	if (pdu_length + server->vals->header_preamble_size < sizeof(struct smb2_transform_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);
@@ -2792,14 +2785,14 @@ smb3_receive_transform(struct TCP_Server_Info *server, struct mid_q_entry **mid)
 		return -ECONNABORTED;
 	}
 
-	if (pdu_length + server->vals->header_preamble_size < 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 + server->vals->header_preamble_size > 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);
@@ -2810,8 +2803,7 @@ smb3_handle_read_data(struct TCP_Server_Info *server, struct mid_q_entry *mid)
 {
 	char *buf = server->large_buf ? server->bigbuf : server->smallbuf;
 
-	return handle_read_data(server, mid, buf, server->pdu_size +
-				server->vals->header_preamble_size,
+	return handle_read_data(server, mid, buf, server->pdu_size,
 				NULL, 0, 0);
 }
 
diff --git a/fs/cifs/smb2pdu.c b/fs/cifs/smb2pdu.c
index 134bb19b22aa..0ae3ff24ada8 100644
--- a/fs/cifs/smb2pdu.c
+++ b/fs/cifs/smb2pdu.c
@@ -491,8 +491,7 @@ static int smb311_decode_neg_context(struct smb2_negotiate_rsp *rsp,
 		if (len_of_ctxts < sizeof(struct smb2_neg_context))
 			break;
 
-		pctx = (struct smb2_neg_context *)(offset +
-			server->vals->header_preamble_size + (char *)rsp);
+		pctx = (struct smb2_neg_context *)(offset + (char *)rsp);
 		clen = le16_to_cpu(pctx->DataLength);
 		if (clen > len_of_ctxts)
 			break;
@@ -1213,7 +1212,7 @@ SMB2_sess_auth_rawntlmssp_negotiate(struct SMB2_sess_data *sess_data)
 	if (rc)
 		goto out;
 
-	if (offsetof(struct smb2_sess_setup_rsp, Buffer) - ses->server->vals->header_preamble_size !=
+	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));
@@ -1661,7 +1660,7 @@ parse_lease_state(struct TCP_Server_Info *server, struct smb2_create_rsp *rsp,
 	unsigned int remaining;
 	char *name;
 
-	data_offset = (char *)rsp + server->vals->header_preamble_size + 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)) {
@@ -2327,13 +2326,12 @@ SMB2_close(const unsigned int xid, struct cifs_tcon *tcon,
 }
 
 static int
-validate_iov(struct TCP_Server_Info *server,
-	     unsigned int offset, unsigned int buffer_length,
+validate_iov(unsigned int offset, unsigned int buffer_length,
 	     struct kvec *iov, unsigned int min_buf_size)
 {
 	unsigned int smb_len = iov->iov_len;
-	char *end_of_smb = smb_len + server->vals->header_preamble_size + (char *)iov->iov_base;
-	char *begin_of_buf = server->vals->header_preamble_size + offset + (char *)iov->iov_base;
+	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;
 
 
@@ -2363,18 +2361,17 @@ validate_iov(struct TCP_Server_Info *server,
  * Caller must free buffer.
  */
 static int
-validate_and_copy_iov(struct TCP_Server_Info *server,
-		      unsigned int offset, unsigned int buffer_length,
+validate_and_copy_iov(unsigned int offset, unsigned int buffer_length,
 		      struct kvec *iov, unsigned int minbufsize,
 		      char *data)
 {
-	char *begin_of_buf = server->vals->header_preamble_size + offset + (char *)(iov->iov_base);
+	char *begin_of_buf = offset + (char *)iov->iov_base;
 	int rc;
 
 	if (!data)
 		return -EINVAL;
 
-	rc = validate_iov(server, offset, buffer_length, iov, minbufsize);
+	rc = validate_iov(offset, buffer_length, iov, minbufsize);
 	if (rc)
 		return rc;
 
@@ -2454,8 +2451,7 @@ query_info(const unsigned int xid, struct cifs_tcon *tcon,
 		}
 	}
 
-	rc = validate_and_copy_iov(ses->server,
-				   le16_to_cpu(rsp->OutputBufferOffset),
+	rc = validate_and_copy_iov(le16_to_cpu(rsp->OutputBufferOffset),
 				   le32_to_cpu(rsp->OutputBufferLength),
 				   &rsp_iov, min_len, *data);
 
@@ -3406,8 +3402,7 @@ SMB2_query_directory(const unsigned int xid, struct cifs_tcon *tcon,
 		goto qdir_exit;
 	}
 
-	rc = validate_iov(server,
-			  le16_to_cpu(rsp->OutputBufferOffset),
+	rc = validate_iov(le16_to_cpu(rsp->OutputBufferOffset),
 			  le32_to_cpu(rsp->OutputBufferLength), &rsp_iov,
 			  info_buf_size);
 	if (rc)
@@ -3742,7 +3737,7 @@ 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 - server->vals->header_preamble_size);
+		outbuf_len + sizeof(struct smb2_query_info_rsp) - 1);
 
 	iov->iov_base = (char *)req;
 	iov->iov_len = total_len;
@@ -3759,7 +3754,6 @@ SMB2_QFS_info(const unsigned int xid, struct cifs_tcon *tcon,
 	int rc = 0;
 	int resp_buftype;
 	struct cifs_ses *ses = tcon->ses;
-	struct TCP_Server_Info *server = ses->server;
 	struct smb2_fs_full_size_info *info = NULL;
 	int flags = 0;
 
@@ -3780,10 +3774,9 @@ 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 *)(server->vals->header_preamble_size +
+	info = (struct smb2_fs_full_size_info *)(
 		le16_to_cpu(rsp->OutputBufferOffset) + (char *)rsp);
-	rc = validate_iov(server,
-			  le16_to_cpu(rsp->OutputBufferOffset),
+	rc = validate_iov(le16_to_cpu(rsp->OutputBufferOffset),
 			  le32_to_cpu(rsp->OutputBufferLength), &rsp_iov,
 			  sizeof(struct smb2_fs_full_size_info));
 	if (!rc)
@@ -3804,7 +3797,6 @@ SMB2_QFS_attr(const unsigned int xid, struct cifs_tcon *tcon,
 	int rc = 0;
 	int resp_buftype, max_len, min_len;
 	struct cifs_ses *ses = tcon->ses;
-	struct TCP_Server_Info *server = ses->server;
 	unsigned int rsp_len, offset;
 	int flags = 0;
 
@@ -3840,20 +3832,20 @@ 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_iov(server, offset, rsp_len, &rsp_iov, 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, server->vals->header_preamble_size + offset
+		memcpy(&tcon->fsAttrInfo, offset
 			+ (char *)rsp, min_t(unsigned int,
 			rsp_len, max_len));
 	else if (level == FS_DEVICE_INFORMATION)
-		memcpy(&tcon->fsDevInfo, server->vals->header_preamble_size + offset
+		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 *)
-			(server->vals->header_preamble_size + offset + (char *)rsp);
+			(offset + (char *)rsp);
 		tcon->ss_flags = le32_to_cpu(ss_info->Flags);
 		tcon->perf_sector_size =
 			le32_to_cpu(ss_info->PhysicalBytesPerSectorForPerf);