cifs: update calc_size to take a server argument

and change the smb2 version to take heder_preamble_size into account
instead of hardcoding it as 4 bytes.
Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Steve French <smfrench@gmail.com>

fs/cifs/cifsglob.h

@@ -372,7 +372,7 @@ struct smb_version_operations {
 	int (*close_dir)(const unsigned int, struct cifs_tcon *,
 			 struct cifs_fid *);
 	/* calculate a size of SMB message */
-	unsigned int (*calc_smb_size)(void *);
+	unsigned int (*calc_smb_size)(void *buf, struct TCP_Server_Info *ptcpi);
 	/* check for STATUS_PENDING and process it in a positive case */
 	bool (*is_status_pending)(char *, struct TCP_Server_Info *, int);
 	/* check for STATUS_NETWORK_SESSION_EXPIRED */

fs/cifs/cifsproto.h

@@ -124,7 +124,7 @@ extern void cifs_update_eof(struct cifsInodeInfo *cifsi, loff_t offset,
 			    unsigned int bytes_written);
 extern struct cifsFileInfo *find_writable_file(struct cifsInodeInfo *, bool);
 extern struct cifsFileInfo *find_readable_file(struct cifsInodeInfo *, bool);
-extern unsigned int smbCalcSize(void *buf);
+extern unsigned int smbCalcSize(void *buf, struct TCP_Server_Info *server);
 extern int decode_negTokenInit(unsigned char *security_blob, int length,
 			struct TCP_Server_Info *server);
 extern int cifs_convert_address(struct sockaddr *dst, const char *src, int len);

fs/cifs/misc.c

@@ -342,7 +342,7 @@ checkSMB(char *buf, unsigned int total_read, struct TCP_Server_Info *server)
 	/* otherwise, there is enough to get to the BCC */
 	if (check_smb_hdr(smb))
 		return -EIO;
-	clc_len = smbCalcSize(smb);
+	clc_len = smbCalcSize(smb, server);
 
 	if (4 + rfclen != total_read) {
 		cifs_dbg(VFS, "Length read does not match RFC1001 length %d\n",

fs/cifs/netmisc.c

@@ -903,7 +903,7 @@ map_smb_to_linux_error(char *buf, bool logErr)
  * portion, the number of word parameters and the data portion of the message
  */
 unsigned int
-smbCalcSize(void *buf)
+smbCalcSize(void *buf, struct TCP_Server_Info *server)
 {
 	struct smb_hdr *ptr = (struct smb_hdr *)buf;
 	return (sizeof(struct smb_hdr) + (2 * ptr->WordCount) +

fs/cifs/readdir.c

@@ -650,7 +650,8 @@ find_cifs_entry(const unsigned int xid, struct cifs_tcon *tcon, loff_t pos,
 		char *cur_ent;
 		char *end_of_smb = cfile->srch_inf.ntwrk_buf_start +
 			server->ops->calc_smb_size(
-					cfile->srch_inf.ntwrk_buf_start);
+					cfile->srch_inf.ntwrk_buf_start,
+					server);
 
 		cur_ent = cfile->srch_inf.srch_entries_start;
 		first_entry_in_buffer = cfile->srch_inf.index_of_last_entry
@@ -831,7 +832,8 @@ int cifs_readdir(struct file *file, struct dir_context *ctx)
 	cifs_dbg(FYI, "loop through %d times filling dir for net buf %p\n",
 		 num_to_fill, cifsFile->srch_inf.ntwrk_buf_start);
 	max_len = tcon->ses->server->ops->calc_smb_size(
-			cifsFile->srch_inf.ntwrk_buf_start);
+			cifsFile->srch_inf.ntwrk_buf_start,
+			tcon->ses->server);
 	end_of_smb = cifsFile->srch_inf.ntwrk_buf_start + max_len;
 
 	tmp_buf = kmalloc(UNICODE_NAME_MAX, GFP_KERNEL);

fs/cifs/smb2misc.c

@@ -233,7 +233,7 @@ smb2_check_message(char *buf, unsigned int length, struct TCP_Server_Info *srvr)
 		return 1;
 	}
 
-	clc_len = smb2_calc_size(hdr);
+	clc_len = smb2_calc_size(hdr, srvr);
 
 #ifdef CONFIG_CIFS_SMB311
 	if (shdr->Command == SMB2_NEGOTIATE)
@@ -403,7 +403,7 @@ smb2_get_data_area_len(int *off, int *len, struct smb2_hdr *hdr)
  * portion, the number of word parameters and the data portion of the message.
  */
 unsigned int
-smb2_calc_size(void *buf)
+smb2_calc_size(void *buf, struct TCP_Server_Info *srvr)
 {
 	struct smb2_pdu *pdu = (struct smb2_pdu *)buf;
 	struct smb2_hdr *hdr = &pdu->hdr;
@@ -411,7 +411,7 @@ smb2_calc_size(void *buf)
 	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 = srvr->vals->header_preamble_size + le16_to_cpu(shdr->StructureSize);
 
 	/*
 	 * StructureSize2, ie length of fixed parameter area has already
@@ -433,12 +433,12 @@ smb2_calc_size(void *buf)
 		 * so we must add one to the calculation (and 4 to account for
 		 * the size of the RFC1001 hdr.
 		 */
-		if (offset + 4 + 1 < len) {
-			cifs_dbg(VFS, "data area offset %d overlaps SMB2 header %d\n",
-				 offset + 4 + 1, len);
+		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);
 			data_length = 0;
 		} else {
-			len = 4 + offset + data_length;
+			len = srvr->vals->header_preamble_size + offset + data_length;
 		}
 	}
 calc_size_exit:

fs/cifs/smb2proto.h

@@ -36,7 +36,7 @@ struct smb_rqst;
 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 unsigned int smb2_calc_size(void *buf, struct TCP_Server_Info *server);
 extern char *smb2_get_data_area_len(int *off, int *len, struct smb2_hdr *hdr);
 extern __le16 *cifs_convert_path_to_utf16(const char *from,
 					  struct cifs_sb_info *cifs_sb);