diff mbox

[CIFS] Upgrade default dialect to SMB3 from cifs (SMB1) for improved security

Message ID CAH2r5mt426CkG4DooKqyFRTxn304+vfYZhJ5dOAtm-8vsXOm6w@mail.gmail.com (mailing list archive)
State New, archived
Headers show

Commit Message

Steve French July 8, 2017, 10:47 p.m. UTC
Due to recent publicity about security vulnerabilities in the
much older CIFS dialect, these patches move the default dialect to the
widely accepted (and quite secure) SMB3.0 dialect from the
old default of the CIFS dialect.

We do not want to be encouraging use of less secure dialects,
and both Microsoft and CERT now strongly recommend not using the
older CIFS dialect (SMB Security Best Practices
"recommends disabling SMBv1").

SMB3 is both secure and widely available: in Windows 8 and later,
Samba and Macs.

Users can still choose to explicitly mount with the less secure
dialect (for old servers) by choosing "vers=1.0" on the cifs
mount e.g. to take advantage of Samba's "CIFS POSIX Extensions"

The two patches for this are attached and also at:
https://git.samba.org/?p=sfrench/cifs-2.6.git;a=commit;h=abc018498883b395e34e2ee976bca7cb944f8ecd

and

https://git.samba.org/?p=sfrench/cifs-2.6.git;a=commit;h=c9db9d35a8c85a571d1fa8987703aa0f21de5e32--
Thanks,

Steve
diff mbox

Patch

From c9db9d35a8c85a571d1fa8987703aa0f21de5e32 Mon Sep 17 00:00:00 2001
From: Steve French <smfrench@gmail.com>
Date: Sat, 8 Jul 2017 17:09:33 -0500
Subject: [PATCH 1/2] Remove ifdef since SMB3 (and later) now STRONGLY
 preferred

Remove the CONFIG_CIFS_SMB2 ifdef and Kconfig option since they
must always be on now.

For various security reasons, SMB3 and later are STRONGLY preferred
over CIFS and older dialects, and SMB3 (and later) will now be
the default dialects so we do not want to allow them to be
ifdeffed out.

In the longer term, we may be able to make older CIFS support
disableable in Kconfig with a new set of #ifdef, but we always
want SMB3 and later support enabled.

Signed-off-by: Steven French <smfrench@gmail.com>
Reviewed-by: Pavel Shilovsky <pshilov@microsoft.com>
---
 fs/cifs/Kconfig        | 83 +++++++++++++++++++-------------------------------
 fs/cifs/Makefile       |  7 ++---
 fs/cifs/cifs_unicode.c |  2 --
 fs/cifs/cifs_unicode.h |  2 --
 fs/cifs/cifsfs.c       | 11 ++-----
 fs/cifs/cifsglob.h     | 18 -----------
 fs/cifs/connect.c      | 28 -----------------
 fs/cifs/ioctl.c        |  2 --
 fs/cifs/link.c         |  4 ---
 fs/cifs/misc.c         |  7 +----
 10 files changed, 38 insertions(+), 126 deletions(-)

diff --git a/fs/cifs/Kconfig b/fs/cifs/Kconfig
index afeefe7..f724361 100644
--- a/fs/cifs/Kconfig
+++ b/fs/cifs/Kconfig
@@ -1,5 +1,5 @@ 
 config CIFS
-	tristate "CIFS support (advanced network filesystem, SMBFS successor)"
+	tristate "SMB3 and CIFS support (advanced network filesystem)"
 	depends on INET
 	select NLS
 	select CRYPTO
@@ -10,28 +10,35 @@  config CIFS
 	select CRYPTO_ECB
 	select CRYPTO_DES
 	help
-	  This is the client VFS module for the Common Internet File System
-	  (CIFS) protocol which is the successor to the Server Message Block
-	  (SMB) protocol, the native file sharing mechanism for most early
-	  PC operating systems.  The CIFS protocol is fully supported by
-	  file servers such as Windows 2000 (including Windows 2003, Windows 2008,
-	  NT 4 and Windows XP) as well by Samba (which provides excellent CIFS
+	  This is the client VFS module for the SMB3 family of NAS protocols,
+	  as well as for earlier dialects such as SMB2.1, SMB2 and the
+	  Common Internet File System (CIFS) protocol.  CIFS was the successor
+	  to the original dialect, the Server Message Block (SMB) protocol, the
+	  native file sharing mechanism for most early PC operating systems.
+
+	  The SMB3 protocol is supported by most modern operating systems and
+	  NAS appliances (e.g. Samba, Windows 8, Windows 2012, MacOS).
+	  The older CIFS protocol was included in Windows NT4, 2000 and XP (and
+	  later) as well by Samba (which provides excellent CIFS and SMB3
 	  server support for Linux and many other operating systems). Limited
-	  support for OS/2 and Windows ME and similar servers is provided as
-	  well.
+	  support for OS/2 and Windows ME and similar very old servers is
+	  provided as well.
 
-	  The module also provides optional support for the followon
-	  protocols for CIFS including SMB3, which enables
-	  useful performance and security features (see the description
-	  of CONFIG_CIFS_SMB2).
-
-	  The cifs module provides an advanced network file system
-	  client for mounting to CIFS compliant servers.  It includes
+	  The cifs module provides an advanced network file system client
+	  for mounting to SMB3 (and CIFS) compliant servers.  It includes
 	  support for DFS (hierarchical name space), secure per-user
 	  session establishment via Kerberos or NTLM or NTLMv2,
 	  safe distributed caching (oplock), optional packet
 	  signing, Unicode and other internationalization improvements.
-	  If you need to mount to Samba or Windows from this machine, say Y.
+
+	  In general, the default dialects, SMB3 and later, enable better
+	  performance, security and features, than would be possible with CIFS.
+	  Note that when mounting to Samba, due to the CIFS POSIX extensions,
+	  CIFS mounts can provide slightly better POSIX compatibility
+	  than SMB3 mounts. SMB2/SMB3 mount options are also
+	  slightly simpler (compared to CIFS) due to protocol improvements.
+
+	  If you need to mount to Samba, Macs or Windows from this machine, say Y.
 
 config CIFS_STATS
         bool "CIFS statistics"
@@ -89,7 +96,7 @@  config CIFS_UPCALL
 	  Enables an upcall mechanism for CIFS which accesses userspace helper
 	  utilities to provide SPNEGO packaged (RFC 4178) Kerberos tickets
 	  which are needed to mount to certain secure servers (for which more
-	  secure Kerberos authentication is required). If unsure, say N.
+	  secure Kerberos authentication is required). If unsure, say Y.
 
 config CIFS_XATTR
         bool "CIFS extended attributes"
@@ -105,7 +112,7 @@  config CIFS_XATTR
           (used by some filesystems to store ACLs) is not supported at
           this time.
 
-          If unsure, say N.
+          If unsure, say Y.
 
 config CIFS_POSIX
         bool "CIFS POSIX Extensions"
@@ -125,7 +132,7 @@  config CIFS_ACL
 	  help
 	    Allows fetching CIFS/NTFS ACL from the server.  The DACL blob
 	    is handed over to the application/caller.  See the man
-	    page for getcifsacl for more information.
+	    page for getcifsacl for more information.  If unsure, say Y.
 
 config CIFS_DEBUG
 	bool "Enable CIFS debugging routines"
@@ -148,12 +155,13 @@  config CIFS_DEBUG2
 
 config CIFS_DEBUG_DUMP_KEYS
 	bool "Dump encryption keys for offline decryption (Unsafe)"
-	depends on CIFS_DEBUG && CIFS_SMB2
+	depends on CIFS_DEBUG
 	help
 	   Enabling this will dump the encryption and decryption keys
 	   used to communicate on an encrypted share connection on the
 	   console. This allows Wireshark to decrypt and dissect
 	   encrypted network captures. Enable this carefully.
+	   If unsure, say N.
 
 config CIFS_DFS_UPCALL
 	  bool "DFS feature support"
@@ -166,7 +174,7 @@  config CIFS_DFS_UPCALL
 	    an upcall mechanism for CIFS which contacts userspace helper
 	    utilities to provide server name resolution (host names to
 	    IP addresses) which is needed for implicit mounts of DFS junction
-	    points. If unsure, say N.
+	    points. If unsure, say Y.
 
 config CIFS_NFSD_EXPORT
 	  bool "Allow nfsd to export CIFS file system"
@@ -174,38 +182,9 @@  config CIFS_NFSD_EXPORT
 	  help
 	   Allows NFS server to export a CIFS mounted share (nfsd over cifs)
 
-config CIFS_SMB2
-	bool "SMB2 and SMB3 network file system support"
-	depends on CIFS
-	select KEYS
-	select FSCACHE
-	select DNS_RESOLVER
-	select CRYPTO_AES
-	select CRYPTO_SHA256
-	select CRYPTO_CMAC
-	select CRYPTO_AEAD2
-	select CRYPTO_CCM
-
-	help
-	  This enables support for the Server Message Block version 2
-	  family of protocols, including SMB3.  SMB3 support is
-	  enabled on mount by specifying "vers=3.0" in the mount
-	  options. These protocols are the successors to the popular
-	  CIFS and SMB network file sharing protocols. SMB3 is the
-	  native file sharing mechanism for the more recent
-	  versions of Windows (Windows 8 and Windows 2012 and
-	  later) and Samba server and many others support SMB3 well.
-	  In general SMB3 enables better performance, security
-	  and features, than would be possible with CIFS (Note that
-	  when mounting to Samba, due to the CIFS POSIX extensions,
-	  CIFS mounts can provide slightly better POSIX compatibility
-	  than SMB3 mounts do though). Note that SMB2/SMB3 mount
-	  options are also slightly simpler (compared to CIFS) due
-	  to protocol improvements.
-
 config CIFS_SMB311
 	bool "SMB3.1.1 network file system support (Experimental)"
-	depends on CIFS_SMB2
+	depends on CIFS
 
 	help
 	  This enables experimental support for the newest, SMB3.1.1, dialect.
diff --git a/fs/cifs/Makefile b/fs/cifs/Makefile
index eed7eb0..5e853a3 100644
--- a/fs/cifs/Makefile
+++ b/fs/cifs/Makefile
@@ -6,7 +6,9 @@  obj-$(CONFIG_CIFS) += cifs.o
 cifs-y := cifsfs.o cifssmb.o cifs_debug.o connect.o dir.o file.o inode.o \
 	  link.o misc.o netmisc.o smbencrypt.o transport.o asn1.o \
 	  cifs_unicode.o nterr.o cifsencrypt.o \
-	  readdir.o ioctl.o sess.o export.o smb1ops.o winucase.o
+	  readdir.o ioctl.o sess.o export.o smb1ops.o winucase.o \
+	  smb2ops.o smb2maperror.o smb2transport.o \
+	  smb2misc.o smb2pdu.o smb2inode.o smb2file.o
 
 cifs-$(CONFIG_CIFS_XATTR) += xattr.o
 cifs-$(CONFIG_CIFS_ACL) += cifsacl.o
@@ -16,6 +18,3 @@  cifs-$(CONFIG_CIFS_UPCALL) += cifs_spnego.o
 cifs-$(CONFIG_CIFS_DFS_UPCALL) += dns_resolve.o cifs_dfs_ref.o
 
 cifs-$(CONFIG_CIFS_FSCACHE) += fscache.o cache.o
-
-cifs-$(CONFIG_CIFS_SMB2) += smb2ops.o smb2maperror.o smb2transport.o \
-			    smb2misc.o smb2pdu.o smb2inode.o smb2file.o
diff --git a/fs/cifs/cifs_unicode.c b/fs/cifs/cifs_unicode.c
index e0445e2..b380e08 100644
--- a/fs/cifs/cifs_unicode.c
+++ b/fs/cifs/cifs_unicode.c
@@ -588,7 +588,6 @@  cifsConvertToUTF16(__le16 *target, const char *source, int srclen,
 	return j;
 }
 
-#ifdef CONFIG_CIFS_SMB2
 /*
  * cifs_local_to_utf16_bytes - how long will a string be after conversion?
  * @from - pointer to input string
@@ -647,4 +646,3 @@  cifs_strndup_to_utf16(const char *src, const int maxlen, int *utf16_len,
 	*utf16_len = len;
 	return dst;
 }
-#endif /* CONFIG_CIFS_SMB2 */
diff --git a/fs/cifs/cifs_unicode.h b/fs/cifs/cifs_unicode.h
index 8a79a34..8360b74 100644
--- a/fs/cifs/cifs_unicode.h
+++ b/fs/cifs/cifs_unicode.h
@@ -116,11 +116,9 @@  char *cifs_strndup_from_utf16(const char *src, const int maxlen,
 extern int cifsConvertToUTF16(__le16 *target, const char *source, int maxlen,
 			      const struct nls_table *cp, int mapChars);
 extern int cifs_remap(struct cifs_sb_info *cifs_sb);
-#ifdef CONFIG_CIFS_SMB2
 extern __le16 *cifs_strndup_to_utf16(const char *src, const int maxlen,
 				     int *utf16_len, const struct nls_table *cp,
 				     int remap);
-#endif /* CONFIG_CIFS_SMB2 */
 #endif
 
 wchar_t cifs_toupper(wchar_t in);
diff --git a/fs/cifs/cifsfs.c b/fs/cifs/cifsfs.c
index 9a1667e..bdff696 100644
--- a/fs/cifs/cifsfs.c
+++ b/fs/cifs/cifsfs.c
@@ -51,9 +51,7 @@ 
 #include <linux/key-type.h>
 #include "cifs_spnego.h"
 #include "fscache.h"
-#ifdef CONFIG_CIFS_SMB2
 #include "smb2pdu.h"
-#endif
 
 int cifsFYI = 0;
 bool traceSMB;
@@ -277,9 +275,8 @@  cifs_alloc_inode(struct super_block *sb)
 	cifs_inode->uniqueid = 0;
 	cifs_inode->createtime = 0;
 	cifs_inode->epoch = 0;
-#ifdef CONFIG_CIFS_SMB2
 	generate_random_uuid(cifs_inode->lease_key);
-#endif
+
 	/*
 	 * Can not set i_flags here - they get immediately overwritten to zero
 	 * by the VFS.
@@ -1214,13 +1211,13 @@  static int
 cifs_init_request_bufs(void)
 {
 	size_t max_hdr_size = MAX_CIFS_HDR_SIZE;
-#ifdef CONFIG_CIFS_SMB2
+
 	/*
 	 * SMB2 maximum header size is bigger than CIFS one - no problems to
 	 * allocate some more bytes for CIFS.
 	 */
 	max_hdr_size = MAX_SMB2_HDR_SIZE;
-#endif
+
 	if (CIFSMaxBufSize < 8192) {
 	/* Buffer size can not be smaller than 2 * PATH_MAX since maximum
 	Unicode path name has to fit in any SMB/CIFS path based frames */
@@ -1476,12 +1473,10 @@  MODULE_SOFTDEP("pre: hmac");
 MODULE_SOFTDEP("pre: md4");
 MODULE_SOFTDEP("pre: md5");
 MODULE_SOFTDEP("pre: nls");
-#ifdef CONFIG_CIFS_SMB2
 MODULE_SOFTDEP("pre: aes");
 MODULE_SOFTDEP("pre: cmac");
 MODULE_SOFTDEP("pre: sha256");
 MODULE_SOFTDEP("pre: aead2");
 MODULE_SOFTDEP("pre: ccm");
-#endif /* CONFIG_CIFS_SMB2 */
 module_init(init_cifs)
 module_exit(exit_cifs)
diff --git a/fs/cifs/cifsglob.h b/fs/cifs/cifsglob.h
index fb48251..221693f 100644
--- a/fs/cifs/cifsglob.h
+++ b/fs/cifs/cifsglob.h
@@ -29,9 +29,7 @@ 
 #include <crypto/internal/hash.h>
 #include <linux/scatterlist.h>
 #include <uapi/linux/cifs/cifs_mount.h>
-#ifdef CONFIG_CIFS_SMB2
 #include "smb2pdu.h"
-#endif
 
 #define CIFS_MAGIC_NUMBER 0xFF534D42      /* the first four bytes of SMB PDUs */
 
@@ -612,12 +610,10 @@  struct TCP_Server_Info {
 	__u16 sec_mode;
 	bool sign; /* is signing enabled on this connection? */
 	bool session_estab; /* mark when very first sess is established */
-#ifdef CONFIG_CIFS_SMB2
 	int echo_credits;  /* echo reserved slots */
 	int oplock_credits;  /* oplock break reserved slots */
 	bool echoes:1; /* enable echoes */
 	__u8 client_guid[SMB2_CLIENT_GUID_SIZE]; /* Client GUID */
-#endif
 	u16 dialect; /* dialect index that server chose */
 	bool oplocks:1; /* enable oplocks */
 	unsigned int maxReq;	/* Clients should submit no more */
@@ -661,13 +657,11 @@  struct TCP_Server_Info {
 	atomic_t in_send; /* requests trying to send */
 	atomic_t num_waiters;   /* blocked waiting to get in sendrecv */
 #endif
-#ifdef CONFIG_CIFS_SMB2
 	unsigned int	max_read;
 	unsigned int	max_write;
 	__u8		preauth_hash[512];
 	struct delayed_work reconnect; /* reconnect workqueue job */
 	struct mutex reconnect_mutex; /* prevent simultaneous reconnects */
-#endif /* CONFIG_CIFS_SMB2 */
 	unsigned long echo_interval;
 };
 
@@ -849,13 +843,11 @@  struct cifs_ses {
 	bool sign;		/* is signing required? */
 	bool need_reconnect:1; /* connection reset, uid now invalid */
 	bool domainAuto:1;
-#ifdef CONFIG_CIFS_SMB2
 	__u16 session_flags;
 	__u8 smb3signingkey[SMB3_SIGN_KEY_SIZE];
 	__u8 smb3encryptionkey[SMB3_SIGN_KEY_SIZE];
 	__u8 smb3decryptionkey[SMB3_SIGN_KEY_SIZE];
 	__u8 preauth_hash[512];
-#endif /* CONFIG_CIFS_SMB2 */
 };
 
 static inline bool
@@ -907,12 +899,10 @@  struct cifs_tcon {
 			atomic_t num_acl_get;
 			atomic_t num_acl_set;
 		} cifs_stats;
-#ifdef CONFIG_CIFS_SMB2
 		struct {
 			atomic_t smb2_com_sent[NUMBER_OF_SMB2_COMMANDS];
 			atomic_t smb2_com_failed[NUMBER_OF_SMB2_COMMANDS];
 		} smb2_stats;
-#endif /* CONFIG_CIFS_SMB2 */
 	} stats;
 #ifdef CONFIG_CIFS_STATS2
 	unsigned long long time_writes;
@@ -948,7 +938,6 @@  struct cifs_tcon {
 	bool need_reopen_files:1; /* need to reopen tcon file handles */
 	bool use_resilient:1; /* use resilient instead of durable handles */
 	bool use_persistent:1; /* use persistent instead of durable handles */
-#ifdef CONFIG_CIFS_SMB2
 	bool print:1;		/* set if connection to printer share */
 	__le32 capabilities;
 	__u32 share_flags;
@@ -961,7 +950,6 @@  struct cifs_tcon {
 	__u32 max_chunks;
 	__u32 max_bytes_chunk;
 	__u32 max_bytes_copy;
-#endif /* CONFIG_CIFS_SMB2 */
 #ifdef CONFIG_CIFS_FSCACHE
 	u64 resource_id;		/* server resource id */
 	struct fscache_cookie *fscache;	/* cookie for share */
@@ -1064,12 +1052,10 @@  struct cifs_open_parms {
 
 struct cifs_fid {
 	__u16 netfid;
-#ifdef CONFIG_CIFS_SMB2
 	__u64 persistent_fid;	/* persist file id for smb2 */
 	__u64 volatile_fid;	/* volatile file id for smb2 */
 	__u8 lease_key[SMB2_LEASE_KEY_SIZE];	/* lease key for smb2 */
 	__u8 create_guid[16];
-#endif
 	struct cifs_pending_open *pending_open;
 	unsigned int epoch;
 	bool purge_cache;
@@ -1107,10 +1093,8 @@  struct cifsFileInfo {
 
 struct cifs_io_parms {
 	__u16 netfid;
-#ifdef CONFIG_CIFS_SMB2
 	__u64 persistent_fid;	/* persist file id for smb2 */
 	__u64 volatile_fid;	/* volatile file id for smb2 */
-#endif
 	__u32 pid;
 	__u64 offset;
 	unsigned int length;
@@ -1236,9 +1220,7 @@  struct cifsInodeInfo {
 	u64  server_eof;		/* current file size on server -- protected by i_lock */
 	u64  uniqueid;			/* server inode number */
 	u64  createtime;		/* creation time on server */
-#ifdef CONFIG_CIFS_SMB2
 	__u8 lease_key[SMB2_LEASE_KEY_SIZE];	/* lease key for this inode */
-#endif
 #ifdef CONFIG_CIFS_FSCACHE
 	struct fscache_cookie *fscache;
 #endif
diff --git a/fs/cifs/connect.c b/fs/cifs/connect.c
index c59d77f..6ab261cd 100644
--- a/fs/cifs/connect.c
+++ b/fs/cifs/connect.c
@@ -55,9 +55,7 @@ 
 #include "nterr.h"
 #include "rfc1002pdu.h"
 #include "fscache.h"
-#ifdef CONFIG_CIFS_SMB2
 #include "smb2proto.h"
-#endif
 
 #define CIFS_PORT 445
 #define RFC1001_PORT 139
@@ -341,9 +339,7 @@  cifs_reconnect(struct TCP_Server_Info *server)
 		server->tcpStatus = CifsNeedReconnect;
 	spin_unlock(&GlobalMid_Lock);
 	server->maxBuf = 0;
-#ifdef CONFIG_CIFS_SMB2
 	server->max_read = 0;
-#endif
 
 	cifs_dbg(FYI, "Reconnecting tcp session\n");
 
@@ -1129,7 +1125,6 @@  cifs_parse_smb_version(char *value, struct smb_vol *vol)
 		vol->ops = &smb1_operations;
 		vol->vals = &smb1_values;
 		break;
-#ifdef CONFIG_CIFS_SMB2
 	case Smb_20:
 		vol->ops = &smb20_operations;
 		vol->vals = &smb20_values;
@@ -1152,7 +1147,6 @@  cifs_parse_smb_version(char *value, struct smb_vol *vol)
 		vol->vals = &smb311_values;
 		break;
 #endif /* SMB311 */
-#endif
 	default:
 		cifs_dbg(VFS, "Unknown vers= option specified: %s\n", value);
 		return 1;
@@ -2177,7 +2171,6 @@  cifs_put_tcp_session(struct TCP_Server_Info *server, int from_reconnect)
 
 	cancel_delayed_work_sync(&server->echo);
 
-#ifdef CONFIG_CIFS_SMB2
 	if (from_reconnect)
 		/*
 		 * Avoid deadlock here: reconnect work calls
@@ -2188,7 +2181,6 @@  cifs_put_tcp_session(struct TCP_Server_Info *server, int from_reconnect)
 		cancel_delayed_work(&server->reconnect);
 	else
 		cancel_delayed_work_sync(&server->reconnect);
-#endif
 
 	spin_lock(&GlobalMid_Lock);
 	server->tcpStatus = CifsExiting;
@@ -2254,17 +2246,13 @@  cifs_get_tcp_session(struct smb_vol *volume_info)
 	INIT_LIST_HEAD(&tcp_ses->tcp_ses_list);
 	INIT_LIST_HEAD(&tcp_ses->smb_ses_list);
 	INIT_DELAYED_WORK(&tcp_ses->echo, cifs_echo_request);
-#ifdef CONFIG_CIFS_SMB2
 	INIT_DELAYED_WORK(&tcp_ses->reconnect, smb2_reconnect_server);
 	mutex_init(&tcp_ses->reconnect_mutex);
-#endif
 	memcpy(&tcp_ses->srcaddr, &volume_info->srcaddr,
 	       sizeof(tcp_ses->srcaddr));
 	memcpy(&tcp_ses->dstaddr, &volume_info->dstaddr,
 		sizeof(tcp_ses->dstaddr));
-#ifdef CONFIG_CIFS_SMB2
 	generate_random_uuid(tcp_ses->client_guid);
-#endif
 	/*
 	 * at this point we are the only ones with the pointer
 	 * to the struct since the kernel thread not created yet
@@ -2662,10 +2650,8 @@  static int match_tcon(struct cifs_tcon *tcon, struct smb_vol *volume_info)
 		return 0;
 	if (tcon->seal != volume_info->seal)
 		return 0;
-#ifdef CONFIG_CIFS_SMB2
 	if (tcon->snapshot_time != volume_info->snapshot_time)
 		return 0;
-#endif /* CONFIG_CIFS_SMB2 */
 	return 1;
 }
 
@@ -2740,7 +2726,6 @@  cifs_get_tcon(struct cifs_ses *ses, struct smb_vol *volume_info)
 	}
 
 	if (volume_info->snapshot_time) {
-#ifdef CONFIG_CIFS_SMB2
 		if (ses->server->vals->protocol_id == 0) {
 			cifs_dbg(VFS,
 			     "Use SMB2 or later for snapshot mount option\n");
@@ -2748,11 +2733,6 @@  cifs_get_tcon(struct cifs_ses *ses, struct smb_vol *volume_info)
 			goto out_fail;
 		} else
 			tcon->snapshot_time = volume_info->snapshot_time;
-#else
-		cifs_dbg(VFS, "Snapshot mount option requires SMB2 support\n");
-		rc = -EOPNOTSUPP;
-		goto out_fail;
-#endif /* CONFIG_CIFS_SMB2 */
 	}
 
 	tcon->ses = ses;
@@ -2788,7 +2768,6 @@  cifs_get_tcon(struct cifs_ses *ses, struct smb_vol *volume_info)
 			     "SMB3 or later required for persistent handles\n");
 			rc = -EOPNOTSUPP;
 			goto out_fail;
-#ifdef CONFIG_CIFS_SMB2
 		} else if (ses->server->capabilities &
 			   SMB2_GLOBAL_CAP_PERSISTENT_HANDLES)
 			tcon->use_persistent = true;
@@ -2797,15 +2776,12 @@  cifs_get_tcon(struct cifs_ses *ses, struct smb_vol *volume_info)
 				"Persistent handles not supported on share\n");
 			rc = -EOPNOTSUPP;
 			goto out_fail;
-#endif /* CONFIG_CIFS_SMB2 */
 		}
-#ifdef CONFIG_CIFS_SMB2
 	} else if ((tcon->capabilities & SMB2_SHARE_CAP_CONTINUOUS_AVAILABILITY)
 	     && (ses->server->capabilities & SMB2_GLOBAL_CAP_PERSISTENT_HANDLES)
 	     && (volume_info->nopersistent == false)) {
 		cifs_dbg(FYI, "enabling persistent handles\n");
 		tcon->use_persistent = true;
-#endif /* CONFIG_CIFS_SMB2 */
 	} else if (volume_info->resilient) {
 		if (ses->server->vals->protocol_id == 0) {
 			cifs_dbg(VFS,
@@ -2822,7 +2798,6 @@  cifs_get_tcon(struct cifs_ses *ses, struct smb_vol *volume_info)
 				 "SMB3 or later required for encryption\n");
 			rc = -EOPNOTSUPP;
 			goto out_fail;
-#ifdef CONFIG_CIFS_SMB2
 		} else if (tcon->ses->server->capabilities &
 					SMB2_GLOBAL_CAP_ENCRYPTION)
 			tcon->seal = true;
@@ -2830,7 +2805,6 @@  cifs_get_tcon(struct cifs_ses *ses, struct smb_vol *volume_info)
 			cifs_dbg(VFS, "Encryption is not supported on share\n");
 			rc = -EOPNOTSUPP;
 			goto out_fail;
-#endif /* CONFIG_CIFS_SMB2 */
 		}
 	}
 
@@ -3745,14 +3719,12 @@  cifs_mount(struct cifs_sb_info *cifs_sb, struct smb_vol *volume_info)
 		goto mount_fail_check;
 	}
 
-#ifdef CONFIG_CIFS_SMB2
 	if ((volume_info->persistent == true) && ((ses->server->capabilities &
 		SMB2_GLOBAL_CAP_PERSISTENT_HANDLES) == 0)) {
 		cifs_dbg(VFS, "persistent handles not supported by server\n");
 		rc = -EOPNOTSUPP;
 		goto mount_fail_check;
 	}
-#endif /* CONFIG_CIFS_SMB2*/
 
 	/* search for existing tcon to this server share */
 	tcon = cifs_get_tcon(ses, volume_info);
diff --git a/fs/cifs/ioctl.c b/fs/cifs/ioctl.c
index 76fb091..54f32f9 100644
--- a/fs/cifs/ioctl.c
+++ b/fs/cifs/ioctl.c
@@ -101,7 +101,6 @@  static long smb_mnt_get_fsinfo(unsigned int xid, struct cifs_tcon *tcon,
 	fsinf->fs_attributes = le32_to_cpu(tcon->fsAttrInfo.Attributes);
 	fsinf->max_path_component =
 		le32_to_cpu(tcon->fsAttrInfo.MaxPathNameComponentLength);
-#ifdef CONFIG_CIFS_SMB2
 	fsinf->vol_serial_number = tcon->vol_serial_number;
 	fsinf->vol_create_time = le64_to_cpu(tcon->vol_create_time);
 	fsinf->share_flags = tcon->share_flags;
@@ -110,7 +109,6 @@  static long smb_mnt_get_fsinfo(unsigned int xid, struct cifs_tcon *tcon,
 	fsinf->optimal_sector_size = tcon->perf_sector_size;
 	fsinf->max_bytes_chunk = tcon->max_bytes_chunk;
 	fsinf->maximal_access = tcon->maximal_access;
-#endif /* SMB2 */
 	fsinf->cifs_posix_caps = le64_to_cpu(tcon->fsUnixInfo.Capability);
 
 	if (copy_to_user(arg, fsinf, sizeof(struct smb_mnt_fs_info)))
diff --git a/fs/cifs/link.c b/fs/cifs/link.c
index c4d996f..60b5a11 100644
--- a/fs/cifs/link.c
+++ b/fs/cifs/link.c
@@ -29,9 +29,7 @@ 
 #include "cifs_debug.h"
 #include "cifs_fs_sb.h"
 #include "cifs_unicode.h"
-#ifdef CONFIG_CIFS_SMB2
 #include "smb2proto.h"
-#endif
 
 /*
  * M-F Symlink Functions - Begin
@@ -402,7 +400,6 @@  cifs_create_mf_symlink(unsigned int xid, struct cifs_tcon *tcon,
 /*
  * SMB 2.1/SMB3 Protocol specific functions
  */
-#ifdef CONFIG_CIFS_SMB2
 int
 smb3_query_mf_symlink(unsigned int xid, struct cifs_tcon *tcon,
 		      struct cifs_sb_info *cifs_sb, const unsigned char *path,
@@ -525,7 +522,6 @@  smb3_create_mf_symlink(unsigned int xid, struct cifs_tcon *tcon,
 	kfree(utf16_path);
 	return rc;
 }
-#endif /* CONFIG_CIFS_SMB2 */
 
 /*
  * M-F Symlink Functions - End
diff --git a/fs/cifs/misc.c b/fs/cifs/misc.c
index 3b147dc..227893c 100644
--- a/fs/cifs/misc.c
+++ b/fs/cifs/misc.c
@@ -30,9 +30,7 @@ 
 #include "smberr.h"
 #include "nterr.h"
 #include "cifs_unicode.h"
-#ifdef CONFIG_CIFS_SMB2
 #include "smb2pdu.h"
-#endif
 
 extern mempool_t *cifs_sm_req_poolp;
 extern mempool_t *cifs_req_poolp;
@@ -151,13 +149,12 @@  cifs_buf_get(void)
 	struct smb_hdr *ret_buf = NULL;
 	size_t buf_size = sizeof(struct smb_hdr);
 
-#ifdef CONFIG_CIFS_SMB2
 	/*
 	 * SMB2 header is bigger than CIFS one - no problems to clean some
 	 * more bytes for CIFS.
 	 */
 	buf_size = sizeof(struct smb2_hdr);
-#endif
+
 	/*
 	 * We could use negotiated size instead of max_msgsize -
 	 * but it may be more efficient to always alloc same size
@@ -620,9 +617,7 @@  void
 cifs_add_pending_open_locked(struct cifs_fid *fid, struct tcon_link *tlink,
 			     struct cifs_pending_open *open)
 {
-#ifdef CONFIG_CIFS_SMB2
 	memcpy(open->lease_key, fid->lease_key, SMB2_LEASE_KEY_SIZE);
-#endif
 	open->oplock = CIFS_OPLOCK_NO_CHANGE;
 	open->tlink = tlink;
 	fid->pending_open = open;
-- 
2.7.4