Merge tag '4.14-smb3-multidialect-support-and-fixes-for-stable' of git://git.samba.org/sfrench/cifs-2.6

Pull cifs fixes from Steve French:
 "Convert default dialect to smb2.1 or later to allow connecting to
  Windows 7 for example, also includes some fixes for stable"

* tag '4.14-smb3-multidialect-support-and-fixes-for-stable' of git://git.samba.org/sfrench/cifs-2.6:
  Update version of cifs module
  cifs: hide unused functions
  SMB3: Add support for multidialect negotiate (SMB2.1 and later)
  CIFS/SMB3: Update documentation to reflect SMB3 and various changes
  cifs: check rsp for NULL before dereferencing in SMB2_open

6 files changed, 144 insertions, 21 deletions

diff --git a/fs/cifs/cifsfs.h b/fs/cifs/cifsfs.h
index 30bf89b1fd9a7..5a10e566f0e61 100644
--- a/fs/cifs/cifsfs.h
+++ b/fs/cifs/cifsfs.h
@@ -149,5 +149,5 @@ extern long cifs_ioctl(struct file *filep, unsigned int cmd, unsigned long arg);
 extern const struct export_operations cifs_export_ops;
 #endif /* CONFIG_CIFS_NFSD_EXPORT */
 
-#define CIFS_VERSION   "2.09"
+#define CIFS_VERSION   "2.10"
 #endif				/* _CIFSFS_H */
diff --git a/fs/cifs/cifsglob.h b/fs/cifs/cifsglob.h
index 808486c29f0dc..de5b2e1fcce5f 100644
--- a/fs/cifs/cifsglob.h
+++ b/fs/cifs/cifsglob.h
@@ -188,6 +188,8 @@ enum smb_version {
 #ifdef CONFIG_CIFS_SMB311
 	Smb_311,
 #endif /* SMB311 */
+	Smb_3any,
+	Smb_default,
 	Smb_version_err
 };
 
@@ -1701,6 +1703,10 @@ extern struct smb_version_values smb20_values;
 #define SMB21_VERSION_STRING	"2.1"
 extern struct smb_version_operations smb21_operations;
 extern struct smb_version_values smb21_values;
+#define SMBDEFAULT_VERSION_STRING "default"
+extern struct smb_version_values smbdefault_values;
+#define SMB3ANY_VERSION_STRING "3"
+extern struct smb_version_values smb3any_values;
 #define SMB30_VERSION_STRING	"3.0"
 extern struct smb_version_operations smb30_operations;
 extern struct smb_version_values smb30_values;
diff --git a/fs/cifs/connect.c b/fs/cifs/connect.c
index 5aa2d278ca841..8d38b22afb2b8 100644
--- a/fs/cifs/connect.c
+++ b/fs/cifs/connect.c
@@ -301,6 +301,8 @@ static const match_table_t cifs_smb_version_tokens = {
 	{ Smb_311, SMB311_VERSION_STRING },
 	{ Smb_311, ALT_SMB311_VERSION_STRING },
 #endif /* SMB311 */
+	{ Smb_3any, SMB3ANY_VERSION_STRING },
+	{ Smb_default, SMBDEFAULT_VERSION_STRING },
 	{ Smb_version_err, NULL }
 };
 
@@ -1148,6 +1150,14 @@ cifs_parse_smb_version(char *value, struct smb_vol *vol)
 		vol->vals = &smb311_values;
 		break;
 #endif /* SMB311 */
+	case Smb_3any:
+		vol->ops = &smb30_operations; /* currently identical with 3.0 */
+		vol->vals = &smb3any_values;
+		break;
+	case Smb_default:
+		vol->ops = &smb30_operations; /* currently identical with 3.0 */
+		vol->vals = &smbdefault_values;
+		break;
 	default:
 		cifs_dbg(VFS, "Unknown vers= option specified: %s\n", value);
 		return 1;
@@ -1274,9 +1284,9 @@ cifs_parse_mount_options(const char *mountdata, const char *devname,
 
 	vol->actimeo = CIFS_DEF_ACTIMEO;
 
-	/* FIXME: add autonegotiation for SMB3 or later rather than just SMB3 */
-	vol->ops = &smb30_operations; /* both secure and accepted widely */
-	vol->vals = &smb30_values;
+	/* offer SMB2.1 and later (SMB3 etc). Secure and widely accepted */
+	vol->ops = &smb30_operations;
+	vol->vals = &smbdefault_values;
 
 	vol->echo_interval = SMB_ECHO_INTERVAL_DEFAULT;
 
@@ -1988,11 +1998,10 @@ cifs_parse_mount_options(const char *mountdata, const char *devname,
 
 	if (got_version == false)
 		pr_warn("No dialect specified on mount. Default has changed to "
-			"a more secure dialect, SMB3 (vers=3.0), from CIFS "
+			"a more secure dialect, SMB2.1 or later (e.g. SMB3), from CIFS "
 			"(SMB1). To use the less secure SMB1 dialect to access "
-			"old servers which do not support SMB3 specify vers=1.0"
-			" on mount. For somewhat newer servers such as Windows "
-			"7 try vers=2.1.\n");
+			"old servers which do not support SMB3 (or SMB2.1) specify vers=1.0"
+			" on mount.\n");
 
 	kfree(mountdata_copy);
 	return 0;
@@ -2133,6 +2142,7 @@ static int match_server(struct TCP_Server_Info *server, struct smb_vol *vol)
 	if (vol->nosharesock)
 		return 0;
 
+	/* BB update this for smb3any and default case */
 	if ((server->vals != vol->vals) || (server->ops != vol->ops))
 		return 0;
 
diff --git a/fs/cifs/smb2ops.c b/fs/cifs/smb2ops.c
index fb2934b9b97cf..0dafdbae1f8cb 100644
--- a/fs/cifs/smb2ops.c
+++ b/fs/cifs/smb2ops.c
@@ -426,6 +426,7 @@ smb2_query_file_info(const unsigned int xid, struct cifs_tcon *tcon,
 	return rc;
 }
 
+#ifdef CONFIG_CIFS_XATTR
 static ssize_t
 move_smb2_ea_to_cifs(char *dst, size_t dst_size,
 		     struct smb2_file_full_ea_info *src, size_t src_size,
@@ -613,6 +614,7 @@ smb2_set_ea(const unsigned int xid, struct cifs_tcon *tcon,
 
 	return rc;
 }
+#endif
 
 static bool
 smb2_can_echo(struct TCP_Server_Info *server)
@@ -3110,6 +3112,46 @@ struct smb_version_values smb21_values = {
 	.create_lease_size = sizeof(struct create_lease),
 };
 
+struct smb_version_values smb3any_values = {
+	.version_string = SMB3ANY_VERSION_STRING,
+	.protocol_id = SMB302_PROT_ID, /* doesn't matter, send protocol array */
+	.req_capabilities = SMB2_GLOBAL_CAP_DFS | SMB2_GLOBAL_CAP_LEASING | SMB2_GLOBAL_CAP_LARGE_MTU | SMB2_GLOBAL_CAP_PERSISTENT_HANDLES | SMB2_GLOBAL_CAP_ENCRYPTION,
+	.large_lock_type = 0,
+	.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),
+	.max_header_size = MAX_SMB2_HDR_SIZE,
+	.read_rsp_size = sizeof(struct smb2_read_rsp) - 1,
+	.lock_cmd = SMB2_LOCK,
+	.cap_unix = 0,
+	.cap_nt_find = SMB2_NT_FIND,
+	.cap_large_files = SMB2_LARGE_FILES,
+	.signing_enabled = SMB2_NEGOTIATE_SIGNING_ENABLED | SMB2_NEGOTIATE_SIGNING_REQUIRED,
+	.signing_required = SMB2_NEGOTIATE_SIGNING_REQUIRED,
+	.create_lease_size = sizeof(struct create_lease_v2),
+};
+
+struct smb_version_values smbdefault_values = {
+	.version_string = SMBDEFAULT_VERSION_STRING,
+	.protocol_id = SMB302_PROT_ID, /* doesn't matter, send protocol array */
+	.req_capabilities = SMB2_GLOBAL_CAP_DFS | SMB2_GLOBAL_CAP_LEASING | SMB2_GLOBAL_CAP_LARGE_MTU | SMB2_GLOBAL_CAP_PERSISTENT_HANDLES | SMB2_GLOBAL_CAP_ENCRYPTION,
+	.large_lock_type = 0,
+	.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),
+	.max_header_size = MAX_SMB2_HDR_SIZE,
+	.read_rsp_size = sizeof(struct smb2_read_rsp) - 1,
+	.lock_cmd = SMB2_LOCK,
+	.cap_unix = 0,
+	.cap_nt_find = SMB2_NT_FIND,
+	.cap_large_files = SMB2_LARGE_FILES,
+	.signing_enabled = SMB2_NEGOTIATE_SIGNING_ENABLED | SMB2_NEGOTIATE_SIGNING_REQUIRED,
+	.signing_required = SMB2_NEGOTIATE_SIGNING_REQUIRED,
+	.create_lease_size = sizeof(struct create_lease_v2),
+};
+
 struct smb_version_values smb30_values = {
 	.version_string = SMB30_VERSION_STRING,
 	.protocol_id = SMB30_PROT_ID,
diff --git a/fs/cifs/smb2pdu.c b/fs/cifs/smb2pdu.c
index 5531e7ee1210e..5c16591a128e4 100644
--- a/fs/cifs/smb2pdu.c
+++ b/fs/cifs/smb2pdu.c
@@ -491,10 +491,25 @@ SMB2_negotiate(const unsigned int xid, struct cifs_ses *ses)
 
 	req->hdr.sync_hdr.SessionId = 0;
 
-	req->Dialects[0] = cpu_to_le16(ses->server->vals->protocol_id);
-
-	req->DialectCount = cpu_to_le16(1); /* One vers= at a time for now */
-	inc_rfc1001_len(req, 2);
+	if (strcmp(ses->server->vals->version_string,
+		   SMB3ANY_VERSION_STRING) == 0) {
+		req->Dialects[0] = cpu_to_le16(SMB30_PROT_ID);
+		req->Dialects[1] = cpu_to_le16(SMB302_PROT_ID);
+		req->DialectCount = cpu_to_le16(2);
+		inc_rfc1001_len(req, 4);
+	} else if (strcmp(ses->server->vals->version_string,
+		   SMBDEFAULT_VERSION_STRING) == 0) {
+		req->Dialects[0] = cpu_to_le16(SMB21_PROT_ID);
+		req->Dialects[1] = cpu_to_le16(SMB30_PROT_ID);
+		req->Dialects[2] = cpu_to_le16(SMB302_PROT_ID);
+		req->DialectCount = cpu_to_le16(3);
+		inc_rfc1001_len(req, 6);
+	} else {
+		/* otherwise send specific dialect */
+		req->Dialects[0] = cpu_to_le16(ses->server->vals->protocol_id);
+		req->DialectCount = cpu_to_le16(1);
+		inc_rfc1001_len(req, 2);
+	}
 
 	/* only one of SMB2 signing flags may be set in SMB2 request */
 	if (ses->sign)
@@ -528,16 +543,42 @@ SMB2_negotiate(const unsigned int xid, struct cifs_ses *ses)
 	 */
 	if (rc == -EOPNOTSUPP) {
 		cifs_dbg(VFS, "Dialect not supported by server. Consider "
-			"specifying vers=1.0 or vers=2.1 on mount for accessing"
+			"specifying vers=1.0 or vers=2.0 on mount for accessing"
 			" older servers\n");
 		goto neg_exit;
 	} else if (rc != 0)
 		goto neg_exit;
 
+	if (strcmp(ses->server->vals->version_string,
+		   SMB3ANY_VERSION_STRING) == 0) {
+		if (rsp->DialectRevision == cpu_to_le16(SMB20_PROT_ID)) {
+			cifs_dbg(VFS,
+				"SMB2 dialect returned but not requested\n");
+			return -EIO;
+		} else if (rsp->DialectRevision == cpu_to_le16(SMB21_PROT_ID)) {
+			cifs_dbg(VFS,
+				"SMB2.1 dialect returned but not requested\n");
+			return -EIO;
+		}
+	} else if (strcmp(ses->server->vals->version_string,
+		   SMBDEFAULT_VERSION_STRING) == 0) {
+		if (rsp->DialectRevision == cpu_to_le16(SMB20_PROT_ID)) {
+			cifs_dbg(VFS,
+				"SMB2 dialect returned but not requested\n");
+			return -EIO;
+		} else if (rsp->DialectRevision == cpu_to_le16(SMB21_PROT_ID)) {
+			/* ops set to 3.0 by default for default so update */
+			ses->server->ops = &smb21_operations;
+		}
+	} else if (rsp->DialectRevision != ses->server->vals->protocol_id) {
+		/* if requested single dialect ensure returned dialect matched */
+		cifs_dbg(VFS, "Illegal 0x%x dialect returned: not requested\n",
+			cpu_to_le16(rsp->DialectRevision));
+		return -EIO;
+	}
+
 	cifs_dbg(FYI, "mode 0x%x\n", rsp->SecurityMode);
 
-	/* BB we may eventually want to match the negotiated vs. requested
-	   dialect, even though we are only requesting one at a time */
 	if (rsp->DialectRevision == cpu_to_le16(SMB20_PROT_ID))
 		cifs_dbg(FYI, "negotiated smb2.0 dialect\n");
 	else if (rsp->DialectRevision == cpu_to_le16(SMB21_PROT_ID))
@@ -558,6 +599,8 @@ SMB2_negotiate(const unsigned int xid, struct cifs_ses *ses)
 	}
 	server->dialect = le16_to_cpu(rsp->DialectRevision);
 
+	/* BB: add check that dialect was valid given dialect(s) we asked for */
+
 	/* SMB2 only has an extended negflavor */
 	server->negflavor = CIFS_NEGFLAVOR_EXTENDED;
 	/* set it to the maximum buffer size value we can send with 1 credit */
@@ -606,6 +649,7 @@ int smb3_validate_negotiate(const unsigned int xid, struct cifs_tcon *tcon)
 	struct validate_negotiate_info_req vneg_inbuf;
 	struct validate_negotiate_info_rsp *pneg_rsp;
 	u32 rsplen;
+	u32 inbuflen; /* max of 4 dialects */
 
 	cifs_dbg(FYI, "validate negotiate\n");
 
@@ -634,9 +678,30 @@ int smb3_validate_negotiate(const unsigned int xid, struct cifs_tcon *tcon)
 	else
 		vneg_inbuf.SecurityMode = 0;
 
-	vneg_inbuf.DialectCount = cpu_to_le16(1);
-	vneg_inbuf.Dialects[0] =
-		cpu_to_le16(tcon->ses->server->vals->protocol_id);
+
+	if (strcmp(tcon->ses->server->vals->version_string,
+		SMB3ANY_VERSION_STRING) == 0) {
+		vneg_inbuf.Dialects[0] = cpu_to_le16(SMB30_PROT_ID);
+		vneg_inbuf.Dialects[1] = cpu_to_le16(SMB302_PROT_ID);
+		vneg_inbuf.DialectCount = cpu_to_le16(2);
+		/* structure is big enough for 3 dialects, sending only 2 */
+		inbuflen = sizeof(struct validate_negotiate_info_req) - 2;
+	} else if (strcmp(tcon->ses->server->vals->version_string,
+		SMBDEFAULT_VERSION_STRING) == 0) {
+		vneg_inbuf.Dialects[0] = cpu_to_le16(SMB21_PROT_ID);
+		vneg_inbuf.Dialects[1] = cpu_to_le16(SMB30_PROT_ID);
+		vneg_inbuf.Dialects[2] = cpu_to_le16(SMB302_PROT_ID);
+		vneg_inbuf.DialectCount = cpu_to_le16(3);
+		/* structure is big enough for 3 dialects */
+		inbuflen = sizeof(struct validate_negotiate_info_req);
+	} else {
+		/* otherwise specific dialect was requested */
+		vneg_inbuf.Dialects[0] =
+			cpu_to_le16(tcon->ses->server->vals->protocol_id);
+		vneg_inbuf.DialectCount = cpu_to_le16(1);
+		/* structure is big enough for 3 dialects, sending only 1 */
+		inbuflen = sizeof(struct validate_negotiate_info_req) - 4;
+	}
 
 	rc = SMB2_ioctl(xid, tcon, NO_FILE_ID, NO_FILE_ID,
 		FSCTL_VALIDATE_NEGOTIATE_INFO, true /* is_fsctl */,
@@ -1634,7 +1699,7 @@ SMB2_open(const unsigned int xid, struct cifs_open_parms *oparms, __le16 *path,
 	struct cifs_tcon *tcon = oparms->tcon;
 	struct cifs_ses *ses = tcon->ses;
 	struct kvec iov[4];
-	struct kvec rsp_iov;
+	struct kvec rsp_iov = {NULL, 0};
 	int resp_buftype;
 	int uni_path_len;
 	__le16 *copy_path = NULL;
@@ -1763,7 +1828,7 @@ 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)
+		if (err_buf && rsp)
 			*err_buf = kmemdup(rsp, get_rfc1002_length(rsp) + 4,
 					   GFP_KERNEL);
 		goto creat_exit;
diff --git a/fs/cifs/smb2pdu.h b/fs/cifs/smb2pdu.h
index 393ed5f4e1b65..6c9653a130c8b 100644
--- a/fs/cifs/smb2pdu.h
+++ b/fs/cifs/smb2pdu.h
@@ -716,7 +716,7 @@ struct validate_negotiate_info_req {
 	__u8   Guid[SMB2_CLIENT_GUID_SIZE];
 	__le16 SecurityMode;
 	__le16 DialectCount;
-	__le16 Dialects[1]; /* dialect (someday maybe list) client asked for */
+	__le16 Dialects[3]; /* BB expand this if autonegotiate > 3 dialects */
 } __packed;
 
 struct validate_negotiate_info_rsp {