From ac65cb6203e712821a60061b62ad0b24415880a1 Mon Sep 17 00:00:00 2001
From: Colin Ian King <colin.king@canonical.com>
Date: Fri, 9 Feb 2018 12:14:15 +0000
Subject: [PATCH 01/20] CIFS: SMBD: fix spelling mistake: "faield" and "legnth"

Trivial fix to spelling mistake in log_rdma_send and log_rdma_mr
message text.

Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: Steve French <smfrench@gmail.com>
Reviewed-by: Aurelien Aptel <aaptel@suse.com>
---
 fs/cifs/smbdirect.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/fs/cifs/smbdirect.c b/fs/cifs/smbdirect.c
index 91710eb571fb..5aa0b54b32ce 100644
--- a/fs/cifs/smbdirect.c
+++ b/fs/cifs/smbdirect.c
@@ -1025,7 +1025,7 @@ static int smbd_post_send(struct smbd_connection *info,
 
 	for (i = 0; i < request->num_sge; i++) {
 		log_rdma_send(INFO,
-			"rdma_request sge[%d] addr=%llu legnth=%u\n",
+			"rdma_request sge[%d] addr=%llu length=%u\n",
 			i, request->sge[0].addr, request->sge[0].length);
 		ib_dma_sync_single_for_device(
 			info->id->device,
@@ -2295,7 +2295,7 @@ static void smbd_mr_recovery_work(struct work_struct *work)
 				rc = ib_dereg_mr(smbdirect_mr->mr);
 				if (rc) {
 					log_rdma_mr(ERR,
-						"ib_dereg_mr faield rc=%x\n",
+						"ib_dereg_mr failed rc=%x\n",
 						rc);
 					smbd_disconnect_rdma_connection(info);
 				}

From b7a73c84eb96dabd6bb8e9d7c56f796d83efee8e Mon Sep 17 00:00:00 2001
From: Ronnie Sahlberg <lsahlber@redhat.com>
Date: Tue, 13 Feb 2018 15:42:30 +1100
Subject: [PATCH 02/20] cifs: fix memory leak in SMB2_open()

Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Steve French <smfrench@gmail.com>
CC: Stable <stable@vger.kernel.org>
---
 fs/cifs/smb2pdu.c | 8 ++++++--
 1 file changed, 6 insertions(+), 2 deletions(-)

diff --git a/fs/cifs/smb2pdu.c b/fs/cifs/smb2pdu.c
index 63778ac22fd9..ab4c20687cc0 100644
--- a/fs/cifs/smb2pdu.c
+++ b/fs/cifs/smb2pdu.c
@@ -1738,8 +1738,10 @@ SMB2_open(const unsigned int xid, struct cifs_open_parms *oparms, __le16 *path,
 		rc = alloc_path_with_tree_prefix(&copy_path, &copy_size,
 						 &name_len,
 						 tcon->treeName, path);
-		if (rc)
+		if (rc) {
+			cifs_small_buf_release(req);
 			return rc;
+		}
 		req->NameLength = cpu_to_le16(name_len * 2);
 		uni_path_len = copy_size;
 		path = copy_path;
@@ -1750,8 +1752,10 @@ SMB2_open(const unsigned int xid, struct cifs_open_parms *oparms, __le16 *path,
 		if (uni_path_len % 8 != 0) {
 			copy_size = roundup(uni_path_len, 8);
 			copy_path = kzalloc(copy_size, GFP_KERNEL);
-			if (!copy_path)
+			if (!copy_path) {
+				cifs_small_buf_release(req);
 				return -ENOMEM;
+			}
 			memcpy((char *)copy_path, (const char *)path,
 			       uni_path_len);
 			uni_path_len = copy_size;

From 68dbe2f841e0530273d469a4de076ae5147954ce Mon Sep 17 00:00:00 2001
From: Steve French <smfrench@gmail.com>
Date: Tue, 13 Feb 2018 16:52:51 -0600
Subject: [PATCH 03/20] Update TODO list for cifs.ko

Update list of items still TODO in cifs.ko

Signed-off-by: Steve French <smfrench@gmail.com>
---
 Documentation/filesystems/cifs/TODO | 25 ++++++++++++++-----------
 1 file changed, 14 insertions(+), 11 deletions(-)

diff --git a/Documentation/filesystems/cifs/TODO b/Documentation/filesystems/cifs/TODO
index 396ecfd6ff4a..c5adf149b57f 100644
--- a/Documentation/filesystems/cifs/TODO
+++ b/Documentation/filesystems/cifs/TODO
@@ -1,4 +1,4 @@
-Version 2.04 September 13, 2017
+Version 2.11 September 13, 2017
 
 A Partial List of Missing Features
 ==================================
@@ -8,10 +8,10 @@ for visible, important contributions to this module.  Here
 is a partial list of the known problems and missing features:
 
 a) SMB3 (and SMB3.02) missing optional features:
-   - RDMA (started)
-   - multichannel (started)
+   - multichannel (started), integration with RDMA
    - directory leases (improved metadata caching)
-   - T10 copy offload (copy chunk is only mechanism supported)
+   - T10 copy offload (copy chunk, and "Duplicate Extents" ioctl
+     currently the only two server side copy mechanisms supported)
 
 b) improved sparse file support
 
@@ -21,9 +21,8 @@ using Directory Leases
 d) quota support (needs minor kernel change since quota calls
 to make it to network filesystems or deviceless filesystems)
 
-e) Better optimize open to reduce redundant opens (using reference
-counts more) and to improve use of compounding in SMB3 to reduce
-number of roundtrips.
+e) Compounding (in progress) to reduce number of roundtrips, and also
+better optimize open to reduce redundant opens (using reference counts more).
 
 f) Finish inotify support so kde and gnome file list windows
 will autorefresh (partially complete by Asser). Needs minor kernel
@@ -35,7 +34,8 @@ the CIFS statistics (started)
 h) implement support for security and trusted categories of xattrs
 (requires minor protocol extension) to enable better support for SELINUX
 
-i) Implement O_DIRECT flag on open (already supported on mount)
+i) Add support for tree connect contexts (see MS-SMB2) a new SMB3.1.1 protocol
+   feature (may be especially useful for virtualization).
 
 j) Create UID mapping facility so server UIDs can be mapped on a per
 mount or a per server basis to client UIDs or nobody if no mapping
@@ -53,13 +53,16 @@ viewing them.
 
 o) mount helper GUI (to simplify the various configuration options on mount)
 
-p) autonegotiation of dialects (offering more than one dialect ie SMB3.02,
-SMB3, SMB2.1 not just SMB3).
+p) Add support for witness protocol (perhaps ioctl to cifs.ko from user space
+   tool listening on witness protocol RPC) to allow for notification of share
+   move, server failover, and server adapter changes.  And also improve other
+   failover scenarios, e.g. when client knows multiple DFS entries point to
+   different servers, and the server we are connected to has gone down.
 
 q) Allow mount.cifs to be more verbose in reporting errors with dialect
 or unsupported feature errors.
 
-r) updating cifs documentation, and user guid.
+r) updating cifs documentation, and user guide.
 
 s) Addressing bugs found by running a broader set of xfstests in standard
 file system xfstest suite.

From f30e4148b19d38790e68ec277dea3ad1d6c66db6 Mon Sep 17 00:00:00 2001
From: Steve French <smfrench@gmail.com>
Date: Tue, 13 Feb 2018 17:09:28 -0600
Subject: [PATCH 04/20] Update README file for cifs.ko

Remove references to two obsolete /proc/fs/cifs parameters
and update for a few minor SMB3 features.

Signed-off-by: Steve French <smfrench@gmail.com>
---
 Documentation/filesystems/cifs/README | 29 ++++++++++++---------------
 1 file changed, 13 insertions(+), 16 deletions(-)

diff --git a/Documentation/filesystems/cifs/README b/Documentation/filesystems/cifs/README
index a9da51553ba3..99ce3d25003d 100644
--- a/Documentation/filesystems/cifs/README
+++ b/Documentation/filesystems/cifs/README
@@ -11,13 +11,14 @@ Information Foundation.  CIFS and now SMB3 has now become a defacto
 standard for interoperating between Macs and Windows and major NAS appliances.
 
 Please see
+  MS-SMB2 (for detailed SMB2/SMB3/SMB3.1.1 protocol specification)
   http://protocolfreedom.org/ and
   http://samba.org/samba/PFIF/
 for more details.
 
 
 For questions or bug reports please contact:
-    sfrench@samba.org (sfrench@us.ibm.com) 
+    smfrench@gmail.com
 
 See the project page at: https://wiki.samba.org/index.php/LinuxCIFS_utils
 
@@ -37,15 +38,15 @@ Installation instructions:
 =========================
 If you have built the CIFS vfs as module (successfully) simply
 type "make modules_install" (or if you prefer, manually copy the file to
-the modules directory e.g. /lib/modules/2.4.10-4GB/kernel/fs/cifs/cifs.o).
+the modules directory e.g. /lib/modules/2.4.10-4GB/kernel/fs/cifs/cifs.ko).
 
 If you have built the CIFS vfs into the kernel itself, follow the instructions
 for your distribution on how to install a new kernel (usually you
 would simply type "make install").
 
-If you do not have the utility mount.cifs (in the Samba 3.0 source tree and on 
-the CIFS VFS web site) copy it to the same directory in which mount.smbfs and 
-similar files reside (usually /sbin).  Although the helper software is not  
+If you do not have the utility mount.cifs (in the Samba 4.x source tree and on
+the CIFS VFS web site) copy it to the same directory in which mount helpers
+reside (usually /sbin).  Although the helper software is not
 required, mount.cifs is recommended.  Most distros include a "cifs-utils"
 package that includes this utility so it is recommended to install this.
 
@@ -118,10 +119,13 @@ this can become unwieldy when potential mount targets include many
 or  unpredictable UNC names.
 
 Samba Considerations 
-==================== 
-To get the maximum benefit from the CIFS VFS, we recommend using a server that 
-supports the SNIA CIFS Unix Extensions standard (e.g.  Samba 2.2.5 or later or 
-Samba 3.0) but the CIFS vfs works fine with a wide variety of CIFS servers.  
+====================
+Most current servers support SMB2.1 and SMB3 which are more secure,
+but there are useful protocol extensions for the older less secure CIFS
+dialect, so to get the maximum benefit if mounting using the older dialect
+(CIFS/SMB1), we recommend using a server that supports the SNIA CIFS
+Unix Extensions standard (e.g. almost any  version of Samba ie version
+2.2.5 or later) but the CIFS vfs works fine with a wide variety of CIFS servers.
 Note that uid, gid and file permissions will display default values if you do 
 not have a server that supports the Unix extensions for CIFS (such as Samba 
 2.2.5 or later).  To enable the Unix CIFS Extensions in the Samba server, add 
@@ -603,11 +607,6 @@ Stats			Lists summary resource usage information as well as per
 			in the kernel configuration.
 
 Configuration pseudo-files:
-PacketSigningEnabled	If set to one, cifs packet signing is enabled
-			and will be used if the server requires 
-			it.  If set to two, cifs packet signing is
-			required even if the server considers packet
-			signing optional. (default 1)
 SecurityFlags		Flags which control security negotiation and
 			also packet signing. Authentication (may/must)
 			flags (e.g. for NTLM and/or NTLMv2) may be combined with
@@ -666,8 +665,6 @@ traceSMB		If set to one, debug information is logged to the
 LookupCacheEnable	If set to one, inode information is kept cached
 			for one second improving performance of lookups
 			(default 1)
-OplockEnabled		If set to one, safe distributed caching enabled.
-			(default 1)
 LinuxExtensionsEnabled	If set to one then the client will attempt to
 			use the CIFS "UNIX" extensions which are optional
 			protocol enhancements that allow CIFS servers

From 82fb82be05585426405667dd5f0510aa953ba439 Mon Sep 17 00:00:00 2001
From: Aurelien Aptel <aaptel@suse.com>
Date: Fri, 16 Feb 2018 19:19:27 +0100
Subject: [PATCH 05/20] CIFS: refactor crypto shash/sdesc allocation&free

shash and sdesc and always allocated and freed together.
* abstract this in new functions cifs_alloc_hash() and cifs_free_hash().
* make smb2/3 crypto allocation independent from each other.

Signed-off-by: Aurelien Aptel <aaptel@suse.com>
Signed-off-by: Steve French <smfrench@gmail.com>
Reviewed-by: Ronnie Sahlberg <lsahlber@redhat.com>
CC: Stable <stable@vger.kernel.org>
---
 fs/cifs/cifsencrypt.c   | 78 ++++-------------------------------------
 fs/cifs/cifsproto.h     |  5 +++
 fs/cifs/link.c          | 25 +++----------
 fs/cifs/misc.c          | 54 ++++++++++++++++++++++++++++
 fs/cifs/smb2transport.c | 75 ++++++++-------------------------------
 fs/cifs/smbencrypt.c    | 25 +++----------
 6 files changed, 91 insertions(+), 171 deletions(-)

diff --git a/fs/cifs/cifsencrypt.c b/fs/cifs/cifsencrypt.c
index f2b0a7f124da..478a145aa4d0 100644
--- a/fs/cifs/cifsencrypt.c
+++ b/fs/cifs/cifsencrypt.c
@@ -36,37 +36,6 @@
 #include <crypto/skcipher.h>
 #include <crypto/aead.h>
 
-static int
-cifs_crypto_shash_md5_allocate(struct TCP_Server_Info *server)
-{
-	int rc;
-	unsigned int size;
-
-	if (server->secmech.sdescmd5 != NULL)
-		return 0; /* already allocated */
-
-	server->secmech.md5 = crypto_alloc_shash("md5", 0, 0);
-	if (IS_ERR(server->secmech.md5)) {
-		cifs_dbg(VFS, "could not allocate crypto md5\n");
-		rc = PTR_ERR(server->secmech.md5);
-		server->secmech.md5 = NULL;
-		return rc;
-	}
-
-	size = sizeof(struct shash_desc) +
-			crypto_shash_descsize(server->secmech.md5);
-	server->secmech.sdescmd5 = kmalloc(size, GFP_KERNEL);
-	if (!server->secmech.sdescmd5) {
-		crypto_free_shash(server->secmech.md5);
-		server->secmech.md5 = NULL;
-		return -ENOMEM;
-	}
-	server->secmech.sdescmd5->shash.tfm = server->secmech.md5;
-	server->secmech.sdescmd5->shash.flags = 0x0;
-
-	return 0;
-}
-
 int __cifs_calc_signature(struct smb_rqst *rqst,
 			struct TCP_Server_Info *server, char *signature,
 			struct shash_desc *shash)
@@ -132,13 +101,10 @@ static int cifs_calc_signature(struct smb_rqst *rqst,
 	if (!rqst->rq_iov || !signature || !server)
 		return -EINVAL;
 
-	if (!server->secmech.sdescmd5) {
-		rc = cifs_crypto_shash_md5_allocate(server);
-		if (rc) {
-			cifs_dbg(VFS, "%s: Can't alloc md5 crypto\n", __func__);
-			return -1;
-		}
-	}
+	rc = cifs_alloc_hash("md5", &server->secmech.md5,
+			     &server->secmech.sdescmd5);
+	if (rc)
+		return -1;
 
 	rc = crypto_shash_init(&server->secmech.sdescmd5->shash);
 	if (rc) {
@@ -663,37 +629,6 @@ CalcNTLMv2_response(const struct cifs_ses *ses, char *ntlmv2_hash)
 	return rc;
 }
 
-static int crypto_hmacmd5_alloc(struct TCP_Server_Info *server)
-{
-	int rc;
-	unsigned int size;
-
-	/* check if already allocated */
-	if (server->secmech.sdeschmacmd5)
-		return 0;
-
-	server->secmech.hmacmd5 = crypto_alloc_shash("hmac(md5)", 0, 0);
-	if (IS_ERR(server->secmech.hmacmd5)) {
-		cifs_dbg(VFS, "could not allocate crypto hmacmd5\n");
-		rc = PTR_ERR(server->secmech.hmacmd5);
-		server->secmech.hmacmd5 = NULL;
-		return rc;
-	}
-
-	size = sizeof(struct shash_desc) +
-			crypto_shash_descsize(server->secmech.hmacmd5);
-	server->secmech.sdeschmacmd5 = kmalloc(size, GFP_KERNEL);
-	if (!server->secmech.sdeschmacmd5) {
-		crypto_free_shash(server->secmech.hmacmd5);
-		server->secmech.hmacmd5 = NULL;
-		return -ENOMEM;
-	}
-	server->secmech.sdeschmacmd5->shash.tfm = server->secmech.hmacmd5;
-	server->secmech.sdeschmacmd5->shash.flags = 0x0;
-
-	return 0;
-}
-
 int
 setup_ntlmv2_rsp(struct cifs_ses *ses, const struct nls_table *nls_cp)
 {
@@ -757,9 +692,10 @@ setup_ntlmv2_rsp(struct cifs_ses *ses, const struct nls_table *nls_cp)
 
 	mutex_lock(&ses->server->srv_mutex);
 
-	rc = crypto_hmacmd5_alloc(ses->server);
+	rc = cifs_alloc_hash("hmac(md5)",
+			     &ses->server->secmech.hmacmd5,
+			     &ses->server->secmech.sdeschmacmd5);
 	if (rc) {
-		cifs_dbg(VFS, "could not crypto alloc hmacmd5 rc %d\n", rc);
 		goto unlock;
 	}
 
diff --git a/fs/cifs/cifsproto.h b/fs/cifs/cifsproto.h
index 93d565186698..365a414a75e9 100644
--- a/fs/cifs/cifsproto.h
+++ b/fs/cifs/cifsproto.h
@@ -542,4 +542,9 @@ enum securityEnum cifs_select_sectype(struct TCP_Server_Info *,
 struct cifs_aio_ctx *cifs_aio_ctx_alloc(void);
 void cifs_aio_ctx_release(struct kref *refcount);
 int setup_aio_ctx_iter(struct cifs_aio_ctx *ctx, struct iov_iter *iter, int rw);
+
+int cifs_alloc_hash(const char *name, struct crypto_shash **shash,
+		    struct sdesc **sdesc);
+void cifs_free_hash(struct crypto_shash **shash, struct sdesc **sdesc);
+
 #endif			/* _CIFSPROTO_H */
diff --git a/fs/cifs/link.c b/fs/cifs/link.c
index 60b5a11ee11b..889a840172eb 100644
--- a/fs/cifs/link.c
+++ b/fs/cifs/link.c
@@ -50,25 +50,12 @@ static int
 symlink_hash(unsigned int link_len, const char *link_str, u8 *md5_hash)
 {
 	int rc;
-	unsigned int size;
-	struct crypto_shash *md5;
-	struct sdesc *sdescmd5;
+	struct crypto_shash *md5 = NULL;
+	struct sdesc *sdescmd5 = NULL;
 
-	md5 = crypto_alloc_shash("md5", 0, 0);
-	if (IS_ERR(md5)) {
-		rc = PTR_ERR(md5);
-		cifs_dbg(VFS, "%s: Crypto md5 allocation error %d\n",
-			 __func__, rc);
-		return rc;
-	}
-	size = sizeof(struct shash_desc) + crypto_shash_descsize(md5);
-	sdescmd5 = kmalloc(size, GFP_KERNEL);
-	if (!sdescmd5) {
-		rc = -ENOMEM;
+	rc = cifs_alloc_hash("md5", &md5, &sdescmd5);
+	if (rc)
 		goto symlink_hash_err;
-	}
-	sdescmd5->shash.tfm = md5;
-	sdescmd5->shash.flags = 0x0;
 
 	rc = crypto_shash_init(&sdescmd5->shash);
 	if (rc) {
@@ -85,9 +72,7 @@ symlink_hash(unsigned int link_len, const char *link_str, u8 *md5_hash)
 		cifs_dbg(VFS, "%s: Could not generate md5 hash\n", __func__);
 
 symlink_hash_err:
-	crypto_free_shash(md5);
-	kfree(sdescmd5);
-
+	cifs_free_hash(&md5, &sdescmd5);
 	return rc;
 }
 
diff --git a/fs/cifs/misc.c b/fs/cifs/misc.c
index a0dbced4a45c..460084a8eac5 100644
--- a/fs/cifs/misc.c
+++ b/fs/cifs/misc.c
@@ -848,3 +848,57 @@ setup_aio_ctx_iter(struct cifs_aio_ctx *ctx, struct iov_iter *iter, int rw)
 	iov_iter_bvec(&ctx->iter, ITER_BVEC | rw, ctx->bv, npages, ctx->len);
 	return 0;
 }
+
+/**
+ * cifs_alloc_hash - allocate hash and hash context together
+ *
+ * The caller has to make sure @sdesc is initialized to either NULL or
+ * a valid context. Both can be freed via cifs_free_hash().
+ */
+int
+cifs_alloc_hash(const char *name,
+		struct crypto_shash **shash, struct sdesc **sdesc)
+{
+	int rc = 0;
+	size_t size;
+
+	if (*sdesc != NULL)
+		return 0;
+
+	*shash = crypto_alloc_shash(name, 0, 0);
+	if (IS_ERR(*shash)) {
+		cifs_dbg(VFS, "could not allocate crypto %s\n", name);
+		rc = PTR_ERR(*shash);
+		*shash = NULL;
+		*sdesc = NULL;
+		return rc;
+	}
+
+	size = sizeof(struct shash_desc) + crypto_shash_descsize(*shash);
+	*sdesc = kmalloc(size, GFP_KERNEL);
+	if (*sdesc == NULL) {
+		cifs_dbg(VFS, "no memory left to allocate crypto %s\n", name);
+		crypto_free_shash(*shash);
+		*shash = NULL;
+		return -ENOMEM;
+	}
+
+	(*sdesc)->shash.tfm = *shash;
+	(*sdesc)->shash.flags = 0x0;
+	return 0;
+}
+
+/**
+ * cifs_free_hash - free hash and hash context together
+ *
+ * Freeing a NULL hash or context is safe.
+ */
+void
+cifs_free_hash(struct crypto_shash **shash, struct sdesc **sdesc)
+{
+	kfree(*sdesc);
+	*sdesc = NULL;
+	if (*shash)
+		crypto_free_shash(*shash);
+	*shash = NULL;
+}
diff --git a/fs/cifs/smb2transport.c b/fs/cifs/smb2transport.c
index 99493946e2f9..c3c271f557a0 100644
--- a/fs/cifs/smb2transport.c
+++ b/fs/cifs/smb2transport.c
@@ -43,76 +43,31 @@
 static int
 smb2_crypto_shash_allocate(struct TCP_Server_Info *server)
 {
-	int rc;
-	unsigned int size;
-
-	if (server->secmech.sdeschmacsha256 != NULL)
-		return 0; /* already allocated */
-
-	server->secmech.hmacsha256 = crypto_alloc_shash("hmac(sha256)", 0, 0);
-	if (IS_ERR(server->secmech.hmacsha256)) {
-		cifs_dbg(VFS, "could not allocate crypto hmacsha256\n");
-		rc = PTR_ERR(server->secmech.hmacsha256);
-		server->secmech.hmacsha256 = NULL;
-		return rc;
-	}
-
-	size = sizeof(struct shash_desc) +
-			crypto_shash_descsize(server->secmech.hmacsha256);
-	server->secmech.sdeschmacsha256 = kmalloc(size, GFP_KERNEL);
-	if (!server->secmech.sdeschmacsha256) {
-		crypto_free_shash(server->secmech.hmacsha256);
-		server->secmech.hmacsha256 = NULL;
-		return -ENOMEM;
-	}
-	server->secmech.sdeschmacsha256->shash.tfm = server->secmech.hmacsha256;
-	server->secmech.sdeschmacsha256->shash.flags = 0x0;
-
-	return 0;
+	return cifs_alloc_hash("hmac(sha256)",
+			       &server->secmech.hmacsha256,
+			       &server->secmech.sdeschmacsha256);
 }
 
 static int
 smb3_crypto_shash_allocate(struct TCP_Server_Info *server)
 {
-	unsigned int size;
+	struct cifs_secmech *p = &server->secmech;
 	int rc;
 
-	if (server->secmech.sdesccmacaes != NULL)
-		return 0;  /* already allocated */
-
-	rc = smb2_crypto_shash_allocate(server);
+	rc = cifs_alloc_hash("hmac(sha256)",
+			     &p->hmacsha256,
+			     &p->sdeschmacsha256);
 	if (rc)
-		return rc;
+		goto err;
 
-	server->secmech.cmacaes = crypto_alloc_shash("cmac(aes)", 0, 0);
-	if (IS_ERR(server->secmech.cmacaes)) {
-		cifs_dbg(VFS, "could not allocate crypto cmac-aes");
-		kfree(server->secmech.sdeschmacsha256);
-		server->secmech.sdeschmacsha256 = NULL;
-		crypto_free_shash(server->secmech.hmacsha256);
-		server->secmech.hmacsha256 = NULL;
-		rc = PTR_ERR(server->secmech.cmacaes);
-		server->secmech.cmacaes = NULL;
-		return rc;
-	}
-
-	size = sizeof(struct shash_desc) +
-			crypto_shash_descsize(server->secmech.cmacaes);
-	server->secmech.sdesccmacaes = kmalloc(size, GFP_KERNEL);
-	if (!server->secmech.sdesccmacaes) {
-		cifs_dbg(VFS, "%s: Can't alloc cmacaes\n", __func__);
-		kfree(server->secmech.sdeschmacsha256);
-		server->secmech.sdeschmacsha256 = NULL;
-		crypto_free_shash(server->secmech.hmacsha256);
-		crypto_free_shash(server->secmech.cmacaes);
-		server->secmech.hmacsha256 = NULL;
-		server->secmech.cmacaes = NULL;
-		return -ENOMEM;
-	}
-	server->secmech.sdesccmacaes->shash.tfm = server->secmech.cmacaes;
-	server->secmech.sdesccmacaes->shash.flags = 0x0;
+	rc = cifs_alloc_hash("cmac(aes)", &p->cmacaes, &p->sdesccmacaes);
+	if (rc)
+		goto err;
 
 	return 0;
+err:
+	cifs_free_hash(&p->hmacsha256, &p->sdeschmacsha256);
+	return rc;
 }
 
 static struct cifs_ses *
@@ -457,7 +412,7 @@ smb3_calc_signature(struct smb_rqst *rqst, struct TCP_Server_Info *server)
 		cifs_dbg(VFS, "%s: Could not init cmac aes\n", __func__);
 		return rc;
 	}
-	
+
 	rc = __cifs_calc_signature(rqst, server, sigptr,
 				   &server->secmech.sdesccmacaes->shash);
 
diff --git a/fs/cifs/smbencrypt.c b/fs/cifs/smbencrypt.c
index c12bffefa3c9..a0b80ac651a6 100644
--- a/fs/cifs/smbencrypt.c
+++ b/fs/cifs/smbencrypt.c
@@ -121,25 +121,12 @@ int
 mdfour(unsigned char *md4_hash, unsigned char *link_str, int link_len)
 {
 	int rc;
-	unsigned int size;
-	struct crypto_shash *md4;
-	struct sdesc *sdescmd4;
+	struct crypto_shash *md4 = NULL;
+	struct sdesc *sdescmd4 = NULL;
 
-	md4 = crypto_alloc_shash("md4", 0, 0);
-	if (IS_ERR(md4)) {
-		rc = PTR_ERR(md4);
-		cifs_dbg(VFS, "%s: Crypto md4 allocation error %d\n",
-			 __func__, rc);
-		return rc;
-	}
-	size = sizeof(struct shash_desc) + crypto_shash_descsize(md4);
-	sdescmd4 = kmalloc(size, GFP_KERNEL);
-	if (!sdescmd4) {
-		rc = -ENOMEM;
+	rc = cifs_alloc_hash("md4", &md4, &sdescmd4);
+	if (rc)
 		goto mdfour_err;
-	}
-	sdescmd4->shash.tfm = md4;
-	sdescmd4->shash.flags = 0x0;
 
 	rc = crypto_shash_init(&sdescmd4->shash);
 	if (rc) {
@@ -156,9 +143,7 @@ mdfour(unsigned char *md4_hash, unsigned char *link_str, int link_len)
 		cifs_dbg(VFS, "%s: Could not generate md4 hash\n", __func__);
 
 mdfour_err:
-	crypto_free_shash(md4);
-	kfree(sdescmd4);
-
+	cifs_free_hash(&md4, &sdescmd4);
 	return rc;
 }
 

From 5fcd7f3f966f37f3f9a215af4cc1597fe338d0d5 Mon Sep 17 00:00:00 2001
From: Aurelien Aptel <aaptel@suse.com>
Date: Fri, 16 Feb 2018 19:19:28 +0100
Subject: [PATCH 06/20] CIFS: add sha512 secmech

* prepare for SMB3.11 pre-auth integrity
* enable sha512 when SMB311 is enabled in Kconfig
* add sha512 as a soft dependency

Signed-off-by: Aurelien Aptel <aaptel@suse.com>
Signed-off-by: Steve French <smfrench@gmail.com>
CC: Stable <stable@vger.kernel.org>
Reviewed-by: Ronnie Sahlberg <lsahlber@redhat.com>
---
 fs/cifs/Kconfig         |  1 +
 fs/cifs/cifsencrypt.c   |  7 +++++++
 fs/cifs/cifsfs.c        |  1 +
 fs/cifs/cifsglob.h      |  2 ++
 fs/cifs/smb2proto.h     |  3 +++
 fs/cifs/smb2transport.c | 30 ++++++++++++++++++++++++++++++
 6 files changed, 44 insertions(+)

diff --git a/fs/cifs/Kconfig b/fs/cifs/Kconfig
index 687da62daf4e..e901ef6a4813 100644
--- a/fs/cifs/Kconfig
+++ b/fs/cifs/Kconfig
@@ -189,6 +189,7 @@ config CIFS_NFSD_EXPORT
 config CIFS_SMB311
 	bool "SMB3.1.1 network file system support (Experimental)"
 	depends on CIFS
+	select CRYPTO_SHA512
 
 	help
 	  This enables experimental support for the newest, SMB3.1.1, dialect.
diff --git a/fs/cifs/cifsencrypt.c b/fs/cifs/cifsencrypt.c
index 478a145aa4d0..6fa6d459678e 100644
--- a/fs/cifs/cifsencrypt.c
+++ b/fs/cifs/cifsencrypt.c
@@ -829,6 +829,11 @@ cifs_crypto_secmech_release(struct TCP_Server_Info *server)
 		server->secmech.md5 = NULL;
 	}
 
+	if (server->secmech.md5) {
+		crypto_free_shash(server->secmech.sha512);
+		server->secmech.sha512 = NULL;
+	}
+
 	if (server->secmech.hmacmd5) {
 		crypto_free_shash(server->secmech.hmacmd5);
 		server->secmech.hmacmd5 = NULL;
@@ -852,4 +857,6 @@ cifs_crypto_secmech_release(struct TCP_Server_Info *server)
 	server->secmech.sdeschmacmd5 = NULL;
 	kfree(server->secmech.sdescmd5);
 	server->secmech.sdescmd5 = NULL;
+	kfree(server->secmech.sdescsha512);
+	server->secmech.sdescsha512 = NULL;
 }
diff --git a/fs/cifs/cifsfs.c b/fs/cifs/cifsfs.c
index 32cdea67bbfd..f715609b13f3 100644
--- a/fs/cifs/cifsfs.c
+++ b/fs/cifs/cifsfs.c
@@ -1486,6 +1486,7 @@ MODULE_SOFTDEP("pre: nls");
 MODULE_SOFTDEP("pre: aes");
 MODULE_SOFTDEP("pre: cmac");
 MODULE_SOFTDEP("pre: sha256");
+MODULE_SOFTDEP("pre: sha512");
 MODULE_SOFTDEP("pre: aead2");
 MODULE_SOFTDEP("pre: ccm");
 module_init(init_cifs)
diff --git a/fs/cifs/cifsglob.h b/fs/cifs/cifsglob.h
index 48f7c197cd2d..765fc2c9fd91 100644
--- a/fs/cifs/cifsglob.h
+++ b/fs/cifs/cifsglob.h
@@ -130,10 +130,12 @@ struct cifs_secmech {
 	struct crypto_shash *md5; /* md5 hash function */
 	struct crypto_shash *hmacsha256; /* hmac-sha256 hash function */
 	struct crypto_shash *cmacaes; /* block-cipher based MAC function */
+	struct crypto_shash *sha512; /* sha512 hash function */
 	struct sdesc *sdeschmacmd5;  /* ctxt to generate ntlmv2 hash, CR1 */
 	struct sdesc *sdescmd5; /* ctxt to generate cifs/smb signature */
 	struct sdesc *sdeschmacsha256;  /* ctxt to generate smb2 signature */
 	struct sdesc *sdesccmacaes;  /* ctxt to generate smb3 signature */
+	struct sdesc *sdescsha512; /* ctxt to generate smb3.11 signing key */
 	struct crypto_aead *ccmaesencrypt; /* smb3 encryption aead */
 	struct crypto_aead *ccmaesdecrypt; /* smb3 decryption aead */
 };
diff --git a/fs/cifs/smb2proto.h b/fs/cifs/smb2proto.h
index 05287b01f596..3b8e9c2e55bc 100644
--- a/fs/cifs/smb2proto.h
+++ b/fs/cifs/smb2proto.h
@@ -202,4 +202,7 @@ extern int smb3_validate_negotiate(const unsigned int, struct cifs_tcon *);
 
 extern enum securityEnum smb2_select_sectype(struct TCP_Server_Info *,
 					enum securityEnum);
+#ifdef CONFIG_CIFS_SMB311
+extern int smb311_crypto_shash_allocate(struct TCP_Server_Info *server);
+#endif
 #endif			/* _SMB2PROTO_H */
diff --git a/fs/cifs/smb2transport.c b/fs/cifs/smb2transport.c
index c3c271f557a0..bf49cb73b9e6 100644
--- a/fs/cifs/smb2transport.c
+++ b/fs/cifs/smb2transport.c
@@ -70,6 +70,36 @@ err:
 	return rc;
 }
 
+#ifdef CONFIG_CIFS_SMB311
+int
+smb311_crypto_shash_allocate(struct TCP_Server_Info *server)
+{
+	struct cifs_secmech *p = &server->secmech;
+	int rc = 0;
+
+	rc = cifs_alloc_hash("hmac(sha256)",
+			     &p->hmacsha256,
+			     &p->sdeschmacsha256);
+	if (rc)
+		return rc;
+
+	rc = cifs_alloc_hash("cmac(aes)", &p->cmacaes, &p->sdesccmacaes);
+	if (rc)
+		goto err;
+
+	rc = cifs_alloc_hash("sha512", &p->sha512, &p->sdescsha512);
+	if (rc)
+		goto err;
+
+	return 0;
+
+err:
+	cifs_free_hash(&p->cmacaes, &p->sdesccmacaes);
+	cifs_free_hash(&p->hmacsha256, &p->sdeschmacsha256);
+	return rc;
+}
+#endif
+
 static struct cifs_ses *
 smb2_find_smb_ses_unlocked(struct TCP_Server_Info *server, __u64 ses_id)
 {

From 8bd68c6e47abff34e412a0c68cecb4a36bf0198b Mon Sep 17 00:00:00 2001
From: Aurelien Aptel <aaptel@suse.com>
Date: Fri, 16 Feb 2018 19:19:29 +0100
Subject: [PATCH 07/20] CIFS: implement v3.11 preauth integrity

SMB3.11 clients must implement pre-authentification integrity.

* new mechanism to certify requests/responses happening before Tree
  Connect.
* supersedes VALIDATE_NEGOTIATE
* fixes signing for SMB3.11

Signed-off-by: Aurelien Aptel <aaptel@suse.com>
Signed-off-by: Steve French <smfrench@gmail.com>
CC: Stable <stable@vger.kernel.org>
Reviewed-by: Ronnie Sahlberg <lsahlber@redhat.com>
---
 fs/cifs/cifsglob.h  |  5 ++--
 fs/cifs/smb2misc.c  | 64 +++++++++++++++++++++++++++++++++++++++++++++
 fs/cifs/smb2pdu.c   | 25 ++++++++++++++++++
 fs/cifs/smb2pdu.h   |  1 +
 fs/cifs/smb2proto.h |  2 ++
 fs/cifs/transport.c | 17 ++++++++++++
 6 files changed, 112 insertions(+), 2 deletions(-)

diff --git a/fs/cifs/cifsglob.h b/fs/cifs/cifsglob.h
index 765fc2c9fd91..c294093f04d5 100644
--- a/fs/cifs/cifsglob.h
+++ b/fs/cifs/cifsglob.h
@@ -675,7 +675,8 @@ struct TCP_Server_Info {
 	unsigned int	max_read;
 	unsigned int	max_write;
 #ifdef CONFIG_CIFS_SMB311
-	__u8	preauth_sha_hash[64]; /* save initital negprot hash */
+	 /* save initital negprot hash */
+	__u8	preauth_sha_hash[SMB2_PREAUTH_HASH_SIZE];
 #endif /* 3.1.1 */
 	struct delayed_work reconnect; /* reconnect workqueue job */
 	struct mutex reconnect_mutex; /* prevent simultaneous reconnects */
@@ -864,7 +865,7 @@ struct cifs_ses {
 	__u8 smb3encryptionkey[SMB3_SIGN_KEY_SIZE];
 	__u8 smb3decryptionkey[SMB3_SIGN_KEY_SIZE];
 #ifdef CONFIG_CIFS_SMB311
-	__u8 preauth_sha_hash[64];
+	__u8 preauth_sha_hash[SMB2_PREAUTH_HASH_SIZE];
 #endif /* 3.1.1 */
 };
 
diff --git a/fs/cifs/smb2misc.c b/fs/cifs/smb2misc.c
index 76d03abaa38c..da012c3ab700 100644
--- a/fs/cifs/smb2misc.c
+++ b/fs/cifs/smb2misc.c
@@ -706,3 +706,67 @@ smb2_handle_cancelled_mid(char *buffer, struct TCP_Server_Info *server)
 
 	return 0;
 }
+
+#ifdef CONFIG_CIFS_SMB311
+/**
+ * smb311_update_preauth_hash - update @ses hash with the packet data in @iov
+ *
+ * Assumes @iov does not contain the rfc1002 length and iov[0] has the
+ * SMB2 header.
+ */
+int
+smb311_update_preauth_hash(struct cifs_ses *ses, struct kvec *iov, int nvec)
+{
+	int i, rc;
+	struct sdesc *d;
+	struct smb2_sync_hdr *hdr;
+
+	if (ses->server->tcpStatus == CifsGood) {
+		/* skip non smb311 connections */
+		if (ses->server->dialect != SMB311_PROT_ID)
+			return 0;
+
+		/* skip last sess setup response */
+		hdr = (struct smb2_sync_hdr *)iov[0].iov_base;
+		if (hdr->Flags & SMB2_FLAGS_SIGNED)
+			return 0;
+	}
+
+	rc = smb311_crypto_shash_allocate(ses->server);
+	if (rc)
+		return rc;
+
+	d = ses->server->secmech.sdescsha512;
+	rc = crypto_shash_init(&d->shash);
+	if (rc) {
+		cifs_dbg(VFS, "%s: could not init sha512 shash\n", __func__);
+		return rc;
+	}
+
+	rc = crypto_shash_update(&d->shash, ses->preauth_sha_hash,
+				 SMB2_PREAUTH_HASH_SIZE);
+	if (rc) {
+		cifs_dbg(VFS, "%s: could not update sha512 shash\n", __func__);
+		return rc;
+	}
+
+	for (i = 0; i < nvec; i++) {
+		rc = crypto_shash_update(&d->shash,
+					 iov[i].iov_base, iov[i].iov_len);
+		if (rc) {
+			cifs_dbg(VFS, "%s: could not update sha512 shash\n",
+				 __func__);
+			return rc;
+		}
+	}
+
+	rc = crypto_shash_final(&d->shash, ses->preauth_sha_hash);
+	if (rc) {
+		cifs_dbg(VFS, "%s: could not finalize sha512 shash\n",
+			 __func__);
+		return rc;
+	}
+
+	return 0;
+}
+#endif
diff --git a/fs/cifs/smb2pdu.c b/fs/cifs/smb2pdu.c
index ab4c20687cc0..4b6920de2541 100644
--- a/fs/cifs/smb2pdu.c
+++ b/fs/cifs/smb2pdu.c
@@ -453,6 +453,10 @@ SMB2_negotiate(const unsigned int xid, struct cifs_ses *ses)
 		return rc;
 
 	req->sync_hdr.SessionId = 0;
+#ifdef CONFIG_CIFS_SMB311
+	memset(server->preauth_sha_hash, 0, SMB2_PREAUTH_HASH_SIZE);
+	memset(ses->preauth_sha_hash, 0, SMB2_PREAUTH_HASH_SIZE);
+#endif
 
 	if (strcmp(ses->server->vals->version_string,
 		   SMB3ANY_VERSION_STRING) == 0) {
@@ -564,6 +568,15 @@ SMB2_negotiate(const unsigned int xid, struct cifs_ses *ses)
 
 	/* BB: add check that dialect was valid given dialect(s) we asked for */
 
+#ifdef CONFIG_CIFS_SMB311
+	/*
+	 * Keep a copy of the hash after negprot. This hash will be
+	 * the starting hash value for all sessions made from this
+	 * server.
+	 */
+	memcpy(server->preauth_sha_hash, ses->preauth_sha_hash,
+	       SMB2_PREAUTH_HASH_SIZE);
+#endif
 	/* 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 */
@@ -621,6 +634,10 @@ int smb3_validate_negotiate(const unsigned int xid, struct cifs_tcon *tcon)
 		return 0;
 #endif
 
+	/* In SMB3.11 preauth integrity supersedes validate negotiate */
+	if (tcon->ses->server->dialect == SMB311_PROT_ID)
+		return 0;
+
 	/*
 	 * validation ioctl must be signed, so no point sending this if we
 	 * can not sign it (ie are not known user).  Even if signing is not
@@ -1148,6 +1165,14 @@ SMB2_sess_setup(const unsigned int xid, struct cifs_ses *ses,
 	sess_data->buf0_type = CIFS_NO_BUFFER;
 	sess_data->nls_cp = (struct nls_table *) nls_cp;
 
+#ifdef CONFIG_CIFS_SMB311
+	/*
+	 * Initialize the session hash with the server one.
+	 */
+	memcpy(ses->preauth_sha_hash, ses->server->preauth_sha_hash,
+	       SMB2_PREAUTH_HASH_SIZE);
+#endif
+
 	while (sess_data->func)
 		sess_data->func(sess_data);
 
diff --git a/fs/cifs/smb2pdu.h b/fs/cifs/smb2pdu.h
index 2a2b34ccaf49..8b901c69a65a 100644
--- a/fs/cifs/smb2pdu.h
+++ b/fs/cifs/smb2pdu.h
@@ -264,6 +264,7 @@ struct smb2_negotiate_req {
 #define SMB311_SALT_SIZE			32
 /* Hash Algorithm Types */
 #define SMB2_PREAUTH_INTEGRITY_SHA512	cpu_to_le16(0x0001)
+#define SMB2_PREAUTH_HASH_SIZE 64
 
 struct smb2_preauth_neg_context {
 	__le16	ContextType; /* 1 */
diff --git a/fs/cifs/smb2proto.h b/fs/cifs/smb2proto.h
index 3b8e9c2e55bc..cbcce3f7e86f 100644
--- a/fs/cifs/smb2proto.h
+++ b/fs/cifs/smb2proto.h
@@ -204,5 +204,7 @@ extern enum securityEnum smb2_select_sectype(struct TCP_Server_Info *,
 					enum securityEnum);
 #ifdef CONFIG_CIFS_SMB311
 extern int smb311_crypto_shash_allocate(struct TCP_Server_Info *server);
+extern int smb311_update_preauth_hash(struct cifs_ses *ses,
+				      struct kvec *iov, int nvec);
 #endif
 #endif			/* _SMB2PROTO_H */
diff --git a/fs/cifs/transport.c b/fs/cifs/transport.c
index 9779b3292d8e..665661464067 100644
--- a/fs/cifs/transport.c
+++ b/fs/cifs/transport.c
@@ -37,6 +37,7 @@
 #include "cifsglob.h"
 #include "cifsproto.h"
 #include "cifs_debug.h"
+#include "smb2proto.h"
 #include "smbdirect.h"
 
 /* Max number of iovectors we can use off the stack when sending requests. */
@@ -751,6 +752,12 @@ cifs_send_recv(const unsigned int xid, struct cifs_ses *ses,
 	if (rc < 0)
 		goto out;
 
+#ifdef CONFIG_CIFS_SMB311
+	if (ses->status == CifsNew)
+		smb311_update_preauth_hash(ses, rqst->rq_iov+1,
+					   rqst->rq_nvec-1);
+#endif
+
 	if (timeout == CIFS_ASYNC_OP)
 		goto out;
 
@@ -789,6 +796,16 @@ cifs_send_recv(const unsigned int xid, struct cifs_ses *ses,
 	else
 		*resp_buf_type = CIFS_SMALL_BUFFER;
 
+#ifdef CONFIG_CIFS_SMB311
+	if (ses->status == CifsNew) {
+		struct kvec iov = {
+			.iov_base = buf + 4,
+			.iov_len = get_rfc1002_length(buf)
+		};
+		smb311_update_preauth_hash(ses, &iov, 1);
+	}
+#endif
+
 	credits = ses->server->ops->get_credits(midQ);
 
 	rc = ses->server->ops->check_receive(midQ, ses->server,

From 70e80655f58e17a2e38e577e1b4fa7a8c99619a0 Mon Sep 17 00:00:00 2001
From: "Gustavo A. R. Silva" <gustavo@embeddedor.com>
Date: Mon, 19 Feb 2018 11:11:13 -0600
Subject: [PATCH 08/20] CIFS: fix sha512 check in cifs_crypto_secmech_release

It seems this is a copy-paste error and that the proper variable to use
in this particular case is _sha512_ instead of _md5_.

Addresses-Coverity-ID: 1465358 ("Copy-paste error")
Fixes: 1c6614d229e7 ("CIFS: add sha512 secmech")
Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
Reviewed-by: Aurelien Aptel <aaptel@suse.com>
CC: Stable <stable@vger.kernel.org>
Signed-off-by: Steve French <smfrench@gmail.com>
---
 fs/cifs/cifsencrypt.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/fs/cifs/cifsencrypt.c b/fs/cifs/cifsencrypt.c
index 6fa6d459678e..a6ef088e057b 100644
--- a/fs/cifs/cifsencrypt.c
+++ b/fs/cifs/cifsencrypt.c
@@ -829,7 +829,7 @@ cifs_crypto_secmech_release(struct TCP_Server_Info *server)
 		server->secmech.md5 = NULL;
 	}
 
-	if (server->secmech.md5) {
+	if (server->secmech.sha512) {
 		crypto_free_shash(server->secmech.sha512);
 		server->secmech.sha512 = NULL;
 	}

From 262916bc69faf90104aa784d55e10760a4199594 Mon Sep 17 00:00:00 2001
From: Ronnie Sahlberg <lsahlber@redhat.com>
Date: Tue, 20 Feb 2018 12:45:21 +1100
Subject: [PATCH 09/20] fix smb3-encryption breakage when CONFIG_DEBUG_SG=y

We can not use the standard sg_set_buf() fucntion since when
CONFIG_DEBUG_SG=y this adds a check that will BUG_ON for cifs.ko
when we pass it an object from the stack.

Create a new wrapper smb2_sg_set_buf() which avoids doing that particular check
and use it for smb3 encryption instead.

Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Steve French <smfrench@gmail.com>
CC: Stable <stable@vger.kernel.org>
---
 fs/cifs/smb2ops.c | 15 ++++++++++++---
 1 file changed, 12 insertions(+), 3 deletions(-)

diff --git a/fs/cifs/smb2ops.c b/fs/cifs/smb2ops.c
index eb68e2fcc500..dfd6fb02b7a3 100644
--- a/fs/cifs/smb2ops.c
+++ b/fs/cifs/smb2ops.c
@@ -2066,6 +2066,15 @@ fill_transform_hdr(struct smb2_transform_hdr *tr_hdr, struct smb_rqst *old_rq)
 	inc_rfc1001_len(tr_hdr, orig_len);
 }
 
+/* We can not use the normal sg_set_buf() as we will sometimes pass a
+ * stack object as buf.
+ */
+static inline void smb2_sg_set_buf(struct scatterlist *sg, const void *buf,
+				   unsigned int buflen)
+{
+	sg_set_page(sg, virt_to_page(buf), buflen, offset_in_page(buf));
+}
+
 static struct scatterlist *
 init_sg(struct smb_rqst *rqst, u8 *sign)
 {
@@ -2080,16 +2089,16 @@ 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);
+	smb2_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,
+		smb2_sg_set_buf(&sg[i], rqst->rq_iov[i].iov_base,
 						rqst->rq_iov[i].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;
 		sg_set_page(&sg[i], rqst->rq_pages[j], len, 0);
 	}
-	sg_set_buf(&sg[sg_len - 1], sign, SMB2_SIGNATURE_SIZE);
+	smb2_sg_set_buf(&sg[sg_len - 1], sign, SMB2_SIGNATURE_SIZE);
 	return sg;
 }
 

From 6188f28bf608ddecc2377663b0f2f709440c19ba Mon Sep 17 00:00:00 2001
From: Steve French <smfrench@gmail.com>
Date: Tue, 13 Mar 2018 02:29:36 -0500
Subject: [PATCH 10/20] Tree connect for SMB3.1.1 must be signed for
 non-encrypted shares

SMB3.1.1 tree connect was only being signed when signing was mandatory
but needs to always be signed (for non-guest users).

See MS-SMB2 section 3.2.4.1.1

Signed-off-by: Steve French <smfrench@gmail.com>
Reviewed-by: Pavel Shilovsky <pshilov@microsoft.com>
CC: Stable <stable@vger.kernel.org>
---
 fs/cifs/smb2pdu.c | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/fs/cifs/smb2pdu.c b/fs/cifs/smb2pdu.c
index 4b6920de2541..af62c75b17c4 100644
--- a/fs/cifs/smb2pdu.c
+++ b/fs/cifs/smb2pdu.c
@@ -1305,6 +1305,11 @@ SMB2_tcon(const unsigned int xid, struct cifs_ses *ses, const char *tree,
 	iov[1].iov_base = unc_path;
 	iov[1].iov_len = unc_path_len;
 
+	/* 3.11 tcon req must be signed if not encrypted. See MS-SMB2 3.2.4.1.1 */
+	if ((ses->server->dialect == SMB311_PROT_ID) &&
+	    !encryption_required(tcon))
+		req->sync_hdr.Flags |= SMB2_FLAGS_SIGNED;
+
 	rc = smb2_send_recv(xid, ses, iov, 2, &resp_buftype, flags, &rsp_iov);
 	cifs_small_buf_release(req);
 	rsp = (struct smb2_tree_connect_rsp *)rsp_iov.iov_base;

From d68f353fc9d086a88331d6714e437bd7f4f77f48 Mon Sep 17 00:00:00 2001
From: Steve French <smfrench@gmail.com>
Date: Tue, 13 Mar 2018 02:35:01 -0500
Subject: [PATCH 11/20] SMB3.1.1 dialect is no longer experimental

SMB3.1.1 is a very important dialect, with much improved security.
We can remove the ExPERIMENTAL comments about it. It is widely
supported by servers.

Signed-off-by: Steve French <smfrench@gmail.com>
CC: Stable <stable@vger.kernel.org>
---
 fs/cifs/Kconfig | 7 +++----
 1 file changed, 3 insertions(+), 4 deletions(-)

diff --git a/fs/cifs/Kconfig b/fs/cifs/Kconfig
index e901ef6a4813..741749a98614 100644
--- a/fs/cifs/Kconfig
+++ b/fs/cifs/Kconfig
@@ -187,14 +187,13 @@ config CIFS_NFSD_EXPORT
 	   Allows NFS server to export a CIFS mounted share (nfsd over cifs)
 
 config CIFS_SMB311
-	bool "SMB3.1.1 network file system support (Experimental)"
+	bool "SMB3.1.1 network file system support"
 	depends on CIFS
 	select CRYPTO_SHA512
 
 	help
-	  This enables experimental support for the newest, SMB3.1.1, dialect.
-	  This dialect includes improved security negotiation features.
-	  If unsure, say N
+	  This enables support for the newest, and most secure dialect, SMB3.11.
+	  If unsure, say Y
 
 config CIFS_SMB_DIRECT
 	bool "SMB Direct support (Experimental)"

From 31cd106bb141b54ba4db5c1078c3f58f0c6e8dfa Mon Sep 17 00:00:00 2001
From: Phillip Potter <phil@philpotter.co.uk>
Date: Sat, 17 Mar 2018 21:06:56 +0000
Subject: [PATCH 12/20] fs: cifs: Replace _free_xid call in cifs_root_iget
 function

Modify end of cifs_root_iget function in fs/cifs/inode.c to call
free_xid(xid) instead of _free_xid(xid), thereby allowing debug
notification of this action when enabled.

Signed-off-by: Phillip Potter <phil@philpotter.co.uk>
Signed-off-by: Steve French <smfrench@gmail.com>
---
 fs/cifs/inode.c | 5 +----
 1 file changed, 1 insertion(+), 4 deletions(-)

diff --git a/fs/cifs/inode.c b/fs/cifs/inode.c
index 8f9a8cc7cc62..c98a852180b1 100644
--- a/fs/cifs/inode.c
+++ b/fs/cifs/inode.c
@@ -1066,10 +1066,7 @@ iget_no_retry:
 
 out:
 	kfree(path);
-	/* can not call macro free_xid here since in a void func
-	 * TODO: This is no longer true
-	 */
-	_free_xid(xid);
+	free_xid(xid);
 	return inode;
 }
 

From 2564f2ff83975e05dbd2f13301f7147b63e67c91 Mon Sep 17 00:00:00 2001
From: Steve French <smfrench@gmail.com>
Date: Wed, 21 Mar 2018 23:16:36 -0500
Subject: [PATCH 13/20] Don't log expected error on DFS referral request

STATUS_FS_DRIVER_REQUIRED is expected when DFS is not turned
on on the server.  Do not log it on DFS referral response.
It clutters the dmesg log unnecessarily at mount time.

Signed-off-by: Steve French <smfrench@gmail.com>
Reviewed-by: Aurelien Aptel <aaptel@suse.com
Reviewed-by: Ronnie sahlberg <lsahlber@redhat.com>
---
 fs/cifs/smb2maperror.c | 2 +-
 fs/cifs/smb2ops.c      | 2 +-
 2 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/fs/cifs/smb2maperror.c b/fs/cifs/smb2maperror.c
index 62c88dfed57b..3bfc9c990724 100644
--- a/fs/cifs/smb2maperror.c
+++ b/fs/cifs/smb2maperror.c
@@ -745,7 +745,7 @@ static const struct status_to_posix_error smb2_error_map_table[] = {
 	"STATUS_NOLOGON_SERVER_TRUST_ACCOUNT"},
 	{STATUS_DOMAIN_TRUST_INCONSISTENT, -EIO,
 	"STATUS_DOMAIN_TRUST_INCONSISTENT"},
-	{STATUS_FS_DRIVER_REQUIRED, -EIO, "STATUS_FS_DRIVER_REQUIRED"},
+	{STATUS_FS_DRIVER_REQUIRED, -EOPNOTSUPP, "STATUS_FS_DRIVER_REQUIRED"},
 	{STATUS_IMAGE_ALREADY_LOADED_AS_DLL, -EIO,
 	"STATUS_IMAGE_ALREADY_LOADED_AS_DLL"},
 	{STATUS_NETWORK_OPEN_RESTRICTION, -EIO,
diff --git a/fs/cifs/smb2ops.c b/fs/cifs/smb2ops.c
index dfd6fb02b7a3..c5777783f313 100644
--- a/fs/cifs/smb2ops.c
+++ b/fs/cifs/smb2ops.c
@@ -1412,7 +1412,7 @@ smb2_get_dfs_refer(const unsigned int xid, struct cifs_ses *ses,
 	} while (rc == -EAGAIN);
 
 	if (rc) {
-		if (rc != -ENOENT)
+		if ((rc != -ENOENT) && (rc != -EOPNOTSUPP))
 			cifs_dbg(VFS, "ioctl error in smb2_get_dfs_refer rc=%d\n", rc);
 		goto out;
 	}

From 2a18287b54f8654d9835cddfc80a12fd73162fc0 Mon Sep 17 00:00:00 2001
From: Steve French <stfrench@microsoft.com>
Date: Thu, 29 Mar 2018 12:16:34 -0500
Subject: [PATCH 14/20] Don't log confusing message on reconnect by default

Change the following message (which can occur on reconnect) from
a warning to an FYI message.  It is confusing to users.

   [58360.523634] CIFS VFS: Free previous auth_key.response = 00000000a91cdc84

By default this message won't show up on reconnect unless the user bumps
up the log level to include FYI messages.

Signed-off-by: Steve French <smfrench@gmail.com>
Reviewed-by: Pavel Shilovsky <pshilov@microsoft.com>
---
 fs/cifs/connect.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/fs/cifs/connect.c b/fs/cifs/connect.c
index a726f524fb84..4af41b01e0e9 100644
--- a/fs/cifs/connect.c
+++ b/fs/cifs/connect.c
@@ -4306,7 +4306,7 @@ cifs_setup_session(const unsigned int xid, struct cifs_ses *ses,
 		 server->sec_mode, server->capabilities, server->timeAdj);
 
 	if (ses->auth_key.response) {
-		cifs_dbg(VFS, "Free previous auth_key.response = %p\n",
+		cifs_dbg(FYI, "Free previous auth_key.response = %p\n",
 			 ses->auth_key.response);
 		kfree(ses->auth_key.response);
 		ses->auth_key.response = NULL;

From 48f238a79f668f8ff013024d83010de551833d7f Mon Sep 17 00:00:00 2001
From: Long Li <longli@microsoft.com>
Date: Fri, 30 Mar 2018 15:16:35 -0700
Subject: [PATCH 15/20] cifs: smbd: avoid reconnect lockup

During transport reconnect, other processes may have registered memory
and blocked on transport. This creates a deadlock situation because the
transport resources can't be freed, and reconnect is blocked.

Fix this by returning to upper layer on timeout. Before returning,
transport status is set to reconnecting so other processes will release
memory registration resources.

Upper layer will retry the reconnect. This is not in fast I/O path so
setting the timeout to 5 seconds.

Signed-off-by: Long Li <longli@microsoft.com>
Signed-off-by: Steve French <smfrench@gmail.com>
Reviewed-by: Ronnie Sahlberg <lsahlber@redhat.com>
CC: Stable <stable@vger.kernel.org>
---
 fs/cifs/smbdirect.c | 12 ++++++++----
 1 file changed, 8 insertions(+), 4 deletions(-)

diff --git a/fs/cifs/smbdirect.c b/fs/cifs/smbdirect.c
index 5aa0b54b32ce..3f7883e2e14d 100644
--- a/fs/cifs/smbdirect.c
+++ b/fs/cifs/smbdirect.c
@@ -1498,8 +1498,8 @@ int smbd_reconnect(struct TCP_Server_Info *server)
 	log_rdma_event(INFO, "reconnecting rdma session\n");
 
 	if (!server->smbd_conn) {
-		log_rdma_event(ERR, "rdma session already destroyed\n");
-		return -EINVAL;
+		log_rdma_event(INFO, "rdma session already destroyed\n");
+		goto create_conn;
 	}
 
 	/*
@@ -1512,15 +1512,19 @@ int smbd_reconnect(struct TCP_Server_Info *server)
 	}
 
 	/* wait until the transport is destroyed */
-	wait_event(server->smbd_conn->wait_destroy,
-		server->smbd_conn->transport_status == SMBD_DESTROYED);
+	if (!wait_event_timeout(server->smbd_conn->wait_destroy,
+		server->smbd_conn->transport_status == SMBD_DESTROYED, 5*HZ))
+		return -EAGAIN;
 
 	destroy_workqueue(server->smbd_conn->workqueue);
 	kfree(server->smbd_conn);
 
+create_conn:
 	log_rdma_event(INFO, "creating rdma session\n");
 	server->smbd_conn = smbd_get_connection(
 		server, (struct sockaddr *) &server->dstaddr);
+	log_rdma_event(INFO, "created rdma session info=%p\n",
+		server->smbd_conn);
 
 	return server->smbd_conn ? 0 : -ENOENT;
 }

From 21a4e14aaedbc85f203d37e56cb26235b22b43f6 Mon Sep 17 00:00:00 2001
From: Long Li <longli@microsoft.com>
Date: Fri, 30 Mar 2018 15:16:36 -0700
Subject: [PATCH 16/20] cifs: smbd: disconnect transport on RDMA errors

On RDMA errors, transport should disconnect the RDMA CM connection. This
will notify the upper layer, and it will attempt transport reconnect.

Signed-off-by: Long Li <longli@microsoft.com>
Signed-off-by: Steve French <smfrench@gmail.com>
Reviewed-by: Ronnie Sahlberg <lsahlber@redhat.com>
CC: Stable <stable@vger.kernel.org>
---
 fs/cifs/smbdirect.c | 7 ++++++-
 1 file changed, 6 insertions(+), 1 deletion(-)

diff --git a/fs/cifs/smbdirect.c b/fs/cifs/smbdirect.c
index 3f7883e2e14d..5008af546dd1 100644
--- a/fs/cifs/smbdirect.c
+++ b/fs/cifs/smbdirect.c
@@ -862,6 +862,8 @@ static int smbd_post_send_negotiate_req(struct smbd_connection *info)
 	ib_dma_unmap_single(info->id->device, request->sge[0].addr,
 		request->sge[0].length, DMA_TO_DEVICE);
 
+	smbd_disconnect_rdma_connection(info);
+
 dma_mapping_failed:
 	mempool_free(request, info->request_mempool);
 	return rc;
@@ -1061,6 +1063,7 @@ static int smbd_post_send(struct smbd_connection *info,
 			if (atomic_dec_and_test(&info->send_pending))
 				wake_up(&info->wait_send_pending);
 		}
+		smbd_disconnect_rdma_connection(info);
 	} else
 		/* Reset timer for idle connection after packet is sent */
 		mod_delayed_work(info->workqueue, &info->idle_timer_work,
@@ -1202,7 +1205,7 @@ static int smbd_post_recv(
 	if (rc) {
 		ib_dma_unmap_single(info->id->device, response->sge.addr,
 				    response->sge.length, DMA_FROM_DEVICE);
-
+		smbd_disconnect_rdma_connection(info);
 		log_rdma_recv(ERR, "ib_post_recv failed rc=%d\n", rc);
 	}
 
@@ -2546,6 +2549,8 @@ dma_map_error:
 	if (atomic_dec_and_test(&info->mr_used_count))
 		wake_up(&info->wait_for_mr_cleanup);
 
+	smbd_disconnect_rdma_connection(info);
+
 	return NULL;
 }
 

From 93012bf984163f6616d1ab606a7cd86095c052c6 Mon Sep 17 00:00:00 2001
From: Ronnie Sahlberg <lsahlber@redhat.com>
Date: Sat, 31 Mar 2018 11:45:31 +1100
Subject: [PATCH 17/20] cifs: add server->vals->header_preamble_size

This variable is set to 4 for all protocol versions and replaces
the hardcoded constant 4 throughought the code.
This will later be updated to reflect whether a response packet
has a 4 byte length preamble or not once we start removing this
field from the SMB2+ dialects.

Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Reviewed-by: Pavel Shilovsky <pshilov@microsoft.com>
---
 fs/cifs/cifsglob.h  |  1 +
 fs/cifs/cifssmb.c   |  6 +++--
 fs/cifs/connect.c   | 16 ++++++++----
 fs/cifs/smb1ops.c   |  1 +
 fs/cifs/smb2misc.c  | 19 ++++++++-------
 fs/cifs/smb2ops.c   | 59 ++++++++++++++++++++++++++++-----------------
 fs/cifs/smb2pdu.c   | 15 +++++++-----
 fs/cifs/transport.c |  3 ++-
 8 files changed, 75 insertions(+), 45 deletions(-)

diff --git a/fs/cifs/cifsglob.h b/fs/cifs/cifsglob.h
index c294093f04d5..3e3f86841372 100644
--- a/fs/cifs/cifsglob.h
+++ b/fs/cifs/cifsglob.h
@@ -468,6 +468,7 @@ 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;
diff --git a/fs/cifs/cifssmb.c b/fs/cifs/cifssmb.c
index 9ceebf30eb22..59c09a596c0a 100644
--- a/fs/cifs/cifssmb.c
+++ b/fs/cifs/cifssmb.c
@@ -1454,7 +1454,8 @@ 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 = get_rfc1002_length(buf) +
+		server->vals->header_preamble_size;
 	bool use_rdma_mr = false;
 
 	cifs_dbg(FYI, "%s: mid=%llu offset=%llu bytes=%u\n",
@@ -1504,7 +1505,8 @@ 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 4af41b01e0e9..4e0808f40195 100644
--- a/fs/cifs/connect.c
+++ b/fs/cifs/connect.c
@@ -775,7 +775,8 @@ standard_receive3(struct TCP_Server_Info *server, struct mid_q_entry *mid)
 	unsigned int pdu_length = get_rfc1002_length(buf);
 
 	/* 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);
@@ -791,7 +792,9 @@ 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);
+				       pdu_length - HEADER_SIZE(server) + 1
+				       + server->vals->header_preamble_size);
+
 	if (length < 0)
 		return length;
 	server->total_read += length;
@@ -884,7 +887,8 @@ cifs_demultiplex_thread(void *p)
 			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);
@@ -893,8 +897,10 @@ 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;
diff --git a/fs/cifs/smb1ops.c b/fs/cifs/smb1ops.c
index 3d495e440c87..aff8ce8ba34d 100644
--- a/fs/cifs/smb1ops.c
+++ b/fs/cifs/smb1ops.c
@@ -1122,6 +1122,7 @@ 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/smb2misc.c b/fs/cifs/smb2misc.c
index da012c3ab700..dfa5d9f4e00b 100644
--- a/fs/cifs/smb2misc.c
+++ b/fs/cifs/smb2misc.c
@@ -150,7 +150,8 @@ smb2_check_message(char *buf, unsigned int length, struct TCP_Server_Info *srvr)
 		}
 		return 1;
 	}
-	if (len > CIFSMaxBufSize + MAX_SMB2_HDR_SIZE - 4) {
+	if (len > CIFSMaxBufSize + MAX_SMB2_HDR_SIZE -
+	    srvr->vals->header_preamble_size) {
 		cifs_dbg(VFS, "SMB length greater than maximum, mid=%llu\n",
 			 mid);
 		return 1;
@@ -189,26 +190,26 @@ smb2_check_message(char *buf, unsigned int length, struct TCP_Server_Info *srvr)
 		}
 	}
 
-	if (4 + len != length) {
+	if (srvr->vals->header_preamble_size + len != length) {
 		cifs_dbg(VFS, "Total length %u RFC1002 length %u mismatch mid %llu\n",
-			 length, 4 + len, mid);
+			 length, srvr->vals->header_preamble_size + len, mid);
 		return 1;
 	}
 
 	clc_len = smb2_calc_size(hdr);
 
-	if (4 + len != clc_len) {
+	if (srvr->vals->header_preamble_size + len != clc_len) {
 		cifs_dbg(FYI, "Calculated size %u length %u mismatch mid %llu\n",
-			 clc_len, 4 + len, mid);
+			 clc_len, srvr->vals->header_preamble_size + len, 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 - srvr->vals->header_preamble_size == len && 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 == srvr->vals->header_preamble_size + len + 1)
 			return 0;
 
 		/*
@@ -218,10 +219,10 @@ 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 < srvr->vals->header_preamble_size /* RFC1001 header size */ + len) {
 			printk_once(KERN_WARNING
 				"SMB2 server sent bad RFC1001 len %d not %d\n",
-				len, clc_len - 4);
+				len, clc_len - srvr->vals->header_preamble_size);
 			return 0;
 		}
 
diff --git a/fs/cifs/smb2ops.c b/fs/cifs/smb2ops.c
index c5777783f313..968b1d43a1ea 100644
--- a/fs/cifs/smb2ops.c
+++ b/fs/cifs/smb2ops.c
@@ -1457,6 +1457,8 @@ 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);
 
@@ -1479,7 +1481,7 @@ smb2_query_symlink(const unsigned int xid, struct cifs_tcon *tcon,
 	}
 
 	if (le32_to_cpu(err_buf->ByteCount) < sizeof(struct smb2_symlink_err_rsp) ||
-	    get_rfc1002_length(err_buf) + 4 < SMB2_SYMLINK_STRUCT_SIZE) {
+	    get_rfc1002_length(err_buf) + server->vals->header_preamble_size < SMB2_SYMLINK_STRUCT_SIZE) {
 		kfree(utf16_path);
 		return -ENOENT;
 	}
@@ -1492,13 +1494,13 @@ 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 (get_rfc1002_length(err_buf) + server->vals->header_preamble_size <
 			SMB2_SYMLINK_STRUCT_SIZE + sub_offset + sub_len) {
 		kfree(utf16_path);
 		return -ENOENT;
 	}
 
-	if (get_rfc1002_length(err_buf) + 4 <
+	if (get_rfc1002_length(err_buf) + server->vals->header_preamble_size <
 			SMB2_SYMLINK_STRUCT_SIZE + print_offset + print_len) {
 		kfree(utf16_path);
 		return -ENOENT;
@@ -2050,7 +2052,8 @@ 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 TCP_Server_Info *server,
+		   struct smb2_transform_hdr *tr_hdr, struct smb_rqst *old_rq)
 {
 	struct smb2_sync_hdr *shdr =
 			(struct smb2_sync_hdr *)old_rq->rq_iov[1].iov_base;
@@ -2062,7 +2065,7 @@ 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, sizeof(struct smb2_transform_hdr) - server->vals->header_preamble_size);
 	inc_rfc1001_len(tr_hdr, orig_len);
 }
 
@@ -2134,7 +2137,7 @@ 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) - 24;
+	unsigned int assoc_data_len = sizeof(struct smb2_transform_hdr) - 20 - server->vals->header_preamble_size;
 	int rc = 0;
 	struct scatterlist *sg;
 	u8 sign[SMB2_SIGNATURE_SIZE] = {};
@@ -2262,7 +2265,7 @@ smb3_init_transform_rq(struct TCP_Server_Info *server, struct smb_rqst *new_rq,
 		goto err_free_iov;
 
 	/* fill the 1st iov with a transform header */
-	fill_transform_hdr(tr_hdr, old_rq);
+	fill_transform_hdr(server, 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);
 
@@ -2344,10 +2347,10 @@ decrypt_raw_data(struct TCP_Server_Info *server, char *buf,
 	if (rc)
 		return rc;
 
-	memmove(buf + 4, iov[1].iov_base, buf_data_size);
+	memmove(buf + server->vals->header_preamble_size, 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;
+	server->total_read = buf_data_size + page_data_size + server->vals->header_preamble_size;
 
 	return rc;
 }
@@ -2451,7 +2454,7 @@ handle_read_data(struct TCP_Server_Info *server, struct mid_q_entry *mid,
 		return 0;
 	}
 
-	data_offset = server->ops->read_data_offset(buf) + 4;
+	data_offset = server->ops->read_data_offset(buf) + server->vals->header_preamble_size;
 #ifdef CONFIG_CIFS_SMB_DIRECT
 	use_rdma_mr = rdata->mr;
 #endif
@@ -2547,11 +2550,12 @@ 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 = get_rfc1002_length(buf) + server->vals->header_preamble_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 -
+		server->vals->header_preamble_size +
 		sizeof(struct smb2_transform_hdr)) - HEADER_SIZE(server) + 1;
 
 	rc = cifs_read_from_socket(server, buf + HEADER_SIZE(server) - 1, len);
@@ -2559,8 +2563,9 @@ 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 -
-						server->vals->read_rsp_size;
+	len = le32_to_cpu(tr_hdr->OriginalMessageSize) +
+		server->vals->header_preamble_size -
+		server->vals->read_rsp_size;
 	npages = DIV_ROUND_UP(len, PAGE_SIZE);
 
 	pages = kmalloc_array(npages, sizeof(struct page *), GFP_KERNEL);
@@ -2586,7 +2591,8 @@ 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 -
+			      server->vals->header_preamble_size,
 			      pages, npages, len);
 	if (rc)
 		goto free_pages;
@@ -2623,7 +2629,7 @@ 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 + 4 > MAX_CIFS_SMALL_BUFFER_SIZE) {
+	if (pdu_length + server->vals->header_preamble_size > MAX_CIFS_SMALL_BUFFER_SIZE) {
 		server->large_buf = true;
 		memcpy(server->bigbuf, buf, server->total_read);
 		buf = server->bigbuf;
@@ -2631,12 +2637,13 @@ 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 +
+				server->vals->header_preamble_size);
 	if (length < 0)
 		return length;
 	server->total_read += length;
 
-	buf_size = pdu_length + 4 - sizeof(struct smb2_transform_hdr);
+	buf_size = pdu_length + server->vals->header_preamble_size - sizeof(struct smb2_transform_hdr);
 	length = decrypt_raw_data(server, buf, buf_size, NULL, 0, 0);
 	if (length)
 		return length;
@@ -2665,7 +2672,7 @@ 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 + 4 < sizeof(struct smb2_transform_hdr) +
+	if (pdu_length + server->vals->header_preamble_size < sizeof(struct smb2_transform_hdr) +
 						sizeof(struct smb2_sync_hdr)) {
 		cifs_dbg(VFS, "Transform message is too small (%u)\n",
 			 pdu_length);
@@ -2674,14 +2681,14 @@ 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 + server->vals->header_preamble_size < 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 + server->vals->header_preamble_size > CIFSMaxBufSize + MAX_HEADER_SIZE(server))
 		return receive_encrypted_read(server, mid);
 
 	return receive_encrypted_standard(server, mid);
@@ -2692,7 +2699,8 @@ 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, get_rfc1002_length(buf) + 4,
+	return handle_read_data(server, mid, buf, get_rfc1002_length(buf) +
+				server->vals->header_preamble_size,
 				NULL, 0, 0);
 }
 
@@ -3097,6 +3105,7 @@ struct smb_version_values smb20_values = {
 	.shared_lock_type = SMB2_LOCKFLAG_SHARED_LOCK,
 	.unlock_lock_type = SMB2_LOCKFLAG_UNLOCK,
 	.header_size = sizeof(struct smb2_hdr),
+	.header_preamble_size = 4,
 	.max_header_size = MAX_SMB2_HDR_SIZE,
 	.read_rsp_size = sizeof(struct smb2_read_rsp) - 1,
 	.lock_cmd = SMB2_LOCK,
@@ -3117,6 +3126,7 @@ struct smb_version_values smb21_values = {
 	.shared_lock_type = SMB2_LOCKFLAG_SHARED_LOCK,
 	.unlock_lock_type = SMB2_LOCKFLAG_UNLOCK,
 	.header_size = sizeof(struct smb2_hdr),
+	.header_preamble_size = 4,
 	.max_header_size = MAX_SMB2_HDR_SIZE,
 	.read_rsp_size = sizeof(struct smb2_read_rsp) - 1,
 	.lock_cmd = SMB2_LOCK,
@@ -3137,6 +3147,7 @@ struct smb_version_values smb3any_values = {
 	.shared_lock_type = SMB2_LOCKFLAG_SHARED_LOCK,
 	.unlock_lock_type = SMB2_LOCKFLAG_UNLOCK,
 	.header_size = sizeof(struct smb2_hdr),
+	.header_preamble_size = 4,
 	.max_header_size = MAX_SMB2_HDR_SIZE,
 	.read_rsp_size = sizeof(struct smb2_read_rsp) - 1,
 	.lock_cmd = SMB2_LOCK,
@@ -3157,6 +3168,7 @@ struct smb_version_values smbdefault_values = {
 	.shared_lock_type = SMB2_LOCKFLAG_SHARED_LOCK,
 	.unlock_lock_type = SMB2_LOCKFLAG_UNLOCK,
 	.header_size = sizeof(struct smb2_hdr),
+	.header_preamble_size = 4,
 	.max_header_size = MAX_SMB2_HDR_SIZE,
 	.read_rsp_size = sizeof(struct smb2_read_rsp) - 1,
 	.lock_cmd = SMB2_LOCK,
@@ -3177,6 +3189,7 @@ struct smb_version_values smb30_values = {
 	.shared_lock_type = SMB2_LOCKFLAG_SHARED_LOCK,
 	.unlock_lock_type = SMB2_LOCKFLAG_UNLOCK,
 	.header_size = sizeof(struct smb2_hdr),
+	.header_preamble_size = 4,
 	.max_header_size = MAX_SMB2_HDR_SIZE,
 	.read_rsp_size = sizeof(struct smb2_read_rsp) - 1,
 	.lock_cmd = SMB2_LOCK,
@@ -3197,6 +3210,7 @@ struct smb_version_values smb302_values = {
 	.shared_lock_type = SMB2_LOCKFLAG_SHARED_LOCK,
 	.unlock_lock_type = SMB2_LOCKFLAG_UNLOCK,
 	.header_size = sizeof(struct smb2_hdr),
+	.header_preamble_size = 4,
 	.max_header_size = MAX_SMB2_HDR_SIZE,
 	.read_rsp_size = sizeof(struct smb2_read_rsp) - 1,
 	.lock_cmd = SMB2_LOCK,
@@ -3218,6 +3232,7 @@ struct smb_version_values smb311_values = {
 	.shared_lock_type = SMB2_LOCKFLAG_SHARED_LOCK,
 	.unlock_lock_type = SMB2_LOCKFLAG_UNLOCK,
 	.header_size = sizeof(struct smb2_hdr),
+	.header_preamble_size = 4,
 	.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 af62c75b17c4..0e04b577758d 100644
--- a/fs/cifs/smb2pdu.c
+++ b/fs/cifs/smb2pdu.c
@@ -1471,7 +1471,7 @@ 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 + server->vals->header_preamble_size + le32_to_cpu(rsp->CreateContextsOffset);
 	remaining = le32_to_cpu(rsp->CreateContextsLength);
 	cc = (struct create_context *)data_offset;
 	while (remaining >= sizeof(struct create_context)) {
@@ -3452,6 +3452,7 @@ static int
 build_qfs_info_req(struct kvec *iov, struct cifs_tcon *tcon, int level,
 		   int outbuf_len, u64 persistent_fid, u64 volatile_fid)
 {
+	struct TCP_Server_Info *server = tcon->ses->server;
 	int rc;
 	struct smb2_query_info_req *req;
 	unsigned int total_len;
@@ -3474,7 +3475,7 @@ 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 - server->vals->header_preamble_size);
 
 	iov->iov_base = (char *)req;
 	iov->iov_len = total_len;
@@ -3491,6 +3492,7 @@ 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;
 
@@ -3511,7 +3513,7 @@ 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 */ +
+	info = (struct smb2_fs_full_size_info *)(server->vals->header_preamble_size +
 		le16_to_cpu(rsp->OutputBufferOffset) + (char *)&rsp->hdr);
 	rc = validate_buf(le16_to_cpu(rsp->OutputBufferOffset),
 			  le32_to_cpu(rsp->OutputBufferLength), &rsp->hdr,
@@ -3534,6 +3536,7 @@ 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;
 
@@ -3574,15 +3577,15 @@ SMB2_QFS_attr(const unsigned int xid, struct cifs_tcon *tcon,
 		goto qfsattr_exit;
 
 	if (level == FS_ATTRIBUTE_INFORMATION)
-		memcpy(&tcon->fsAttrInfo, 4 /* RFC1001 len */ + offset
+		memcpy(&tcon->fsAttrInfo, server->vals->header_preamble_size + offset
 			+ (char *)&rsp->hdr, min_t(unsigned int,
 			rsp_len, max_len));
 	else if (level == FS_DEVICE_INFORMATION)
-		memcpy(&tcon->fsDevInfo, 4 /* RFC1001 len */ + offset
+		memcpy(&tcon->fsDevInfo, server->vals->header_preamble_size + offset
 			+ (char *)&rsp->hdr, 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);
+			(server->vals->header_preamble_size + offset + (char *)&rsp->hdr);
 		tcon->ss_flags = le32_to_cpu(ss_info->Flags);
 		tcon->perf_sector_size =
 			le32_to_cpu(ss_info->PhysicalBytesPerSectorForPerf);
diff --git a/fs/cifs/transport.c b/fs/cifs/transport.c
index 665661464067..279718dcb2ed 100644
--- a/fs/cifs/transport.c
+++ b/fs/cifs/transport.c
@@ -790,7 +790,8 @@ 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 = get_rfc1002_length(buf) +
+		ses->server->vals->header_preamble_size;
 	if (midQ->large_buf)
 		*resp_buf_type = CIFS_LARGE_BUFFER;
 	else

From 6c4ba31133f1af68fd9abe070debeec14e7307d8 Mon Sep 17 00:00:00 2001
From: Steve French <stfrench@microsoft.com>
Date: Sat, 31 Mar 2018 12:36:26 -0500
Subject: [PATCH 18/20] cifs: fix sparse warning on previous patch in a few
 printks

Signed-off-by: Steve French <smfrench@gmail.com>
CC: Ronnie Sahlberg <lsahlber@redhat.com>
---
 fs/cifs/smb2misc.c | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/fs/cifs/smb2misc.c b/fs/cifs/smb2misc.c
index dfa5d9f4e00b..5406e95f5d92 100644
--- a/fs/cifs/smb2misc.c
+++ b/fs/cifs/smb2misc.c
@@ -191,7 +191,7 @@ smb2_check_message(char *buf, unsigned int length, struct TCP_Server_Info *srvr)
 	}
 
 	if (srvr->vals->header_preamble_size + len != length) {
-		cifs_dbg(VFS, "Total length %u RFC1002 length %u mismatch mid %llu\n",
+		cifs_dbg(VFS, "Total length %u RFC1002 length %zu mismatch mid %llu\n",
 			 length, srvr->vals->header_preamble_size + len, mid);
 		return 1;
 	}
@@ -199,7 +199,7 @@ smb2_check_message(char *buf, unsigned int length, struct TCP_Server_Info *srvr)
 	clc_len = smb2_calc_size(hdr);
 
 	if (srvr->vals->header_preamble_size + len != clc_len) {
-		cifs_dbg(FYI, "Calculated size %u length %u mismatch mid %llu\n",
+		cifs_dbg(FYI, "Calculated size %u length %zu mismatch mid %llu\n",
 			 clc_len, srvr->vals->header_preamble_size + len, mid);
 		/* create failed on symlink */
 		if (command == SMB2_CREATE_HE &&
@@ -221,7 +221,7 @@ smb2_check_message(char *buf, unsigned int length, struct TCP_Server_Info *srvr)
 		 */
 		if (clc_len < srvr->vals->header_preamble_size /* RFC1001 header size */ + len) {
 			printk_once(KERN_WARNING
-				"SMB2 server sent bad RFC1001 len %d not %d\n",
+				"SMB2 server sent bad RFC1001 len %d not %zu\n",
 				len, clc_len - srvr->vals->header_preamble_size);
 			return 0;
 		}

From 7ea884c77e5c97f1e0a1a422d961d27f78ca2745 Mon Sep 17 00:00:00 2001
From: Steve French <stfrench@microsoft.com>
Date: Sat, 31 Mar 2018 18:13:38 -0500
Subject: [PATCH 19/20] smb3: Fix root directory when server returns inode
 number of zero

Some servers return inode number zero for the root directory, which
causes ls to display incorrect data (missing "." and "..").

If the server returns zero for the inode number of the root directory,
fake an inode number for it.

Signed-off-by: Steve French <smfrench@gmail.com>
Reviewed-by: Pavel Shilovsky <pshilov@microsoft.com>
CC: Stable <stable@vger.kernel.org>
---
 fs/cifs/cifsglob.h |  1 +
 fs/cifs/inode.c    | 33 +++++++++++++++++++++++++++++++++
 2 files changed, 34 insertions(+)

diff --git a/fs/cifs/cifsglob.h b/fs/cifs/cifsglob.h
index 3e3f86841372..2282562e78a1 100644
--- a/fs/cifs/cifsglob.h
+++ b/fs/cifs/cifsglob.h
@@ -1470,6 +1470,7 @@ struct dfs_info3_param {
 #define CIFS_FATTR_NEED_REVAL		0x4
 #define CIFS_FATTR_INO_COLLISION	0x8
 #define CIFS_FATTR_UNKNOWN_NLINK	0x10
+#define CIFS_FATTR_FAKE_ROOT_INO	0x20
 
 struct cifs_fattr {
 	u32		cf_flags;
diff --git a/fs/cifs/inode.c b/fs/cifs/inode.c
index c98a852180b1..f856df4adae3 100644
--- a/fs/cifs/inode.c
+++ b/fs/cifs/inode.c
@@ -707,6 +707,18 @@ cgfi_exit:
 	return rc;
 }
 
+/* Simple function to return a 64 bit hash of string.  Rarely called */
+static __u64 simple_hashstr(const char *str)
+{
+	const __u64 hash_mult =  1125899906842597L; /* a big enough prime */
+	__u64 hash = 0;
+
+	while (*str)
+		hash = (hash + (__u64) *str++) * hash_mult;
+
+	return hash;
+}
+
 int
 cifs_get_inode_info(struct inode **inode, const char *full_path,
 		    FILE_ALL_INFO *data, struct super_block *sb, int xid,
@@ -816,6 +828,14 @@ cifs_get_inode_info(struct inode **inode, const char *full_path,
 						 tmprc);
 					fattr.cf_uniqueid = iunique(sb, ROOT_I);
 					cifs_autodisable_serverino(cifs_sb);
+				} else if ((fattr.cf_uniqueid == 0) &&
+						strlen(full_path) == 0) {
+					/* some servers ret bad root ino ie 0 */
+					cifs_dbg(FYI, "Invalid (0) inodenum\n");
+					fattr.cf_flags |=
+						CIFS_FATTR_FAKE_ROOT_INO;
+					fattr.cf_uniqueid =
+						simple_hashstr(tcon->treeName);
 				}
 			}
 		} else
@@ -832,6 +852,16 @@ cifs_get_inode_info(struct inode **inode, const char *full_path,
 				&fattr.cf_uniqueid, data);
 			if (tmprc)
 				fattr.cf_uniqueid = CIFS_I(*inode)->uniqueid;
+			else if ((fattr.cf_uniqueid == 0) &&
+					strlen(full_path) == 0) {
+				/*
+				 * Reuse existing root inode num since
+				 * inum zero for root causes ls of . and .. to
+				 * not be returned
+				 */
+				cifs_dbg(FYI, "Srv ret 0 inode num for root\n");
+				fattr.cf_uniqueid = CIFS_I(*inode)->uniqueid;
+			}
 		} else
 			fattr.cf_uniqueid = CIFS_I(*inode)->uniqueid;
 	}
@@ -893,6 +923,9 @@ cifs_get_inode_info(struct inode **inode, const char *full_path,
 	}
 
 cgii_exit:
+	if ((*inode) && ((*inode)->i_ino == 0))
+		cifs_dbg(FYI, "inode number of zero returned\n");
+
 	kfree(buf);
 	cifs_put_tlink(tlink);
 	return rc;

From 07108d0e7c7fbbf9c6d76c0af2f1813e4f3f0800 Mon Sep 17 00:00:00 2001
From: Steve French <stfrench@microsoft.com>
Date: Sun, 1 Apr 2018 20:15:55 -0500
Subject: [PATCH 20/20] cifs: Add minor debug message during negprot

Check for unknown security mode flags during negotiate protocol
if debugging enabled.

Signed-off-by: Steve French <smfrench@gmail.com>
Reviewed-by: Pavel Shilovsky <pshilov@microsoft.com>
---
 fs/cifs/smb2pdu.c | 4 +++-
 fs/cifs/smb2pdu.h | 2 ++
 2 files changed, 5 insertions(+), 1 deletion(-)

diff --git a/fs/cifs/smb2pdu.c b/fs/cifs/smb2pdu.c
index 0e04b577758d..f7741cee2a4c 100644
--- a/fs/cifs/smb2pdu.c
+++ b/fs/cifs/smb2pdu.c
@@ -584,8 +584,10 @@ SMB2_negotiate(const unsigned int xid, struct cifs_ses *ses)
 			       SMB2_MAX_BUFFER_SIZE);
 	server->max_read = le32_to_cpu(rsp->MaxReadSize);
 	server->max_write = le32_to_cpu(rsp->MaxWriteSize);
-	/* BB Do we need to validate the SecurityMode? */
 	server->sec_mode = le16_to_cpu(rsp->SecurityMode);
+	if ((server->sec_mode & SMB2_SEC_MODE_FLAGS_ALL) != server->sec_mode)
+		cifs_dbg(FYI, "Server returned unexpected security mode 0x%x\n",
+				server->sec_mode);
 	server->capabilities = le32_to_cpu(rsp->Capabilities);
 	/* Internal types */
 	server->capabilities |= SMB2_NT_FIND | SMB2_LARGE_FILES;
diff --git a/fs/cifs/smb2pdu.h b/fs/cifs/smb2pdu.h
index 8b901c69a65a..253e2c7c952f 100644
--- a/fs/cifs/smb2pdu.h
+++ b/fs/cifs/smb2pdu.h
@@ -249,6 +249,8 @@ struct smb2_negotiate_req {
 /* SecurityMode flags */
 #define	SMB2_NEGOTIATE_SIGNING_ENABLED	0x0001
 #define SMB2_NEGOTIATE_SIGNING_REQUIRED	0x0002
+#define SMB2_SEC_MODE_FLAGS_ALL		0x0003
+
 /* Capabilities flags */
 #define SMB2_GLOBAL_CAP_DFS		0x00000001
 #define SMB2_GLOBAL_CAP_LEASING		0x00000002 /* Resp only New to SMB2.1 */