1 files changed, 406 insertions, 148 deletions

diff --git a/fs/cifs/sess.c b/fs/cifs/sess.c
index 035dc3e245dc..92e4278ec35d 100644
--- a/fs/cifs/sess.c
+++ b/fs/cifs/sess.c
@@ -17,6 +17,8 @@
 #include "nterr.h"
 #include <linux/utsname.h>
 #include <linux/slab.h>
+#include <linux/version.h>
+#include "cifsfs.h"
 #include "cifs_spnego.h"
 #include "smb2proto.h"
 #include "fs_context.h"
@@ -56,7 +58,7 @@ bool is_ses_using_iface(struct cifs_ses *ses, struct cifs_server_iface *iface)
 
 	spin_lock(&ses->chan_lock);
 	for (i = 0; i < ses->chan_count; i++) {
-		if (is_server_using_iface(ses->chans[i].server, iface)) {
+		if (ses->chans[i].iface == iface) {
 			spin_unlock(&ses->chan_lock);
 			return true;
 		}
@@ -65,21 +67,103 @@ bool is_ses_using_iface(struct cifs_ses *ses, struct cifs_server_iface *iface)
 	return false;
 }
 
+/* channel helper functions. assumed that chan_lock is held by caller. */
+
+unsigned int
+cifs_ses_get_chan_index(struct cifs_ses *ses,
+			struct TCP_Server_Info *server)
+{
+	unsigned int i;
+
+	for (i = 0; i < ses->chan_count; i++) {
+		if (ses->chans[i].server == server)
+			return i;
+	}
+
+	/* If we didn't find the channel, it is likely a bug */
+	if (server)
+		cifs_dbg(VFS, "unable to get chan index for server: 0x%llx",
+			 server->conn_id);
+	WARN_ON(1);
+	return 0;
+}
+
+void
+cifs_chan_set_in_reconnect(struct cifs_ses *ses,
+			     struct TCP_Server_Info *server)
+{
+	unsigned int chan_index = cifs_ses_get_chan_index(ses, server);
+
+	ses->chans[chan_index].in_reconnect = true;
+}
+
+void
+cifs_chan_clear_in_reconnect(struct cifs_ses *ses,
+			     struct TCP_Server_Info *server)
+{
+	unsigned int chan_index = cifs_ses_get_chan_index(ses, server);
+
+	ses->chans[chan_index].in_reconnect = false;
+}
+
+bool
+cifs_chan_in_reconnect(struct cifs_ses *ses,
+			  struct TCP_Server_Info *server)
+{
+	unsigned int chan_index = cifs_ses_get_chan_index(ses, server);
+
+	return CIFS_CHAN_IN_RECONNECT(ses, chan_index);
+}
+
+void
+cifs_chan_set_need_reconnect(struct cifs_ses *ses,
+			     struct TCP_Server_Info *server)
+{
+	unsigned int chan_index = cifs_ses_get_chan_index(ses, server);
+
+	set_bit(chan_index, &ses->chans_need_reconnect);
+	cifs_dbg(FYI, "Set reconnect bitmask for chan %u; now 0x%lx\n",
+		 chan_index, ses->chans_need_reconnect);
+}
+
+void
+cifs_chan_clear_need_reconnect(struct cifs_ses *ses,
+			       struct TCP_Server_Info *server)
+{
+	unsigned int chan_index = cifs_ses_get_chan_index(ses, server);
+
+	clear_bit(chan_index, &ses->chans_need_reconnect);
+	cifs_dbg(FYI, "Cleared reconnect bitmask for chan %u; now 0x%lx\n",
+		 chan_index, ses->chans_need_reconnect);
+}
+
+bool
+cifs_chan_needs_reconnect(struct cifs_ses *ses,
+			  struct TCP_Server_Info *server)
+{
+	unsigned int chan_index = cifs_ses_get_chan_index(ses, server);
+
+	return CIFS_CHAN_NEEDS_RECONNECT(ses, chan_index);
+}
+
+bool
+cifs_chan_is_iface_active(struct cifs_ses *ses,
+			  struct TCP_Server_Info *server)
+{
+	unsigned int chan_index = cifs_ses_get_chan_index(ses, server);
+
+	return ses->chans[chan_index].iface &&
+		ses->chans[chan_index].iface->is_active;
+}
+
 /* returns number of channels added */
 int cifs_try_adding_channels(struct cifs_sb_info *cifs_sb, struct cifs_ses *ses)
 {
 	int old_chan_count, new_chan_count;
 	int left;
-	int i = 0;
 	int rc = 0;
 	int tries = 0;
-	struct cifs_server_iface *ifaces = NULL;
-	size_t iface_count;
-
-	if (ses->server->dialect < SMB30_PROT_ID) {
-		cifs_dbg(VFS, "multichannel is not supported on this protocol version, use 3.0 or above\n");
-		return 0;
-	}
+	struct cifs_server_iface *iface = NULL, *niface = NULL;
 
 	spin_lock(&ses->chan_lock);
 
@@ -87,10 +171,16 @@ int cifs_try_adding_channels(struct cifs_sb_info *cifs_sb, struct cifs_ses *ses)
 	left = ses->chan_max - ses->chan_count;
 
 	if (left <= 0) {
+		spin_unlock(&ses->chan_lock);
 		cifs_dbg(FYI,
 			 "ses already at max_channels (%zu), nothing to open\n",
 			 ses->chan_max);
+		return 0;
+	}
+
+	if (ses->server->dialect < SMB30_PROT_ID) {
 		spin_unlock(&ses->chan_lock);
+		cifs_dbg(VFS, "multichannel is not supported on this protocol version, use 3.0 or above\n");
 		return 0;
 	}
 
@@ -103,32 +193,16 @@ int cifs_try_adding_channels(struct cifs_sb_info *cifs_sb, struct cifs_ses *ses)
 	spin_unlock(&ses->chan_lock);
 
 	/*
-	 * Make a copy of the iface list at the time and use that
-	 * instead so as to not hold the iface spinlock for opening
-	 * channels
-	 */
-	spin_lock(&ses->iface_lock);
-	iface_count = ses->iface_count;
-	if (iface_count <= 0) {
-		spin_unlock(&ses->iface_lock);
-		cifs_dbg(VFS, "no iface list available to open channels\n");
-		return 0;
-	}
-	ifaces = kmemdup(ses->iface_list, iface_count*sizeof(*ifaces),
-			 GFP_ATOMIC);
-	if (!ifaces) {
-		spin_unlock(&ses->iface_lock);
-		return 0;
-	}
-	spin_unlock(&ses->iface_lock);
-
-	/*
 	 * Keep connecting to same, fastest, iface for all channels as
 	 * long as its RSS. Try next fastest one if not RSS or channel
 	 * creation fails.
 	 */
+	spin_lock(&ses->iface_lock);
+	iface = list_first_entry(&ses->iface_list, struct cifs_server_iface,
+				 iface_head);
+	spin_unlock(&ses->iface_lock);
+
 	while (left > 0) {
-		struct cifs_server_iface *iface;
 
 		tries++;
 		if (tries > 3*ses->chan_max) {
@@ -137,31 +211,128 @@ int cifs_try_adding_channels(struct cifs_sb_info *cifs_sb, struct cifs_ses *ses)
 			break;
 		}
 
-		iface = &ifaces[i];
-		if (is_ses_using_iface(ses, iface) && !iface->rss_capable) {
-			i = (i+1) % iface_count;
-			continue;
+		spin_lock(&ses->iface_lock);
+		if (!ses->iface_count) {
+			spin_unlock(&ses->iface_lock);
+			break;
 		}
 
-		rc = cifs_ses_add_channel(cifs_sb, ses, iface);
-		if (rc) {
-			cifs_dbg(FYI, "failed to open extra channel on iface#%d rc=%d\n",
-				 i, rc);
-			i = (i+1) % iface_count;
-			continue;
+		list_for_each_entry_safe_from(iface, niface, &ses->iface_list,
+				    iface_head) {
+			/* skip ifaces that are unusable */
+			if (!iface->is_active ||
+			    (is_ses_using_iface(ses, iface) &&
+			     !iface->rss_capable)) {
+				continue;
+			}
+
+			/* take ref before unlock */
+			kref_get(&iface->refcount);
+
+			spin_unlock(&ses->iface_lock);
+			rc = cifs_ses_add_channel(cifs_sb, ses, iface);
+			spin_lock(&ses->iface_lock);
+
+			if (rc) {
+				cifs_dbg(VFS, "failed to open extra channel on iface:%pIS rc=%d\n",
+					 &iface->sockaddr,
+					 rc);
+				kref_put(&iface->refcount, release_iface);
+				continue;
+			}
+
+			cifs_dbg(FYI, "successfully opened new channel on iface:%pIS\n",
+				 &iface->sockaddr);
+			break;
 		}
+		spin_unlock(&ses->iface_lock);
 
-		cifs_dbg(FYI, "successfully opened new channel on iface#%d\n",
-			 i);
 		left--;
 		new_chan_count++;
 	}
 
-	kfree(ifaces);
 	return new_chan_count - old_chan_count;
 }
 
 /*
+ * update the iface for the channel if necessary.
+ * will return 0 when iface is updated, 1 if removed, 2 otherwise
+ * Must be called with chan_lock held.
+ */
+int
+cifs_chan_update_iface(struct cifs_ses *ses, struct TCP_Server_Info *server)
+{
+	unsigned int chan_index;
+	struct cifs_server_iface *iface = NULL;
+	struct cifs_server_iface *old_iface = NULL;
+	int rc = 0;
+
+	spin_lock(&ses->chan_lock);
+	chan_index = cifs_ses_get_chan_index(ses, server);
+	if (!chan_index) {
+		spin_unlock(&ses->chan_lock);
+		return 0;
+	}
+
+	if (ses->chans[chan_index].iface) {
+		old_iface = ses->chans[chan_index].iface;
+		if (old_iface->is_active) {
+			spin_unlock(&ses->chan_lock);
+			return 1;
+		}
+	}
+	spin_unlock(&ses->chan_lock);
+
+	spin_lock(&ses->iface_lock);
+	/* then look for a new one */
+	list_for_each_entry(iface, &ses->iface_list, iface_head) {
+		if (!iface->is_active ||
+		    (is_ses_using_iface(ses, iface) &&
+		     !iface->rss_capable)) {
+			continue;
+		}
+		kref_get(&iface->refcount);
+	}
+
+	if (!list_entry_is_head(iface, &ses->iface_list, iface_head)) {
+		rc = 1;
+		iface = NULL;
+		cifs_dbg(FYI, "unable to find a suitable iface\n");
+	}
+
+	/* now drop the ref to the current iface */
+	if (old_iface && iface) {
+		kref_put(&old_iface->refcount, release_iface);
+		cifs_dbg(FYI, "replacing iface: %pIS with %pIS\n",
+			 &old_iface->sockaddr,
+			 &iface->sockaddr);
+	} else if (old_iface) {
+		kref_put(&old_iface->refcount, release_iface);
+		cifs_dbg(FYI, "releasing ref to iface: %pIS\n",
+			 &old_iface->sockaddr);
+	} else {
+		WARN_ON(!iface);
+		cifs_dbg(FYI, "adding new iface: %pIS\n", &iface->sockaddr);
+	}
+	spin_unlock(&ses->iface_lock);
+
+	spin_lock(&ses->chan_lock);
+	chan_index = cifs_ses_get_chan_index(ses, server);
+	ses->chans[chan_index].iface = iface;
+
+	/* No iface is found. if secondary chan, drop connection */
+	if (!iface && CIFS_SERVER_IS_CHAN(server))
+		ses->chans[chan_index].server = NULL;
+
+	spin_unlock(&ses->chan_lock);
+
+	if (!iface && CIFS_SERVER_IS_CHAN(server))
+		cifs_put_tcp_session(server, false);
+
+	return rc;
+}
+
+/*
  * If server is a channel of ses, return the corresponding enclosing
  * cifs_chan otherwise return NULL.
  */
@@ -222,7 +393,10 @@ cifs_ses_add_channel(struct cifs_sb_info *cifs_sb, struct cifs_ses *ses,
 	/* Auth */
 	ctx.domainauto = ses->domainAuto;
 	ctx.domainname = ses->domainName;
-	ctx.server_hostname = ses->server->hostname;
+
+	/* no hostname for extra channels */
+	ctx.server_hostname = "";
+
 	ctx.username = ses->user_name;
 	ctx.password = ses->password;
 	ctx.sectype = ses->sectype;
@@ -261,9 +435,8 @@ cifs_ses_add_channel(struct cifs_sb_info *cifs_sb, struct cifs_ses *ses,
 
 	chan_server = cifs_get_tcp_session(&ctx, ses->server);
 
-	mutex_lock(&ses->session_mutex);
 	spin_lock(&ses->chan_lock);
-	chan = ses->binding_chan = &ses->chans[ses->chan_count];
+	chan = &ses->chans[ses->chan_count];
 	chan->server = chan_server;
 	if (IS_ERR(chan->server)) {
 		rc = PTR_ERR(chan->server);
@@ -271,8 +444,16 @@ cifs_ses_add_channel(struct cifs_sb_info *cifs_sb, struct cifs_ses *ses,
 		spin_unlock(&ses->chan_lock);
 		goto out;
 	}
+	chan->iface = iface;
+	ses->chan_count++;
+	atomic_set(&ses->chan_seq, 0);
+
+	/* Mark this channel as needing connect/setup */
+	cifs_chan_set_need_reconnect(ses, chan->server);
+
 	spin_unlock(&ses->chan_lock);
 
+	mutex_lock(&ses->session_mutex);
 	/*
 	 * We need to allocate the server crypto now as we will need
 	 * to sign packets before we generate the channel signing key
@@ -281,58 +462,48 @@ cifs_ses_add_channel(struct cifs_sb_info *cifs_sb, struct cifs_ses *ses,
 	rc = smb311_crypto_shash_allocate(chan->server);
 	if (rc) {
 		cifs_dbg(VFS, "%s: crypto alloc failed\n", __func__);
+		mutex_unlock(&ses->session_mutex);
 		goto out;
 	}
 
-	ses->binding = true;
-	rc = cifs_negotiate_protocol(xid, ses);
-	if (rc)
-		goto out;
+	rc = cifs_negotiate_protocol(xid, ses, chan->server);
+	if (!rc)
+		rc = cifs_setup_session(xid, ses, chan->server, cifs_sb->local_nls);
 
-	rc = cifs_setup_session(xid, ses, cifs_sb->local_nls);
-	if (rc)
-		goto out;
-
-	/* success, put it on the list
-	 * XXX: sharing ses between 2 tcp servers is not possible, the
-	 * way "internal" linked lists works in linux makes element
-	 * only able to belong to one list
-	 *
-	 * the binding session is already established so the rest of
-	 * the code should be able to look it up, no need to add the
-	 * ses to the new server.
-	 */
-
-	spin_lock(&ses->chan_lock);
-	ses->chan_count++;
-	atomic_set(&ses->chan_seq, 0);
-	spin_unlock(&ses->chan_lock);
+	mutex_unlock(&ses->session_mutex);
 
 out:
-	ses->binding = false;
-	ses->binding_chan = NULL;
-	mutex_unlock(&ses->session_mutex);
+	if (rc && chan->server) {
+		/*
+		 * we should avoid race with these delayed works before we
+		 * remove this channel
+		 */
+		cancel_delayed_work_sync(&chan->server->echo);
+		cancel_delayed_work_sync(&chan->server->resolve);
+		cancel_delayed_work_sync(&chan->server->reconnect);
+
+		spin_lock(&ses->chan_lock);
+		/* we rely on all bits beyond chan_count to be clear */
+		cifs_chan_clear_need_reconnect(ses, chan->server);
+		ses->chan_count--;
+		/*
+		 * chan_count should never reach 0 as at least the primary
+		 * channel is always allocated
+		 */
+		WARN_ON(ses->chan_count < 1);
+		spin_unlock(&ses->chan_lock);
 
-	if (rc && chan->server)
 		cifs_put_tcp_session(chan->server, 0);
+	}
 
+	free_xid(xid);
 	return rc;
 }
 
-/* Mark all session channels for reconnect */
-void cifs_ses_mark_for_reconnect(struct cifs_ses *ses)
-{
-	int i;
-
-	for (i = 0; i < ses->chan_count; i++) {
-		spin_lock(&GlobalMid_Lock);
-		if (ses->chans[i].server->tcpStatus != CifsExiting)
-			ses->chans[i].server->tcpStatus = CifsNeedReconnect;
-		spin_unlock(&GlobalMid_Lock);
-	}
-}
-
-static __u32 cifs_ssetup_hdr(struct cifs_ses *ses, SESSION_SETUP_ANDX *pSMB)
+#ifdef CONFIG_CIFS_ALLOW_INSECURE_LEGACY
+static __u32 cifs_ssetup_hdr(struct cifs_ses *ses,
+			     struct TCP_Server_Info *server,
+			     SESSION_SETUP_ANDX *pSMB)
 {
 	__u32 capabilities = 0;
 
@@ -345,7 +516,7 @@ static __u32 cifs_ssetup_hdr(struct cifs_ses *ses, SESSION_SETUP_ANDX *pSMB)
 	pSMB->req.MaxBufferSize = cpu_to_le16(min_t(u32,
 					CIFSMaxBufSize + MAX_CIFS_HDR_SIZE - 4,
 					USHRT_MAX));
-	pSMB->req.MaxMpxCount = cpu_to_le16(ses->server->maxReq);
+	pSMB->req.MaxMpxCount = cpu_to_le16(server->maxReq);
 	pSMB->req.VcNumber = cpu_to_le16(1);
 
 	/* Now no need to set SMBFLG_CASELESS or obsolete CANONICAL PATH */
@@ -356,7 +527,7 @@ static __u32 cifs_ssetup_hdr(struct cifs_ses *ses, SESSION_SETUP_ANDX *pSMB)
 	capabilities = CAP_LARGE_FILES | CAP_NT_SMBS | CAP_LEVEL_II_OPLOCKS |
 			CAP_LARGE_WRITE_X | CAP_LARGE_READ_X;
 
-	if (ses->server->sign)
+	if (server->sign)
 		pSMB->req.hdr.Flags2 |= SMBFLG2_SECURITY_SIGNATURE;
 
 	if (ses->capabilities & CAP_UNICODE) {
@@ -422,7 +593,6 @@ static void unicode_domain_string(char **pbcc_area, struct cifs_ses *ses,
 	*pbcc_area = bcc_ptr;
 }
 
-
 static void unicode_ssetup_strings(char **pbcc_area, struct cifs_ses *ses,
 				   const struct nls_table *nls_cp)
 {
@@ -432,11 +602,6 @@ static void unicode_ssetup_strings(char **pbcc_area, struct cifs_ses *ses,
 	/* BB FIXME add check that strings total less
 	than 335 or will need to send them as arrays */
 
-	/* unicode strings, must be word aligned before the call */
-/*	if ((long) bcc_ptr % 2)	{
-		*bcc_ptr = 0;
-		bcc_ptr++;
-	} */
 	/* copy user */
 	if (ses->user_name == NULL) {
 		/* null user mount */
@@ -584,6 +749,7 @@ static void decode_ascii_ssetup(char **pbcc_area, __u16 bleft,
 	   for it later, but it is not very important */
 	cifs_dbg(FYI, "ascii: bytes left %d\n", bleft);
 }
+#endif /* CONFIG_CIFS_ALLOW_INSECURE_LEGACY */
 
 int decode_ntlmssp_challenge(char *bcc_ptr, int blob_len,
 				    struct cifs_ses *ses)
@@ -675,7 +841,11 @@ static int size_of_ntlmssp_blob(struct cifs_ses *ses, int base_size)
 	else
 		sz += sizeof(__le16);
 
-	sz += sizeof(__le16) * strnlen(ses->workstation_name, CIFS_MAX_WORKSTATION_LEN);
+	if (ses->workstation_name[0])
+		sz += sizeof(__le16) * strnlen(ses->workstation_name,
+					       ntlmssp_workstation_name_size(ses));
+	else
+		sz += sizeof(__le16);
 
 	return sz;
 }
@@ -719,10 +889,10 @@ static inline void cifs_security_buffer_from_str(SECURITY_BUFFER *pbuf,
 int build_ntlmssp_negotiate_blob(unsigned char **pbuffer,
 				 u16 *buflen,
 				 struct cifs_ses *ses,
+				 struct TCP_Server_Info *server,
 				 const struct nls_table *nls_cp)
 {
 	int rc = 0;
-	struct TCP_Server_Info *server = cifs_ses_server(ses);
 	NEGOTIATE_MESSAGE *sec_blob;
 	__u32 flags;
 	unsigned char *tmp;
@@ -773,9 +943,78 @@ setup_ntlm_neg_ret:
 	return rc;
 }
 
+/*
+ * Build ntlmssp blob with additional fields, such as version,
+ * supported by modern servers. For safety limit to SMB3 or later
+ * See notes in MS-NLMP Section 2.2.2.1 e.g.
+ */
+int build_ntlmssp_smb3_negotiate_blob(unsigned char **pbuffer,
+				 u16 *buflen,
+				 struct cifs_ses *ses,
+				 struct TCP_Server_Info *server,
+				 const struct nls_table *nls_cp)
+{
+	int rc = 0;
+	struct negotiate_message *sec_blob;
+	__u32 flags;
+	unsigned char *tmp;
+	int len;
+
+	len = size_of_ntlmssp_blob(ses, sizeof(struct negotiate_message));
+	*pbuffer = kmalloc(len, GFP_KERNEL);
+	if (!*pbuffer) {
+		rc = -ENOMEM;
+		cifs_dbg(VFS, "Error %d during NTLMSSP allocation\n", rc);
+		*buflen = 0;
+		goto setup_ntlm_smb3_neg_ret;
+	}
+	sec_blob = (struct negotiate_message *)*pbuffer;
+
+	memset(*pbuffer, 0, sizeof(struct negotiate_message));
+	memcpy(sec_blob->Signature, NTLMSSP_SIGNATURE, 8);
+	sec_blob->MessageType = NtLmNegotiate;
+
+	/* BB is NTLMV2 session security format easier to use here? */
+	flags = NTLMSSP_NEGOTIATE_56 |	NTLMSSP_REQUEST_TARGET |
+		NTLMSSP_NEGOTIATE_128 | NTLMSSP_NEGOTIATE_UNICODE |
+		NTLMSSP_NEGOTIATE_NTLM | NTLMSSP_NEGOTIATE_EXTENDED_SEC |
+		NTLMSSP_NEGOTIATE_ALWAYS_SIGN | NTLMSSP_NEGOTIATE_SEAL |
+		NTLMSSP_NEGOTIATE_SIGN | NTLMSSP_NEGOTIATE_VERSION;
+	if (!server->session_estab || ses->ntlmssp->sesskey_per_smbsess)
+		flags |= NTLMSSP_NEGOTIATE_KEY_XCH;
+
+	sec_blob->Version.ProductMajorVersion = LINUX_VERSION_MAJOR;
+	sec_blob->Version.ProductMinorVersion = LINUX_VERSION_PATCHLEVEL;
+	sec_blob->Version.ProductBuild = cpu_to_le16(SMB3_PRODUCT_BUILD);
+	sec_blob->Version.NTLMRevisionCurrent = NTLMSSP_REVISION_W2K3;
+
+	tmp = *pbuffer + sizeof(struct negotiate_message);
+	ses->ntlmssp->client_flags = flags;
+	sec_blob->NegotiateFlags = cpu_to_le32(flags);
+
+	/* these fields should be null in negotiate phase MS-NLMP 3.1.5.1.1 */
+	cifs_security_buffer_from_str(&sec_blob->DomainName,
+				      NULL,
+				      CIFS_MAX_DOMAINNAME_LEN,
+				      *pbuffer, &tmp,
+				      nls_cp);
+
+	cifs_security_buffer_from_str(&sec_blob->WorkstationName,
+				      NULL,
+				      CIFS_MAX_WORKSTATION_LEN,
+				      *pbuffer, &tmp,
+				      nls_cp);
+
+	*buflen = tmp - *pbuffer;
+setup_ntlm_smb3_neg_ret:
+	return rc;
+}
+
+
 int build_ntlmssp_auth_blob(unsigned char **pbuffer,
 					u16 *buflen,
 				   struct cifs_ses *ses,
+				   struct TCP_Server_Info *server,
 				   const struct nls_table *nls_cp)
 {
 	int rc;
@@ -848,7 +1087,7 @@ int build_ntlmssp_auth_blob(unsigned char **pbuffer,
 
 	cifs_security_buffer_from_str(&sec_blob->WorkstationName,
 				      ses->workstation_name,
-				      CIFS_MAX_WORKSTATION_LEN,
+				      ntlmssp_workstation_name_size(ses),
 				      *pbuffer, &tmp,
 				      nls_cp);
 
@@ -912,6 +1151,7 @@ cifs_select_sectype(struct TCP_Server_Info *server, enum securityEnum requested)
 struct sess_data {
 	unsigned int xid;
 	struct cifs_ses *ses;
+	struct TCP_Server_Info *server;
 	struct nls_table *nls_cp;
 	void (*func)(struct sess_data *);
 	int result;
@@ -927,6 +1167,7 @@ struct sess_data {
 	struct kvec iov[3];
 };
 
+#ifdef CONFIG_CIFS_ALLOW_INSECURE_LEGACY
 static int
 sess_alloc_buffer(struct sess_data *sess_data, int wct)
 {
@@ -968,41 +1209,45 @@ out_free_smb_buf:
 static void
 sess_free_buffer(struct sess_data *sess_data)
 {
+	struct kvec *iov = sess_data->iov;
+
+	/*
+	 * Zero the session data before freeing, as it might contain sensitive info (keys, etc).
+	 * Note that iov[1] is already freed by caller.
+	 */
+	if (sess_data->buf0_type != CIFS_NO_BUFFER && iov[0].iov_base)
+		memzero_explicit(iov[0].iov_base, iov[0].iov_len);
 
-	free_rsp_buf(sess_data->buf0_type, sess_data->iov[0].iov_base);
+	free_rsp_buf(sess_data->buf0_type, iov[0].iov_base);
 	sess_data->buf0_type = CIFS_NO_BUFFER;
-	kfree(sess_data->iov[2].iov_base);
+	kfree_sensitive(iov[2].iov_base);
 }
 
 static int
 sess_establish_session(struct sess_data *sess_data)
 {
 	struct cifs_ses *ses = sess_data->ses;
+	struct TCP_Server_Info *server = sess_data->server;
 
-	mutex_lock(&ses->server->srv_mutex);
-	if (!ses->server->session_estab) {
-		if (ses->server->sign) {
-			ses->server->session_key.response =
+	cifs_server_lock(server);
+	if (!server->session_estab) {
+		if (server->sign) {
+			server->session_key.response =
 				kmemdup(ses->auth_key.response,
 				ses->auth_key.len, GFP_KERNEL);
-			if (!ses->server->session_key.response) {
-				mutex_unlock(&ses->server->srv_mutex);
+			if (!server->session_key.response) {
+				cifs_server_unlock(server);
 				return -ENOMEM;
 			}
-			ses->server->session_key.len =
+			server->session_key.len =
 						ses->auth_key.len;
 		}
-		ses->server->sequence_number = 0x2;
-		ses->server->session_estab = true;
+		server->sequence_number = 0x2;
+		server->session_estab = true;
 	}
-	mutex_unlock(&ses->server->srv_mutex);
+	cifs_server_unlock(server);
 
 	cifs_dbg(FYI, "CIFS session established successfully\n");
-	spin_lock(&GlobalMid_Lock);
-	ses->status = CifsGood;
-	ses->need_reconnect = false;
-	spin_unlock(&GlobalMid_Lock);
-
 	return 0;
 }
 
@@ -1036,6 +1281,7 @@ sess_auth_ntlmv2(struct sess_data *sess_data)
 	SESSION_SETUP_ANDX *pSMB;
 	char *bcc_ptr;
 	struct cifs_ses *ses = sess_data->ses;
+	struct TCP_Server_Info *server = sess_data->server;
 	__u32 capabilities;
 	__u16 bytes_remaining;
 
@@ -1047,7 +1293,7 @@ sess_auth_ntlmv2(struct sess_data *sess_data)
 
 	pSMB = (SESSION_SETUP_ANDX *)sess_data->iov[0].iov_base;
 	bcc_ptr = sess_data->iov[2].iov_base;
-	capabilities = cifs_ssetup_hdr(ses, pSMB);
+	capabilities = cifs_ssetup_hdr(ses, server, pSMB);
 
 	pSMB->req_no_secext.Capabilities = cpu_to_le32(capabilities);
 
@@ -1076,7 +1322,7 @@ sess_auth_ntlmv2(struct sess_data *sess_data)
 	}
 
 	if (ses->capabilities & CAP_UNICODE) {
-		if (sess_data->iov[0].iov_len % 2) {
+		if (!IS_ALIGNED(sess_data->iov[0].iov_len, 2)) {
 			*bcc_ptr = 0;
 			bcc_ptr++;
 		}
@@ -1116,7 +1362,7 @@ sess_auth_ntlmv2(struct sess_data *sess_data)
 		/* no string area to decode, do nothing */
 	} else if (smb_buf->Flags2 & SMBFLG2_UNICODE) {
 		/* unicode string area must be word-aligned */
-		if (((unsigned long) bcc_ptr - (unsigned long) smb_buf) % 2) {
+		if (!IS_ALIGNED((unsigned long)bcc_ptr - (unsigned long)smb_buf, 2)) {
 			++bcc_ptr;
 			--bytes_remaining;
 		}
@@ -1132,7 +1378,7 @@ out:
 	sess_data->result = rc;
 	sess_data->func = NULL;
 	sess_free_buffer(sess_data);
-	kfree(ses->auth_key.response);
+	kfree_sensitive(ses->auth_key.response);
 	ses->auth_key.response = NULL;
 }
 
@@ -1145,6 +1391,7 @@ sess_auth_kerberos(struct sess_data *sess_data)
 	SESSION_SETUP_ANDX *pSMB;
 	char *bcc_ptr;
 	struct cifs_ses *ses = sess_data->ses;
+	struct TCP_Server_Info *server = sess_data->server;
 	__u32 capabilities;
 	__u16 bytes_remaining;
 	struct key *spnego_key = NULL;
@@ -1159,9 +1406,9 @@ sess_auth_kerberos(struct sess_data *sess_data)
 
 	pSMB = (SESSION_SETUP_ANDX *)sess_data->iov[0].iov_base;
 	bcc_ptr = sess_data->iov[2].iov_base;
-	capabilities = cifs_ssetup_hdr(ses, pSMB);
+	capabilities = cifs_ssetup_hdr(ses, server, pSMB);
 
-	spnego_key = cifs_get_spnego_key(ses);
+	spnego_key = cifs_get_spnego_key(ses, server);
 	if (IS_ERR(spnego_key)) {
 		rc = PTR_ERR(spnego_key);
 		spnego_key = NULL;
@@ -1199,8 +1446,7 @@ sess_auth_kerberos(struct sess_data *sess_data)
 
 	if (ses->capabilities & CAP_UNICODE) {
 		/* unicode strings must be word aligned */
-		if ((sess_data->iov[0].iov_len
-			+ sess_data->iov[1].iov_len) % 2) {
+		if (!IS_ALIGNED(sess_data->iov[0].iov_len + sess_data->iov[1].iov_len, 2)) {
 			*bcc_ptr = 0;
 			bcc_ptr++;
 		}
@@ -1251,7 +1497,7 @@ sess_auth_kerberos(struct sess_data *sess_data)
 		/* no string area to decode, do nothing */
 	} else if (smb_buf->Flags2 & SMBFLG2_UNICODE) {
 		/* unicode string area must be word-aligned */
-		if (((unsigned long) bcc_ptr - (unsigned long) smb_buf) % 2) {
+		if (!IS_ALIGNED((unsigned long)bcc_ptr - (unsigned long)smb_buf, 2)) {
 			++bcc_ptr;
 			--bytes_remaining;
 		}
@@ -1270,7 +1516,7 @@ out:
 	sess_data->result = rc;
 	sess_data->func = NULL;
 	sess_free_buffer(sess_data);
-	kfree(ses->auth_key.response);
+	kfree_sensitive(ses->auth_key.response);
 	ses->auth_key.response = NULL;
 }
 
@@ -1285,12 +1531,13 @@ _sess_auth_rawntlmssp_assemble_req(struct sess_data *sess_data)
 {
 	SESSION_SETUP_ANDX *pSMB;
 	struct cifs_ses *ses = sess_data->ses;
+	struct TCP_Server_Info *server = sess_data->server;
 	__u32 capabilities;
 	char *bcc_ptr;
 
 	pSMB = (SESSION_SETUP_ANDX *)sess_data->iov[0].iov_base;
 
-	capabilities = cifs_ssetup_hdr(ses, pSMB);
+	capabilities = cifs_ssetup_hdr(ses, server, pSMB);
 	if ((pSMB->req.hdr.Flags2 & SMBFLG2_UNICODE) == 0) {
 		cifs_dbg(VFS, "NTLMSSP requires Unicode support\n");
 		return -ENOSYS;
@@ -1302,7 +1549,7 @@ _sess_auth_rawntlmssp_assemble_req(struct sess_data *sess_data)
 
 	bcc_ptr = sess_data->iov[2].iov_base;
 	/* unicode strings must be word aligned */
-	if ((sess_data->iov[0].iov_len + sess_data->iov[1].iov_len) % 2) {
+	if (!IS_ALIGNED(sess_data->iov[0].iov_len + sess_data->iov[1].iov_len, 2)) {
 		*bcc_ptr = 0;
 		bcc_ptr++;
 	}
@@ -1324,6 +1571,7 @@ sess_auth_rawntlmssp_negotiate(struct sess_data *sess_data)
 	struct smb_hdr *smb_buf;
 	SESSION_SETUP_ANDX *pSMB;
 	struct cifs_ses *ses = sess_data->ses;
+	struct TCP_Server_Info *server = sess_data->server;
 	__u16 bytes_remaining;
 	char *bcc_ptr;
 	unsigned char *ntlmsspblob = NULL;
@@ -1351,10 +1599,10 @@ sess_auth_rawntlmssp_negotiate(struct sess_data *sess_data)
 
 	/* Build security blob before we assemble the request */
 	rc = build_ntlmssp_negotiate_blob(&ntlmsspblob,
-				     &blob_len, ses,
+				     &blob_len, ses, server,
 				     sess_data->nls_cp);
 	if (rc)
-		goto out;
+		goto out_free_ntlmsspblob;
 
 	sess_data->iov[1].iov_len = blob_len;
 	sess_data->iov[1].iov_base = ntlmsspblob;
@@ -1362,7 +1610,7 @@ sess_auth_rawntlmssp_negotiate(struct sess_data *sess_data)
 
 	rc = _sess_auth_rawntlmssp_assemble_req(sess_data);
 	if (rc)
-		goto out;
+		goto out_free_ntlmsspblob;
 
 	rc = sess_sendreceive(sess_data);
 
@@ -1376,14 +1624,14 @@ sess_auth_rawntlmssp_negotiate(struct sess_data *sess_data)
 		rc = 0;
 
 	if (rc)
-		goto out;
+		goto out_free_ntlmsspblob;
 
 	cifs_dbg(FYI, "rawntlmssp session setup challenge phase\n");
 
 	if (smb_buf->WordCount != 4) {
 		rc = -EIO;
 		cifs_dbg(VFS, "bad word count %d\n", smb_buf->WordCount);
-		goto out;
+		goto out_free_ntlmsspblob;
 	}
 
 	ses->Suid = smb_buf->Uid;   /* UID left in wire format (le) */
@@ -1397,10 +1645,13 @@ sess_auth_rawntlmssp_negotiate(struct sess_data *sess_data)
 		cifs_dbg(VFS, "bad security blob length %d\n",
 				blob_len);
 		rc = -EINVAL;
-		goto out;
+		goto out_free_ntlmsspblob;
 	}
 
 	rc = decode_ntlmssp_challenge(bcc_ptr, blob_len, ses);
+
+out_free_ntlmsspblob:
+	kfree_sensitive(ntlmsspblob);
 out:
 	sess_free_buffer(sess_data);
 
@@ -1410,9 +1661,9 @@ out:
 	}
 
 	/* Else error. Cleanup */
-	kfree(ses->auth_key.response);
+	kfree_sensitive(ses->auth_key.response);
 	ses->auth_key.response = NULL;
-	kfree(ses->ntlmssp);
+	kfree_sensitive(ses->ntlmssp);
 	ses->ntlmssp = NULL;
 
 	sess_data->func = NULL;
@@ -1426,6 +1677,7 @@ sess_auth_rawntlmssp_authenticate(struct sess_data *sess_data)
 	struct smb_hdr *smb_buf;
 	SESSION_SETUP_ANDX *pSMB;
 	struct cifs_ses *ses = sess_data->ses;
+	struct TCP_Server_Info *server = sess_data->server;
 	__u16 bytes_remaining;
 	char *bcc_ptr;
 	unsigned char *ntlmsspblob = NULL;
@@ -1442,7 +1694,8 @@ sess_auth_rawntlmssp_authenticate(struct sess_data *sess_data)
 	pSMB = (SESSION_SETUP_ANDX *)sess_data->iov[0].iov_base;
 	smb_buf = (struct smb_hdr *)pSMB;
 	rc = build_ntlmssp_auth_blob(&ntlmsspblob,
-					&blob_len, ses, sess_data->nls_cp);
+					&blob_len, ses, server,
+					sess_data->nls_cp);
 	if (rc)
 		goto out_free_ntlmsspblob;
 	sess_data->iov[1].iov_len = blob_len;
@@ -1497,7 +1750,7 @@ sess_auth_rawntlmssp_authenticate(struct sess_data *sess_data)
 		/* no string area to decode, do nothing */
 	} else if (smb_buf->Flags2 & SMBFLG2_UNICODE) {
 		/* unicode string area must be word-aligned */
-		if (((unsigned long) bcc_ptr - (unsigned long) smb_buf) % 2) {
+		if (!IS_ALIGNED((unsigned long)bcc_ptr - (unsigned long)smb_buf, 2)) {
 			++bcc_ptr;
 			--bytes_remaining;
 		}
@@ -1509,28 +1762,30 @@ sess_auth_rawntlmssp_authenticate(struct sess_data *sess_data)
 	}
 
 out_free_ntlmsspblob:
-	kfree(ntlmsspblob);
+	kfree_sensitive(ntlmsspblob);
 out:
 	sess_free_buffer(sess_data);
 
-	 if (!rc)
+	if (!rc)
 		rc = sess_establish_session(sess_data);
 
 	/* Cleanup */
-	kfree(ses->auth_key.response);
+	kfree_sensitive(ses->auth_key.response);
 	ses->auth_key.response = NULL;
-	kfree(ses->ntlmssp);
+	kfree_sensitive(ses->ntlmssp);
 	ses->ntlmssp = NULL;
 
 	sess_data->func = NULL;
 	sess_data->result = rc;
 }
 
-static int select_sec(struct cifs_ses *ses, struct sess_data *sess_data)
+static int select_sec(struct sess_data *sess_data)
 {
 	int type;
+	struct cifs_ses *ses = sess_data->ses;
+	struct TCP_Server_Info *server = sess_data->server;
 
-	type = cifs_select_sectype(ses->server, ses->sectype);
+	type = cifs_select_sectype(server, ses->sectype);
 	cifs_dbg(FYI, "sess setup type %d\n", type);
 	if (type == Unspecified) {
 		cifs_dbg(VFS, "Unable to select appropriate authentication method!\n");
@@ -1561,7 +1816,8 @@ static int select_sec(struct cifs_ses *ses, struct sess_data *sess_data)
 }
 
 int CIFS_SessSetup(const unsigned int xid, struct cifs_ses *ses,
-		    const struct nls_table *nls_cp)
+		   struct TCP_Server_Info *server,
+		   const struct nls_table *nls_cp)
 {
 	int rc = 0;
 	struct sess_data *sess_data;
@@ -1575,15 +1831,16 @@ int CIFS_SessSetup(const unsigned int xid, struct cifs_ses *ses,
 	if (!sess_data)
 		return -ENOMEM;
 
-	rc = select_sec(ses, sess_data);
-	if (rc)
-		goto out;
-
 	sess_data->xid = xid;
 	sess_data->ses = ses;
+	sess_data->server = server;
 	sess_data->buf0_type = CIFS_NO_BUFFER;
 	sess_data->nls_cp = (struct nls_table *) nls_cp;
 
+	rc = select_sec(sess_data);
+	if (rc)
+		goto out;
+
 	while (sess_data->func)
 		sess_data->func(sess_data);
 
@@ -1591,6 +1848,7 @@ int CIFS_SessSetup(const unsigned int xid, struct cifs_ses *ses,
 	rc = sess_data->result;
 
 out:
-	kfree(sess_data);
+	kfree_sensitive(sess_data);
 	return rc;
 }
+#endif /* CONFIG_CIFS_ALLOW_INSECURE_LEGACY */