diff mbox series

PATCH] smb3: include current dialect (SMB3.1.1) when version 3 or greater requested on mount

Message ID CAH2r5mt7Z2wJTLFp1T0qtsrJb95FPKoffBN9WBM=JAi=HcyiOg@mail.gmail.com (mailing list archive)
State New, archived
Headers show
Series PATCH] smb3: include current dialect (SMB3.1.1) when version 3 or greater requested on mount | expand

Commit Message

Steve French Feb. 2, 2021, 6:15 a.m. UTC 
SMB3.1.1 is the newest, and preferred dialect, and is included in
the requested dialect list by default (ie if no vers= is specified
on mount) but it should also be requested if SMB3 or later is requested
(vers=3 instead of a specific dialect: vers=2.1, vers=3.02 or vers=3.0).

Currently specifying "vers=3" only requests smb3.0 and smb3.02 but this
patch fixes it to also request smb3.1.1 dialect, as it is the newest
and most secure dialect and is a "version 3 or later" dialect (the intent
of "vers=3").

Signed-off-by: Steve French <stfrench@microsoft.com>
Suggested-by: Pavel Shilovsky <pshilov@microsoft.com>
---
 fs/cifs/fs_context.c |  2 +-
 fs/cifs/smb2pdu.c    | 19 +++++++++++++------
 2 files changed, 14 insertions(+), 7 deletions(-)

  pneg_inbuf->Dialects[0] = cpu_to_le16(SMB21_PROT_ID);
@@ -1053,7 +1060,7 @@ int smb3_validate_negotiate(const unsigned int
xid, struct cifs_tcon *tcon)
  pneg_inbuf->Dialects[2] = cpu_to_le16(SMB302_PROT_ID);
  pneg_inbuf->Dialects[3] = cpu_to_le16(SMB311_PROT_ID);
  pneg_inbuf->DialectCount = cpu_to_le16(4);
- /* structure is big enough for 3 dialects */
+ /* structure is big enough for 4 dialects */
  inbuflen = sizeof(*pneg_inbuf);
  } else {
  /* otherwise specific dialect was requested */

Comments

Pavel Shilovsky Feb. 2, 2021, 5:58 p.m. UTC | #1 
пн, 1 февр. 2021 г. в 22:15, Steve French <smfrench@gmail.com>:
>
> SMB3.1.1 is the newest, and preferred dialect, and is included in
> the requested dialect list by default (ie if no vers= is specified
> on mount) but it should also be requested if SMB3 or later is requested
> (vers=3 instead of a specific dialect: vers=2.1, vers=3.02 or vers=3.0).
>
> Currently specifying "vers=3" only requests smb3.0 and smb3.02 but this
> patch fixes it to also request smb3.1.1 dialect, as it is the newest
> and most secure dialect and is a "version 3 or later" dialect (the intent
> of "vers=3").
>
> Signed-off-by: Steve French <stfrench@microsoft.com>
> Suggested-by: Pavel Shilovsky <pshilov@microsoft.com>
> ---
>  fs/cifs/fs_context.c |  2 +-
>  fs/cifs/smb2pdu.c    | 19 +++++++++++++------
>  2 files changed, 14 insertions(+), 7 deletions(-)
>
> diff --git a/fs/cifs/fs_context.c b/fs/cifs/fs_context.c
> index 5111aadfdb6b..479c24695281 100644
> --- a/fs/cifs/fs_context.c
> +++ b/fs/cifs/fs_context.c
> @@ -391,7 +391,7 @@ cifs_parse_smb_version(char *value, struct
> smb3_fs_context *ctx, bool is_smb3)
>   ctx->vals = &smb3any_values;
>   break;
>   case Smb_default:
> - ctx->ops = &smb30_operations; /* currently identical with 3.0 */
> + ctx->ops = &smb30_operations;
>   ctx->vals = &smbdefault_values;
>   break;
>   default:
> diff --git a/fs/cifs/smb2pdu.c b/fs/cifs/smb2pdu.c
> index 794fc3b68b4f..52625549c3b5 100644
> --- a/fs/cifs/smb2pdu.c
> +++ b/fs/cifs/smb2pdu.c
> @@ -814,8 +814,9 @@ SMB2_negotiate(const unsigned int xid, struct cifs_ses *ses)
>      SMB3ANY_VERSION_STRING) == 0) {
>   req->Dialects[0] = cpu_to_le16(SMB30_PROT_ID);
>   req->Dialects[1] = cpu_to_le16(SMB302_PROT_ID);
> - req->DialectCount = cpu_to_le16(2);
> - total_len += 4;
> + req->Dialects[2] = cpu_to_le16(SMB311_PROT_ID);
> + req->DialectCount = cpu_to_le16(3);
> + total_len += 6;
>   } else if (strcmp(server->vals->version_string,
>      SMBDEFAULT_VERSION_STRING) == 0) {
>   req->Dialects[0] = cpu_to_le16(SMB21_PROT_ID);
> @@ -848,6 +849,8 @@ SMB2_negotiate(const unsigned int xid, struct cifs_ses *ses)
>   memcpy(req->ClientGUID, server->client_guid,
>   SMB2_CLIENT_GUID_SIZE);
>   if ((server->vals->protocol_id == SMB311_PROT_ID) ||
> +     (strcmp(server->vals->version_string,
> +      SMB3ANY_VERSION_STRING) == 0) ||
>       (strcmp(server->vals->version_string,
>        SMBDEFAULT_VERSION_STRING) == 0))
>   assemble_neg_contexts(req, server, &total_len);
> @@ -883,6 +886,9 @@ SMB2_negotiate(const unsigned int xid, struct cifs_ses *ses)
>   cifs_server_dbg(VFS,
>   "SMB2.1 dialect returned but not requested\n");
>   return -EIO;
> + } else if (rsp->DialectRevision == cpu_to_le16(SMB311_PROT_ID)) {

I think we should include comment "/* ops set to 3.0 by default for
default so update */" as in smbdefault case to improve readability.

> + server->ops = &smb311_operations;
> + server->vals = &smb311_values;
>   }
>   } else if (strcmp(server->vals->version_string,
>      SMBDEFAULT_VERSION_STRING) == 0) {
> @@ -1042,10 +1048,11 @@ int smb3_validate_negotiate(const unsigned int
> xid, struct cifs_tcon *tcon)
>   SMB3ANY_VERSION_STRING) == 0) {
>   pneg_inbuf->Dialects[0] = cpu_to_le16(SMB30_PROT_ID);
>   pneg_inbuf->Dialects[1] = cpu_to_le16(SMB302_PROT_ID);
> - pneg_inbuf->DialectCount = cpu_to_le16(2);
> - /* structure is big enough for 3 dialects, sending only 2 */
> + pneg_inbuf->Dialects[2] = cpu_to_le16(SMB311_PROT_ID);
> + pneg_inbuf->DialectCount = cpu_to_le16(3);
> + /* SMB 2.1 not included so subtract one dialect from len */
>   inbuflen = sizeof(*pneg_inbuf) -
> - (2 * sizeof(pneg_inbuf->Dialects[0]));
> + (sizeof(pneg_inbuf->Dialects[0]));
>   } else if (strcmp(server->vals->version_string,
>   SMBDEFAULT_VERSION_STRING) == 0) {
>   pneg_inbuf->Dialects[0] = cpu_to_le16(SMB21_PROT_ID);
> @@ -1053,7 +1060,7 @@ int smb3_validate_negotiate(const unsigned int
> xid, struct cifs_tcon *tcon)
>   pneg_inbuf->Dialects[2] = cpu_to_le16(SMB302_PROT_ID);
>   pneg_inbuf->Dialects[3] = cpu_to_le16(SMB311_PROT_ID);
>   pneg_inbuf->DialectCount = cpu_to_le16(4);
> - /* structure is big enough for 3 dialects */
> + /* structure is big enough for 4 dialects */
>   inbuflen = sizeof(*pneg_inbuf);
>   } else {
>   /* otherwise specific dialect was requested */
>
> --
> Thanks,
>
> Steve

Looks good overall.

Reviewed-by: Pavel Shilovsky <pshilov@microsoft.com>
--
Best regards,
Pavel Shilovsky
Steve French Feb. 3, 2021, 4:05 a.m. UTC | #2 
updated as suggested (see attached) and merged into cifs-2.6.git for-next

On Tue, Feb 2, 2021 at 11:58 AM Pavel Shilovsky <piastryyy@gmail.com> wrote:
>
> пн, 1 февр. 2021 г. в 22:15, Steve French <smfrench@gmail.com>:
> >
> > SMB3.1.1 is the newest, and preferred dialect, and is included in
> > the requested dialect list by default (ie if no vers= is specified
> > on mount) but it should also be requested if SMB3 or later is requested
> > (vers=3 instead of a specific dialect: vers=2.1, vers=3.02 or vers=3.0).
> >
> > Currently specifying "vers=3" only requests smb3.0 and smb3.02 but this
> > patch fixes it to also request smb3.1.1 dialect, as it is the newest
> > and most secure dialect and is a "version 3 or later" dialect (the intent
> > of "vers=3").
> >
> > Signed-off-by: Steve French <stfrench@microsoft.com>
> > Suggested-by: Pavel Shilovsky <pshilov@microsoft.com>
> > ---
> >  fs/cifs/fs_context.c |  2 +-
> >  fs/cifs/smb2pdu.c    | 19 +++++++++++++------
> >  2 files changed, 14 insertions(+), 7 deletions(-)
> >
> > diff --git a/fs/cifs/fs_context.c b/fs/cifs/fs_context.c
> > index 5111aadfdb6b..479c24695281 100644
> > --- a/fs/cifs/fs_context.c
> > +++ b/fs/cifs/fs_context.c
> > @@ -391,7 +391,7 @@ cifs_parse_smb_version(char *value, struct
> > smb3_fs_context *ctx, bool is_smb3)
> >   ctx->vals = &smb3any_values;
> >   break;
> >   case Smb_default:
> > - ctx->ops = &smb30_operations; /* currently identical with 3.0 */
> > + ctx->ops = &smb30_operations;
> >   ctx->vals = &smbdefault_values;
> >   break;
> >   default:
> > diff --git a/fs/cifs/smb2pdu.c b/fs/cifs/smb2pdu.c
> > index 794fc3b68b4f..52625549c3b5 100644
> > --- a/fs/cifs/smb2pdu.c
> > +++ b/fs/cifs/smb2pdu.c
> > @@ -814,8 +814,9 @@ SMB2_negotiate(const unsigned int xid, struct cifs_ses *ses)
> >      SMB3ANY_VERSION_STRING) == 0) {
> >   req->Dialects[0] = cpu_to_le16(SMB30_PROT_ID);
> >   req->Dialects[1] = cpu_to_le16(SMB302_PROT_ID);
> > - req->DialectCount = cpu_to_le16(2);
> > - total_len += 4;
> > + req->Dialects[2] = cpu_to_le16(SMB311_PROT_ID);
> > + req->DialectCount = cpu_to_le16(3);
> > + total_len += 6;
> >   } else if (strcmp(server->vals->version_string,
> >      SMBDEFAULT_VERSION_STRING) == 0) {
> >   req->Dialects[0] = cpu_to_le16(SMB21_PROT_ID);
> > @@ -848,6 +849,8 @@ SMB2_negotiate(const unsigned int xid, struct cifs_ses *ses)
> >   memcpy(req->ClientGUID, server->client_guid,
> >   SMB2_CLIENT_GUID_SIZE);
> >   if ((server->vals->protocol_id == SMB311_PROT_ID) ||
> > +     (strcmp(server->vals->version_string,
> > +      SMB3ANY_VERSION_STRING) == 0) ||
> >       (strcmp(server->vals->version_string,
> >        SMBDEFAULT_VERSION_STRING) == 0))
> >   assemble_neg_contexts(req, server, &total_len);
> > @@ -883,6 +886,9 @@ SMB2_negotiate(const unsigned int xid, struct cifs_ses *ses)
> >   cifs_server_dbg(VFS,
> >   "SMB2.1 dialect returned but not requested\n");
> >   return -EIO;
> > + } else if (rsp->DialectRevision == cpu_to_le16(SMB311_PROT_ID)) {
>
> I think we should include comment "/* ops set to 3.0 by default for
> default so update */" as in smbdefault case to improve readability.
>
> > + server->ops = &smb311_operations;
> > + server->vals = &smb311_values;
> >   }
> >   } else if (strcmp(server->vals->version_string,
> >      SMBDEFAULT_VERSION_STRING) == 0) {
> > @@ -1042,10 +1048,11 @@ int smb3_validate_negotiate(const unsigned int
> > xid, struct cifs_tcon *tcon)
> >   SMB3ANY_VERSION_STRING) == 0) {
> >   pneg_inbuf->Dialects[0] = cpu_to_le16(SMB30_PROT_ID);
> >   pneg_inbuf->Dialects[1] = cpu_to_le16(SMB302_PROT_ID);
> > - pneg_inbuf->DialectCount = cpu_to_le16(2);
> > - /* structure is big enough for 3 dialects, sending only 2 */
> > + pneg_inbuf->Dialects[2] = cpu_to_le16(SMB311_PROT_ID);
> > + pneg_inbuf->DialectCount = cpu_to_le16(3);
> > + /* SMB 2.1 not included so subtract one dialect from len */
> >   inbuflen = sizeof(*pneg_inbuf) -
> > - (2 * sizeof(pneg_inbuf->Dialects[0]));
> > + (sizeof(pneg_inbuf->Dialects[0]));
> >   } else if (strcmp(server->vals->version_string,
> >   SMBDEFAULT_VERSION_STRING) == 0) {
> >   pneg_inbuf->Dialects[0] = cpu_to_le16(SMB21_PROT_ID);
> > @@ -1053,7 +1060,7 @@ int smb3_validate_negotiate(const unsigned int
> > xid, struct cifs_tcon *tcon)
> >   pneg_inbuf->Dialects[2] = cpu_to_le16(SMB302_PROT_ID);
> >   pneg_inbuf->Dialects[3] = cpu_to_le16(SMB311_PROT_ID);
> >   pneg_inbuf->DialectCount = cpu_to_le16(4);
> > - /* structure is big enough for 3 dialects */
> > + /* structure is big enough for 4 dialects */
> >   inbuflen = sizeof(*pneg_inbuf);
> >   } else {
> >   /* otherwise specific dialect was requested */
> >
> > --
> > Thanks,
> >
> > Steve
>
> Looks good overall.
>
> Reviewed-by: Pavel Shilovsky <pshilov@microsoft.com>
> --
> Best regards,
> Pavel Shilovsky
Shyam Prasad N Feb. 3, 2021, 11:22 a.m. UTC | #3 
Reviewed the patch in for-next.
Looks good to me.

Reviewed-by: Shyam Prasad N <sprasad@microsoft.com>

Regards,
Shyam

On Tue, Feb 2, 2021 at 8:23 PM Steve French <smfrench@gmail.com> wrote:
>
> updated as suggested (see attached) and merged into cifs-2.6.git for-next
>
> On Tue, Feb 2, 2021 at 11:58 AM Pavel Shilovsky <piastryyy@gmail.com> wrote:
> >
> > пн, 1 февр. 2021 г. в 22:15, Steve French <smfrench@gmail.com>:
> > >
> > > SMB3.1.1 is the newest, and preferred dialect, and is included in
> > > the requested dialect list by default (ie if no vers= is specified
> > > on mount) but it should also be requested if SMB3 or later is requested
> > > (vers=3 instead of a specific dialect: vers=2.1, vers=3.02 or vers=3.0).
> > >
> > > Currently specifying "vers=3" only requests smb3.0 and smb3.02 but this
> > > patch fixes it to also request smb3.1.1 dialect, as it is the newest
> > > and most secure dialect and is a "version 3 or later" dialect (the intent
> > > of "vers=3").
> > >
> > > Signed-off-by: Steve French <stfrench@microsoft.com>
> > > Suggested-by: Pavel Shilovsky <pshilov@microsoft.com>
> > > ---
> > >  fs/cifs/fs_context.c |  2 +-
> > >  fs/cifs/smb2pdu.c    | 19 +++++++++++++------
> > >  2 files changed, 14 insertions(+), 7 deletions(-)
> > >
> > > diff --git a/fs/cifs/fs_context.c b/fs/cifs/fs_context.c
> > > index 5111aadfdb6b..479c24695281 100644
> > > --- a/fs/cifs/fs_context.c
> > > +++ b/fs/cifs/fs_context.c
> > > @@ -391,7 +391,7 @@ cifs_parse_smb_version(char *value, struct
> > > smb3_fs_context *ctx, bool is_smb3)
> > >   ctx->vals = &smb3any_values;
> > >   break;
> > >   case Smb_default:
> > > - ctx->ops = &smb30_operations; /* currently identical with 3.0 */
> > > + ctx->ops = &smb30_operations;
> > >   ctx->vals = &smbdefault_values;
> > >   break;
> > >   default:
> > > diff --git a/fs/cifs/smb2pdu.c b/fs/cifs/smb2pdu.c
> > > index 794fc3b68b4f..52625549c3b5 100644
> > > --- a/fs/cifs/smb2pdu.c
> > > +++ b/fs/cifs/smb2pdu.c
> > > @@ -814,8 +814,9 @@ SMB2_negotiate(const unsigned int xid, struct cifs_ses *ses)
> > >      SMB3ANY_VERSION_STRING) == 0) {
> > >   req->Dialects[0] = cpu_to_le16(SMB30_PROT_ID);
> > >   req->Dialects[1] = cpu_to_le16(SMB302_PROT_ID);
> > > - req->DialectCount = cpu_to_le16(2);
> > > - total_len += 4;
> > > + req->Dialects[2] = cpu_to_le16(SMB311_PROT_ID);
> > > + req->DialectCount = cpu_to_le16(3);
> > > + total_len += 6;
> > >   } else if (strcmp(server->vals->version_string,
> > >      SMBDEFAULT_VERSION_STRING) == 0) {
> > >   req->Dialects[0] = cpu_to_le16(SMB21_PROT_ID);
> > > @@ -848,6 +849,8 @@ SMB2_negotiate(const unsigned int xid, struct cifs_ses *ses)
> > >   memcpy(req->ClientGUID, server->client_guid,
> > >   SMB2_CLIENT_GUID_SIZE);
> > >   if ((server->vals->protocol_id == SMB311_PROT_ID) ||
> > > +     (strcmp(server->vals->version_string,
> > > +      SMB3ANY_VERSION_STRING) == 0) ||
> > >       (strcmp(server->vals->version_string,
> > >        SMBDEFAULT_VERSION_STRING) == 0))
> > >   assemble_neg_contexts(req, server, &total_len);
> > > @@ -883,6 +886,9 @@ SMB2_negotiate(const unsigned int xid, struct cifs_ses *ses)
> > >   cifs_server_dbg(VFS,
> > >   "SMB2.1 dialect returned but not requested\n");
> > >   return -EIO;
> > > + } else if (rsp->DialectRevision == cpu_to_le16(SMB311_PROT_ID)) {
> >
> > I think we should include comment "/* ops set to 3.0 by default for
> > default so update */" as in smbdefault case to improve readability.
> >
> > > + server->ops = &smb311_operations;
> > > + server->vals = &smb311_values;
> > >   }
> > >   } else if (strcmp(server->vals->version_string,
> > >      SMBDEFAULT_VERSION_STRING) == 0) {
> > > @@ -1042,10 +1048,11 @@ int smb3_validate_negotiate(const unsigned int
> > > xid, struct cifs_tcon *tcon)
> > >   SMB3ANY_VERSION_STRING) == 0) {
> > >   pneg_inbuf->Dialects[0] = cpu_to_le16(SMB30_PROT_ID);
> > >   pneg_inbuf->Dialects[1] = cpu_to_le16(SMB302_PROT_ID);
> > > - pneg_inbuf->DialectCount = cpu_to_le16(2);
> > > - /* structure is big enough for 3 dialects, sending only 2 */
> > > + pneg_inbuf->Dialects[2] = cpu_to_le16(SMB311_PROT_ID);
> > > + pneg_inbuf->DialectCount = cpu_to_le16(3);
> > > + /* SMB 2.1 not included so subtract one dialect from len */
> > >   inbuflen = sizeof(*pneg_inbuf) -
> > > - (2 * sizeof(pneg_inbuf->Dialects[0]));
> > > + (sizeof(pneg_inbuf->Dialects[0]));
> > >   } else if (strcmp(server->vals->version_string,
> > >   SMBDEFAULT_VERSION_STRING) == 0) {
> > >   pneg_inbuf->Dialects[0] = cpu_to_le16(SMB21_PROT_ID);
> > > @@ -1053,7 +1060,7 @@ int smb3_validate_negotiate(const unsigned int
> > > xid, struct cifs_tcon *tcon)
> > >   pneg_inbuf->Dialects[2] = cpu_to_le16(SMB302_PROT_ID);
> > >   pneg_inbuf->Dialects[3] = cpu_to_le16(SMB311_PROT_ID);
> > >   pneg_inbuf->DialectCount = cpu_to_le16(4);
> > > - /* structure is big enough for 3 dialects */
> > > + /* structure is big enough for 4 dialects */
> > >   inbuflen = sizeof(*pneg_inbuf);
> > >   } else {
> > >   /* otherwise specific dialect was requested */
> > >
> > > --
> > > Thanks,
> > >
> > > Steve
> >
> > Looks good overall.
> >
> > Reviewed-by: Pavel Shilovsky <pshilov@microsoft.com>
> > --
> > Best regards,
> > Pavel Shilovsky
>
>
>
> --
> Thanks,
>
> Steve
diff mbox series

Patch

From e7055cdca03ea5522992345c9248cdbfed5c9d6a Mon Sep 17 00:00:00 2001
From: Steve French <stfrench@microsoft.com>
Date: Tue, 2 Feb 2021 00:03:58 -0600
Subject: [PATCH] smb3: negotiate current dialect (SMB3.1.1) when version 3 or
 greater requested

SMB3.1.1 is the newest, and preferred dialect, and is included in
the requested dialect list by default (ie if no vers= is specified
on mount) but it should also be requested if SMB3 or later is requested
(vers=3 instead of a specific dialect: vers=2.1, vers=3.02 or vers=3.0).

Currently specifying "vers=3" only requests smb3.0 and smb3.02 but this
patch fixes it to also request smb3.1.1 dialect, as it is the newest
and most secure dialect and is a "version 3 or later" dialect (the intent
of "vers=3" dialect).

Signed-off-by: Steve French <stfrench@microsoft.com>
Suggested-by: Pavel Shilovsky <pshilov@microsoft.com>
---
 fs/cifs/fs_context.c |  2 +-
 fs/cifs/smb2pdu.c    | 19 +++++++++++++------
 2 files changed, 14 insertions(+), 7 deletions(-)

diff --git a/fs/cifs/fs_context.c b/fs/cifs/fs_context.c
index 5111aadfdb6b..479c24695281 100644
--- a/fs/cifs/fs_context.c
+++ b/fs/cifs/fs_context.c
@@ -391,7 +391,7 @@  cifs_parse_smb_version(char *value, struct smb3_fs_context *ctx, bool is_smb3)
 		ctx->vals = &smb3any_values;
 		break;
 	case Smb_default:
-		ctx->ops = &smb30_operations; /* currently identical with 3.0 */
+		ctx->ops = &smb30_operations;
 		ctx->vals = &smbdefault_values;
 		break;
 	default:
diff --git a/fs/cifs/smb2pdu.c b/fs/cifs/smb2pdu.c
index 794fc3b68b4f..52625549c3b5 100644
--- a/fs/cifs/smb2pdu.c
+++ b/fs/cifs/smb2pdu.c
@@ -814,8 +814,9 @@  SMB2_negotiate(const unsigned int xid, struct cifs_ses *ses)
 		   SMB3ANY_VERSION_STRING) == 0) {
 		req->Dialects[0] = cpu_to_le16(SMB30_PROT_ID);
 		req->Dialects[1] = cpu_to_le16(SMB302_PROT_ID);
-		req->DialectCount = cpu_to_le16(2);
-		total_len += 4;
+		req->Dialects[2] = cpu_to_le16(SMB311_PROT_ID);
+		req->DialectCount = cpu_to_le16(3);
+		total_len += 6;
 	} else if (strcmp(server->vals->version_string,
 		   SMBDEFAULT_VERSION_STRING) == 0) {
 		req->Dialects[0] = cpu_to_le16(SMB21_PROT_ID);
@@ -848,6 +849,8 @@  SMB2_negotiate(const unsigned int xid, struct cifs_ses *ses)
 		memcpy(req->ClientGUID, server->client_guid,
 			SMB2_CLIENT_GUID_SIZE);
 		if ((server->vals->protocol_id == SMB311_PROT_ID) ||
+		    (strcmp(server->vals->version_string,
+		     SMB3ANY_VERSION_STRING) == 0) ||
 		    (strcmp(server->vals->version_string,
 		     SMBDEFAULT_VERSION_STRING) == 0))
 			assemble_neg_contexts(req, server, &total_len);
@@ -883,6 +886,9 @@  SMB2_negotiate(const unsigned int xid, struct cifs_ses *ses)
 			cifs_server_dbg(VFS,
 				"SMB2.1 dialect returned but not requested\n");
 			return -EIO;
+		} else if (rsp->DialectRevision == cpu_to_le16(SMB311_PROT_ID)) {
+			server->ops = &smb311_operations;
+			server->vals = &smb311_values;
 		}
 	} else if (strcmp(server->vals->version_string,
 		   SMBDEFAULT_VERSION_STRING) == 0) {
@@ -1042,10 +1048,11 @@  int smb3_validate_negotiate(const unsigned int xid, struct cifs_tcon *tcon)
 		SMB3ANY_VERSION_STRING) == 0) {
 		pneg_inbuf->Dialects[0] = cpu_to_le16(SMB30_PROT_ID);
 		pneg_inbuf->Dialects[1] = cpu_to_le16(SMB302_PROT_ID);
-		pneg_inbuf->DialectCount = cpu_to_le16(2);
-		/* structure is big enough for 3 dialects, sending only 2 */
+		pneg_inbuf->Dialects[2] = cpu_to_le16(SMB311_PROT_ID);
+		pneg_inbuf->DialectCount = cpu_to_le16(3);
+		/* SMB 2.1 not included so subtract one dialect from len */
 		inbuflen = sizeof(*pneg_inbuf) -
-				(2 * sizeof(pneg_inbuf->Dialects[0]));
+				(sizeof(pneg_inbuf->Dialects[0]));
 	} else if (strcmp(server->vals->version_string,
 		SMBDEFAULT_VERSION_STRING) == 0) {
 		pneg_inbuf->Dialects[0] = cpu_to_le16(SMB21_PROT_ID);
@@ -1053,7 +1060,7 @@  int smb3_validate_negotiate(const unsigned int xid, struct cifs_tcon *tcon)
 		pneg_inbuf->Dialects[2] = cpu_to_le16(SMB302_PROT_ID);
 		pneg_inbuf->Dialects[3] = cpu_to_le16(SMB311_PROT_ID);
 		pneg_inbuf->DialectCount = cpu_to_le16(4);
-		/* structure is big enough for 3 dialects */
+		/* structure is big enough for 4 dialects */
 		inbuflen = sizeof(*pneg_inbuf);
 	} else {
 		/* otherwise specific dialect was requested */
-- 
2.27.0