smb3: when mounting with multichannel include it in requested capabilities

commit 679971e721 upstream.

In the SMB3/SMB3.1.1 negotiate protocol request, we are supposed to
advertise CAP_MULTICHANNEL capability when establishing multiple
channels has been requested by the user doing the mount. See MS-SMB2
sections 2.2.3 and 3.2.5.2

Without setting it there is some risk that multichannel could fail
if the server interpreted the field strictly.

Reviewed-By: Tom Talpey <tom@talpey.com>
Reviewed-by: Shyam Prasad N <sprasad@microsoft.com>
Cc: <stable@vger.kernel.org> # v5.8+
Signed-off-by: Steve French <stfrench@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Steve French 2021-05-07 18:24:11 -05:00 committed by Greg Kroah-Hartman
parent 5781c9df77
commit 796b826375

View file

@ -840,6 +840,8 @@ SMB2_negotiate(const unsigned int xid, struct cifs_ses *ses)
req->SecurityMode = 0;
req->Capabilities = cpu_to_le32(server->vals->req_capabilities);
if (ses->chan_max > 1)
req->Capabilities |= cpu_to_le32(SMB2_GLOBAL_CAP_MULTI_CHANNEL);
/* ClientGUID must be zero for SMB2.02 dialect */
if (server->vals->protocol_id == SMB20_PROT_ID)
@ -1025,6 +1027,9 @@ int smb3_validate_negotiate(const unsigned int xid, struct cifs_tcon *tcon)
pneg_inbuf->Capabilities =
cpu_to_le32(server->vals->req_capabilities);
if (tcon->ses->chan_max > 1)
pneg_inbuf->Capabilities |= cpu_to_le32(SMB2_GLOBAL_CAP_MULTI_CHANNEL);
memcpy(pneg_inbuf->Guid, server->client_guid,
SMB2_CLIENT_GUID_SIZE);