From 679971e7213174efb56abc8fab1299d0a88db0e8 Mon Sep 17 00:00:00 2001 From: Steve French Date: Fri, 7 May 2021 18:24:11 -0500 Subject: smb3: when mounting with multichannel include it in requested capabilities 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 Reviewed-by: Shyam Prasad N Cc: # v5.8+ Signed-off-by: Steve French --- fs/cifs/smb2pdu.c | 5 +++++ 1 file changed, 5 insertions(+) diff --git a/fs/cifs/smb2pdu.c b/fs/cifs/smb2pdu.c index e36c2a867783..a8bf43184773 100644 --- a/fs/cifs/smb2pdu.c +++ b/fs/cifs/smb2pdu.c @@ -841,6 +841,8 @@ 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) @@ -1032,6 +1034,9 @@ 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); -- cgit v1.2.3