This is a note to let you know that I've just added the patch titled smb3: when mounting with multichannel include it in requested capabilities to the 5.10-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: smb3-when-mounting-with-multichannel-include-it-in-requested-capabilities.patch and it can be found in the queue-5.10 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. >From 679971e7213174efb56abc8fab1299d0a88db0e8 Mon Sep 17 00:00:00 2001 From: Steve French <stfrench@xxxxxxxxxxxxx> Date: Fri, 7 May 2021 18:24:11 -0500 Subject: smb3: when mounting with multichannel include it in requested capabilities From: Steve French <stfrench@xxxxxxxxxxxxx> commit 679971e7213174efb56abc8fab1299d0a88db0e8 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@xxxxxxxxxx> Reviewed-by: Shyam Prasad N <sprasad@xxxxxxxxxxxxx> Cc: <stable@xxxxxxxxxxxxxxx> # v5.8+ Signed-off-by: Steve French <stfrench@xxxxxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- fs/cifs/smb2pdu.c | 5 +++++ 1 file changed, 5 insertions(+) --- a/fs/cifs/smb2pdu.c +++ b/fs/cifs/smb2pdu.c @@ -840,6 +840,8 @@ SMB2_negotiate(const unsigned int xid, s 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 unsign 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); Patches currently in stable-queue which might be from stfrench@xxxxxxxxxxxxx are queue-5.10/smb2-fix-use-after-free-in-smb2_ioctl_query_info.patch queue-5.10/cifs-return-correct-error-code-from-smb2_get_enc_key.patch queue-5.10/cifs-detect-dead-connections-only-when-echoes-are-enabled.patch queue-5.10/cifs-fix-out-of-bound-memory-access-when-calling-smb3_notify-at-mount-point.patch queue-5.10/smb3-do-not-attempt-multichannel-to-server-which-does-not-support-it.patch queue-5.10/smb3-when-mounting-with-multichannel-include-it-in-requested-capabilities.patch