The patch below does not apply to the 4.16-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to stable@vger.kernel.org.
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
From 23657ad7305ee8b263d27335abdd00917764c9cf Mon Sep 17 00:00:00 2001
From: Steve French stfrench@microsoft.com Date: Sun, 22 Apr 2018 15:14:58 -0500 Subject: [PATCH] SMB3: Fix 3.11 encryption to Windows and handle encrypted smb3 tcon
Temporarily disable AES-GCM, as AES-CCM is only currently enabled mechanism on client side. This fixes SMB3.11 encrypted mounts to Windows.
Also the tree connect request itself should be encrypted if requested encryption ("seal" on mount), in addition we should be enabling encryption in 3.11 based on whether we got any valid encryption ciphers back in negprot (the corresponding session flag is not set as it is in 3.0 and 3.02)
Signed-off-by: Steve French smfrench@gmail.com Reviewed-by: Pavel Shilovsky pshilov@microsoft.com Reviewed-by: Ronnie Sahlberg lsahlber@redhat.com CC: Stable stable@vger.kernel.org
diff --git a/fs/cifs/connect.c b/fs/cifs/connect.c index e8830f076a7f..a5aa158d535a 100644 --- a/fs/cifs/connect.c +++ b/fs/cifs/connect.c @@ -2959,6 +2959,22 @@ cifs_get_tcon(struct cifs_ses *ses, struct smb_vol *volume_info) } }
+ if (volume_info->seal) { + if (ses->server->vals->protocol_id == 0) { + cifs_dbg(VFS, + "SMB3 or later required for encryption\n"); + rc = -EOPNOTSUPP; + goto out_fail; + } else if (tcon->ses->server->capabilities & + SMB2_GLOBAL_CAP_ENCRYPTION) + tcon->seal = true; + else { + cifs_dbg(VFS, "Encryption is not supported on share\n"); + rc = -EOPNOTSUPP; + goto out_fail; + } + } + /* * BB Do we need to wrap session_mutex around this TCon call and Unix * SetFS as we do on SessSetup and reconnect? @@ -3007,22 +3023,6 @@ cifs_get_tcon(struct cifs_ses *ses, struct smb_vol *volume_info) tcon->use_resilient = true; }
- if (volume_info->seal) { - if (ses->server->vals->protocol_id == 0) { - cifs_dbg(VFS, - "SMB3 or later required for encryption\n"); - rc = -EOPNOTSUPP; - goto out_fail; - } else if (tcon->ses->server->capabilities & - SMB2_GLOBAL_CAP_ENCRYPTION) - tcon->seal = true; - else { - cifs_dbg(VFS, "Encryption is not supported on share\n"); - rc = -EOPNOTSUPP; - goto out_fail; - } - } - /* * We can have only one retry value for a connection to a share so for * resources mounted more than once to the same server share the last diff --git a/fs/cifs/smb2pdu.c b/fs/cifs/smb2pdu.c index 0f044c4a2dc9..9aea138dd71f 100644 --- a/fs/cifs/smb2pdu.c +++ b/fs/cifs/smb2pdu.c @@ -383,10 +383,10 @@ static void build_encrypt_ctxt(struct smb2_encryption_neg_context *pneg_ctxt) { pneg_ctxt->ContextType = SMB2_ENCRYPTION_CAPABILITIES; - pneg_ctxt->DataLength = cpu_to_le16(6); - pneg_ctxt->CipherCount = cpu_to_le16(2); - pneg_ctxt->Ciphers[0] = SMB2_ENCRYPTION_AES128_GCM; - pneg_ctxt->Ciphers[1] = SMB2_ENCRYPTION_AES128_CCM; + pneg_ctxt->DataLength = cpu_to_le16(4); /* Cipher Count + le16 cipher */ + pneg_ctxt->CipherCount = cpu_to_le16(1); +/* pneg_ctxt->Ciphers[0] = SMB2_ENCRYPTION_AES128_GCM;*/ /* not supported yet */ + pneg_ctxt->Ciphers[0] = SMB2_ENCRYPTION_AES128_CCM; }
static void @@ -444,6 +444,7 @@ static int decode_encrypt_ctx(struct TCP_Server_Info *server, return -EINVAL; } server->cipher_type = ctxt->Ciphers[0]; + server->capabilities |= SMB2_GLOBAL_CAP_ENCRYPTION; return 0; }
diff --git a/fs/cifs/smb2pdu.h b/fs/cifs/smb2pdu.h index 6093e5142b2b..d28f358022c5 100644 --- a/fs/cifs/smb2pdu.h +++ b/fs/cifs/smb2pdu.h @@ -297,7 +297,7 @@ struct smb2_encryption_neg_context { __le16 DataLength; __le32 Reserved; __le16 CipherCount; /* AES-128-GCM and AES-128-CCM */ - __le16 Ciphers[2]; /* Ciphers[0] since only one used now */ + __le16 Ciphers[1]; /* Ciphers[0] since only one used now */ } __packed;
struct smb2_negotiate_rsp {