ksmbd: return unsupported error on smb1 mount

commit 39b291b86b5988bf8753c3874d5c773399d09b96 upstream.

ksmbd disconnect connection when mounting with vers=smb1.
ksmbd should send smb1 negotiate response to client for correct
unsupported error return. This patch add needed SMB1 macros and fill
NegProt part of the response for smb1 negotiate response.

Cc: stable@vger.kernel.org
Reported-by: Steve French <stfrench@microsoft.com>
Reviewed-by: Sergey Senozhatsky <senozhatsky@chromium.org>
Signed-off-by: Namjae Jeon <linkinjeon@kernel.org>
Signed-off-by: Steve French <stfrench@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/fs/ksmbd/connection.c b/fs/ksmbd/connection.c
index ce0edf926c2af22105fd0fc8dcd6ad3b4fbdbfe5..6105649b4ebb07f35efb8efb5528b0c9b4fc76df 100644 (file)
--- a/fs/ksmbd/connection.c
+++ b/fs/ksmbd/connection.c
@@ -313,13 +313,10 @@ int ksmbd_conn_handler_loop(void *p)
                }
 
                /*
-                * Check if pdu size is valid (min : smb header size,
-                * max : 0x00FFFFFF).
+                * Check maximum pdu size(0x00FFFFFF).
                 */
-               if (pdu_size < __SMB2_HEADER_STRUCTURE_SIZE ||
-                   pdu_size > MAX_STREAM_PROT_LEN) {
+               if (pdu_size > MAX_STREAM_PROT_LEN)
                        break;
-               }
 
                /* 4 for rfc1002 length field */
                size = pdu_size + 4;

diff --git a/fs/ksmbd/smb_common.c b/fs/ksmbd/smb_common.c
index 7fbd3b9c48977b91ae9533179a685a5df9790cf5..f034b75c6d7f452390440f3cfd2565f2e6cf0ef9 100644 (file)
--- a/fs/ksmbd/smb_common.c
+++ b/fs/ksmbd/smb_common.c
@@ -442,9 +442,26 @@ static int smb_handle_negotiate(struct ksmbd_work *work)
 {
        struct smb_negotiate_rsp *neg_rsp = work->response_buf;
 
-       ksmbd_debug(SMB, "Unsupported SMB protocol\n");
-       neg_rsp->hdr.Status.CifsError = STATUS_INVALID_LOGON_TYPE;
-       return -EINVAL;
+       ksmbd_debug(SMB, "Unsupported SMB1 protocol\n");
+
+       /*
+        * Remove 4 byte direct TCP header, add 2 byte bcc and
+        * 2 byte DialectIndex.
+        */
+       *(__be32 *)work->response_buf =
+               cpu_to_be32(sizeof(struct smb_hdr) - 4 + 2 + 2);
+       neg_rsp->hdr.Status.CifsError = STATUS_SUCCESS;
+
+       neg_rsp->hdr.Command = SMB_COM_NEGOTIATE;
+       *(__le32 *)neg_rsp->hdr.Protocol = SMB1_PROTO_NUMBER;
+       neg_rsp->hdr.Flags = SMBFLG_RESPONSE;
+       neg_rsp->hdr.Flags2 = SMBFLG2_UNICODE | SMBFLG2_ERR_STATUS |
+               SMBFLG2_EXT_SEC | SMBFLG2_IS_LONG_NAME;
+
+       neg_rsp->hdr.WordCount = 1;
+       neg_rsp->DialectIndex = cpu_to_le16(work->conn->dialect);
+       neg_rsp->ByteCount = 0;
+       return 0;
 }
 
 int ksmbd_smb_negotiate_common(struct ksmbd_work *work, unsigned int command)

diff --git a/fs/ksmbd/smb_common.h b/fs/ksmbd/smb_common.h
index 1eba8dabaf317b90ae72a63c2ec7ce7749db50c9..b9fe3fa149c2e093af34b274054ac11a2afd8e9c 100644 (file)
--- a/fs/ksmbd/smb_common.h
+++ b/fs/ksmbd/smb_common.h
@@ -205,8 +205,15 @@
 
 #define SMB1_PROTO_NUMBER              cpu_to_le32(0x424d53ff)
 #define SMB_COM_NEGOTIATE              0x72
-
 #define SMB1_CLIENT_GUID_SIZE          (16)
+
+#define SMBFLG_RESPONSE 0x80   /* this PDU is a response from server */
+
+#define SMBFLG2_IS_LONG_NAME   cpu_to_le16(0x40)
+#define SMBFLG2_EXT_SEC                cpu_to_le16(0x800)
+#define SMBFLG2_ERR_STATUS     cpu_to_le16(0x4000)
+#define SMBFLG2_UNICODE                cpu_to_le16(0x8000)
+
 struct smb_hdr {
        __be32 smb_buf_length;
        __u8 Protocol[4];
@@ -246,28 +253,7 @@ struct smb_negotiate_req {
 struct smb_negotiate_rsp {
        struct smb_hdr hdr;     /* wct = 17 */
        __le16 DialectIndex; /* 0xFFFF = no dialect acceptable */
-       __u8 SecurityMode;
-       __le16 MaxMpxCount;
-       __le16 MaxNumberVcs;
-       __le32 MaxBufferSize;
-       __le32 MaxRawSize;
-       __le32 SessionKey;
-       __le32 Capabilities;    /* see below */
-       __le32 SystemTimeLow;
-       __le32 SystemTimeHigh;
-       __le16 ServerTimeZone;
-       __u8 EncryptionKeyLength;
        __le16 ByteCount;
-       union {
-               unsigned char EncryptionKey[8]; /* cap extended security off */
-               /* followed by Domain name - if extended security is off */
-               /* followed by 16 bytes of server GUID */
-               /* then security blob if cap_extended_security negotiated */
-               struct {
-                       unsigned char GUID[SMB1_CLIENT_GUID_SIZE];
-                       unsigned char SecurityBlob[1];
-               } __packed extended_response;
-       } __packed u;
 } __packed;
 
 struct filesystem_attribute_info {