cifs: Add minor debug message during negprot

Check for unknown security mode flags during negotiate protocol
if debugging enabled.

Signed-off-by: Steve French <smfrench@gmail.com>
Reviewed-by: Pavel Shilovsky <pshilov@microsoft.com>

diff --git a/fs/cifs/smb2pdu.c b/fs/cifs/smb2pdu.c
index 0e04b577758ddc2f267a900d138a133d6bfc593f..f7741cee2a4cc73366dba1c724a8c74c38f11744 100644 (file)
--- a/fs/cifs/smb2pdu.c
+++ b/fs/cifs/smb2pdu.c
@@ -584,8 +584,10 @@ SMB2_negotiate(const unsigned int xid, struct cifs_ses *ses)
                               SMB2_MAX_BUFFER_SIZE);
        server->max_read = le32_to_cpu(rsp->MaxReadSize);
        server->max_write = le32_to_cpu(rsp->MaxWriteSize);
-       /* BB Do we need to validate the SecurityMode? */
        server->sec_mode = le16_to_cpu(rsp->SecurityMode);
+       if ((server->sec_mode & SMB2_SEC_MODE_FLAGS_ALL) != server->sec_mode)
+               cifs_dbg(FYI, "Server returned unexpected security mode 0x%x\n",
+                               server->sec_mode);
        server->capabilities = le32_to_cpu(rsp->Capabilities);
        /* Internal types */
        server->capabilities |= SMB2_NT_FIND | SMB2_LARGE_FILES;

diff --git a/fs/cifs/smb2pdu.h b/fs/cifs/smb2pdu.h
index 8b901c69a65a825bc310aaf44a7de0415e11c8be..253e2c7c952f64e1fef446fbad1895dfafe753fa 100644 (file)
--- a/fs/cifs/smb2pdu.h
+++ b/fs/cifs/smb2pdu.h
@@ -249,6 +249,8 @@ struct smb2_negotiate_req {
 /* SecurityMode flags */
 #define        SMB2_NEGOTIATE_SIGNING_ENABLED  0x0001
 #define SMB2_NEGOTIATE_SIGNING_REQUIRED        0x0002
+#define SMB2_SEC_MODE_FLAGS_ALL                0x0003
+
 /* Capabilities flags */
 #define SMB2_GLOBAL_CAP_DFS            0x00000001
 #define SMB2_GLOBAL_CAP_LEASING                0x00000002 /* Resp only New to SMB2.1 */