1 files changed, 11 insertions, 7 deletions

diff --git a/fs/cifs/smb2pdu.c b/fs/cifs/smb2pdu.c
index c0d102615d0a..f9b74daf962a 100644
--- a/fs/cifs/smb2pdu.c
+++ b/fs/cifs/smb2pdu.c
@@ -416,18 +416,22 @@ SMB2_negotiate(const unsigned int xid, struct cifs_ses *ses)
 
         security_blob = smb2_get_data_area_len(&blob_offset, &blob_length,
                                                &rsp->hdr);
-        if (blob_length == 0) {
-                cifs_dbg(VFS, "missing security blob on negprot\n");
-                rc = -EIO;
-                goto neg_exit;
-        }
+        /*
+         * See MS-SMB2 section 2.2.4: if no blob, client picks default which
+         * for us will be
+         *      ses->sectype = RawNTLMSSP;
+         * but for time being this is our only auth choice so doesn't matter.
+         * We just found a server which sets blob length to zero expecting raw.
+         */
+        if (blob_length == 0)
+                cifs_dbg(FYI, "missing security blob on negprot\n");
 
         rc = cifs_enable_signing(server, ses->sign);
 #ifdef CONFIG_SMB2_ASN1  /* BB REMOVEME when updated asn1.c ready */
         if (rc)
                 goto neg_exit;
-
-        rc = decode_neg_token_init(security_blob, blob_length,
+        if (blob_length)
+                rc = decode_neg_token_init(security_blob, blob_length,
                                    &server->sec_type);
         if (rc == 1)
                 rc = 0;