cifs: add fallback in is_path_accessible for old servers

The is_path_accessible check uses a QPathInfo call, which isn't
supported by ancient win9x era servers. Fall back to an older
SMBQueryInfo call if it fails with the magic error codes.

Cc: stable@kernel.org
Reported-and-Tested-by: Sandro Bonazzola <sandro.bonazzola@gmail.com>
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>

fs/cifs/connect.c

@@ -2673,6 +2673,11 @@ is_path_accessible(int xid, struct cifsTconInfo *tcon,
 			      0 /* not legacy */, cifs_sb->local_nls,
 			      cifs_sb->mnt_cifs_flags &
 				CIFS_MOUNT_MAP_SPECIAL_CHR);
+
+	if (rc == -EOPNOTSUPP || rc == -EINVAL)
+		rc = SMBQueryInformation(xid, tcon, full_path, pfile_info,
+				cifs_sb->local_nls, cifs_sb->mnt_cifs_flags &
+				  CIFS_MOUNT_MAP_SPECIAL_CHR);
 	kfree(pfile_info);
 	return rc;
 }