CIFSGetSrvInodeNumber() uses SMB_QUERY_FILE_INTERNAL_INFO (0x3ee) level which is SMB PASSTHROUGH level (>= 0x03e8). SMB PASSTHROUGH levels are supported only when server announce CAP_INFOLEVEL_PASSTHRU. So add guard in cifs_query_file_info() function which is the only user of CIFSGetSrvInodeNumber() function and returns -EOPNOTSUPP when server does not announce CAP_INFOLEVEL_PASSTHRU. Signed-off-by: Pali Rohár <pali@xxxxxxxxxx> --- fs/smb/client/smb1ops.c | 6 ++++++ 1 file changed, 6 insertions(+) diff --git a/fs/smb/client/smb1ops.c b/fs/smb/client/smb1ops.c index a0a15dda0949..d959097ec2d2 100644 --- a/fs/smb/client/smb1ops.c +++ b/fs/smb/client/smb1ops.c @@ -622,7 +622,13 @@ static int cifs_get_srv_inum(const unsigned int xid, struct cifs_tcon *tcon, * There may be higher info levels that work but are there Windows * server or network appliances for which IndexNumber field is not * guaranteed unique? + * + * CIFSGetSrvInodeNumber() uses SMB_QUERY_FILE_INTERNAL_INFO + * which is SMB PASSTHROUGH level therefore check for capability. + * Note that this function can be called with tcon == NULL. */ + if (tcon && !(tcon->ses->capabilities & CAP_INFOLEVEL_PASSTHRU)) + return -EOPNOTSUPP; return CIFSGetSrvInodeNumber(xid, tcon, full_path, uniqueid, cifs_sb->local_nls, cifs_remap(cifs_sb)); -- 2.20.1