From mboxrd@z Thu Jan 1 00:00:00 1970 From: Andrew Martin Subject: Re: "CIFS VFS: SMB response too short (9 bytes)" when copying data from CIFS mount Date: Wed, 30 Sep 2015 17:03:31 -0500 (CDT) Message-ID: <944083651.87203.1443650611671.JavaMail.zimbra@xes-inc.com> References: <1936200018.81178.1443479619664.JavaMail.zimbra@xes-inc.com> <1731839987.81462.1443479968995.JavaMail.zimbra@xes-inc.com> <1744736878.52548.1443542655076.JavaMail.zimbra@xes-inc.com> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Cc: linux-cifs-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, samba-technical To: Steve French Return-path: In-Reply-To: Sender: linux-cifs-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org List-ID: ----- Original Message ----- > From: "Steve French" > To: "Andrew Martin" > Cc: linux-cifs-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, "samba-technical" > Sent: Tuesday, September 29, 2015 11:21:25 AM > Subject: Re: "CIFS VFS: SMB response too short (9 bytes)" when copying data from CIFS mount > > It sounds pretty straightforward if both wireshark and the Linux > kernel client agree and say that this old Samba server sent a > malformed response (presumably a CIFS ReadX response). Note that this > is an old version of Samba server - Samba 3.6 was released more than 4 > years ago. > > Try turning off unix extensions on the mount and/or setting rsize > smaller (which might change the behavior of the Samba server read > response). So try > 1) adding something like "rsize=60000" to the options you pass to the > mount command > 2) and as a different experiment try mounting with "nounix" to disable > CIFS unix extensions which would also have the affect of reducing the > maximum read size > 3) another option to try is to set max protocols in the server's > smb.conf to enable SMB2.0 support and try "vers=2.0" on mount > > My guess is that the bug is related to large CIFS read processing in > this old version of Samba. > > I also want to --- strongly --- encourage upgrade from Samba 3.6.3 to > at least Samba 4.1 (I use Samba 4.3). The additional security > features and capabilities which SMB2.1 and SMB3 bring (not just the > new protocol features and improved performance) are VERY helpful and > very important for security. > Steve, It looks like using either "nounix" or "rsize=60000" fixes the read error! I will also look into upgrading to Samba 4.1 ASAP - I would like to take advantage of the security and performance improvement of a more modern SMB protocol. Thanks again! Andrew