cifs: check if SMB2 PDU size has been padded and suppress the warning

Some SMB2/3 servers, Win2016 but possibly others too, adds padding
not only between PDUs in a compound but also to the final PDU.
This padding extends the PDU to a multiple of 8 bytes.

Check if the unexpected length looks like this might be the case
and avoid triggering the log messages for :

  "SMB2 server sent bad RFC1001 len %d not %d\n"

Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
This commit is contained in:
Ronnie Sahlberg 2018-08-22 12:19:24 +10:00 committed by Steve French
parent 4d8dfafc5c
commit e6c47dd0da
1 changed files with 7 additions and 0 deletions

View File

@ -237,6 +237,13 @@ smb2_check_message(char *buf, unsigned int len, struct TCP_Server_Info *srvr)
if (clc_len == len + 1)
return 0;
/*
* Some windows servers (win2016) will pad also the final
* PDU in a compound to 8 bytes.
*/
if (((clc_len + 7) & ~7) == len)
return 0;
/*
* MacOS server pads after SMB2.1 write response with 3 bytes
* of junk. Other servers match RFC1001 len to actual