From: Ronnie Sahlberg <lsahlber@xxxxxxxxxx> [ Upstream commit e6c47dd0da1e3a484e778046fc10da0b20606a86 ] 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@xxxxxxxxxx> Signed-off-by: Steve French <stfrench@xxxxxxxxxxxxx> Signed-off-by: Sasha Levin <alexander.levin@xxxxxxxxxxxxx> --- fs/cifs/smb2misc.c | 7 +++++++ 1 file changed, 7 insertions(+) diff --git a/fs/cifs/smb2misc.c b/fs/cifs/smb2misc.c index 967dfe656ced..e96a74da756f 100644 --- a/fs/cifs/smb2misc.c +++ b/fs/cifs/smb2misc.c @@ -208,6 +208,13 @@ smb2_check_message(char *buf, unsigned int length, struct TCP_Server_Info *srvr) if (clc_len == 4 + 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 -- 2.17.1
