[PATCH 3.16 116/306] Set previous session id correctly on SMB3 reconnect

Ben Hutchings
2017-02-15T23:42:43Z

From: Steve French <smfrench@gmail.com>

commit c2afb8147e69819885493edf3a7c1ce03aaf2d4e upstream.

Signed-off-by: Steve French <steve.french@primarydata.com>
Reported-by: David Goebel <davidgoe@microsoft.com>
[bwh: Backported to 3.16: adjust context]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
---
fs/cifs/smb2pdu.c | 5 +++++
fs/cifs/smb2pdu.h | 2 +-
2 files changed, 6 insertions(+), 1 deletion(-)

--- a/fs/cifs/smb2pdu.c
+++ b/fs/cifs/smb2pdu.c
@@ -566,6 +566,7 @@ SMB2_sess_setup(const unsigned int xid,
char *security_blob;
unsigned char *ntlmssp_blob = NULL;
bool use_spnego = false; /* else use raw ntlmssp */
+ u64 previous_session = ses->Suid;

cifs_dbg(FYI, "Session Setup\n");

@@ -602,6 +603,10 @@ ssetup_ntlmssp_authenticate:
return rc;

req->hdr.SessionId = 0; /* First session, not a reauthenticate */
+
+ /* if reconnect, we need to send previous sess id, otherwise it is 0 */
+ req->PreviousSessionId = previous_session;
+
req->VcNumber = 0; /* MBZ */
/* to enable echos and oplocks */
req->hdr.CreditRequest = cpu_to_le16(3);
--- a/fs/cifs/smb2pdu.h
+++ b/fs/cifs/smb2pdu.h
@@ -245,7 +245,7 @@ struct smb2_sess_setup_req {
__le32 Channel;
__le16 SecurityBufferOffset;
__le16 SecurityBufferLength;
- __le64 PreviousSessionId;
+ __u64 PreviousSessionId;
__u8 Buffer[1]; /* variable length GSS security buffer */
} __packed;