Fix reconnect to not defer smb3 session reconnect long after socket reconnect

[ Upstream commit 4fcd1813e6404dd4420c7d12fb483f9320f0bf93 ]

Azure server blocks clients that open a socket and don't do anything on it.
In our reconnect scenarios, we can reconnect the tcp session and
detect the socket is available but we defer the negprot and SMB3 session
setup and tree connect reconnection until the next i/o is requested, but
this looks suspicous to some servers who expect SMB3 negprog and session
setup soon after a socket is created.

In the echo thread, reconnect SMB3 sessions and tree connections
that are disconnected.  A later patch will replay persistent (and
resilient) handle opens.

CC: Stable <stable@vger.kernel.org>
Signed-off-by: Steve French <steve.french@primarydata.com>
Acked-by: Pavel Shilovsky <pshilovsky@samba.org>
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>

diff --git a/fs/cifs/connect.c b/fs/cifs/connect.c
index 82ebe7dbd834d89ab015e62abfba839324c5a5de..db97215a23b29adb7863914225f12e6add58ef57 100644 (file)
--- a/fs/cifs/connect.c
+++ b/fs/cifs/connect.c
@@ -413,7 +413,9 @@ cifs_echo_request(struct work_struct *work)
         * server->ops->need_neg() == true. Also, no need to ping if
         * we got a response recently.
         */
-       if (!server->ops->need_neg || server->ops->need_neg(server) ||
+
+       if (server->tcpStatus == CifsNeedReconnect ||
+           server->tcpStatus == CifsExiting || server->tcpStatus == CifsNew ||
            (server->ops->can_echo && !server->ops->can_echo(server)) ||
            time_before(jiffies, server->lstrp + SMB_ECHO_INTERVAL - HZ))
                goto requeue_echo;

diff --git a/fs/cifs/smb2pdu.c b/fs/cifs/smb2pdu.c
index 33562819b5e71a3fc64e4f283452d051c250fe90..d759ecdfa9d6591a6777d63615f17b6834146e78 100644 (file)
--- a/fs/cifs/smb2pdu.c
+++ b/fs/cifs/smb2pdu.c
@@ -1623,6 +1623,33 @@ SMB2_echo(struct TCP_Server_Info *server)
 
        cifs_dbg(FYI, "In echo request\n");
 
+       if (server->tcpStatus == CifsNeedNegotiate) {
+               struct list_head *tmp, *tmp2;
+               struct cifs_ses *ses;
+               struct cifs_tcon *tcon;
+
+               cifs_dbg(FYI, "Need negotiate, reconnecting tcons\n");
+               spin_lock(&cifs_tcp_ses_lock);
+               list_for_each(tmp, &server->smb_ses_list) {
+                       ses = list_entry(tmp, struct cifs_ses, smb_ses_list);
+                       list_for_each(tmp2, &ses->tcon_list) {
+                               tcon = list_entry(tmp2, struct cifs_tcon,
+                                                 tcon_list);
+                               /* add check for persistent handle reconnect */
+                               if (tcon && tcon->need_reconnect) {
+                                       spin_unlock(&cifs_tcp_ses_lock);
+                                       rc = smb2_reconnect(SMB2_ECHO, tcon);
+                                       spin_lock(&cifs_tcp_ses_lock);
+                               }
+                       }
+               }
+               spin_unlock(&cifs_tcp_ses_lock);
+       }
+
+       /* if no session, renegotiate failed above */
+       if (server->tcpStatus == CifsNeedNegotiate)
+               return -EIO;
+
        rc = small_smb2_init(SMB2_ECHO, NULL, (void **)&req);
        if (rc)
                return rc;