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

…econnect 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 <[email protected]> Signed-off-by: Steve French <[email protected]> Acked-by: Pavel Shilovsky <[email protected]>
jimmycarry · Jun 24, 2016 · 4fcd181 · 4fcd181
1 parent a6b6bef
commit 4fcd181
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Showing 2 changed files with 30 additions and 1 deletion.
diff --git a/fs/cifs/connect.c b/fs/cifs/connect.c
@@ -428,7 +428,9 @@ 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 + echo_interval - HZ))
 		goto requeue_echo;

diff --git a/fs/cifs/smb2pdu.c b/fs/cifs/smb2pdu.c
@@ -1812,6 +1812,33 @@ 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;