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From:   Greg Kroah-Hartman <gregkh@linuxfoundation.org>
To:     linux-kernel@vger.kernel.org
Cc:     Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
        stable@vger.kernel.org, "Paulo Alcantara (SUSE)" <pc@cjr.nz>,
        Ronnie Sahlberg <lsahlber@redhat.com>,
        Steve French <stfrench@microsoft.com>
Subject: [PATCH 5.17 116/146] cifs: use correct lock type in cifs_reconnect()
Date:   Tue, 26 Apr 2022 10:21:51 +0200
Message-Id: <20220426081753.317688313@linuxfoundation.org>
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From: Paulo Alcantara <pc@cjr.nz>

commit cd70a3e8988a999c42d307d2616a5e7b6a33c7c8 upstream.

TCP_Server_Info::origin_fullpath and TCP_Server_Info::leaf_fullpath
are protected by refpath_lock mutex and not cifs_tcp_ses_lock
spinlock.

Signed-off-by: Paulo Alcantara (SUSE) <pc@cjr.nz>
Cc: stable@vger.kernel.org
Reviewed-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
 fs/cifs/connect.c |    9 ++++++++-
 1 file changed, 8 insertions(+), 1 deletion(-)

--- a/fs/cifs/connect.c
+++ b/fs/cifs/connect.c
@@ -534,12 +534,19 @@ int cifs_reconnect(struct TCP_Server_Inf
 {
 	/* If tcp session is not an dfs connection, then reconnect to last target server */
 	spin_lock(&cifs_tcp_ses_lock);
-	if (!server->is_dfs_conn || !server->origin_fullpath || !server->leaf_fullpath) {
+	if (!server->is_dfs_conn) {
 		spin_unlock(&cifs_tcp_ses_lock);
 		return __cifs_reconnect(server, mark_smb_session);
 	}
 	spin_unlock(&cifs_tcp_ses_lock);
 
+	mutex_lock(&server->refpath_lock);
+	if (!server->origin_fullpath || !server->leaf_fullpath) {
+		mutex_unlock(&server->refpath_lock);
+		return __cifs_reconnect(server, mark_smb_session);
+	}
+	mutex_unlock(&server->refpath_lock);
+
 	return reconnect_dfs_server(server);
 }
 #else