Merge tag '5.18-rc3-smb3-fixes' of git://git.samba.org/sfrench/cifs-2.6

Pull cifs fixes from Steve French:
 "Four fixes, two of them for stable:

   - fcollapse fix

   - reconnect lock fix

   - DFS oops fix

   - minor cleanup patch"

* tag '5.18-rc3-smb3-fixes' of git://git.samba.org/sfrench/cifs-2.6:
  cifs: destage any unwritten data to the server before calling copychunk_write
  cifs: use correct lock type in cifs_reconnect()
  cifs: fix NULL ptr dereference in refresh_mounts()
  cifs: Use kzalloc instead of kmalloc/memset

1 files changed, 10 insertions, 1 deletions

diff --git a/fs/cifs/connect.c b/fs/cifs/connect.c
index 902e8c6c0f9c..42e14f408856 100644
--- a/fs/cifs/connect.c
+++ b/fs/cifs/connect.c
@@ -534,12 +534,19 @@ int cifs_reconnect(struct TCP_Server_Info *server, bool mark_smb_session)
 {
 	/* 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
@@ -3675,9 +3682,11 @@ static void setup_server_referral_paths(struct mount_ctx *mnt_ctx)
 {
 	struct TCP_Server_Info *server = mnt_ctx->server;
 
+	mutex_lock(&server->refpath_lock);
 	server->origin_fullpath = mnt_ctx->origin_fullpath;
 	server->leaf_fullpath = mnt_ctx->leaf_fullpath;
 	server->current_fullpath = mnt_ctx->leaf_fullpath;
+	mutex_unlock(&server->refpath_lock);
 	mnt_ctx->origin_fullpath = mnt_ctx->leaf_fullpath = NULL;
 }