cifs: Only free DFS target list if we actually got one

Fix potential NULL ptr deref when DFS target list is empty.

Signed-off-by: Paulo Alcantara <palcantara@suse.de>
Reviewed-by: Aurelien Aptel <aaptel@suse.com>
Signed-off-by: Steve French <stfrench@microsoft.com>

diff --git a/fs/cifs/connect.c b/fs/cifs/connect.c
index ec2498f..80ef165 100644 (file)
--- a/fs/cifs/connect.c
+++ b/fs/cifs/connect.c
@@ -452,8 +452,8 @@ cifs_reconnect(struct TCP_Server_Info *server)
        struct mid_q_entry *mid_entry;
        struct list_head retry_list;
 #ifdef CONFIG_CIFS_DFS_UPCALL
-       struct cifs_sb_info *cifs_sb;
-       struct dfs_cache_tgt_list tgt_list;
+       struct cifs_sb_info *cifs_sb = NULL;
+       struct dfs_cache_tgt_list tgt_list = {0};
        struct dfs_cache_tgt_iterator *tgt_it = NULL;
 #endif
 
@@ -592,8 +592,8 @@ cifs_reconnect(struct TCP_Server_Info *server)
                        cifs_dbg(VFS, "%s: failed to update vol info in DFS cache: rc = %d\n",
                                 __func__, rc);
                }
+               dfs_cache_free_tgts(&tgt_list);
        }
-       dfs_cache_free_tgts(&tgt_list);
 #endif
        if (server->tcpStatus == CifsNeedNegotiate)
                mod_delayed_work(cifsiod_wq, &server->echo, 0);