smb: client: improve DFS mount check

Some servers may return error codes from REQ_GET_DFS_REFERRAL requests
that are unexpected by the client, so to make it easier, assume
non-DFS mounts when the client can't get the initial DFS referral of
@ctx->UNC in dfs_mount_share().

Signed-off-by: Paulo Alcantara (SUSE) <pc@manguebit.com>
Signed-off-by: Steve French <stfrench@microsoft.com>

diff --git a/fs/smb/client/dfs.c b/fs/smb/client/dfs.c
index dd06b8a0ff7a8f86fbc559b9299f61e408dd9a88..26d14dd0482efba9a8b43074deb837b503687005 100644 (file)
--- a/fs/smb/client/dfs.c
+++ b/fs/smb/client/dfs.c
@@ -264,8 +264,9 @@ int dfs_mount_share(struct cifs_mount_ctx *mnt_ctx, bool *isdfs)
        if (!nodfs) {
                rc = dfs_get_referral(mnt_ctx, ctx->UNC + 1, NULL, NULL);
                if (rc) {
-                       if (rc != -ENOENT && rc != -EOPNOTSUPP && rc != -EIO)
-                               return rc;
+                       cifs_dbg(FYI, "%s: no dfs referral for %s: %d\n",
+                                __func__, ctx->UNC + 1, rc);
+                       cifs_dbg(FYI, "%s: assuming non-dfs mount...\n", __func__);
                        nodfs = true;
                }
        }