The patch below does not apply to the 4.9-stable tree.
If someone wants it applied there, or to any other stable or longterm
tree, then please email the backport, including the original git commit
id to <stable@xxxxxxxxxxxxxxx>.
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
>From 8fc646b44385ff0a9853f6590497e43049eeb311 Mon Sep 17 00:00:00 2001
From: Amir Goldstein <amir73il@xxxxxxxxx>
Date: Tue, 11 Jul 2017 15:58:35 +0300
Subject: [PATCH] ovl: fix random return value on mount
On failure to prepare_creds(), mount fails with a random
return value, as err was last set to an integer cast of
a valid lower mnt pointer or set to 0 if inodes index feature
is enabled.
Reported-by: Dan Carpenter <dan.carpenter@xxxxxxxxxx>
Fixes: 3fe6e52f0626 ("ovl: override creds with the ones from ...")
Cc: <stable@xxxxxxxxxxxxxxx> # v4.7
Signed-off-by: Amir Goldstein <amir73il@xxxxxxxxx>
Signed-off-by: Miklos Szeredi <mszeredi@xxxxxxxxxx>
diff --git a/fs/overlayfs/super.c b/fs/overlayfs/super.c
index 44dc2d6ffe0f..1cf5d3538309 100644
--- a/fs/overlayfs/super.c
+++ b/fs/overlayfs/super.c
@@ -1090,6 +1090,7 @@ static int ovl_fill_super(struct super_block *sb, void *data, int silent)
else
sb->s_d_op = &ovl_dentry_operations;
+ err = -ENOMEM;
ufs->creator_cred = cred = prepare_creds();
if (!cred)
goto out_put_indexdir;