Assume a user wanted to enable metadata only copy-up and passes metacopy=on.
If this feature can't be enabled, we disable metacopy=off and just leave
a warning in logs. metacopy=on requires redirect_dir=on (for upper dir)
or redirect_dir=follow (for non-upper mount).
As user does not see mount failure, he/she assumes metadata only copy-up
has been enabled but that's not the case.
So instead of disabling metacopy, return an error to user and leave a
message in logs. That will allow user to fix mount options and retry.
Reported-by: Daniel Walsh <dwalsh@xxxxxxxxxx>
Signed-off-by: Vivek Goyal <vgoyal@xxxxxxxxxx>
---
fs/overlayfs/super.c | 8 ++++----
1 file changed, 4 insertions(+), 4 deletions(-)
Index: rhvgoyal-linux/fs/overlayfs/super.c
===================================================================
--- rhvgoyal-linux.orig/fs/overlayfs/super.c 2018-10-26 09:07:46.474353806 -0400
+++ rhvgoyal-linux/fs/overlayfs/super.c 2018-10-26 09:28:23.195422393 -0400
@@ -574,11 +574,11 @@ static int ovl_parse_opt(char *opt, stru
/* metacopy feature with upper requires redirect_dir=on */
if (config->upperdir && config->metacopy && !config->redirect_dir) {
- pr_warn("overlayfs: metadata only copy up requires \"redirect_dir=on\", falling back to metacopy=off.\n");
- config->metacopy = false;
+ pr_err("overlayfs: metadata only copy up requires \"redirect_dir=on\".\n");
+ return -EINVAL;
} else if (config->metacopy && !config->redirect_follow) {
- pr_warn("overlayfs: metadata only copy up requires \"redirect_dir=follow\" on non-upper mount, falling back to metacopy=off.\n");
- config->metacopy = false;
+ pr_err("overlayfs: metadata only copy up requires either \"redirect_dir=follow\" or \"redirect_dir=on\" on non-upper mount.\n");
+ return -EINVAL;
}
return 0;
