On Thu, Apr 26, 2018 at 12:10 PM, Vivek Goyal <vgoyal@xxxxxxxxxx> wrote: > ovl_copy_up() by default will only do metadata only copy up (if enabled). > That means when ovl_real_ioctl() calls ovl_real_file(), it will still > get the lower file (as ovl_real_file() opens data file and not metacopy). > And that means "chattr +i" will end up modifying lower inode. > > There seem to be two ways to solve this. > A. Open metacopy file in ovl_real_ioctl() and do operations on that > B. Force full copy up when FS_IOC_SETFLAGS is called. > > I am resorting to option B for now as it feels little safer option. If > there are performance issues due to this, we can revisit it. I agree with your choice. This doesn't seem like a performance sensitive use case, so simplicity is better. > > Signed-off-by: Vivek Goyal <vgoyal@xxxxxxxxxx> Reviewed-by: Amir Goldstein <amir73il@xxxxxxxxx> + nit > --- > fs/overlayfs/file.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/fs/overlayfs/file.c b/fs/overlayfs/file.c > index d61c8355b892..9a9efaac71f4 100644 > --- a/fs/overlayfs/file.c > +++ b/fs/overlayfs/file.c > @@ -397,7 +397,7 @@ long ovl_ioctl(struct file *file, unsigned int cmd, unsigned long arg) > if (ret) > return ret; > > - ret = ovl_copy_up(file_dentry(file)); > + ret = ovl_copy_up_flags(file_dentry(file), O_WRONLY); 2 options: either add a comment or a wrapper with meaningful name like ovl_copy_up_with_data. Thanks, Amir. -- To unsubscribe from this list: send the line "unsubscribe linux-unionfs" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
