Re: [PATCH v2] fs/{posix_acl,ext2,jfs,ceph}: apply umask if ACL support is disabled

From: Jan Kara
Date: Wed Oct 11 2023 - 09:59:31 EST


On Wed 11-10-23 14:27:49, Max Kellermann wrote:
> On Wed, Oct 11, 2023 at 2:18 PM Max Kellermann <max.kellermann@xxxxxxxxx> wrote:
> > But without the other filesystems. I'll resend it with just the
> > posix_acl.h hunk.
>
> Thinking again, I don't think this is the proper solution. This may
> server as a workaround so those broken filesystems don't suffer from
> this bug, but it's not proper.
>
> posix_acl_create() is only supposed to appy the umask if the inode
> supports ACLs; if not, the VFS is supposed to do it. But if the
> filesystem pretends to have ACL support but the kernel does not, it's
> really a filesystem bug. Hacking the umask code into
> posix_acl_create() for that inconsistent case doesn't sound right.
>
> A better workaround would be this patch:
> https://patchwork.kernel.org/project/linux-nfs/patch/151603744662.29035.4910161264124875658.stgit@xxxxxxxxxxxxxxxx-ag/
> I submitted it more than 5 years ago, it got one positive review, but
> was never merged.
>
> This patch enables the VFS's umask code even if the filesystem
> prerents to support ACLs. This still doesn't fix the filesystem bug,
> but makes VFS's behavior consistent.

OK, that solution works for me as well. I agree it seems a tad bit cleaner.
Christian, which one would you prefer?

Honza
--
Jan Kara <jack@xxxxxxxx>
SUSE Labs, CR