Re: [PATCH] ovl: fix NULL pointer dereference

[Christoph Fritz <chf.fritz@googlemail.com>]

Hello Miklos

On Wed, 2022-01-12 at 19:33 +0100, Christoph Fritz wrote:
> This patch is fixing a NULL pointer dereference to get a recently
> introduced warning message working.

With that patch applied, a lot of these are popping up now:

[    7.132514] overlayfs: failed to retrieve upper fileattr (index/#26, err=-25)
[    7.141520] overlayfs: failed to retrieve upper fileattr (index/#27, err=-25)
[    8.699070] overlayfs: failed to retrieve upper fileattr (index/#7, err=-25)
[    8.715804] overlayfs: failed to retrieve upper fileattr (index/#8, err=-25)
[    8.723218] overlayfs: failed to retrieve upper fileattr (index/#9, err=-25)
[    8.829887] overlayfs: failed to retrieve upper fileattr (index/#43, err=-25)
[    9.387676] overlayfs: failed to retrieve upper fileattr (index/#a, err=-25)
[    9.667531] overlayfs: failed to retrieve upper fileattr (index/#b, err=-25)
[    9.874005] overlayfs: failed to retrieve upper fileattr (index/#c, err=-25)
[    9.934664] overlayfs: failed to retrieve upper fileattr (index/#58, err=-25)
[    9.942036] overlayfs: failed to retrieve upper fileattr (index/#59, err=-25)
[    9.949406] overlayfs: failed to retrieve upper fileattr (index/#60, err=-25)
[    9.956738] overlayfs: failed to retrieve upper fileattr (index/#61, err=-25)
[   10.311610] overlayfs: failed to retrieve upper fileattr (index/#d, err=-25)
[   10.712019] overlayfs: failed to retrieve upper fileattr (index/#e, err=-25)
[   31.901577] overlayfs: failed to retrieve upper fileattr (index/#64, err=-25)

These have been -ENOIOCTLCMD errors but got (falsely?) converted to
-ENOTTY by the recently introduced commit 5b0a414d06c3 ("ovl: fix filattr copy-up failure"):

+	if (err == -ENOIOCTLCMD)
+		err = -ENOTTY;

Any ideas?

Thanks
 -- Christoph