Upstream commit 3fe6e52f0626 ("ovl: override creds with the ones from
the superblock mounter") is present in v4.4.156 as 121b09d30d48. But the
patch has a few follow up fixes in upstream that also have to be applied
to 4.4:
d0e13f5bbe4b ("ovl: fix uid/gid when creating over whiteout") in v4.7-rc4
8fc646b44385 ("ovl: fix random return value on mount") in v4.13-rc2
The first patch should fix v4.4.156 regression reported here:
https://bugzilla.kernel.org/show_bug.cgi?id=201633.
Rest of stable kernels (4.9+) already have these followup fixes.
