I don't think syzkaller ones are more relevant to 5.1 then the rest of the patches applied to 4.19. If anything, its the other way around. According to syzbot dashboard, it is being run on LTS kernels, not on latest stable.
Please forgive me if my language caused confusion, when I said "please apply to 4.19" I meant 4.19+.
So is anything else needed to be done here, or are we all caught up and everything merged properly?
All the needed patches have been merged, but Upstream commit 146d62e5a5867fbf84490d82455718bfb10fe824 ("ovl: detect overlapping layers") did introduce a regression to docker and friends into stable kernels :-/
The fix commit is already tested and waiting in linux-next: 0be0bfd2de9d ("ovl: fix regression caused by overlapping layers detection") but did not hit upstream yet. When it does, will need to apply it to v4.19+
Thanks, Amir.