writing files larger than 2GB to overlayfs fails

[Cam Cope]

There's simply a missing flag, which was fixed here:
https://git.kernel.org/cgit/linux/kernel/git/stable/linux-stable.git/commit/?id=0480334

The patch claims it requires kernel 3.18+, but the overlayfs code in ubuntu's 3.16 kernel is already backported from later kernel revs.

break-fix: - 0480334fa60488d12ae101a02d7d9e1a3d03d7dd

[Luis Henriques (henrix)]

The lts-vivid kernel 3.19.0-40.45 (which should be in -proposed soon) already includes this fix as this commit was tagged for stable >= 3.18.

[Luis Henriques (henrix)]

This bug is awaiting verification that the kernel in -proposed solves the problem. Please test the kernel and update this bug with the results. If the problem is solved, change the tag 'verification-needed-utopic' to 'verification-done-utopic'.

If verification is not done by 5 working days from today, this fix will be dropped from the source code, and this bug will be closed.

See https://wiki.ubuntu.com/Testing/EnableProposed for documentation how to enable and use -proposed. Thank you!

[Cam Cope (ccope)]

Test procedure:

In 3.16.0-57-generic:
$ sudo dd if=/dev/zero of=/lower/f1 bs=4096 count=550000
550000+0 records in
550000+0 records out
2252800000 bytes (2.3 GB) copied, 4.00938 s, 562 MB/s
$ sudo mount -t overlayfs overlayfs -olowerdir=/lower,upperdir=/upper /mnt/overlayfs
$ sudo chmod 666 /mnt/overlayfs/f1
chmod: changing permissions of ‘f1’: Value too large for defined data type

Rebooted into 3.16.0-58-generic:
$ sudo mount -t overlayfs overlayfs -olowerdir=/lower,upperdir=/upper /mnt/overlayfs
$ sudo chmod 666 /mnt/overlayfs/f1
$ echo $?
0