Pull btrfs fix from David Sterba:
"A one-liner that prevents leaking an internal error value 1 out of the
ftruncate syscall.
This has been observed in practice. The steps to reproduce make a
common pattern (open/write/fync/ftruncate) but also need the
application to not check only for negative values and happens only for
compressed inlined files.
The conditions are narrow but as this could break userspace I think
it's better to merge it now and not wait for the merge window"
* tag 'for-4.17-rc6-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux:
Btrfs: fix error handling in btrfs_truncate()