I've backported fixes for several security issues involving filesystem
validation in btrfs.  All of these are already fixed in the later
stable branches.

I tested with the reproducers where available.  I also checked for
regressions with xfstests and didn't find any (but many tests fail with
or without these changes).

Ben.

-- 
Ben Hutchings, Software Developer                         Codethink Ltd
https://www.codethink.co.uk/                 Dale House, 35 Dale Street
                                     Manchester, M1 2HF, United Kingdom