Pull ext4 fixes from Ted Ts'o:
 "Fix bugs that could cause kernel deadlocks or file system corruption
  while moving xattrs to expand the extended inode.

  Also add some sanity checks to the block group descriptors to make
  sure we don't end up overwriting the superblock"

* tag 'ext4_for_linus_stable' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4:
  ext4: avoid deadlock when expanding inode size
  ext4: properly align shifted xattrs when expanding inodes
  ext4: fix xattr shifting when expanding inodes part 2
  ext4: fix xattr shifting when expanding inodes
  ext4: validate that metadata blocks do not overlap superblock
  ext4: reserve xattr index for the Hurd