Pull ext4 fixes from Ted Ts'o:
 "Fix some syzbot-detected bugs, as well as other bugs found by I/O
  injection testing.

  Change ext4's fallocate to consistently drop set[ug]id bits when an
  fallocate operation might possibly change the user-visible contents of
  a file.

  Also, improve handling of potentially invalid values in the the
  s_overhead_cluster superblock field to avoid ext4 returning a negative
  number of free blocks"

* tag 'ext4_for_linus_stable' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4:
  jbd2: fix a potential race while discarding reserved buffers after an abort
  ext4: update the cached overhead value in the superblock
  ext4: force overhead calculation if the s_overhead_cluster makes no sense
  ext4: fix overhead calculation to account for the reserved gdt blocks
  ext4, doc: fix incorrect h_reserved size
  ext4: limit length to bitmap_maxbytes - blocksize in punch_hole
  ext4: fix use-after-free in ext4_search_dir
  ext4: fix bug_on in start_this_handle during umount filesystem
  ext4: fix symlink file size not match to file content
  ext4: fix fallocate to use file_modified to update permissions consistently