tree 64855be616c52cd522f2b25f24032a0a82253d9d
parent 5326a9705e422fc88c4b0df7abe9ac7f226ec199
author Theodore Ts'o <tytso@mit.edu> 1532779924 -0400
committer Ankit Jain <jankit@codeaurora.org> 1534137878 +0530

ext4: fix check to prevent initializing reserved inodes

Commit 8844618d8aa7: "ext4: only look at the bg_flags field if it is
valid" will complain if block group zero does not have the
EXT4_BG_INODE_ZEROED flag set.  Unfortunately, this is not correct,
since a freshly created file system has this flag cleared.  It gets
almost immediately after the file system is mounted read-write --- but
the following somewhat unlikely sequence will end up triggering a
false positive report of a corrupted file system:

   mkfs.ext4 /dev/vdc
   mount -o ro /dev/vdc /vdc
   mount -o remount,rw /dev/vdc

Instead, when initializing the inode table for block group zero, test
to make sure that itable_unused count is not too large, since that is
the case that will result in some or all of the reserved inodes
getting cleared.

This fixes the failures reported by Eric Whiteney when running
generic/230 and generic/231 in the the nojournal test case.

Fixes: 8844618d8aa7 ("ext4: only look at the bg_flags field if it is valid")
Reported-by: Eric Whitney <enwlinux@gmail.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Git-Repo: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
Git-Commit: 5012284700775a4e6e3fbe7eac4c543c4874b559
Change-Id: I9ae663e67e6ee32ef0c0e98a9e0ae9193cf7c880
Signed-off-by: Ankit Jain <jankit@codeaurora.org>