ext4: fix fencepost in s_first_meta_bg validation

commit 2ba3e6e8afc9b6188b471f27cf2b5e3cf34e7af2 upstream.

It is OK for s_first_meta_bg to be equal to the number of block group
descriptor blocks.  (It rarely happens, but it shouldn't cause any
problems.)

https://bugzilla.kernel.org/show_bug.cgi?id=194567

Fixes: 3a4b77cd47bb837b8557595ec7425f281f2ca1fe
Fixes: ext4: validate s_first_meta_bg at mount time
Change-Id: I401a32cc3fca59e08dd578b0e43c0429e17bd673
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
[bwh: Backported to 3.16: adjust context]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
CVE-2016-10208
Signed-off-by: Kevin F. Haggerty <haggertk@lineageos.org>
1 file changed