ext4: validate that metadata blocks do not overlap superblock
authorTheodore Ts'o <tytso@mit.edu>
Mon, 1 Aug 2016 04:51:02 +0000 (00:51 -0400)
committerTheodore Ts'o <tytso@mit.edu>
Mon, 1 Aug 2016 04:51:02 +0000 (00:51 -0400)
commit829fa70dddadf9dd041d62b82cd7cea63943899d
treef926bc39c86de7c7bb21b05e8f47d0844a28325e
parent3980bd3b406addb327d858aebd19e229ea340b9a
ext4: validate that metadata blocks do not overlap superblock

A number of fuzzing failures seem to be caused by allocation bitmaps
or other metadata blocks being pointed at the superblock.

This can cause kernel BUG or WARNings once the superblock is
overwritten, so validate the group descriptor blocks to make sure this
doesn't happen.

Cc: stable@vger.kernel.org
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
fs/ext4/super.c