xfs: make sure the rt allocator doesn't run off the end

There's an overflow bug in the realtime allocator.  If the rt volume is
large enough to handle a single allocation request that is larger than
the maximum bmap extent length and the rt bitmap ends exactly on a
bitmap block boundary, it's possible that the near allocator will try to
check the freeness of a range that extends past the end of the bitmap.
This fails with a corruption error and shuts down the fs.

Therefore, constrain maxlen so that the range scan cannot run off the
end of the rt bitmap.

Signed-off-by: Darrick J. Wong <[email protected]>
Reviewed-by: Christoph Hellwig <[email protected]>

0 files changed, 0 insertions, 0 deletions