xfs: clamp the pNFS layout range to the maximum file size

xfs_fs_map_blocks() lets two bad layout ranges through. An offset of
2^63 or more is negative and passes "offset > limit". A length above
the limit, such as NFS4_UINT64_MAX, wraps "offset > limit - length"
and stays unclamped. With NFS4_UINT64_MAX, a read layout is built from
an uninitialized mapping.

Reject a negative offset and one at the limit, and clamp the length.
This needs "xfs: cap the block count of xfs_iomap_write_direct() at one
extent".

Fixes: 527851124d10 ("xfs: implement pNFS export operations")
Cc: stable@vger.kernel.org
Signed-off-by: Daejun Park <daejun7.park@samsung.com>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Pankaj Raghav <p.raghav@samsung.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Carlos Maiolino <cem@kernel.org>

0 files changed, 0 insertions, 0 deletions