[PATCH] nvmet-file: clamp-down file namespace lba_shift

[kbusch@kernel.org (Keith Busch)]

On Wed, Mar 06, 2019@08:38:21PM +0000, Chaitanya Kulkarni wrote:
> On 3/6/19 12:19 PM, Sagi Grimberg wrote:
> > Quick look shows that this is coming from blk_queue_stack_limits for the
> > ns_head.
> > 
> > Looks like nvme_update_disk_info() is reading a bs=0:
> > --
> >           unsigned short bs = 1 << ns->lba_shift;
> > --
> > 
> > bs is 16 bits and lba_shift is 20
> > (coming directly from the tempfile file_inode(ns->file)->i_blkbits)
> > 
> > So this fixes that one as well. Regardless, I think bs should be
> > unsigned int?
> 
> Yes.

blk_queue_logical_block_size() takes an 'unsigned short', so be sure to
check 'bs' is less than USHRT_MAX.